Wafer processing apparatus

Abstract

The application relates to a wafer processing device, comprising: a process chamber, having a light-transmitting part, a cavity wall, and a containing cavity formed by the cavity wall, the containing cavity having a bearing surface for placing a wafer, the light-transmitting part being arranged in the cavity wall; a detector arranged outside the process chamber and spaced apart from the light-transmitting part; the detector is used to emit incident light into the containing cavity through the light-transmitting part to obtain position information of the wafer on the bearing surface; an optical assembly arranged in the containing cavity; the optical assembly at least comprises a first optical component and a second optical component, the first optical component is used to convert the incident light into a first light path, the second optical component is used to convert the first light path into a second light path, and the second light path is collected by the detector through the light-transmitting part; the incident light, the first light path and the second light path pass through different positions of the bearing surface respectively. The application can detect the wafer position in the process chamber in real time, and avoid wafer deviation.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing technology, and more specifically to a wafer processing device. Background Technology

[0002] In the semiconductor manufacturing industry, wafers are transferred between process chambers and transport chambers. It is necessary to ensure that the wafers are placed accurately after arriving at the worktable in the process chamber to avoid misalignment, especially in plasma-enhanced chemical vapor deposition processes.

[0003] Plasma-enhanced chemical vapor deposition is a commonly used thin film deposition technology in the semiconductor industry. In this process, if the wafer deviates after arriving at the worktable, it will directly lead to uneven plasma distribution during the process, resulting in uneven film thickness, edge defects, and ultimately wafer scrap.

[0004] In related technologies, in order to ensure the positional accuracy of the wafer, sensors are often set at the loading plane of the transfer chamber. However, the sensors can only detect the position when the wafer enters or leaves the transfer chamber, which has low timeliness. Alternatively, the wafer position can be detected after the process is completed, which has a lag and cannot detect the wafer offset in time, which greatly affects the product yield. Utility Model Content

[0005] The technical problem to be solved by this application is to provide a wafer processing device that can detect the wafer position in real time within the process chamber to avoid wafer misalignment.

[0006] According to an embodiment of this application, a wafer processing apparatus is provided, comprising: a process chamber having a light-transmitting portion, a chamber wall, and a receiving cavity formed by the chamber wall, the receiving cavity having a support surface for placing a wafer, the light-transmitting portion being disposed in the chamber wall; the light-transmitting portion being disposed in the chamber wall; a detector being disposed outside the process chamber and spaced apart from the light-transmitting portion; the detector being used to emit incident light that passes through the light-transmitting portion and enters the receiving cavity to obtain position information of the wafer on the support surface; an optical assembly being disposed in the receiving cavity; the optical assembly comprising at least a first optical element and a second optical element, the first optical element being used to convert the incident light to form a first optical path, the second optical element being used to convert the first optical path to form a second optical path, and the second optical path passing through the light-transmitting portion and being collected by the detector; wherein the incident light, the first optical path, and the second optical path respectively pass through different positions on the support surface.

[0007] In one embodiment, the first optical element and the second optical element are disposed on the cavity wall, and the mounting positions on the cavity wall satisfy the following: the incident angle of the incident light at the first optical element is an acute angle; the incident angle of the first optical path at the second optical element is an acute angle.

[0008] In one embodiment, the cavity wall includes two opposing first sidewalls and a second sidewall intersecting one of the first sidewalls; the light-transmitting portion and the first optical element are respectively located on the two first sidewalls, and the light-transmitting portion and the first optical element are opposite to each other; the second optical element is disposed on the second sidewall.

[0009] In one embodiment, the process chamber is provided with two support surfaces for supporting the wafer, and the optical components are provided in two sets, each set corresponding to one of the support surfaces, and each set includes the first optical element and the second optical element.

[0010] In one embodiment, the two bearing surfaces are located on opposite sides of the incident light transmission direction.

[0011] In one embodiment, the wafer processing apparatus further includes a transfer chamber for transferring wafers, the transfer chamber being connected to the cavity wall, and a delivery port communicating with the receiving cavity is provided at the connection between the transfer chamber and the cavity wall.

[0012] In one embodiment, multiple process chambers are provided, and all process chambers are arranged sequentially around the transmission chamber; each process chamber is correspondingly provided with the detector and the optical component.

[0013] In one embodiment, the wafer processing equipment further includes a clamping device disposed in the transfer chamber, adapted to clamp the wafer and move the wafer between the transfer chamber and each of the process chambers.

[0014] In one embodiment, the wafer processing equipment further includes an alarm device connected to the detector, which is used to issue an electro-optical alarm or an audible alarm when the detector detects a wafer offset.

