JP4240941B2 - Semiconductor device manufacturing method and substrate processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate influence of contamination in reaction chambers and to secure a stable process in the respective reaction chambers when a substrate is continuously processed in the two reaction chambers. <P>SOLUTION: Gate valves 12 and 13 are opened and a wafer is transported to a reaction chamber PM1 from a cassette chamber CM1 through a transport chamber TM (T11). The valves 12 and 13 are closed and the wafer W is processed in PM1. The valve 13 is opened and the wafer is transported to TM from PM1. The valve 13 is closed, a valve 14 is opened and the wafer is transported to the reaction chamber PM2 from TM (T12). The valves 13 and 14 are closed and the wafer is processed in MP2. The valve 14 is opened and the wafer is transported to a preliminary chamber CS2 from PM2 through TM. The valve 14 is closed and the wafer is cooled in CS2. The wafer is cooled, the valve 12 is opened and it is transported to CM1 from CS2 through TM (T13). The valve 12 is closed and a continuous processing is terminated. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a method for manufacturing a semiconductor device in which different processes are successively performed on a substrate.
[0002]
[Prior art]
As DRAM is highly integrated, the area occupied by capacitor cells tends to decrease. However, as the integration becomes higher, the capacitance value of the capacitor is almost flat. As a method of ensuring the necessary and sufficient capacitor capacity value,
(A) Thinning the capacitive insulating film,
(B) Adoption of high dielectric constant insulating film,
(C) Expansion of electrode surface area
Is mentioned. However, in the method (a), Si used as a capacitive insulating film_ThreeN_FourThe film thinning has almost reached its limit. In the method (b), Ta having a high dielectric constant is used.₂O_FiveAlthough it is moving to the film, the dielectric constant is Si_ThreeN_FourIt is only about 2.5 times that of the film, and a large capacitor capacity value cannot be expected. Therefore, in reality, securing a large capacitor capacitance value must be dealt with by increasing the electrode surface area as in the method (c).
[0003]
The enlargement of the electrode surface area of (c) is greatly increased due to the three-dimensional structure. However, when the three-dimensional structure is deepened, a fine processing technique such as exposure depth of focus and dry etching becomes a problem. Therefore, a method different from the three-dimensional structure deepening is required. Among these different methods, a representative method is a method of forming HSG (Hemispherical Grained Silicon) (for example, Japanese Patent No. 2508948). This method is based on the premise that the surface of the amorphous silicon film is kept in a substantially clean state, and the thin film formation method is not particularly limited, whether it is a CVD method or an MBE method. A compound gas containing silicon is supplied to the surface of the film to form crystal nuclei on the surface of the amorphous silicon film. Thereafter, the supply of gas is stopped, crystal nuclei are grown, unevenness is generated on the silicon surface, and the electrode surface area is increased. For example, the surface area ratio of a polycrystalline silicon film formed at 600 ° C. is set to be twice or more.
[0004]
Regarding this HSG formation, it is necessary from the viewpoint of the yield of semiconductor devices that the HSG grain size and grain density are uniform. In the HSG formation technique, the surface state of the HSG is formed because the way the HSG is formed on the surface varies depending on the surface state of the wafer to be deposited, for example, the silicon wafer, and the uniformity of the HSG grain size and grain density changes. Control is very important.
[0005]
Further, it is necessary to dope phosphorus into the silicon film in order to suppress the depletion layer on the capacitor surface. Phosphorus doping is performed after HSG formation. Phosphorus (P) is previously implanted as a dopant into the silicon layer, which is the lower electrode forming the HSG, but the phosphorus on the surface of the silicon film becomes diluted during the HSG formation process. For this reason, phosphine (PH_ThreeHeat treatment in a phosphorus compound gas atmosphere such as_ThreeIn case of PH_ThreeAnnealing), the silicon film is doped with phosphorus. This PH_ThreePhosphorus doping technology by annealing has a different amount of doping in the silicon film depending on the surface state of the wafer to which phosphorus is diffused, and there is a problem in suppressing the depletion layer on the capacitor surface. Therefore, it is very important to control the surface state until phosphorus is diffused. .
[0006]
In general, HSG formation and PH_ThreeAnnealing is performed independently using a single process processing apparatus, and therefore each processing is performed discontinuously. Single HSG forming device and PH_ThreeHSG formation and PH using annealing equipment_ThreeWhen each annealing is performed, it is possible to stably exhibit the self-process performance in each apparatus. However, when a single process processing apparatus is used, a wafer on which HSG is formed from an HSG forming apparatus is changed to PH._ThreeWhen transported to the annealing apparatus, the wafer is exposed to the atmosphere. Once exposed, there is a problem that the surface state of the wafer deteriorates and the amount of phosphorus doping in the silicon film becomes unstable. Therefore PH_ThreeBefore transporting to the annealing device, it is necessary to perform pre-treatment such as surface cleaning and wet cleaning for cleaning, but this causes HSG shape deterioration, and surface state management until transport after pre-processing. Was necessary.
[0007]
Therefore, HSG generation and PH are also used for HSG formation._ThreeIt has been proposed to apply a continuous processing apparatus capable of continuously performing annealing. This includes a transfer chamber and a plurality of chambers communicating with the transfer chamber, and sequentially performs different processes on the wafer. By this application, the HSG capacitor electrode forming apparatus is combined with the HSG forming apparatus and the PH._ThreeIntegrating annealing equipment, HSG formation chamber and PH in one equipment_ThreeA continuous process processing apparatus provided with an annealing chamber. The plurality of chambers are a cassette chamber that accommodates a substrate, a first reaction chamber that forms an HSG, a PH_ThreeA second reaction chamber for annealing and a preliminary chamber for cooling the wafer are included. After HSG formation in the first reaction chamber, PH is continuously generated in the second reaction chamber._ThreeBy performing the annealing, the phosphorus doping amount in the silicon film is stabilized without exposing the wafer to the atmosphere.
[0008]
However, in the continuous process apparatus, it is inevitable that the first reaction chamber and the second reaction chamber communicate with each other through the transfer chamber during the transfer of the substrate. At that time, the atmosphere of the first reaction chamber is brought into the second reaction chamber from the first reaction chamber. In addition, the atmosphere of the second reaction chamber is brought from the second reaction chamber to the first reaction chamber. That is, cross contamination occurs between the first reaction chamber and the second reaction chamber. Cross contamination is undesirable because it degrades the process performance in both reaction chambers. Further, due to the mutual influence such as cross contamination, the surface state of the substrate is deteriorated, and the performance of the semiconductor device is lowered.
[0009]
Therefore, in the continuous process apparatus, generally, the pressure in the transfer chamber is set slightly higher than the pressure in the first reaction chamber and the second reaction chamber. This prevents each atmosphere from being brought into the transfer chamber from both the first reaction chamber and the second reaction chamber so that no cross-contamination occurs between the first reaction chamber and the second reaction chamber. Yes.
[0010]
In the pressure setting described above, after the formation of HSG in the first reaction chamber, PH in the second reaction chamber is reached._ThreeWhen the annealed wafer is transferred to the wafer cooling chamber via the transfer chamber, the pressure in the transfer chamber is higher than the pressure in the second reaction chamber, so that the atmosphere from the second reaction chamber is brought into the transfer chamber. Can be reduced. However, the PH adsorbed on the heated wafer transferred to the transfer chamber_ThreeDesorbs in the transfer chamber at about room temperature and contaminates the transfer chamber atmosphere with phosphorus. Therefore, when the wafer to be processed next is transferred from the cassette chamber to the first reaction chamber, since the pressure in the transfer chamber is higher than the pressure in the first reaction chamber, the contaminated transfer chamber atmosphere is transferred to the first reaction chamber. Inflow and phosphorus adheres to the wafer surface due to the atmosphere, which causes growth inhibition of HSG formation in the first reaction chamber.
