CN116065232A - MOCVD reaction cavity and material growth method - Google Patents

Abstract

The MOCVD reaction cavity and the material growth method provided by the application comprise the following steps: the reaction chamber body, set up in exhaust ring, laser unit and laser control unit in the reaction chamber body, the exhaust ring includes outer exhaust ring and cover establish the interior exhaust ring of outer exhaust ring, install on the interior surface of interior exhaust ring laser unit, the internally mounted of outer exhaust ring has laser control unit, laser unit's laser has ultraviolet and infrared two wave bands, laser control unit is used for controlling laser switch, laser power and facula size, above-mentioned MOCVD reaction chamber and material growth's method, through surveying substrate surface temperature, simultaneously, feed back this temperature signal to laser control unit, laser control unit changes the size of laser facula and laser power's size according to the analysis result, and then realizes the purpose of improving the growth temperature of reaction chamber and the homogeneity of temperature field, finally improves epitaxial material's crystal quality, not only can realize high-efficient p type doping, but also can realize accurate accuse temperature simultaneously, improves equipment's temperature field homogeneity and material's growth temperature.

Description

A kind of MOCVD reaction chamber and method for material growth

technical field

The present application relates to the technical field of semiconductor material preparation, in particular to an MOCVD reaction chamber and a material growth method.

Background technique

Ultraviolet disinfection technology has aroused greater market demand due to its advantages such as broad-spectrum efficiency, safety and environmental protection, no chemical residues, and easy operation. However, the preparation and application of AlGaN-based optoelectronic devices working in the deep ultraviolet (DUV) and far-ultraviolet bands are more limited. The main problem is that it is difficult to obtain high-quality AlGaN and AlGaN-based materials are difficult to achieve efficient p-type doping, The activation energy of Mg in AlGaN is as high as 150-510meV, so that the hole concentration at room temperature is very low, and only a small amount of Mg can be activated.

Metal Organic Chemical Vapor Deposition (MOCVD) is one of the most widely used methods for growing III-nitride thin films. The temperature of MOCVD equipment generally reaches 1200 degrees, and the performance of each component of the heating system in the reaction chamber is close to the limit.

Contents of the invention

Based on this, the present invention aims at the technical defects existing in the prior art, and provides a kind of MOCVD reaction chamber and material growth that can not only increase the growth temperature of the reaction chamber, but also realize the uniform and precise control of the temperature, and improve the crystal quality of the material. method, in order to achieve the above object, the technical scheme adopted by the application is as follows:

One of the purposes of the present application is to provide a MOCVD reaction chamber, including: a reaction chamber body, an exhaust ring arranged in the reaction chamber body, a laser unit and a laser control unit, and the exhaust ring includes an outer exhaust ring and an inner exhaust ring sleeved with the outer exhaust ring, the laser unit is installed on the inner surface of the inner exhaust ring, the laser control unit is installed inside the outer exhaust ring, the The laser of the laser unit has two bands of ultraviolet and infrared, and the laser control unit is used to control the switch of the laser, laser power, and spot size.

In some of the embodiments, the thickness ratio of the inner exhaust ring to the outer exhaust ring is in the range of 0.2-1.

In some of these embodiments, a linkage device is provided on the outer exhaust ring so that the exhaust ring and the outer exhaust ring move simultaneously.

In some of these embodiments, the outer exhaust ring is made of stainless steel, and the inner exhaust ring is composed of two 1/2 arcs.

In some of these embodiments, the cooling water of the inner exhaust ring and the outer exhaust ring can be shared, or can be divided into two channels of cooling water. When shared, the inner exhaust ring is water inflow, and the outer exhaust ring The ring is the water outlet.

In some of these embodiments, the outer surface of the laser control unit is further provided with a protective cover.

In some of these embodiments, there are several laser units, which are symmetrically distributed on the inner surface of the inner exhaust ring, and the longitudinal distribution range of the laser units on the inner exhaust ring is 1- 10mm.

In some of these embodiments, the infrared band in the laser unit can be used to detect the temperature of the substrate surface; at the same time, the temperature signal is fed back to the analysis unit of the laser control unit, and the analysis unit feeds back the analysis result to the A laser control unit, the laser control unit changes the size of the laser spot and the laser power according to the analysis result.

In some of the embodiments, the ultraviolet laser has a wavelength range of 200nm-360nm, and the infrared laser has a wavelength range of 630nm-1000nm.