[0015] In one embodiment, the wafer processing equipment further includes a control system connected to the detector, the control system being used to generate alarm information based on the wafer's position information, or to control the wafer processing steps based on the wafer's position information.

[0016] Compared with the prior art, the beneficial effects of this application are as follows: By setting a detector and setting a light-transmitting part on the cavity wall at the position corresponding to the detector, the detector can smoothly emit incident light into the cavity. After the incident light is reflected by the optical components, it forms a first optical path and a second optical path and is received by the detector. The incident light, the first optical path and the second optical path all pass through the carrier surface, i.e., the area where the wafer is located, thereby obtaining the wafer's position information and realizing real-time position monitoring of the wafer. This ensures that the wafer is always in a standard position during processes such as thin film deposition, avoiding wafer position deviation and affecting product yield. When the wafer is placed on the carrier surface in the process cavity, the problem of wafer deviation can be detected in time, which is highly efficient. Moreover, the detection process can be carried out synchronously with the process flow without interrupting the process flow or waiting for the process flow to end, thereby improving product yield. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a process chamber according to an exemplary embodiment; Figure 2 It has Figure 1 A schematic diagram of the wafer processing equipment in the process chamber shown.

[0018] Explanation of reference numerals in the attached figures 1. Process chamber; 11. Chamber wall; 111. First side wall; 112. Second side wall; 12. Receiving cavity; 2. Supporting surface; 3. Transmitting part; 4. Detector; 41. Incident light; 5. First optical element; 51. First optical path; 6. Second optical component; 61. Second optical path; 7. Transmission chamber; 8. Clamping device; 81. Base; 82. Robotic arm. Detailed Implementation

[0019] Unless otherwise defined, the technical or scientific terms used in this specification and claims shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. Specific embodiments of this application will be described below in conjunction with the accompanying drawings. It should be noted that, in order to provide a concise description, this specification cannot exhaustively describe all features of the actual embodiments. Without departing from the spirit and scope of this application, those skilled in the art can modify and substitute the embodiments of this application, and the resulting embodiments are also within the protection scope of this application.

[0020] In semiconductor processes such as thin-film deposition, the positioning accuracy of the wafer on the worktable directly affects product quality. Semiconductor process chambers are all sealed, making it impossible to manually observe the wafer's placement. Currently, whether the wafer's position has shifted is mainly determined by detecting the wafer's center information during transport, but this method is not timely and cannot provide early warnings.

[0021] To address the aforementioned technical problems, this application provides a wafer processing device that can detect the wafer position in real time within the process chamber, thereby preventing wafer misalignment.

[0022] refer to Figure 1 and Figure 2 The wafer processing equipment includes a process chamber 1, a detector 4, and an optical assembly. The process chamber 1 has a light-transmitting portion 3, a chamber wall 11, and a receiving cavity 12 enclosed by the chamber wall 11. The receiving cavity 12 has a support surface 2 for placing the wafer, and the light-transmitting portion 3 is disposed within the chamber wall 11. The detector 4 is located outside the process chamber 1 and spaced apart from the light-transmitting portion 3; the detector 4 emits incident light 41 that passes through the light-transmitting portion 3 and enters the receiving cavity 12 to obtain the position information of the wafer on the support surface 2. The optical assembly is disposed within the receiving cavity 12; the optical assembly includes at least a first optical element 5 and a second optical element 6. The first optical element 5 converts the incident light 41 to form a first optical path 51, and the second optical element 6 converts the first optical path 51 to form a second optical path 61, such that the second optical path 61 passes through the light-transmitting portion 3 and is collected by the detector 4; wherein the incident light 41, the first optical path 51, and the second optical path 61 pass through different positions on the support surface 2.

[0023] In this embodiment, when the wafer is placed on the carrier surface 2 for processing, the incident light 41 enters the receiving cavity 12 through the light-transmitting part 3, and then undergoes optical path conversion within the receiving cavity 12 through the optical components. The converted optical path passes through different positions on the carrier surface 2, that is, the incident light 41, the first optical path 51 and the second optical path 61 pass through different positions on the carrier surface 2 respectively. Finally, the reflected light on the carrier surface 2 passes through the light-transmitting part 3 and returns to the external detector 4. When a wafer is placed on the bearing surface 2, it is known that the wafer size is similar to the size of the bearing surface 2. The incident light 41, the first optical path 51, and the second optical path 61 also pass through different areas of the wafer. Specifically, the incident light 41, the first optical path 51, and the second optical path 61 are tangent to or intersect with the wafer. Thus, the detector 4 can obtain the wafer's position information in real time with the incident light 41, the first optical path 51, and the second optical path 61, and compare it with the position information of the wafer in a standard position to determine whether the wafer has shifted. When it is determined that the wafer has shifted, it can be detected in time, and the wafer processing can be stopped immediately to avoid affecting product quality. This embodiment can detect the wafer position in the process chamber 1, which is highly efficient. The detection process can be carried out synchronously with the process flow without interrupting the process flow or waiting for the process flow to end. It can monitor the wafer position in real time, ensuring that the wafer maintains accurate position during the production process and improving product yield.

