CN115855141A - Wafer detection system and detection method - Google Patents

Abstract

Embodiments of the present application provide a wafer detection system and detection method. The wafer detection system includes: a suspension support device with a hollow base, and the suspension support device is used to provide magnetic force to the wafer, so that the wafer is suspended above the hollow base; The wafer has an opposite first surface and a second surface, and the first surface faces the suspension support device; the first optical detection module is used to provide the first incident light and receive the first incident light formed by reflecting the first surface through the first surface. A reflected light; the second optical detection module is used to provide the second incident light and receive the second reflected light formed by reflecting the second incident light through the second surface; the analysis module is based on the pair of the first incident light and the first reflected light The first surface is analyzed, and the second surface is analyzed based on the second incident light and the second reflected light. The embodiment of the present application can avoid frictional force between the wafer and the suspension support device, thereby preventing the wafer from being damaged.

Description

Wafer detection system and detection method

technical field

Embodiments of the present invention relate to the technical field of semiconductors, and in particular to a wafer inspection system and inspection method.

Background technique

In the manufacturing process of semiconductor devices, it is very important to measure and analyze the surface film layer of the wafer. The measurement includes the measurement of the thickness of the film layer, the measurement of the reflectivity of the film layer or the Measurement of surface flatness, etc.

In addition, the wafer includes a front side and a back side oppositely, and there is also a need to measure and analyze both the front side and the back side. The detection steps of the current detection system include: first place the back side of the wafer on the carrying surface of the detection system, and measure the surface film layer on the front side of the wafer; then clamp and flip the wafer, and place the front side of the wafer On the loading surface of the inspection system, the surface film layer measurement is performed on the back side of the wafer.

However, the current detection system has the problems of slow detection speed and easy damage to the wafer.

Contents of the invention

Embodiments of the present application provide a wafer inspection system and inspection method, which are beneficial to improving the inspection speed and avoiding damage to the wafer.

According to some embodiments of the present application, an embodiment of the present application provides a wafer inspection system on the one hand, including: a suspension support device with a hollow base, and the suspension support device is used to provide a magnetic force to the wafer, so that the wafer is suspended on the Above the hollow base, the wafer has an opposite first surface and a second surface, and the first surface faces the suspension support device; a first optical detection module, the first optical detection module is arranged on the Below the suspension support device, it is used to provide the first incident light passing through the hollow area of the hollow base, and receive the first reflected light formed by reflecting the first incident light through the first surface; the second optical detection module , the second optical detection module is disposed above the suspension support device, and is used to provide a second incident light and receive a second reflected light formed by reflecting the second incident light through the second surface; an analysis module, The analysis module analyzes the first surface based on the first incident light and the first reflected light, and analyzes the second surface based on the second incident light and the second reflected light .

In addition, the suspension support device includes: a permanent magnet structure, the permanent magnet structure is wound on the hollow base to form a permanent magnet area, and the permanent magnet area is located at the periphery of the hollow area; a magnetic force generating module and a power supply module, the magnetic force generation module is set on the hollow base, the power supply module is used to provide variable electrical signals to the magnetic force generation module, and the magnetic force generation module receives the electrical signals to generate magnetic force value Variable magnetic force; a float structure, the float structure is suspended above the hollow base under the action of the magnetic force, and is used to support the wafer; a position monitoring module, the position monitoring module is used to monitor the specific position of the float structure position, and generate a position signal; a control module, based on the position signal, the control module controls the magnitude of the electrical signal provided by the power supply module.

In addition, the magnetic force generation module includes: a plurality of exciting coils distributed at intervals, and the power supply module provides the electrical signal to each of the exciting coils respectively.

In addition, the control module includes: an amplifying unit for receiving the position signal and amplifying the position signal; a single chip microcomputer for generating an adjustment signal based on the amplified position signal, and the power supply module receives the position signal A signal is adjusted to adjust the magnitude of the electrical signal provided to the field coil at a corresponding location.

In addition, the permanent magnet region has a central axis, and a plurality of the excitation coils are uniformly distributed around the central axis.

In addition, the number of the exciting coils is four; and the four exciting coils are symmetrically arranged about the central axis.

Optionally, the float structure includes a plurality of floats, and each float is located directly above the corresponding excitation coil.

In addition, the permanent magnet structure is an annular permanent magnet.

In addition, the permanent magnet structure includes: a plurality of permanent magnet columns arranged at intervals, and the plurality of permanent magnet columns are arranged around the magnetic force generating module.