[0011]
That is, in forming the HSG, it is not so important to bring the atmosphere from the first reaction chamber to the second reaction chamber, and it is important to bring the atmosphere from the second reaction chamber to the first reaction chamber. For this reason, even if the pressure in the transfer chamber is higher than that in each reaction chamber, it is possible to effectively prevent contamination by substances brought together with the wafer, even if atmospheric contamination that is brought in separately from the wafer can be prevented. I can't.
[0012]
[Problems to be solved by the invention]
By the way, in the manufacturing method of the semiconductor device which includes the transfer chamber and the first and second reaction chambers and sequentially performs different processes on the substrate in the first and second reaction chambers, the following three points are provided. is important.
[0013]
(1) Reduce the amount of contamination to the transfer chamber
(2) To reduce the amount of contamination in the reaction chamber
(3) To reduce the amount of contamination in the transfer chamber
That is, if the amount of contamination to the transfer chamber can be reduced, the amount of contamination to the reaction chamber due to transfer chamber contamination can be reduced. Further, if the amount of contamination in the reaction chamber can be reduced, the amount of contamination in the reaction chamber can be reduced even if there is contamination in the transfer chamber. Moreover, if the amount of contamination in the transfer chamber can be reduced, the amount of contamination from the transfer chamber to the reaction chamber can be reduced.
[0014]
However, in the prior art in which the pressure in the transfer chamber as described above is set higher than the pressure in the first and second reaction chambers, although (1) can be satisfied, the first and second reactions are carried out from the transfer chamber. Since the flow to the chamber is made, the condition (2) cannot be satisfied if the transfer chamber is contaminated. In addition, since the transfer chamber itself has no cleaning action, (3) cannot be satisfied once the transfer chamber is contaminated. Therefore, the processing performance in each reaction chamber deteriorates, and there is a problem that stable processing cannot be ensured.
[0015]
The problem of the present invention is to reduce the amount of contamination to the transfer chamber and to reduce the amount of contamination to the reaction chamber, thereby solving the above-mentioned problems of the prior art and without deteriorating the processing performance of the reaction chamber, An object of the present invention is to provide a method of manufacturing a semiconductor device capable of ensuring stable processing. In addition, the problem of the present invention is to solve the above-mentioned problems of the prior art by reducing the amount of contamination in the transfer chamber, and to ensure stable processing without deteriorating the processing performance of the reaction chamber. Another object of the present invention is to provide a method for manufacturing a semiconductor device.
[0016]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a step of transferring the substrate from the transfer chamber to the first reaction chamber by communicating the first reaction chamber with the transfer chamber, and disconnecting the communication between the first reaction chamber and the transfer chamber to the first reaction chamber. A step of subjecting the substrate to the first treatment, a step of communicating the first reaction chamber with the transfer chamber and transferring the substrate subjected to the first treatment to the transfer chamber, and a communication between the first reaction chamber and the transfer chamber. , A step of communicating the second reaction chamber with the transfer chamber and transferring the substrate transferred to the transfer chamber to the second reaction chamber, and a step of disconnecting the communication between the second reaction chamber and the transfer chamber. A step of applying a second treatment to the substrate in the chamber, and a step of transferring the substrate subjected to the second treatment from the second reaction chamber to the transfer chamber by communicating the second reaction chamber with the transfer chamber. The pressure in the first reaction chamber is larger than the pressure in the transfer chamber when at least each reaction chamber communicates with the transfer chamber, and the transfer chamber Characterized by greater than the pressure of the pressure in the second reaction chamber.
[0017]
Here, “the step of bringing the first reaction chamber into communication with the transfer chamber and transferring the substrate subjected to the first treatment to the transfer chamber, the step of disconnecting the communication between the first reaction chamber and the transfer chamber, the second reaction “The step of communicating the substrate transferred to the transfer chamber by communicating the chamber with the transfer chamber to the second reaction chamber” includes the following two methods. One is to connect the first reaction chamber to the transfer chamber to transfer the substrate from the first reaction chamber to the transfer chamber. After transfer, the first reaction chamber is disconnected from the transfer chamber. Thereafter, the second reaction chamber is communicated with the transfer chamber, and the substrate is transferred from the transfer chamber to the second reaction chamber. The first reaction chamber and the second reaction chamber are not simultaneously communicated with the transfer chamber. The other one is to connect the first reaction chamber and the second reaction chamber to the transfer chamber and transfer the substrate from the first reaction chamber to the second reaction chamber via the transfer chamber. And the second reaction chamber communicates with the transfer chamber at the same time.
[0018]
When communicating each reaction chamber and the transfer chamber, if the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber, the amount of atmosphere brought into the first reaction chamber from the transfer chamber is reduced ((2 )). Further, when the reaction chamber and the transfer chamber are communicated with each other, if the pressure in the transfer chamber is made larger than the pressure in the second reaction chamber, the amount of atmosphere brought into the transfer chamber from the second reaction chamber is reduced (see above). (1)). Accordingly, when communicating at least each reaction chamber and the transfer chamber, if the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber and the pressure in the transfer chamber is made larger than the pressure in the second reaction chamber, When the substrate is transferred through the chamber, the amount of contamination from the second reaction chamber and the transfer chamber to the first reaction chamber can be reduced. As a result, the substrate processing process in the first reaction chamber can be secured stably.
[0019]
According to a second aspect of the present invention, the step of communicating the first reaction chamber with the transfer chamber and transferring the substrate from the transfer chamber to the first reaction chamber, and the communication between the first reaction chamber and the transfer chamber are cut off to the first reaction chamber. A step of subjecting the substrate to the first treatment, a step of communicating the first reaction chamber with the transfer chamber and transferring the substrate subjected to the first treatment to the transfer chamber, and a communication between the first reaction chamber and the transfer chamber. A step of connecting the second reaction chamber to the transfer chamber, transferring the substrate transferred to the transfer chamber to the second reaction chamber, and disconnecting the second reaction chamber from the transfer chamber. A step of subjecting the substrate to the second treatment in the reaction chamber; a step of communicating the second treatment chamber to the transfer chamber by communicating the second reaction chamber with the transfer chamber; A step of disconnecting the communication between the reaction chamber and the transfer chamber and continuing the state, and transferring the substrate subjected to at least the second treatment from the second reaction chamber to the transfer chamber. In order to perform the transfer, the transfer chamber is cycle purged while the second reaction chamber and the transfer chamber are in communication with each other and / or after the communication between the second reaction chamber and the transfer chamber is cut off. .
[0020]
In order to transfer the substrate subjected to the second treatment from the second reaction chamber, when the transfer chamber is cycle purged while the second reaction chamber and the transfer chamber are in communication, the substrate is brought into the transfer chamber from the second reaction chamber. Atmosphere can be removed from the transfer chamber, and even after the communication between the second reaction chamber and the transfer chamber is cut off, the transfer chamber can be cleaned by cycle purging ((3) above). Therefore, in order to transfer at least the substrate subjected to the second treatment from the second reaction chamber, the second reaction chamber and the transfer chamber communicate with each other, and / or the second reaction chamber and the transfer chamber communicate with each other. If the transfer chamber is cycle purged after the refusal, the amount of contamination from the transfer chamber to the first reaction chamber can be reduced ((2) above). As a result, the substrate processing process in the first reaction chamber can be secured stably.