[0024] Specifically, the detector 4 described above is a sensor structure integrating an infrared light source and a receiver. It can be, but is not limited to, an integrated structure of a light source and an infrared camera. The incident light 41 is infrared light. The infrared camera is a device that uses invisible infrared light with wavelengths from 0.76 to 400 micrometers for imaging. The form of the light-transmitting part 3 matches the form of the detector 4. In this embodiment, the light-transmitting part 3 is a sapphire window that can transmit infrared light. The sapphire window is made of sapphire material and can stably transmit infrared light. The number of optical elements in the optical assembly is not limited to two; it can be three or more. This allows the incident light to undergo multiple path changes within the cavity, thereby forming multiple intersecting optical paths on the carrier surface 2, which facilitates the acquisition of the edge position of the wafer on the carrier surface 2. Each optical element (such as the first optical element 5 and the second optical element 6) can be, but is not limited to, a reflecting prism. The surface of the reflecting prism is coated with a dielectric film suitable for infrared light reflection. The first optical element 5 reflects the incident light to obtain the first optical path 51. The material of the reflecting prism can be, but is not limited to, sapphire. Sapphire has high hardness, stable chemical properties, and is also resistant to high temperatures and corrosion, making it suitable for long-term stable operation in the high-temperature, high-vacuum, and clean environment of wafer processing equipment.

[0025] Furthermore, the principle of the detector 4 in this embodiment acquiring the wafer contour image is as follows: the light source (such as an infrared LED or a laser diode) in the detector 4 emits infrared light, which enters the process chamber 1 through the light-transmitting part 3. After two or more optical path conversions, such as multiple reflections, it is received by the receiver (such as an infrared camera) in the detector 4 outside the chamber. The incident light 41 is typically a fan-shaped beam with a certain divergence angle or a collimated surface light / structured light. The incident light 41, the first optical path 51, and the second optical path 61 pass through the wafer, allowing the detector 4, such as an infrared camera, to directly receive the entire light field information reflected from the wafer surface, thereby obtaining a wafer image. The detector 4 can compare the obtained wafer image with a stored wafer standard image to identify whether the wafer has shifted using existing image algorithms. Furthermore, the detector 4 extracts wafer edge information from the wafer image and compares it with standard edge information in the wafer standard image. This allows the detector to obtain the specific wafer offset using existing software algorithms, which can be used as wafer position adjustment data for position calibration or as calibration data for subsequent wafer delivery.

[0026] In this embodiment, incident light is emitted into the process cavity by detector 4, and then the incident light is transmitted in multiple paths within the cavity through optical components. This allows detector 4 to obtain the light field information of the entire bearing surface within the cavity, thus enabling real-time acquisition of images of the wafer within the process cavity. This allows for real-time monitoring of the wafer's position, ensuring that the wafer remains in a standard position during critical processes such as thin film deposition, preventing wafer position deviation and affecting product yield. In this embodiment, the wafer position can be monitored in real time, which is highly efficient. Furthermore, the detection process can be performed synchronously with the process flow without interrupting the process or waiting for the process to finish, thereby improving product yield.

[0027] In one specific embodiment, the first optical element 5 and the second optical element 6 are disposed on the cavity wall 11, and their installation positions on the cavity wall 11 satisfy the following conditions: the incident angle of the incident light 41 at the first optical element 5 is an acute angle; the incident angle of the first optical path 51 at the second optical element 6 is an acute angle. In this embodiment, the installation positions of the first optical element 5 and the second optical element 6 are defined so that the incident light 41 illuminates as large a range as possible within the receiving cavity 12, thereby increasing the area collected by the detector 4, such as covering the entire bearing surface 2 to obtain the complete contour information of the wafer, and improving the detection accuracy.