The second purpose of the present application is to provide a method for material growth based on the MOCVD reaction chamber, comprising the following steps:

Transport the graphite disc with the substrate into the MOCVD reaction chamber;

After the monitoring temperature T0 of the MOCVD reaction chamber is higher than 600°C, the MOCVD reaction chamber turns on the infrared light source in the laser unit, starts the real-time temperature monitoring function, and the detected temperatures are respectively marked as T1/T2/T3;

When one of T1/T2/T3 is ≥1000°C, the laser control unit turns on the infrared heating function of the laser unit;

When the laser control unit monitors that the growth temperature is lower than 1000°C, the infrared heating function in the laser unit is turned off, and only the real-time temperature detection function is turned on;

After the process reaches the p-AlGaN layer, turn on the ultraviolet light source in the laser unit;

After the temperature of T0/T1/T2/T3 is lower than 600°C, turn off the ultraviolet light source in the laser unit;

When T0 is lower than 500°C, the laser control unit is turned off.

The application adopts the above-mentioned technical scheme, and its beneficial effects are as follows:

The MOCVD reaction chamber and the method for material growth provided by the application include: a reaction chamber body, an exhaust ring arranged in the reaction chamber body, a laser unit and a laser control unit, and the exhaust ring includes an outer exhaust ring and an outer exhaust ring. The inner exhaust ring of the outer exhaust ring is sleeved, the laser unit is installed on the inner surface of the inner exhaust ring, the laser control unit is installed inside the outer exhaust ring, and the laser The laser of the unit has two bands of ultraviolet and infrared. The laser control unit is used to control the switch, laser power, and spot size of the laser. The above-mentioned MOCVD reaction chamber and the method of material growth detect the substrate surface temperature and , the temperature signal is fed back to the laser control unit, and the laser control unit changes the size of the laser spot and the laser power according to the analysis results, thereby achieving the purpose of improving the growth temperature of the reaction chamber and the uniformity of the temperature field, and finally improving the epitaxial material. Excellent crystal quality, not only can achieve efficient p-type doping, but also can achieve precise temperature control, improve the uniformity of the temperature field of the equipment and the growth temperature of the material.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the accompanying drawings that need to be used in the embodiments of the present application or in the description of the prior art. Obviously, the accompanying drawings described below are only of the present application For some embodiments, those of ordinary skill in the art can also obtain other drawings based on these drawings without creative effort.

FIG. 1 is a schematic structural diagram of the MOCVD reaction chamber provided in Example 1 of the present application.

FIG. 2 is a schematic structural diagram of the exhaust ring provided in Embodiment 1 of the present application.

FIG. 3 is a distribution diagram of the inner exhaust ring of the laser unit provided in Embodiment 1 of the present application.

FIG. 4 is a schematic flow chart of a method for activating a p-type dopant by the reaction chamber system provided in Embodiment 2 of the present application.

Detailed ways

Embodiments of the present application are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary, and are intended to explain the present application, and should not be construed as limiting the present application.

In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings , is only for the convenience of describing the present application and simplifying the description, but does not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present application, "plurality" means two or more, unless otherwise specifically defined.

In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Example 1

Please refer to FIG. 1 to FIG. 3, a schematic structural diagram of a MOCVD reaction chamber provided by the present application, including: a reaction chamber body 110, an exhaust ring 120 disposed in the reaction chamber body 110, a laser unit 130 and a laser control unit 140. The structure and implementation of each component will be described in detail below.

The exhaust ring 120 includes an outer exhaust ring 121 and an inner exhaust ring 122 covering the outer exhaust ring 121 .

In this embodiment, the ratio of the thickness of the inner exhaust ring 122 to the outer exhaust ring 121 ranges from 0.2 to 1.

In this embodiment, the outer exhaust ring 121 is provided with a linkage device so that the inner exhaust ring 122 and the outer exhaust ring 121 move simultaneously.

In this embodiment, the outer exhaust ring 121 is made of stainless steel, and the material of the inner exhaust ring 122 is not limited to stainless steel.

In this embodiment, the inner exhaust ring 122 is composed of two 1/2 arcs, which can be disassembled for easy maintenance and replacement.

In this embodiment, the cooling water of the inner exhaust ring 122 and the outer exhaust ring 121 can be shared, or can be divided into two channels of cooling water. The exhaust ring 121 is for water outlet.