[0021]
In the case of continuously batch processing the substrates using the second invention, the next substrate is immediately transferred to the transfer chamber after the preceding substrate subjected to the first processing is transferred to the second reaction chamber via the transfer chamber. It is preferable that a standby time is provided without being transferred to the first reaction chamber via the first and the transfer chamber is cycle purged during this standby time. If a transfer chamber is cycle purged even during the standby time by providing a standby time, the transfer chamber is cleaned. Therefore, when the next substrate is transferred to the first reaction chamber via the transfer chamber, the substrate to be processed next is processed. Is not contaminated by the transfer chamber atmosphere.
[0022]
3rd invention WHEREIN: In 1st or 2nd invention, said 1st process is a process which forms HSG, and said 2nd process is a process which dopes phosphorus with respect to HSG. Features.
[0023]
When communicating at least each reaction chamber and the transfer chamber, if the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber and the pressure in the transfer chamber is made larger than the pressure in the second reaction chamber, the transfer chamber is When the substrate is transferred via the first reaction chamber, the amount of phosphorus brought into the first reaction chamber from the second reaction chamber can be reduced. As a result, growth inhibition of HSG formation due to phosphorus in the first reaction chamber can be prevented. Further, in order to transfer at least the substrate subjected to the second treatment from the second reaction chamber, the second reaction chamber and the transfer chamber communicate with each other and / or the second reaction chamber and the transfer chamber communicate with each other. If the transfer chamber is cycle purged after the refusal, the phosphorus is brought into the transfer chamber from the second reaction chamber, or even if the transfer chamber is contaminated with phosphorus, the phosphorus is not brought into the first reaction chamber. Since it is excluded from the transfer chamber, the amount of phosphorus brought into the first reaction chamber from the second reaction chamber can be reduced. As a result, growth inhibition of HSG formation due to phosphorus in the first reaction chamber can be prevented.
[0024]
In a fourth aspect based on the third aspect, the second process is different from the HSG in PH._ThreeIt is a process for performing annealing.
[0025]
PH in the second reaction chamber_ThreeThe annealed substrate is transferred to the transfer chamber, and is adsorbed on the substrate._ThreeEven if desorbed in the transfer chamber, the transfer chamber atmosphere is cleaned by cycle purge, so that the transfer chamber atmosphere is not contaminated with phosphorus. Therefore, when the substrate to be processed next is transferred to the first reaction chamber via the transfer chamber, phosphorus does not adhere to the surface of the substrate to be processed next, so that growth inhibition of HSG formation is caused by phosphorus. It will not provoke.
[0026]
According to a fifth invention, in the first invention, in order to transport the substrate subjected to at least the second treatment from the second reaction chamber, the second reaction chamber and the transfer chamber communicate with each other, and / or After the communication between the second reaction chamber and the transfer chamber is cut off, the transfer chamber is cycle purged.
[0027]
Further, if the transfer chamber is cycle purged, the transfer chamber is maintained in a clean atmosphere, so that the amount of atmosphere brought from the second reaction chamber to the first reaction chamber is reduced, and the first reaction chamber is changed from the first reaction chamber to the first reaction chamber. The amount of atmosphere brought into the reaction chamber 2 is also reduced. Therefore, since cross contamination can be reduced (the above (1) to (3)), a more stable process can be performed without deteriorating each process performance in the first reaction chamber and the second reaction chamber.
[0028]
The sixth invention includes a step of communicating the reaction chamber with the transfer chamber and transferring the substrate from the transfer chamber to the reaction chamber, and a step of blocking the communication between the reaction chamber and the transfer chamber and subjecting the substrate to the treatment in the reaction chamber. And a step of transferring the processed substrate from the reaction chamber to the transfer chamber by communicating the reaction chamber with the transfer chamber, and at least a reaction chamber for transferring the processed substrate from the reaction chamber to the transfer chamber; The transfer chamber is cycle purged while the transfer chamber is in communication or / and after the communication between the reaction chamber and the transfer chamber is cut off.
[0029]
Cycle purge the transfer chamber while the reaction chamber is in communication with the transfer chamber and / or after disconnecting the reaction chamber from the transfer chamber to transfer at least the processed substrate from the reaction chamber to the transfer chamber Then, even if the reaction chamber atmosphere flows into the transfer chamber from the reaction chamber or contamination occurs in the transfer chamber, the atmosphere and contamination flowing into the transfer chamber are excluded from the transfer chamber. Therefore, the transfer chamber can be cleaned, and the process performance of the reaction chamber can be ensured.
[0030]
According to a seventh aspect of the present invention, there is provided a first reaction chamber that performs a first process on a substrate, a second reaction chamber that performs a second process on a substrate, and each reaction chamber. A transfer chamber for transferring the substrate, a first gate valve for opening and closing between the transfer chamber and the first reaction chamber, a second gate valve for opening and closing between the transfer chamber and the second reaction chamber, When opening / closing at least the first gate valve and / or the second gate valve, the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber, and the pressure in the transfer chamber is set to the second reaction chamber. And a control device for controlling the pressure so as to be larger than the pressure.
[0031]
A substrate comprising a first reaction chamber, a second reaction chamber, and a transfer chamber that communicates with each reaction chamber via first and second gate valves and transfers the substrate to and from each reaction chamber. In the processing apparatus, when the control device is provided to open and close at least the first gate valve and / or the second gate valve, the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber and the transfer is performed. Since the pressure in the chamber is controlled to be larger than the pressure in the second reaction chamber, the amount of atmosphere brought into the first reaction chamber from the second reaction chamber can be reduced.
[0032]
According to an eighth aspect of the present invention, there is provided a first reaction chamber that performs a first process on a substrate, a second reaction chamber that performs a second process on a substrate, and each reaction chamber. A transfer chamber for transferring the substrate, a first gate valve for opening and closing between the transfer chamber and the first reaction chamber, a second gate valve for opening and closing between the transfer chamber and the second reaction chamber, And a control device that controls to cycle purge the inside of the transfer chamber after at least a period when the second gate valve is open and / or after the second gate valve is closed after the period.
[0033]
A substrate comprising a first reaction chamber, a second reaction chamber, and a transfer chamber that communicates with each reaction chamber via first and second gate valves and transfers the substrate to and from each reaction chamber. In the processing apparatus, since the control apparatus has a control device and controls to carry out a cycle purge of the transfer chamber after at least the second gate valve is open and / or after the second gate valve is closed after the period, The transfer chamber can be cleaned, and the amount of atmosphere brought from the transfer chamber to the first reaction chamber can be reduced.
[0034]
According to a ninth invention, in the seventh or eighth invention, the first process is a process for forming HSG, and the second process is a process for doping HSG with phosphorus. Features.