In addition, the suspension support device is used to control the suspension of the wafer on the suspension surface, and the suspension surface has a first direction and a second direction perpendicular to each other; the position monitoring module includes at least two Hall sensors, At least one of the Hall sensors is used to detect changes in the magnetic field in the first direction, and at least another Hall sensor is used to detect changes in the magnetic field in the second direction.

In addition, the permanent magnet region has a central axis perpendicular to the suspension surface, and at least two of the Hall sensors are arranged symmetrically along the central axis.

In addition, the first optical detection module includes: a first incident light source, the first incident light source is arranged under the hollow area, and is used to provide the first incident light; a half mirror is located at the first Between an incident light source and the hollow area, it is used to transmit the first incident light and reflect the first reflected light; the first light receiving unit is used to receive the light reflected by the half mirror the first reflected light.

In addition, the second optical detection module includes: a second incident light source, disposed above the hollow area, for providing the second incident light; a second light receiving unit, disposed above the hollow area, for receiving the second reflected light.

According to some embodiments of the present application, on the other hand, the embodiment of the present application also provides a detection method using the aforementioned wafer detection system, including: providing a wafer to be detected, the wafer has an opposite first surface and a second surface surface; using the floating support device, the wafer is suspended above the floating support device, and the first surface faces the floating support device; using the first optical detection module and the analysis module, Analyzing the performance of the first surface; using the second optical detection module and the analysis module to analyze the performance of the second surface.

In addition, analyzing the performance of the first surface includes: analyzing the reflectivity of the first surface; and/or analyzing the film thickness of the first surface.

In addition, analyzing the performance of the second surface includes: analyzing the reflectivity of the second surface; and/or analyzing the film thickness of the second surface.

The technical solutions provided by the embodiments of the present application have at least the following advantages:

The magnetic field force of the suspension support device places the wafer above the hollow base of the suspension support device, which ensures that there will be no mechanical friction between the wafer and the hollow base, thereby avoiding damage to the wafer caused by mechanical friction. The first optical detection module located under the suspension support device emits the first incident light, the first incident light passes through the hollow area of the hollow base and irradiates the first surface of the wafer, and the first incident light is reflected by the first surface of the wafer to form For the first reflected light, the analysis module analyzes the performance of the first surface of the wafer according to the information of the first incident light and the first reflected light, and obtains the analysis result of the first surface of the wafer; the second optical detection module emits the first light Two incident light, the second incident light is irradiated on the second surface of the wafer, the second incident light is reflected by the second surface of the wafer to form the second reflected light, and the analysis module analyzes the wafer according to the information of the second incident light and the second reflected light The performance of the second side of the wafer is analyzed, and the analysis results of the second side of the wafer are obtained. The first optical detection module and the second optical detection module independently detect the performance data of the first side of the wafer and the performance data of the second side of the wafer, which realizes the measurement of the first side of the wafer without turning over the wafer And the performance of the second side, which can not only improve the overall test efficiency of the wafer performance, but also avoid damage to the wafer during the flipping process.

Description of drawings

One or more embodiments are exemplified by the pictures in the corresponding drawings, and these exemplifications do not constitute a limitation to the embodiments. Elements with the same reference numerals in the drawings represent similar elements. Unless otherwise stated, the drawings in the drawings are not limited to scale.

FIG. 1 is a schematic diagram of a wafer detection system provided in an embodiment of the present application;

FIG. 2 is a top view of the suspension support device in the wafer inspection system provided by the embodiment of the present application;

FIG. 3 is a relational diagram of the constituent modules of the suspension support device in the wafer inspection system provided by the embodiment of the present application;

4 is a schematic diagram of the first structure of the permanent magnet in the wafer inspection system provided by the embodiment of the present application;

FIG. 5 is a schematic diagram of the second structure of the permanent magnet in the wafer inspection system provided by the embodiment of the present application;

6 is a schematic diagram of the third structure of the permanent magnet in the wafer inspection system provided by the embodiment of the present application;

FIG. 7 is a schematic structural diagram of a control module in a wafer detection system provided in an embodiment of the present application;

FIG. 8 is a schematic structural diagram of the first optical module and the second optical module in the wafer inspection system provided by the embodiment of the present application.