The laser unit 130 is installed on the inner surface of the inner exhaust ring 122 .

In this embodiment, there are several laser units 130, which are symmetrically distributed on the inner surface of the inner exhaust ring 122, and the longitudinal distribution range of the laser units 120 on the inner exhaust ring 122 is 1 to 10mm.

The laser of the laser unit 130 has two wavelength bands, ultraviolet and infrared.

In this embodiment, the ultraviolet band in the laser unit 130 is used to activate the p-type dopant such as Mg. After activation by ultraviolet light, the activation energy of Mg can be reduced and the hole concentration can be increased. The infrared band in the laser unit has two main purposes: one is to detect the surface temperature of the substrate. At the same time, the temperature signal is fed back to the analysis unit of the laser control unit 140, and the analysis unit feeds back the analysis result to the control unit 140, and the control unit 140 changes the size of the laser spot and the laser power according to the analysis result, thereby realizing the improvement of the reaction chamber. The purpose of the uniformity of the growth temperature and the temperature field, and finally improve the crystal quality of the epitaxial material.

In this embodiment, the ultraviolet laser has a wavelength range of 200 nm to 360 nm, and the infrared laser has a wavelength range of 630 nm to 1000 nm.

The laser control unit 140 is installed inside the outer exhaust ring 121 . The laser control unit 140 is used to control the laser switch, laser power, and spot size.

In this embodiment, the laser control unit 140 is embedded in the outer exhaust ring 121, and there is a protective cover on the outside, which can control the switch, band selection, power level, etc. of the laser unit 130; in addition, the laser spot can also be adjusted. diameter, so that it can fully cover the substrate 150 on the graphite disk (the size of the substrate is not limited).

It can be understood that the laser unit 130 can measure the substrate surface temperature T1/T2/T3, and cooperate with the temperature detection system of the MOCVD equipment to realize precise temperature control of the equipment and increase the growth temperature of the material. The laser control unit 140 feeds back the detected substrate surface temperature signal to the analysis unit in the control unit, and the control unit 140 adjusts the infrared laser power and spot diameter according to the analysis results, maintains the uniformity of the temperature field, and improves the growth rate of the substrate surface. temperature.

The MOCVD reaction chamber provided by the above-mentioned embodiments of the present application detects the substrate surface temperature and at the same time feeds back the temperature signal to the laser control unit, and the laser control unit changes the size of the laser spot and the laser power according to the analysis results, thereby realizing The purpose of improving the growth temperature of the reaction chamber and the uniformity of the temperature field is to finally improve the crystal quality of the epitaxial material, which can not only achieve efficient p-type doping, but also achieve precise temperature control, improve the temperature field uniformity of the equipment and the growth temperature.

Example 2

Please refer to FIG. 4 , which is a flow chart of the steps of the method for material growth based on the MOCVD reaction chamber provided in this embodiment, including the following steps S110 to S170 , and the implementation of each step will be described in detail below.

Step S110: Transporting the graphite disk with the substrate into the MOCVD reaction chamber.

Specifically, transfer the graphite disk with the substrate into the reaction chamber, close the door valve of the reaction chamber, raise the exhaust ring to run the process program.

Step S120: After the monitoring temperature T0 of the MOCVD reaction chamber is higher than 600°C, the MOCVD reaction chamber turns on the infrared light source in the laser unit to start the real-time temperature monitoring function, and the detected temperatures are marked as T1/T2/ T3.

It can be understood that the laser control unit transmits the monitored temperature signal to the analysis unit.

Step S130: When one of T1/T2/T3 is greater than or equal to 1000° C., the laser control unit turns on the infrared heating function of the laser unit.

It can be understood that the growth temperature and the uniformity of the temperature field are improved by changing the laser power and spot size through the laser control unit.

Step S140: When the laser control unit monitors that the growth temperature is lower than 1000° C., turn off the infrared heating function in the laser unit, and only turn on the real-time temperature detection function.

Step S150: After the process reaches the p-AlGaN layer, turn on the ultraviolet light source in the laser unit.

It can be understood that after the process runs to the p-AlGaN layer, the ultraviolet light source in the laser unit is turned on to activate Mg in the p-AlGaN material, reduce the activation energy of Mg, and increase the hole concentration.