[0028] In one specific embodiment, the cavity wall 11 includes two opposing first sidewalls 111 and a second sidewall 112 intersecting one of the first sidewalls 111; the light-transmitting part 3 and the first optical element 5 are respectively located on the two first sidewalls 111, and the light-transmitting part 3 and the first optical element 5 are opposite to each other; the second optical element 6 is disposed on the second sidewall 112. In this embodiment, the cavity wall 11 may be a polygonal structure, with the light-transmitting part 3 and the first optical element 5 respectively mounted on the two opposing first sidewalls 111, and the second optical element 6 disposed on the second sidewall 112 intersecting the first sidewall 111. This facilitates the entry and reflection of incident light 41, forming multiple light paths within the cavity 12, thereby fully covering the bearing surface 2 and facilitating the acquisition of all light field information fed back from the wafer surface to obtain the entire outline image of the wafer.

[0029] Specifically, the first optical element 5 and the second optical element 6 can be installed on the cavity wall 11 by means of, but not limited to, embedded or protruding installation using a mounting base. Embedded installation means that the first optical element 5 is fixed in the mounting hole of the cavity wall 11 using a mounting base; protruding installation means that the first optical element 5 is fixed on the surface of the cavity wall 11 using a mounting base, so that the first optical element 5 protrudes relative to the cavity wall 11. Both embedded and protruding installation methods are conventional settings and will not be described in detail here.

[0030] In one specific embodiment, the process chamber 1 has two parallelly arranged support surfaces 2, each capable of supporting one wafer. The aforementioned optical components are provided in two sets, each set corresponding to one support surface 2, and each set includes a first optical element 5 and a second optical element 6. In this embodiment, the process chamber 1 can simultaneously produce two wafers. By setting two sets of optical components corresponding to the two support surfaces 2, the position of each wafer can be detected separately. Furthermore, each set of optical components forms an independent optical path to illuminate each support surface 2, avoiding mutual interference and ensuring the accuracy of wafer position detection.

[0031] Specifically, in each process chamber 1, two sets of optical components are symmetrically arranged and correspond to two bearing surfaces 2 respectively; wherein, two first optical elements 5 are spaced apart on the first sidewall 111 opposite to the light-transmitting part 3, and two second optical elements 6 can be arranged opposite each other, such as being installed on two opposite second sidewalls 112 in the chamber wall 11 respectively, so that the two sets of optical paths do not overlap in space and avoid mutual interference.

[0032] In one specific embodiment, the two bearing surfaces 2 are located on opposite sides of the transmission direction of the incident light 41. In this embodiment, the positions of the detector 4 and the light-transmitting part 3 can be configured such that the center of the light-transmitting part is on the symmetrical center line of the two bearing surfaces, so that the incident light 41 passes between the two bearing surfaces 2. In conjunction with the two sets of optical components, the position detection of two wafers can be realized simultaneously, improving the utilization rate of the detector 4 and the light-transmitting part 3 and reducing production costs.

[0033] In one specific implementation, reference is made to... Figure 2 The wafer processing equipment also includes a transfer chamber 7 for transporting wafers. The transfer chamber 7 is connected to the cavity wall 11, and a transport port (not shown) communicating with the receiving cavity 12 is provided at the connection between the transfer chamber 7 and the cavity wall 11. In this embodiment, the transfer chamber 7 is connected to the first side wall 111 where the first optical element 5 is located. A transport port is provided on the first side wall 111, and the transport port is connected to the receiving cavity 12 so that the wafer can enter and exit the process chamber 1 through the transport port. The transport port is spaced apart from the first optical element 5 to avoid interference. The transport port can be opened and closed so as to maintain the sealed environment of the process chamber 1 during the wafer production process.

[0034] In one specific embodiment, multiple process chambers 1 are provided, and all process chambers 1 are arranged sequentially around the transmission chamber 7; each process chamber is correspondingly provided with the detector and the optical component. In this embodiment, reference... Figure 2 All process chambers 1 are provided with, but not limited to, two bearing surfaces 2, and each bearing surface 2 has an independent optical component. The same process chambers can share a detector, so that all process chambers 1 can perform wafer position detection, thereby improving the wafer position detection efficiency and processing capability of the wafer processing equipment. All process chambers 1 are arranged around the transfer chamber 7, which facilitates the transfer of wafers between different process chambers 1 and further improves production efficiency.

[0035] In one specific implementation, reference is made to... Figure 2 The wafer processing equipment also includes a clamping device 8, which is located within the transfer chamber 7 and is suitable for clamping the wafer and moving it between the transfer chamber 7 and each process chamber 1. (Reference) Figure 2 The clamping device 8 includes a base 81 and a robotic arm 82 rotatably connected to the base 81. The robotic arm 82 is adapted to clamp the wafer. In this embodiment, the robotic arm 82 clamps the wafer and moves it between the transfer chamber 7 and each process chamber 1. The robotic arm 82 can move in the direction of entering or exiting each process chamber 1, and the rotation range of the robotic arm 82 covers all process chambers 1, ensuring that the wafer can accurately enter the target chamber. The base 81 is fixed to the bottom of the transfer chamber 7, providing stable support and ensuring that the robotic arm 82 maintains smooth operation during movement.