Detailed ways

The wafer detection system and detection method provided in the embodiments of the present application use the principle of magnetic levitation to separate the wafer from the hollow base of the suspension support device in space, which can effectively avoid friction between the wafer and the hollow base, Thereby preventing the wafer from being damaged. At the same time, under the suspension support device with a hollow base, a first optical detection module is arranged, the first optical detection module emits the first incident light and receives the first reflected light through the hollow area of the hollow base, and the analysis module according to the first An incident light and a first reflected light yield performance data on the first side of the wafer. In the process of measuring the first side of the wafer, the setting of the hollow base and the first optical detection module prevents the flipping action of the wafer, thereby protecting the wafer from friction damage caused by the flipping of the wafer, and improving the Measure efficiency.

Various embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. However, those of ordinary skill in the art can understand that in each embodiment of the application, many technical details are provided for readers to better understand the application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in this application can also be realized.

Referring to FIG. 1, the wafer detection system includes: a suspension support device 101 with a hollow base 106, the suspension support device 101 is used to provide a magnetic force to the wafer 102, so that the wafer 102 is suspended above the hollow base 106, and the wafer 102 has a relative The first surface 103 and the second surface 104 of the suspension support device 101, and the first surface 103 faces the suspension support device 101; the first optical detection module 105, the first optical detection module 105 is arranged under the suspension support device 101 for providing The first incident light 131 of the hollowed out area 107, and receive the first reflected light 133 formed by the reflection of the first incident light 131 through the first surface 103; the second optical detection module 108, the second optical detection module 108 is arranged on the suspension support device 101 above, used to provide the second incident light 136, and receive the second reflected light 138 formed by the reflection of the second incident light 136 through the second surface 104; the analysis module 109, the analysis module 109 is based on the first incident light 131 and the first reflected light The light 133 analyzes the first surface 103 and analyzes the second surface 104 based on the second incident light 136 and the second reflected light 138 .

The magnetic force provided by the suspension support device 101 suspends the wafer 102 in the air, thereby avoiding friction damage caused by friction between the wafer 102 and the suspension support device 101 . The second optical detection module 108 located above the wafer 102 analyzes the second surface 104 of the wafer 102; the first incident light 131 emitted by the first optical detection module 105 located below the wafer 102 is irradiated through the hollow area 107 On the first surface 103 of the wafer 102, a first reflected light 133 is formed, and the first reflected light 133 enters the first optical detection module 105 in the reverse direction through the hollow area 107, and the analysis module 109 The light 133 analyzes the first surface 103 of the wafer 102; through the setting of the hollow area 107 and the first optical detection module 105, the second surface 104 of the wafer 102 can be measured without flipping the wafer 102, which avoids The frictional damage caused to the wafer 102 during the flipping process of the wafer 102 improves the measurement efficiency.

Referring to FIG. 1 and FIG. 2, the plane passing through the dotted line AA' and parallel to the hollow base 106 is the suspended surface of the wafer 102, and the suspended support device 101 is used to control the suspension of the wafer 102 on the suspended surface, and the suspended surface has The first direction 11 and the second direction 12 are perpendicular to each other.

2 and 3, in some embodiments, the suspension support device 101 may include: a permanent magnet structure 110, the permanent magnet structure 110 is wound on the hollow base 106 to form a permanent magnetic area 111, and the permanent magnetic area 111 is located in the hollow area The periphery of 107; magnetic force generating module 113 and power supply module 114, magnetic force generating module 113 is arranged on the hollow base 106, power supply module 114 is used to provide variable electrical signal to magnetic force generating module 113, magnetic force generating module 113 receives electrical signal to generate The magnetic force with variable magnetic force; the float structure, the float structure is suspended above the hollow base 106 under the action of the magnetic force, and is used to support the wafer 102; the position monitoring module 115, the position monitoring module 115 is used to monitor the floating support device 101 The specific position of the upper wafer 102 and generate a position signal; the control module 116 , based on the position signal, the control module 116 controls the magnitude of the electrical signal provided by the power supply module 114 .

Specifically, the position monitoring module 115 detects the specific position of the wafer 102 suspended above the suspension support device 101, and generates a position signal; the control module 116 controls the electrical power provided by the power supply module 114 based on the position signal generated by the position monitoring module 115. The size of the signal; the power supply module 114 provides a variable electrical signal to the magnetic force generation module 113; the magnetic force generation module 113 generates a variable magnetic force according to the received electrical signal, and the float structure positioned above the suspension support device 101 is affected by the variable magnetic force Therefore, the position shift occurs, so that the position of the wafer 102 supported by the float structure shifts, so as to reach the designated position. Moreover, the float structure has magnetism, so that the float structure can be suspended in a stable position, so as to improve the position stability of the wafer 102 .