[0035]
When communicating at least each reaction chamber and the transfer chamber, if the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber and the pressure in the transfer chamber is made larger than the pressure in the second reaction chamber, the transfer chamber is When the substrate is transferred via the first reaction chamber, the amount of phosphorus brought into the first reaction chamber from the second reaction chamber can be reduced. As a result, growth inhibition of HSG formation due to phosphorus in the first reaction chamber can be prevented. Further, in order to transfer at least the substrate subjected to the second treatment from the second reaction chamber, the second reaction chamber and the transfer chamber communicate with each other and / or the second reaction chamber and the transfer chamber communicate with each other. If the transfer chamber is cycle purged after the refusal, the phosphorus is brought into the transfer chamber from the second reaction chamber, or even if the transfer chamber is contaminated with phosphorus, the phosphorus is not brought into the first reaction chamber. Since it is excluded from the transfer chamber, the amount of phosphorus brought into the first reaction chamber from the second reaction chamber can be reduced. As a result, growth inhibition of HSG formation due to phosphorus in the first reaction chamber can be prevented.
[0036]
In a tenth aspect based on the ninth aspect, the second process is different from the HSG in PH._ThreeIt is a process for performing annealing.
[0037]
PH in the second reaction chamber_ThreeThe annealed substrate is transferred to the transfer chamber, and is adsorbed on the substrate._ThreeEven if desorbed in the transfer chamber, the transfer chamber atmosphere is cleaned by cycle purge, so that the transfer chamber atmosphere is not contaminated with phosphorus. Therefore, when the substrate to be processed next is transferred to the first reaction chamber via the transfer chamber, phosphorus does not adhere to the surface of the substrate to be processed next, so that growth inhibition of HSG formation is caused by phosphorus. It will not provoke.
[0038]
According to an eleventh aspect of the present invention, in the seventh aspect of the present invention, the control device further includes at least a period during which the second gate valve is open and / or after the second gate valve is closed after the period, It is characterized in that it has a function of controlling to purge the cycle.
[0039]
When the transfer chamber is further subjected to a cycle purge at least for a period during which the second gate valve is open and / or for a while after the second gate valve is closed, the first reaction is performed from the second reaction chamber. The amount of atmosphere brought into the chamber is reduced, and the transfer chamber is maintained in a clean atmosphere, so that the amount of atmosphere brought from the first reaction chamber to the second reaction chamber is also reduced. Therefore, a more stable process can be performed without degrading each process performance in the first reaction chamber and the second reaction chamber.
[0040]
A twelfth invention includes a reaction chamber for processing a substrate, a transfer chamber communicating with the reaction chamber and transferring the substrate between the reaction chamber, a gate valve for opening and closing between the transfer chamber and the reaction chamber, And a control device that controls to purge the inside of the transfer chamber after the gate valve is open and / or after the gate valve is closed after the period.
[0041]
When the transfer chamber is cycle purged during a period when the gate valve is open and / or for a predetermined period after the gate valve is closed after that period, the atmosphere flowing into the transfer chamber even if the reaction chamber atmosphere flows into the transfer chamber from the reaction chamber Excluded from the transfer chamber. Therefore, the transfer chamber can be cleaned, and the process performance of the reaction chamber can be ensured.
[0042]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a semiconductor device manufacturing method according to the present invention will be described below. Here, HSG is formed on the amorphous silicon film on the wafer, and PH_ThreeA case where a capacitor electrode part is formed by annealing will be described.
[0043]
FIG. 5 shows a schematic plan view of a single wafer type film forming apparatus for carrying out a method for manufacturing a semiconductor device. A transfer chamber TM is arranged in the center, and a wafer transfer robot 10 for transferring the wafer W is provided in the transfer chamber TM. A plurality of chambers communicating with each other via the transfer chamber TM are disposed around the transfer chamber TM. The plurality of chambers includes two adjacent cassette chambers CM1 and CM2, two opposing preliminary chambers CS1 and CS2, and two adjacent reaction chambers PM1 and PM2.
[0044]
In the cassette chamber, a first cassette chamber CM1 and a second cassette for loading a cassette storing unprocessed wafers into the apparatus from outside the apparatus and carrying out a cassette storing processed wafers from inside the apparatus to the outside of the apparatus. It consists of a room CM2. The cassette chambers CM1 and CM2 may be substrate loading / unloading chambers for directly loading / unloading wafers, rather than cassette chambers for loading / unloading cassettes containing wafers. The spare chamber is composed of a first spare chamber CS1 and a second spare chamber CS2 for cooling the processed wafer. The reaction chamber has a first reaction chamber PM1 for forming HSG on the wafer and a PH for the wafer on which HSG is formed._ThreeIt is comprised from 2nd reaction chamber PM2 which performs annealing.
[0045]
Communication portions between the two cassette chambers CM1 and CM2 and the transfer chamber TM can be opened and closed by gate valves 12 and 11, respectively. In addition, the communication part between the two reaction chambers PM1, PM2 and the transfer chamber TM can be opened and closed by gate valves 13, 14. Note that the two spare chambers CS1 and CS2 are always in communication with the transfer chamber TM.
[0046]
Each of the cassette chambers CM1 and CM2 including the transfer chamber TM and the reaction chambers PM1 and PM2 (hereinafter simply referred to as modules) has a gas supply port for supplying a processing gas and a gas exhaust port for exhausting the atmosphere in each module. Prepare. Gas supply systems 21 to 25 are connected to the gas supply ports of the cassette chambers CM2 and CM1, reaction chambers PM1 and PM2, and the transfer chamber TM, and gas exhaust systems 31 to 35 are connected to the gas exhaust ports. The gas supply systems 21 to 25 are provided with flow control devices 26 to 30 such as mass flow controllers (MFC) for controlling the gas flow rate, and the gas exhaust systems 31 to 35 are exhaust control devices 36 to 40 for controlling the exhaust pipe conductance. Is provided. By controlling the amount of gas supplied from the gas supply port and the amount of gas exhausted from the gas exhaust port, the inside of each module can be controlled independently at a predetermined pressure. Further, by using a purge gas as the supply gas, the inside of each module can be purged independently. These pressure control and purge control are performed by the control means 50 that controls the control system including the gate valve.
[0047]
Next, referring to FIG. 5, (1) a pre-process, (2) an HSG formation process for forming HSG on the amorphous silicon film, and (3) PH_ThreeAn annealing process will be described.
(1) Pre-process
Before a silicon wafer having an amorphous silicon film formed on the surface is transferred from a clean room to a film forming apparatus, a natural oxide film or a chemical oxide film is cleaned and removed. Chemical oxide film is NH_FourOH + H₂O₂+ H₂It is formed on the amorphous silicon surface by a mixed liquid such as O. The cleaning is performed by, for example, cleaning with a 1% hydrofluoric acid aqueous solution for 1 minute. After removal, the substrate is dried using a spin dry dryer or the like.
[0048]
After performing the drying process, the wafer having the amorphous silicon film on the surface is transferred to the cassette chamber CM1 in the film forming apparatus while being quickly cleaned. In order to form a film in a clean state, it is necessary to prevent adhesion of contaminants in the clean room atmosphere onto the amorphous silicon surface and re-formation of a natural oxide film, and it is necessary to quickly transport the film to the cassette chamber CM1. If a large amount of contaminants or natural oxide film adheres to and forms on the amorphous silicon surface, for example, the silicon bond density differs in the state where the natural oxide film is formed on the surface, compared to the state on the clean amorphous silicon surface. For this reason, there is a problem that the HSG is not formed, the formation state of the HSG, that is, the particle size or density of the HSG is different, or the phosphorus doping amount cannot be secured, which causes a decrease in the yield of the semiconductor device.
[0049]
After the wafer is transferred to the cassette chamber CM1 as described above, the cassette chamber CM1 is purged with high purity nitrogen by exhausting from the gas exhaust system 32 while supplying the high purity nitrogen gas from the gas supply system 22. Reduce pressure. The reason for purging with high-purity nitrogen is to allow moisture to be sufficiently evaporated into the atmosphere by purging with dry nitrogen.