[0036] In one specific embodiment, the wafer processing equipment further includes an alarm device (not shown), which is connected to the detector 4 and is used to issue an electro-optical or audible alarm when the detector 4 detects a wafer displacement. When the detector 4 detects a wafer displacement, the detector 4 sends a command to the alarm device to trigger an alarm. Specifically, the alarm device is an alarm light or an audible alarm.

[0037] In one specific embodiment, the wafer processing equipment also includes a control system connected to the detector 4. The control system is used to generate alarm information based on the wafer's position information. In this embodiment, when the detector 4 detects a position shift of the wafer, the detector 4 sends a signal to the control system. The control system immediately issues an alarm and generates alarm information, which includes the wafer's shifted position, the time of occurrence, and the corresponding process chamber 1. Production personnel can then adjust the wafer position to avoid affecting product quality due to wafer position deviation. The process of the control system generating alarm information is conventional control logic and will not be described in detail here. The control system can also be used to control the wafer processing steps based on the wafer's position information. For example, when the control system receives a signal indicating a wafer shift, it can control the process equipment to stop working and control subsequent wafers to stop being transported, in order to prevent the wafer from being processed and scrapped.

[0038] The above description of the embodiments is intended to enable those skilled in the art to understand and apply this application. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without creative effort. Therefore, this application is not limited to the embodiments described herein, and any improvements and modifications made by those skilled in the art based on the disclosure of this application without departing from the scope and spirit of this application are within the scope of this application.

Claims

1. A wafer processing apparatus, comprising: A process chamber has a light-transmitting part, a chamber wall, and a receiving cavity formed by the chamber wall. The receiving cavity has a support surface for placing wafers, and the light-transmitting part is disposed in the chamber wall. A detector is placed outside the process chamber and spaced apart from the light-transmitting part; the detector is used to emit incident light that enters the receiving cavity through the light-transmitting part in order to obtain the position information of the wafer on the support surface; An optical component is placed in the receiving cavity; the optical component includes at least a first optical element and a second optical element, the first optical element is used to convert the incident light to form a first optical path, the second optical element is used to convert the first optical path to form a second optical path, and the second optical path passes through the light-transmitting part and is collected by the detector; The incident light, the first optical path, and the second optical path pass through different positions on the bearing surface.

2. The wafer processing equipment as described in claim 1, characterized in that, The first optical element and the second optical element are disposed on the cavity wall, and their installation positions on the cavity wall satisfy the following condition: the incident angle of the incident light at the first optical element is an acute angle; The angle of incidence of the first optical path at the second optical element is an acute angle.

3. The wafer processing equipment as described in claim 1, characterized in that, The cavity wall includes two opposing first sidewalls and a second sidewall that intersects with one of the first sidewalls; The light-transmitting part and the first optical element are respectively located on two first sidewalls, and the light-transmitting part and the first optical element are arranged opposite to each other; The second optical element is disposed on the second sidewall.

4. The wafer processing equipment as described in claim 1, characterized in that, The process chamber is provided with two support surfaces for supporting the wafer. The optical components are provided in two sets, each set corresponding to one of the support surfaces, and each set includes the first optical component and the second optical component.

5. The wafer processing equipment as described in claim 4, characterized in that, The two bearing surfaces are located on opposite sides of the incident light transmission direction.

6. The wafer processing equipment as described in claim 1, characterized in that, The wafer processing equipment further includes a transfer chamber for transferring wafers, the transfer chamber being connected to the cavity wall, and a delivery port communicating with the receiving cavity is provided at the connection between the transfer chamber and the cavity wall.

7. The wafer processing equipment as described in claim 6, characterized in that, The process chambers are provided in multiple ways, and all the process chambers are arranged sequentially around the transmission chamber; each process chamber is provided with the detector and the optical components.

8. The wafer processing equipment as described in claim 7, characterized in that, The wafer processing equipment further includes a clamping device disposed in the transfer chamber, which is adapted to clamp the wafer and drive the wafer to move between the transfer chamber and each of the process chambers.

9. The wafer processing equipment as described in claim 1, characterized in that, The wafer processing equipment also includes an alarm device connected to the detector, which is used to issue an electro-optical alarm or an audible alarm when the detector detects that the wafer has shifted.

10. The wafer processing equipment as described in claim 1, characterized in that, The wafer processing equipment also includes a control system connected to the detector. The control system is used to generate alarm information based on the wafer's position information, or to control the wafer processing steps based on the wafer's position information.

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