It should be noted that the suspension support device 101 can actively adjust the position of the wafer 102, such as adjusting the distance between the first surface 103 of the wafer 102 and the first optical detection module 105, and the distance between the second surface 104 and the second surface 104 of the wafer 102. The distance between the two optical detection modules 108 is to adjust the degree of inclination of the first surface 103 and the second surface 104 relative to the horizontal plane, or to adjust the first surface 103 and the second surface 104 to be parallel to the horizontal plane. Specifically, the adjustment of the position of the wafer 102 is realized by adjusting the position of the float structure.

The suspension support device 101 has a hollow base 106 , and the center of the hollow base 106 has a hollow area 107 , and the hollow area 107 faces the wafer 102 .

In some embodiments, the area of the hollowed out area 107 can be greater than the area of the first surface 103 of the wafer 102, that is, the projection of the wafer 102 on the suspended surface is located inside the projection of the hollowed out area 107 on the suspended surface, which is beneficial to the surface of the wafer 102. The range of position movement is large.

In some other embodiments, the area of the hollow area 107 may be smaller than the area of the first surface 103 of the wafer 102 , that is, the projection of the wafer 102 on the floating surface is located outside the projection of the hollow area 107 on the floating surface.

In some embodiments, the shape of the hollow area 107 is circular, and in other embodiments, the shape of the hollow area 107 may be square.

Referring to FIG. 4 , in some embodiments, the permanent magnet structure 110 is a ring-shaped permanent magnet. The ring-shaped permanent magnet 110 is located on the periphery of the hollow area 107, and the ring-shaped permanent magnet 110 encloses a hollow area, and the projected area of the hollow area on the suspension surface is larger than the projected area of the hollow area 107 on the suspension surface.

It is worth noting that, since the magnetic field lines of the ring permanent magnet 110 are closed inside the magnet, the central hollow part of the ring permanent magnet acts as a repulsive force, while at its edge it acts as an attraction force, which is conducive to making the ring permanent magnet 110 center The wafer 102 above the hollow part is subjected to a repulsive force, so as to prevent the suspension support device 101 from contacting the wafer 102 .

Referring to FIG. 5 , in some other embodiments, the permanent magnet structure 110 includes: a plurality of permanent magnet columns arranged at intervals, and the plurality of permanent magnet columns are arranged around the magnetic force generating module 113 . It is worth noting that a plurality of permanent magnet columns are evenly distributed on the periphery of the hollowed-out area 107, and each permanent magnet column has its own independent magnetic field. The multiple magnetic fields of the plurality of permanent magnet columns overlap each other to form an overall magnetic field, and the overall magnetic field The magnitude of the magnetic force on the wafer 102 can be changed by changing the magnetic field of the permanent magnet column, so as to control the position of the wafer 102 .

Referring to FIG. 6 , in some other embodiments, the permanent magnet structure 110 is a plurality of sector-shaped permanent magnets arranged at intervals.

It should be noted that the material of the permanent magnet structure 110 may be oxide magnet, rubber magnet, plastic magnet or alloy magnet.

In some embodiments, the magnetic force generation module 113 may include: a plurality of excitation coils distributed at intervals, and the power supply module 114 provides electrical signals to each excitation coil respectively. The electrical signals provided by the power supply module 114 to each excitation coil are independent of each other, and the electrical signals corresponding to each excitation coil can be different. Different electrical signals enable the permanent magnet structure 110 to generate different magnetic forces towards the wafer 102, Therefore, the position of the control wafer 102 changes.

A plurality of excitation coils can be symmetrically distributed in the permanent magnet area 111 , and the excitation coils can provide a stable and controllable magnetic field force for the wafer 102 . The permanent magnet region 111 has a central axis perpendicular to the suspension surface, as shown by the dotted line BB' in FIG. 1 , and a plurality of excitation coils are uniformly distributed around the central axis.

It should be noted that when the magnitude of the current flowing through the excitation coil changes, the magnetic force generated by the suspension support device 101 on the wafer 102 will change, thereby controlling the position of the wafer 102 to change.

In some embodiments, the number of excitation coils is four, and the four excitation coils are arranged symmetrically around the central axis.

In other embodiments, the number of exciting coils may be more than four.

In some embodiments, the float structure may be a permanent magnet structure.