[0050]
The reason for reducing the pressure while purging is to prevent the moisture in the cassette chamber from becoming ice (solid). When the pressure is suddenly reduced, the water (liquid) adhering to the wafer surface and cassettes does not all become water vapor (gas), but when part of it becomes gas, the temperature is lowered by the heat taken away, and ice (solid) ). Since the ice melts by heat and becomes water after the wafer is transported into the reaction chamber, a part of the wafer surface is oxidized and hinders the formation of HSG. Second, an air flow is provided by purging, and the deposits on the wafer and cassette are discharged from the cassette chamber CM1. Thirdly, the residual material is replaced as much as possible by raising or lowering the pressure in the cassette chamber several times.
[0051]
The transfer chamber TM is always purged with nitrogen exhausted from the gas exhaust system 35 while being supplied from the gas supply system 25, and impurity substances present and generated in the transfer chamber TM are carried into the transfer chamber TM. It prevents it from adhering to the surface of the wafer.
[0052]
(2) HSG formation process
The HSG formation process is composed of (1) a process of forming crystal nuclei on the amorphous silicon film surface and (2) a process of growing the crystal nuclei to form undulating hemispherical crystal grains (HSG). .
(1) Step of forming crystal nuclei
After removing impurity substances such as oxygen and moisture in the atmosphere of the cassette chamber CM1, the gate valve 12 of the cassette chamber CM1 and the gate valve 13 of the first reaction chamber PM1 are opened, and the cassette chamber CM1 and the first reaction chamber PM1 Then, the wafer W is transferred from the cassette chamber CM1 to the reaction chamber PM1 via the transfer chamber TM by the wafer transfer robot 10 in the transfer chamber TM. After the transfer, the gate valves 12 and 13 are closed to cut off the communication between the cassette chamber CM1 and the first reaction chamber PM1 via the transfer chamber TM.
[0053]
The wafer W transferred to the reaction chamber PM1 is stabilized at a preset reaction chamber temperature of 600 to 630 ° C. Temperature stabilization is performed in a high vacuum, nitrogen, or non-reactive gas atmosphere. Here, the non-reactive gas means a gas that does not react with the amorphous silicon surface. The temperature stabilization time is preferably 5 minutes or less in consideration of both in-plane temperature stabilization of the wafer and suppression of crystallization of amorphous silicon (suppression of polycrystallization of the underlying amorphous silicon so as not to inhibit HSG formation). Thereafter, the stabilized reaction chamber temperature is maintained.
[0054]
In the case of a non-reactive gas atmosphere, after sufficiently removing them, monosilane (SiH as a process gas)_Four) At 20 to 200 sccm per minute for 2.0 to 2.5 minutes to form fine crystal nuclei on the amorphous silicon surface. The density of crystal nuclei tends to increase with increasing wafer temperature and nucleation time, and when the monosilane flow rate is reduced, it is necessary to increase the wafer temperature and nucleation time.
[0055]
(2) Process for growing HSGs by growing crystal nuclei
The supply of monosilane is stopped, and crystal nuclei formed on the amorphous silicon surface are grown by migration of silicon atoms to form crystal grains. The size of the crystal grains tends to increase with an increase in the grain growth time, and the surface area increase rate is almost maximized in 5 minutes, so that the time between 3 and 5 minutes is controlled. If the time is too long, the grains are combined to form large grains, and the target surface area increase rate in this step is reduced, so the time needs to be controlled.
[0056]
As described above, the cassette chamber CM1 is depressurized while being purged with high-purity nitrogen to maintain a clean amorphous silicon surface, and is directly transferred to the reaction chamber PM1 through the transfer chamber TM purged with nitrogen to form a stable HSG. Then, HSG with good uniformity in the wafer surface is formed.
[0057]
(3) PH _Three Annealing process
After forming the HSG in the reaction chamber PM1, the gate valve 13 of the reaction chamber PM1 is opened to connect the reaction chamber PM1 to the transfer chamber TM, and then the wafer on which the HSG is formed is removed from the reaction chamber PM1 by the wafer transfer robot 10. Transfer to transfer chamber TM. After the transfer, the gate valve 13 of the reaction chamber PM1 is closed to disconnect the reaction chamber PM1 from the transfer chamber TM. Thereafter, the gate valve 14 of the reaction chamber PM2 is opened to allow the reaction chamber PM2 to communicate with the transfer chamber TM, and then transferred from the transfer chamber TM to the reaction chamber PM2 by the wafer transfer robot 10. After the transfer, the gate valve 14 is closed to disconnect the reaction chamber PM2 from the transfer chamber TM.
[0058]
PH for wafer with HSG formed in reaction chamber PM2_ThreeAnnealing is performed. PH_ThreeThe annealing process is performed from the gas supply port via the gas supply system 24._ThreeA gas is supplied into the second reaction chamber PM2, and the HSG film formed on the wafer W is doped with P. Excess gas is exhausted through the gas exhaust system 34 from the exhaust port. Here, PH supplied to the wafer_ThreeThe gas is 100 to 5000 sccm. The temperature in the second reaction chamber is 600 to 750 ° C., and the pressure is 4,000 Pa (30 Torr) to 40,000 Pa (300 Torr).
[0059]
PH in reaction chamber PM2_ThreeAfter the annealing treatment, the gate valve 14 is opened to allow the reaction chamber PM2 and the transfer chamber TM to communicate with each other, and then the wafer transfer robot 10 transfers the PH from the reaction chamber PM2 to the spare chamber CS2 via the transfer chamber TM._ThreeThe annealed wafer is transferred. Thereafter, the gate valve 14 is closed, and the communication between the reaction chamber PM2 and the transfer chamber TM is cut off. After the wafer is sufficiently cooled in the spare chamber CS2, the gate valve 12 is opened, and the transfer chamber TM and the cassette chamber CM1 are communicated with each other, and then the cassette chamber is transferred from the spare chamber CS2 via the transfer chamber TM by the wafer transfer robot 10. The cooled wafer is transferred to CM1. In addition, you may convey to cassette chamber CM2. Hereinafter, the conveyance return chamber will be described as a cassette CM1. Thereafter, the gate valve 12 is closed, the communication between the cassette chamber CM1 and the transfer chamber TM is cut off, and the processing is completed.
[0060]
Capacitance electrode portions are formed on a large number of wafers by repeating the batch of the above-described series of steps as a batch. In this embodiment, one or two wafers are processed per batch. At this time, in order to improve the throughput by improving the number of treatments in both reaction chambers PM1, PM2, wafers to be processed in the preceding batch are transferred from the reaction chamber PM1 to the reaction chamber PM2, and then processed in the reaction chamber PM2. Wafers to be processed in the next batch are transferred from the cassette chamber CM1 to the reaction chamber PM1, and processed in the reaction chamber PM1.