Step S160: After the temperatures of T0/T1/T2/T3 are all lower than 600° C., turn off the ultraviolet light source in the laser unit.

Step S170: Turn off the laser control unit when T0 is lower than 500°C.

In the method based on the MOCVD reaction chamber and material growth provided by the above-mentioned embodiments of the present application, by detecting the temperature of the substrate surface, at the same time, the temperature signal is fed back to the laser control unit, and the laser control unit changes the size of the laser spot and the laser The size of the power, and then achieve the purpose of improving the growth temperature of the reaction chamber and the uniformity of the temperature field, and finally improve the crystal quality of the epitaxial material. Temperature field uniformity and material growth temperature.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above are only preferred embodiments of the present application, and only specifically describe the technical principle of the present application. These descriptions are only for explaining the principle of the present application, and cannot be interpreted as limiting the protection scope of the present application in any way. Based on the explanations here, any modifications, equivalent replacements and improvements made within the spirit and principles of the application, and those skilled in the art who can think of other specific implementation methods of the application without creative work are all It should be included within the scope of protection of this application.

Claims (10)

1. A MOCVD reaction chamber, characterized in that, comprising: a reaction chamber body, an exhaust ring arranged in the reaction chamber body, a laser unit and a laser control unit, and the exhaust ring includes an outer exhaust ring and a sleeve The inner exhaust ring of the outer exhaust ring is provided, the laser unit is installed on the inner surface of the inner exhaust ring, the laser control unit is installed inside the outer exhaust ring, and the laser unit The laser has two bands of ultraviolet and infrared, and the laser control unit is used to control the switch, laser power, and spot size of the laser. 2 . The MOCVD reaction chamber according to claim 1 , wherein the thickness ratio of the inner exhaust ring and the outer exhaust ring is between 0.2 and 1. 3 . 3. The MOCVD reaction chamber according to claim 1, wherein a linkage device is provided on the outer exhaust ring so that the inner exhaust ring and the outer exhaust ring move simultaneously. 4. The MOCVD reaction chamber according to claim 1, wherein the outer exhaust ring is made of stainless steel, and the inner exhaust ring is composed of two 1/2 arcs. 5. MOCVD reaction chamber as claimed in claim 1, is characterized in that, the cooling water of described inner exhaust ring and outer exhaust ring can be shared, also can be divided into two-way cooling water, described interior exhaust when sharing The ring is water inlet, and the outer exhaust ring is water outlet. 6. The MOCVD reaction chamber according to claim 1, wherein a protective cover is further provided on the outer surface of the laser control unit. 7. MOCVD reaction chamber as claimed in claim 1, is characterized in that, described laser unit is several, and is symmetrically distributed on the inner surface of described inner exhaust ring, and described laser unit is arranged in the inner surface The longitudinal distribution on the gas ring ranges from 1 to 10 mm. 8. MOCVD reaction chamber as claimed in claim 1, is characterized in that, the infrared band in the described laser unit can be used for detecting substrate surface temperature; Simultaneously this temperature signal is fed back to the analyzing unit of described laser control unit, so The analysis unit feeds back the analysis result to the laser control unit, and the laser control unit changes the size of the laser spot and the laser power according to the analysis result. 9. The MOCVD reaction chamber according to claim 1, characterized in that the wavelength range of the ultraviolet laser is 200nm-360nm, and the wavelength range of the infrared laser is 630nm-1000nm. 10. a kind of method based on the material growth of MOCVD reaction chamber described in claim 1, is characterized in that, comprises the steps: Transport the graphite disc with the substrate into the MOCVD reaction chamber; After the monitoring temperature T0 of the MOCVD reaction chamber is higher than 600°C, the MOCVD reaction chamber turns on the infrared light source in the laser unit, starts the real-time temperature monitoring function, and the detected temperatures are respectively marked as T1/T2/T3; When one of T1/T2/T3 is ≥1000°C, the laser control unit turns on the infrared heating function of the laser unit; When the laser control unit monitors that the growth temperature is lower than 1000°C, the infrared heating function in the laser unit is turned off, and only the real-time temperature detection function is turned on; After the process reaches the p-AlGaN layer, turn on the ultraviolet light source in the laser unit; After the temperature of T0/T1/T2/T3 is lower than 600°C, turn off the ultraviolet light source in the laser unit; When T0 is lower than 500°C, the laser control unit is turned off.

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