In some embodiments, the float structure may include a plurality of floats 117, and each float 117 is located directly above a corresponding excitation coil. In this way, each excitation coil can adjust the position of the float 117 independently, so that the position of the supporting surface for supporting the wafer 102 formed by all the floats 117 can be adjusted more accurately; in addition, the quality of each float 117 is relatively small. Therefore, the gravity required to provide the magnetic force provided to the float 117 is relatively small, making it easier for the float 117 to be suspended directly above the hollow base 106 stably.

It can be understood that, in some other embodiments, the float structure can also be an annular permanent magnet structure.

Referring to FIG. 3 and FIG. 7, in some embodiments, the position monitoring module 115 may include at least two Hall sensors 123, wherein at least one Hall sensor 123 is used to detect changes in the magnetic field in the first direction 11, and at least another A Hall sensor 123 is used to detect changes in the magnetic field in the second direction 12 . Wherein, the first direction 11 may be the X direction, and the second direction 12 may be the Y direction, that is, the first direction 11 and the second direction 12 may be perpendicular to each other.

The working principle of the Hall sensor 123: The Hall sensor 123 located on the hollow base 106 senses the change of the external magnetic field caused by the float structure, thereby generating a corresponding position voltage signal or position current signal.

The generated position voltage signal or position current signal is used as an initial signal for adjusting the position of the float structure.

In some embodiments, the Hall sensor 123 may be an open-loop (direct discharge) sensor, and in other embodiments, the Hall sensor 123 may be a closed-loop (magnetic balance sensor).

In some embodiments, the number of Hall sensors 123 is two, which are respectively used to detect changes in the magnetic field in the first direction 11 and the second direction 12 . In other embodiments, the number of Hall sensors 123 may be greater than two.

Continuing to refer to FIG. 7 , the permanent magnet region 111 has a central axis perpendicular to the levitation plane, and at least two Hall sensors 123 are arranged symmetrically along the central axis. The symmetrically arranged Hall components are beneficial to eliminate the influence of various additional voltages on the Hall sensor signal, thereby ensuring the accuracy of position detection of the float structure.

With reference to Fig. 3 and Fig. 7, in some embodiments, control module 116 can comprise: amplifying unit 124, and amplifying unit 124 is used for generating position signal, and amplifies position signal; Single-chip microcomputer 125, single-chip microcomputer 125 is used for based on the amplified position signal An adjustment signal is generated, and the power supply module 114 receives the adjustment signal, so as to adjust the magnitude of the electrical signal provided to the excitation coil at the corresponding position.

The specific working process of the control module 116: when the support surface of the float structure used to support the wafer 102 deviates in the first direction 11, the Hall element detecting the first direction 11 detects the change of the magnetic field, and then sends the changed magnetic field signal Transform into an electrical signal, and transmit the electrical signal to the single-chip microcomputer 125, the single-chip microcomputer 125 calculates the adjustment value according to the electrical signal, and provides a certain voltage and the current flowing through the coil to the excitation coil in the first direction 11 according to the adjustment value, and the changed voltage and The current changes the magnetic force of the suspension support device 101 , and adjusts the specific position of the float structure, that is, adjusts the specific position of each float 117 , so that the wafer 102 is placed at the center of the hollow area 107 .

It should be noted that when the support surface of the float structure used to support the wafer 102 is displaced in the second direction 12, the specific working process of the control module 116 is similar to the situation in which the wafer 102 is displaced in the first direction 11, which is not mentioned here. Let me repeat.

The control module 116 can also control the float structure to be in different positions, so that the wafer 102 is in different positions, thereby measuring the performance of different positions of the wafer 102, and the control module 116 is connected with the wafer 102 without contact, which can avoid Wafer 102 is damaged by friction.

When the buoy structure is placed above the suspension support device 101, the center position of the buoy structure may not be aligned with the center position of the hollow area 107, so the position monitoring module 115, the control module 116, the power supply module 114 and the magnetic force generation module 113 need to be To achieve the function of correcting the position of the float structure, so as to correct the specific position of the wafer 102 .

8, the first optical detection module 105 may include: a first incident light source 130, the first incident light source 130 is arranged below the hollow area 107, for providing the first incident light 131; a half mirror 132, located in the first Between the incident light source 130 and the hollow area 107, it is used to transmit the first incident light 131 and reflect the first reflected light 133; the first incident light receiving unit 134 is used to receive the first incident light reflected by the half mirror 132 Reflected light 133 .

In some embodiments, the first optical detection module 105 may further include a first polarizer 142 , and the function of the first analyzer 142 is to measure changes in the amplitude and phase of the first reflected light 133 .