[0061]
In such an apparatus involving wafer transfer, the gate valves 13 and 14 that isolate the atmosphere between the reaction chamber PM1 and the reaction chamber PM2 via the transfer chamber TM are repeatedly opened and closed each time the wafer is transferred. In the embodiment, since the gate valve 13 and the gate valve 14 are not opened at the same time, the reaction chamber PM1 and the reaction chamber PM2 do not directly communicate with each other through the transfer chamber TM. However, when the reaction chamber PM1 is communicated with the transfer chamber TM and then the reaction chamber PM2 is communicated with the transfer chamber TM, the reaction chamber PM1 and the reaction chamber PM2 are indirectly communicated with each other via the transfer chamber TM. . For this reason, unless any measure is taken, the reaction chambers PM1 and PM2 will be affected by contamination. In particular, the reaction chamber PM1 for HSG formation and PH_ThreeAlthough both processes performed in the reaction chamber PM2 for annealing are both greatly affected by the wafer surface state, the impurity that can be contaminated by the process gas used in both processes is phosphorus, and HSG The influence of phosphorus on formation can lead to HSG growth inhibition. When the gate valve is opened, phosphorus in the reaction chamber PM2 flows into the transfer chamber TM, phosphorus in the transfer chamber TM flows into the reaction chamber PM1, and phosphorus in the reaction chamber PM2 flows into the reaction chamber PM1 through the transfer chamber TM. In order to reduce the effect of phosphorus, in this embodiment, as described below, A. B. pressure balance control between chambers; Perform a cycle purge of the transfer chamber.
[0062]
A. Pressure control between chambers
The pressure between the modules in the transfer chamber TM and the reaction chambers PM1 and PM2 is controlled so as to achieve a pressure balance described later. This pressure control is performed by, for example, nitrogen purge. That is, the control means 50 controls the flow rate control devices 28, 29, and 30 to adjust the flow rate of nitrogen gas supplied from the gas supply port, and controls the exhaust control devices 38, 39, and 40, respectively. This is done by controlling the amount of exhaust exhausted from the mouth.
[0063]
The wafer is transferred to the reaction chamber PM1 via the transfer chamber TM. Further, the reaction chamber PM1 is transferred to the reaction chamber PM2 via the transfer chamber TM, and further transferred from the reaction chamber PM2 to the transfer chamber TM. In this embodiment, the flow direction of the gas when the gate valves 13 and 14 between the modules are opened is controlled in the conveyance. In this control, the respective module pressure balances are set as follows in order to reduce the amount of contamination brought into the reaction chamber PM1, which is affected by the removal of contamination from the reaction chamber PM2.
“Reaction chamber PM1> Transport chamber TM> Reaction chamber PM2”
[0064]
By setting the transfer chamber TM> the reaction chamber PM2, it is possible to reduce the amount of atmospheric contamination brought into the transfer chamber TM from the reaction chamber PM2 separately from the wafer. Further, by setting the reaction chamber PM1> the transfer chamber TM, the PH brought into the transfer chamber TM from the reaction chamber PM2 together with the wafer._ThreeEven if the carrier chamber TM is contaminated with phosphorus, the contaminated carrier chamber atmosphere can be prevented from flowing into the first reaction chamber PM1. Thereby, the inhibition of HSG growth due to phosphorus contamination can be improved.
[0065]
FIG. 3 shows a comparison of HSG growth performance in the conventional single process (Comparative Example 1), the conventional continuous process (Comparative Example 2), and the continuous process of the embodiment (Examples 1 and 2). The pressure balance of each module including the cassette chamber which is each process condition of Comparative Examples 1 and 2 and Examples 1 and 2 is as follows.
Single process conditions of Comparative Example 1
“Cassette chamber CM1 = reaction chamber PM1 <transfer chamber TM” (1)
Here, the reaction chamber PM2 does not exist because in the single process, HSG formation and PH are performed using two devices._ThreeAnnealing treatment is performed for each of the two because the pressure balance in the reaction chamber is the same.
Continuous treatment process conditions of Comparative Example 2
“Cassette chamber CM1 = reaction chamber PM1 <transfer chamber TM> reaction chamber PM2” (2)
Continuous treatment process conditions of Examples 1 and 2
“Cassette chamber CM1 <reaction chamber PM1> transfer chamber TM> reaction chamber PM2” (3)
The index of the HSG growth state is the wafer surface reflectance measurement result (average reflectance and variation). The larger the average reflectance, the better the occurrence of irregularities, and the smaller the variation, the better the formation of HSG. Therefore, in the case of continuous processing, the module pressure balance should be adjusted as in Examples 1 and 2.
“Reaction chamber PM1> Transport chamber TM> Reaction chamber PM2” (4)
It is good to set like this. Thereby, the remarkable formation deterioration as in Comparative Example 2 is eliminated, and the performance of the single process of Comparative Example 1 is brought close to that.
[0066]
The difference between Example 1 and Example 2 is the pressure. In Example 2, the nitrogen purge flow rate is increased more than in Example 1, and the overall pressure is set in the vicinity of 300 Pa. Under this condition, the average reflectance is substantially the same as the result of the condition set in the vicinity of 100 Pa in Example 1. However, the variation in the wafer surface is large. This is because the decrease in reflectance at the wafer position on the gate valve 13 side could not be sufficiently improved, and it is presumed to be the influence of phosphorus contamination brought in a very small amount into the first reaction chamber PM1.
[0067]
B. Add cycle purge
Therefore, in the present embodiment, “cycle purge in the transfer chamber TM” is further added to the pressure balance control described above.
[0068]
FIG. 4 shows a comparison table in which a cycle purge is further added to the above-described Examples 1 and 2. As shown in the figure, the number of cycle purges in the transfer chamber TM is compared between one and three times, and in order to improve the purge effect, as in the first and second embodiments, the result is set at around 100 Pa. A comparison is made with the result of increasing the nitrogen purge flow rate and setting the overall pressure to around 300 Pa.
[0069]
As shown in FIG. 4, it can be seen that the effect of improving the atmosphere is greater when the number of cycle purges is increased from 3 to 1, and the effect of improving the atmosphere is greater when the conveyance pressure is higher. As a result, in the nitrogen purge atmosphere at around 300 Pa, the cycle purge for improving the transfer chamber atmosphere is performed three times, thereby forming the HSG and PH._ThreeThe HSG growth in the continuous annealing process can be improved to the same growth as the HSG growth in the single process apparatus. This is because even if it is a trace amount, phosphorus contamination is not brought into the first reaction chamber PM1, and the decrease in reflectance at the wafer position on the gate valve 13 side can be sufficiently improved. It should be noted that the number of cycle purges is not limited to three as long as the throughput of the apparatus allows, but may be four or more.
[0070]
As described above, in addition to the pressure balance control between modules in addition to the inter-module pressure balance control, the atmosphere in the transfer chamber TM is improved and the influence of bringing out contamination from the reaction chamber PM2 is affected. Further contamination of the reaction chamber PM1 can be reduced. In particular, by carrying out the cycle purge at a high pressure a plurality of times, it can be improved to be equal to or higher than the single process of Comparative Example 1.
[0071]
Next, the timing of the substrate processing step when the inter-module pressure balance control and the transfer chamber cycle purge control are performed in forming the HSG film will be described with reference to FIG.
[0072]
As indicated by the arrows in the schematic apparatus diagram shown above the timing chart in FIG. 1, the wafer transfer path includes the first reaction chamber PM1 and the first reaction that perform HSG formation from the cassette chamber CM1 via the transfer chamber TM. PH from room PM1 via transfer room TM_ThreeThe second reaction chamber PM2 for annealing, the second preliminary chamber CS2 for cooling from the second reaction chamber PM2 via the transfer chamber TM, and the second preliminary chamber CS2 for returning to the cassette chamber CM1 via the transfer chamber TM. . One batch is completed when the wafer is transferred along this transfer path. By repeating this batch many times with a time difference, capacitive electrodes made of HSG films are formed on a large number of wafers. In FIG. 1, it is shown up to the middle of the third batch.