The half mirror 132 is divided into a light-transmitting part and a reflecting part. The function of the light-transmitting part is to convert the first incident light 131 emitted by the first incident light source 130 from a polarization state to a linearly polarized state. The function of the reflecting part is to transform the first incident light 131 The reflected light 133 is reflected to the first analyzer 142 .

Part of the incident light directed at the wafer film layer forms reflected light on the surface of the wafer film layer, and the other part of the incident light will pass through the film layer of the wafer 102 to form reflected light at the interface between the wafer film and the wafer 102 , the two parts of the reflected light form a light interference phenomenon, thereby measuring the performance data of the wafer film. Specifically, the amplitude and phase of the first incident light 131 and the first reflected light 133 are different, so as to measure the performance data of the first surface 103 of the wafer 102 .

It should be noted that the first incident light 131 irradiates the first surface 103 of the wafer 102 and is reflected as the first reflected light 133 , and the paths of the first incident light 131 and the first reflected light 133 are on the same plane.

The second optical detection module 108 may include: a second incident light source 135, disposed above the hollow area 107, for providing the second incident light 136; a second incident light receiving unit 137, disposed above the hollow area 107, for receiving the second incident light 136; Two reflected light 138 .

The second optical detection module 108 may also include a polarizer 140 and a second analyzer 141, the function of the polarizer 140 is to convert the second incident light 136 emitted by the second incident light source 135 from a polarization state to a linear polarization state, The function of the second analyzer 141 is to test the variation of the amplitude and phase of the second incident light 136 .

In some embodiments, a part of the incident light directed at the film layer of the wafer 102 forms reflected light on the surface of the film layer of the wafer 102, and another part of the incident light will pass through the film layer of the wafer 102, and the light between the film layer of the wafer 102 and the wafer The interface between the circles 102 forms reflected light, and the two parts of the reflected light form a light interference phenomenon, thereby measuring the performance data of the thin film of the wafer 102 . Specifically, the amplitude and phase of the second incident light 136 and the second reflected light 138 are different, so as to measure the performance data of the second surface 104 of the wafer 102 .

It should be noted that the second incident light 136 irradiates the second surface 104 of the wafer 102 to be emitted as the second reflected light 138 , and the paths of the first incident light 131 and the first reflected light 133 are on the same plane.

It is worth noting that the second incident light source 135 can emit light stably, because the stability of the light source has an important impact on the test, and an unstable light source will make the test invalid.

It should be noted that due to the refraction, reflection, projection, scattering of light and the geometric shape error of the wafer surface, the point/area thickness of the tested film is not equal to the average thickness of the film, so it is necessary to perform multiple tests on the film at different positions of the wafer. Measurements to obtain a more accurate wafer thickness value.

The positions of the first optical detection module 105 and the second optical detection module 108 relative to the hollow base 106 can remain unchanged, so the suspension support device 101 is controlled to control the rotation of the wafer 102 at any angle, and the required wafer 102 is tested multiple times. Location.

In some embodiments, the analysis module 109 may include a first analysis module 150 and a second analysis module 151, the first analysis module 150 analyzes the first surface 103 based on the first incident light 131 and the first reflected light 133, the second The analysis module 151 analyzes the second surface 104 based on the second incident light 136 and the second reflected light 138 .

In order to more clearly illustrate the wafer inspection system provided by the above embodiments, the wafer inspection system will be described below in conjunction with the working principle of the wafer inspection system:

Place the wafer 102 above the suspension support device 101, the Hall sensor 123 on the hollow base 106 detects the position signal of the wafer 102 along the first direction 11 and the second direction 12, and transmits the position signal to the microcontroller 125 , the single-chip microcomputer 125 controls the output electrical signal to the power supply module 114 according to the position signal, and the power supply module 114 transmits the variable electrical signal to the exciting coil, and the current passing through the exciting coil changes, so that the magnetic force received by the float structure changes to adjust The position of the float structure causes the position of the wafer 102 to shift, and then to a stable state of suspension.

After the wafer 102 is stably suspended, the first optical detection module 105 and the analysis module 109 detect and analyze the first surface 103 of the wafer 102 to obtain the performance data of the first surface 103 of the wafer 102; The detection module 108 and the analysis module 109 detect and analyze the second surface 104 of the wafer 102 to obtain performance data of the second surface 104 of the wafer 102;

Ellipsometry is used for wafer performance measurement. Ellipsometry is a very sensitive film property measurement technology. Its principle is to use the characteristics of different materials with different refractive indices. Specifically, the polarizer emits light The light is converted into linearly polarized light, and the linearly polarized light becomes elliptically polarized light after being reflected by the wafer surface, and finally the change of its amplitude and phase is measured by the analyzer.

To sum up, on the one hand, the suspension support device 101 has a magnetic force towards the wafer 102, so that the float structure is in a suspended state, and the wafer 102 is supported by the float structure. Through the setting of the hollow area 107 and the first optical detection module 105, The second surface 104 of the wafer 102 can be measured without flipping the wafer 102 , which avoids frictional damage to the wafer 102 during the flipping process of the wafer 102 and improves the measurement efficiency.

Correspondingly, another embodiment of the present application also provides a detection method using the wafer detection system provided in the foregoing embodiments. The detection method provided in the embodiment of the present application will be described in detail below with reference to the accompanying drawings.

Referring to FIG. 1 and FIG. 8, a wafer 102 to be detected is provided, and the wafer 102 has an opposite first surface 103 and a second surface 104; using the suspension support device 101, the wafer 102 is suspended above the suspension support device 101, and The first surface 103 faces the suspension support device 101 .

In some embodiments, the film layer on the surface of the wafer 102 may be a single crystal film, and in other embodiments, the film layer on the surface of the wafer 102 may be a polycrystalline film, a granular film, and an amorphous film.

Wafer 102 may be random access memory, flash memory, or image sensors.

The suspension support device 101 is perpendicular to the hollow base 106, and the float structure is suspended above the hollow base 106. The wafer 102 is supported by the float structure. The contact area between the float structure and the wafer 102 is small, which can prevent the suspension support device 101 from contacting the wafer. Friction is generated between the circles 102 , thereby causing damage to the surface of the wafer 102 . In addition, the hollow area 107 of the hollow base 106 can facilitate detection of the surface properties of the wafer 102 relative to the hollow base 106 .

The performance of the first surface 103 is analyzed by using the first optical detection module 105 and the first analysis module 150 .

In some embodiments, analyzing the performance of the first surface 103 includes analyzing the reflectivity and film thickness of the first surface 103 . In some other embodiments, analyzing the performance of the first surface 103 includes analyzing the reflectivity or film thickness of the first surface 103 .

It should be noted that the performance of the first surface 103 is analyzed, and the performance of the analyzed first surface 103 of the wafer 102 includes but not limited to reflectivity and film thickness. In other embodiments, the performance of the wafer 102 can be detected. Other parameters of the first surface 103, such as surface roughness, curvature, etc.

The performance of the second surface 104 is analyzed by using the second optical detection module 108 and the second analysis module 151 .

In some embodiments, analyzing the performance of the second surface 104 includes analyzing the reflectivity and film thickness of the second surface 104 . In other embodiments, analyzing the performance of the second surface 104 includes analyzing the reflectivity or film thickness of the second surface 104 .

It should be noted that the performance of the second surface 104 is analyzed, and the analyzed performance of the second surface 104 of the wafer 102 includes but not limited to reflectivity and film thickness. In other embodiments, the second surface of the wafer 102 can be detected 104 other parameters, such as surface roughness, curvature, etc.

In general, the suspension support device 101 uses the magnetic field force to place the wafer 102 above the hollow base 106, thereby preventing mechanical friction between the wafer 102 and the hollow base 106, causing surface damage to the wafer 102; During the test process, the performance of the first surface 103 and the second surface 104 of the wafer 102 are analyzed simultaneously by the first analysis module 150 and the second analysis module 151, which improves the overall test efficiency of the wafer 102. In addition, there is no need to Flipping the wafer 102 prevents the wafer 102 from being mechanically damaged during the flipping process.

Those of ordinary skill in the art can understand that the above-mentioned embodiments are specific examples for realizing the present invention, and in practical applications, various changes can be made to it in form and details without departing from the spirit and spirit of the present invention. scope. Any person skilled in the art can make respective changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention should be based on the scope defined in the claims.