[0073]
(1) The first batch starts from the first conveyance T11 from CM1 to PM1, forms HSG in PM1, second conveyance T12 from PM1 to PM2, and PH in PM2._ThreeThe process is terminated by annealing, third transfer T13 from PM2 to CS2, cooling of the wafer at CS2, and fourth transfer T14 from CS2 to CM1.
[0074]
Here, the open / close state of the gate valves 13 and 14 separating the reaction chambers PM1 and 2 from the transfer chamber is as follows. In the first transfer T11, the gate valve 13 is open and the gate valve 14 is closed. When the HSG is formed, both the gate valves 13 and 14 are closed. In the second transfer T12, the gate valves 13 and 14 are not opened at the same time, and are opened and closed in the transfer process, such as opening / closing → close / close → close / open. PH_ThreeIn the annealing, both the gate valves 13 and 14 are closed. In the third transfer T13, the gate valve 13 is closed and the gate valve 14 is opened. During cooling, both the gate valves 13 and 14 are closed.
[0075]
In the first batch that involves opening and closing of the gate valve, the inter-module pressure balance control based on the equation (4) is performed during the first transport T11, the second transport T12, and the third transport T13. Thereby, the contamination by the airflow between modules is suppressed.
[0076]
In the first batch, the cycle purge of the transfer chamber TM is performed twice. In the first cycle purge C11, after the second transfer step T12 in which the wafer is taken out from the reaction chamber PM1 and transferred to PM2 through the transfer chamber TM, a standby time is provided, and the standby time is set to PH._ThreePerformed in parallel with the annealing step. Although the second batch can be started continuously after the end of the second transfer step T12, a standby time is provided for ensuring the cycle purge without starting the second batch. In this case, in consideration of the throughput of the apparatus, the waiting time for ensuring the cycle purge until the next wafer is brought into the reaction chamber PM1 after the wafer is taken out from the reaction chamber PM2 is within 1 to 3 minutes. It is preferable to do.
[0077]
This transfer chamber cycle purge C11 reduces the amount of contamination in the transfer chamber TM. Therefore, when the wafer to be processed next is transferred from the cassette chamber CM to the reaction chamber PM1 via the transfer chamber TM in the second batch, the transfer chamber TM is temporarily contaminated with phosphorus released from the first batch of wafers. Even if the transfer chamber TM is cycle purged before the second batch, phosphorus is exhausted from the transfer chamber TM before being brought into the reaction chamber PM1. As a result, phosphorus can be significantly reduced from being brought into the reaction chamber PM1.
[0078]
The second cycle purge C12 is performed across the transfer process from the reaction chamber PM2 to the cooling chamber CS2 and the cooling process in CS2 performed after the transfer process. When the wafer is transferred from the reaction chamber PM2 to the cooling chamber CS2, PH is transferred from the reaction chamber PM2 to the transfer chamber TM regardless of the differential pressure of TM> PM2._ThreeEven if leaks or PH_ThreeEven if phosphorus is desorbed from the adsorbed wafer, the PH leaked out by cycle purging the transfer chamber TM_ThreeAnd phosphorus are effectively exhausted from the transfer chamber TM. Therefore, phosphorus is not brought into the reaction chamber PM1. The time of the second cycle purge C12 is not limited as in the first cycle purge C11, but the PH brought into the transfer chamber TM from the reaction chamber PM2 together with the wafer is integrated._ThreeIs preferably equal to or longer than the time of the cycle purge C11.
[0079]
Here, the first transfer chamber cycle purge C11 is performed after the wafer transfer T12, whereas the second transfer chamber cycle purge C12 is also performed during the wafer transfer T13 for the following reason. In the first transfer chamber cycle purge C11, PH_ThreeSince the relationship with the reaction chamber PM2 can be cut off when the gate valve 14 before the annealing treatment is closed rather than when the gate valve 14 is open, the effect of reducing the amount of contamination in the transfer chamber TM is greater. is there. In the second transfer chamber cycle purge C12, PH_ThreeSince phosphorus is desorbed from the annealed wafer and contamination of the transfer chamber atmosphere starts, it is more effective to reduce the amount of contamination when the wafer is transferred from the reaction chamber PM2 to the cooling chamber CS2 after the gate valve 14 is closed. This is because it is large, and may be performed after the transfer process to the cooling chamber CS2.
[0080]
(2) The second batch is the PH of the first batch_ThreeIt starts during the annealing, after the cycle purge C11 is completed and the transfer chamber TM is cleaned. The batch contents are the same as the first time. The time required from the start of the first batch to the start of the second batch is the takt time Ta.
[0081]
(3) The third batch is PH of the second batch_ThreeIt starts during annealing and after the cycle purge C21 is completed.
[0082]
In this way, by repeating the batch many times, HSG is formed on a large number of wafers, and P is doped to form capacitive electrodes.
[0083]
By the way, the contents of the transfer chamber cycle purge described above are as shown in FIG. In the cycle purge, the transfer chamber TM is evacuated, and when the pressure becomes saturated (stops lowering) or reaches a predetermined pressure, nitrogen N is introduced into the transfer chamber TM.₂This is a purging method in which a cycle in which the pressure is once increased by supplying an inert gas or the like to purge the inside of the transfer chamber TM is repeated within a range that the waiting time permits. (For example, 300 Pa). This makes PH_ThreeSuch contaminants can be efficiently removed from the transfer chamber TM, and the amount of phosphorus contamination into the reaction chamber PM1 can be reduced.
[0084]
In the above-described embodiment, two examples of the case where the pressure balance between the modules is controlled and the case where the transfer chamber cycle purge is further added to the above are described. It has been described that the characteristics are particularly good when performing pressure balance control and transfer chamber cycle purge. However, the present invention is not limited to this. For example, it is possible to obtain an effect that contaminants can be efficiently removed only by carrying out the transfer chamber cycle purge alone. The pressure setting of each module, which is a process processing condition when performing cycle purge alone, is arbitrary, and may be the same as that in Comparative Example 2 in which the pressure in the transfer chamber TM is made higher than that in other chambers, for example. Also by this, compared with the comparative example 2, a favorable average reflectance and variation can be obtained.
[0085]
The pressure balance is set at least when the gate valve is opened / closed, but may be always set during the wafer transfer process or during the wafer processing. Similarly, the cycle purge is performed before the next wafer is transferred and when the processed wafer is transferred after the processed wafer is transferred, but may be always performed during the wafer processing.
[0086]
In the embodiment, since it is assumed that both of the preliminary chambers are cooling chambers, the case where the preliminary chamber is directly transferred from the cassette to the reaction chamber PM1 at the start of the processing has been described. However, one of the preliminary chambers is a heating chamber. In some cases, the present invention can be applied even when the cassette is once transported from the cassette to the preliminary chamber and then transported from the preliminary chamber to the reaction chamber via the transport chamber. On the contrary, it is also applicable to the case where the reaction chamber is directly transferred to the cassette chamber without going through the preliminary chamber.
[0087]
In addition, the treatment in the first reaction chamber is HSG formation treatment, and the treatment in the second reaction chamber is PH._ThreeAlthough annealing treatment is used, the present invention is not limited to these treatments, and can be applied to almost all treatments that require reduction of cross-contamination between the first reaction chamber and the second reaction chamber. It is.