Claims (16)

1. A wafer detection system, characterized in that, comprising: A suspension support device with a hollow base, the suspension support device is used to provide magnetic force to the wafer, so that the wafer is suspended above the hollow base, the wafer has opposite first and second surfaces, and the The first surface faces the suspension support device; A first optical detection module, the first optical detection module is arranged under the suspension support device, and is used to provide the first incident light passing through the hollow area of the hollow base, and receive the first incident light passing through the the first reflected light formed by the reflection of the first surface; The second optical detection module, the second optical detection module is arranged above the suspension support device, and is used to provide the second incident light and receive the second reflection formed by the second incident light reflected by the second surface Light; an analysis module, the analysis module analyzes the first surface based on the first incident light and the first reflected light, and analyzes the second surface based on the second incident light and the second reflected light face analysis. 2. The wafer inspection system according to claim 1, wherein the suspension support device comprises: A permanent magnet structure, the permanent magnet structure is wound around the hollow base to form a permanent magnet area, and the permanent magnet area is located on the periphery of the hollow area; A magnetic force generating module and a power supply module, the magnetic force generating module is arranged on the hollow base, the power supply module is used to provide a variable electrical signal to the magnetic force generating module, and the magnetic force generating module receives the electrical signal to Generate magnetic force with variable magnetic value; a float structure, the float structure is suspended above the hollow base under the action of the magnetic force, and is used to support the wafer; A position monitoring module, the position monitoring module is used to monitor the specific position of the buoy structure and generate a position signal; A control module, the control module controls the magnitude of the electrical signal provided by the power supply module based on the position signal. 3. wafer detection system as claimed in claim 2, is characterized in that, described magnetic force generation module comprises: There are a plurality of exciting coils distributed at intervals, and the power supply module provides the electrical signal to each of the exciting coils respectively. 4. wafer inspection system as claimed in claim 3, is characterized in that, described control module comprises: an amplifying unit, configured to receive the position signal and amplify the position signal; The single-chip microcomputer is used to generate an adjustment signal based on the amplified position signal, and the power supply module receives the adjustment signal to adjust the magnitude of the electrical signal provided to the exciting coil at a corresponding position. 5. The wafer inspection system according to claim 3, wherein the permanent magnet region has a central axis, and a plurality of the exciting coils are evenly distributed around the central axis. 6 . The wafer inspection system according to claim 5 , wherein the number of the excitation coils is four; and the four excitation coils are arranged symmetrically about the central axis. 7. The wafer inspection system according to claim 3, wherein the float structure comprises a plurality of floats, and each float is located directly above the corresponding excitation coil. 8. The wafer inspection system according to claim 2, wherein the permanent magnet structure is a ring-shaped permanent magnet. 9. The wafer inspection system according to claim 2, wherein the permanent magnet structure comprises: a plurality of permanent magnet columns arranged at intervals, and a plurality of the permanent magnet columns are arranged around the magnetic force generating module . 10. The wafer inspection system according to claim 2, wherein the suspension support device is used to control the suspension of the wafer on the suspension surface, and the suspension surface has a first direction and a second direction perpendicular to each other. Two directions; the position monitoring module includes at least two Hall sensors, wherein at least one of the Hall sensors is used to detect changes in the magnetic field in the first direction, and at least another of the Hall sensors is used to detect A change in the magnetic field in the second direction. 11. The wafer inspection system according to claim 10, wherein the permanent magnet region has a central axis perpendicular to the levitation surface, and at least two of the Hall sensors are arranged symmetrically along the central axis. 12. The wafer detection system according to claim 1, wherein the first optical detection module comprises: a first incident light source, the first incident light source is disposed under the hollowed-out area, and is used to provide the first incident light; a half-mirror, located between the first incident light source and the hollow area, for transmitting the first incident light and reflecting the first reflected light; The first light receiving unit is configured to receive the first reflected light reflected by the half mirror. 13. The wafer detection system according to claim 1, wherein the second optical detection module comprises: a second incident light source, disposed above the hollow area, for providing the second incident light; The second light receiving unit is arranged above the hollow area and used to receive the second reflected light. 14. A detection method utilizing the wafer detection system according to any one of claims 1-13, characterized in that, comprising: providing a wafer to be inspected, the wafer having opposing first and second sides; suspending the wafer above the suspension support device with the first surface facing the suspension support device; Analyzing the performance of the first surface by using the first optical detection module and the analysis module; The performance of the second surface is analyzed by using the second optical detection module and the analysis module. 15. The detection method according to claim 14, wherein analyzing the performance of the first surface comprises: analyzing the reflectivity of the first surface; And/or, analyze the film thickness of the first surface. 16. The detection method according to claim 14, wherein the performance analysis of the second surface comprises: analyzing the reflectivity of the second surface; And/or, analyze the film thickness of the second surface.

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