[0088]
In the above-described embodiment, when there are two reaction chambers, the pressure balance between the modules is controlled and the transfer chamber is cycle purged. However, when there is one reaction chamber, at least In order to transfer the processed substrate from the reaction chamber to the transfer chamber, the reaction chamber and the transfer chamber are in communication with each other, and / or for a while after the communication is cut off, the transfer chamber is simply cycle purged. Good. Thereby, since the transfer chamber can be cleaned, the wafer is not contaminated in the transfer chamber when the next wafer is transferred to the reaction chamber via the transfer chamber.
[0089]
In the above-described embodiment, the gate valve is controlled so that the reaction chamber PM1, the transfer chamber TM, and the reaction chamber PM2 do not communicate with each other in the wafer transfer process (second transfer T12) from PM1 to PM2. However, the gate valve may be controlled so that the three chambers communicate with each other simultaneously. Specifically, after forming the HSG in the reaction chamber PM1, the gate valves 13 and 14 of the reaction chamber PM1 and the reaction chamber PM2 are opened, and the reaction chamber PM1 and the reaction chamber PM2 are communicated with each other via the transfer chamber TM. Thereafter, the wafer transfer robot 10 transfers the wafer from the reaction chamber PM1 to the reaction chamber PM2 via the transfer chamber TM. After the transfer, the gate valves 13 and 14 may be closed to cut off the communication between the reaction chamber PM1 and the reaction chamber PM2 via the transfer chamber TM.
[0090]
【The invention's effect】
According to the present invention, since the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber, the amount of contamination from the transfer chamber to the first reaction chamber can be reduced even if contamination occurs in the transfer chamber. Further, since the pressure in the transfer chamber is made larger than the pressure in the second reaction chamber, the amount of contamination from the second reaction chamber to the transfer chamber can be reduced. Therefore, stable processing can be performed without deteriorating the process performance of the reaction chamber.
[0091]
Further, according to the present invention, since the transfer chamber is cycle purged, the amount of contamination in the transfer chamber can be reduced even if the transfer chamber is contaminated. Further, even if the transfer chamber is contaminated, the transfer chamber can be cleaned, so that the amount of contamination from the transfer chamber to the reaction chamber can be reduced. Therefore, stable processing can be performed without deteriorating the process performance of the reaction chamber.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a batch process of a continuous process process according to an embodiment.
FIG. 2 is an explanatory diagram of a cycle purge content of a transfer chamber according to the embodiment.
FIG. 3 is a comparative diagram between a comparative example and an example showing a measurement result of wafer surface reflectivity due to a difference in pressure between modules.
FIG. 4 is a diagram of an example showing a wafer surface reflectance measurement result according to the number of cycle purges performed in addition to a difference in pressure between modules.
FIG. 5 is a schematic plan view of a continuous processing apparatus for carrying out the method for manufacturing a semiconductor device according to the present invention.
[Explanation of symbols]
CM1, CM2 First and second cassette chambers
TM transfer room
PM1 first reaction chamber (HSG formation chamber)
PM2 Second reaction chamber (PH_ThreeAnnealing room)
11-14 Gate valve
CS1, CS2 First and second spare chambers (wafer cooling chamber)

Claims (5)

Communicating the first reaction chamber with the transfer chamber and transferring the substrate from the transfer chamber to the first reaction chamber;
Cutting the communication between the first reaction chamber and the transfer chamber and applying the first treatment to the substrate in the first reaction chamber;
A step of communicating the substrate subjected to the first treatment by communicating the first reaction chamber with the transfer chamber to the transfer chamber;
Disconnecting the communication between the first reaction chamber and the transfer chamber;
A step of communicating a substrate transferred to the transfer chamber by communicating the second reaction chamber with the transfer chamber to the second reaction chamber;
Cutting the communication between the second reaction chamber and the transfer chamber and applying the second treatment to the substrate in the second reaction chamber;
Having the second reaction chamber communicate with the transfer chamber and transferring the substrate subjected to the second treatment from the second reaction chamber to the transfer chamber,
When communicating at least each reaction chamber and the transfer chamber, the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber, and the pressure in the transfer chamber is made larger than the pressure in the second reaction chamber. A method of manufacturing a semiconductor device. Communicating the first reaction chamber with the transfer chamber and transferring the substrate from the transfer chamber to the first reaction chamber;
Cutting the communication between the first reaction chamber and the transfer chamber and applying the first treatment to the substrate in the first reaction chamber;
A step of communicating the substrate subjected to the first treatment by communicating the first reaction chamber with the transfer chamber to the transfer chamber;
Disconnecting the communication between the first reaction chamber and the transfer chamber;
A step of communicating a substrate transferred to the transfer chamber by communicating the second reaction chamber with the transfer chamber to the second reaction chamber;
Cutting the communication between the second reaction chamber and the transfer chamber and applying the second treatment to the substrate in the second reaction chamber;
A step of transferring the substrate subjected to the second treatment by communicating the second reaction chamber to the transfer chamber from the second reaction chamber to the transfer chamber;
The communication between the second reaction chamber and the transfer chamber and a degree cross one Engineering,
When communicating at least each reaction chamber and the transfer chamber, the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber, the pressure in the transfer chamber is made larger than the pressure in the second reaction chamber, In order to transfer the substrate subjected to at least the second treatment from the second reaction chamber to the transfer chamber, the second reaction chamber and the transfer chamber are communicated with each other, and / or the second reaction chamber and the transfer chamber, A semiconductor device manufacturing method comprising: cycle-purging the inside of the transfer chamber after disconnecting the communication. Transferring the substrate from the transfer chamber to the first reaction chamber;
Applying the first treatment to the substrate in the first reaction chamber;
Transporting the substrate subjected to the first treatment to the transport chamber;
Transporting the substrate transported to the transport chamber to a second reaction chamber;
Applying a second treatment to the substrate in the second reaction chamber;
A step of transferring the substrate subjected to the second treatment from the second reaction chamber to the transfer chamber,
At least when the substrate is transferred through the transfer chamber, the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber, and the pressure in the transfer chamber is made larger than the pressure in the second reaction chamber. A method of manufacturing a semiconductor device. A first reaction chamber for performing a first treatment on a substrate;
A second reaction chamber for performing a second treatment on the substrate;
A transfer chamber communicating with each reaction chamber and transferring a substrate to and from each reaction chamber;
A first gate valve that opens and closes between the transfer chamber and the first reaction chamber;
A second gate valve that opens and closes between the transfer chamber and the second reaction chamber;
When opening / closing at least the first gate valve and / or the second gate valve, the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber, and the pressure in the transfer chamber is set in the second reaction chamber. A control device for controlling the pressure to be greater than the pressure;
A substrate processing apparatus comprising: A first reaction chamber for performing a first treatment on a substrate;
A second reaction chamber for performing a second treatment on the substrate;
A transfer chamber communicating with each reaction chamber and transferring a substrate to and from each reaction chamber;
A first gate valve that opens and closes between the transfer chamber and the first reaction chamber;
A second gate valve that opens and closes between the transfer chamber and the second reaction chamber;
When opening / closing at least the first gate valve and / or the second gate valve, the pressure in the first reaction chamber is made larger than the pressure in the transfer chamber, and the pressure in the transfer chamber is set in the second reaction chamber. Control for controlling the pressure to be greater than the pressure, and further control for performing cycle purge of the transfer chamber after at least the second gate valve is open and / or after the second gate valve is closed. Equipment,
A substrate processing apparatus comprising:

Images