Silicon wafer polishing apparatus and silicon wafer polishing method

Abstract

The application provides a silicon wafer polishing device and a silicon wafer polishing method, and relates to the technical field of semiconductors.The silicon wafer polishing device comprises a silicon wafer polishing pad, a silicon wafer carrier is arranged along the outer periphery of the silicon wafer polishing pad, a silicon wafer accommodating hole is arranged along the outer periphery of the silicon wafer carrier, a first positioning component is used for emitting a first positioning signal to the carrier positioning area of the silicon wafer polishing pad, the first positioning signal is used for detecting whether the position of the silicon wafer carrier on the silicon wafer polishing pad is correct, a polishing pad cleaning component is used for spraying cleaning liquid from the center of the silicon wafer polishing pad to the edge or from the edge of the silicon wafer polishing pad to the center, and a second positioning component is used for emitting a second positioning signal to the center of the silicon wafer polishing pad, and the second positioning signal is used for detecting whether the transmission path of the silicon signal passes through the silicon wafer carrier.The application can detect whether the placement position of the silicon wafer carrier on the silicon wafer polishing pad is correct, and can detect the radius of the silicon wafer polishing pad that is not covered by the silicon wafer carrier to perform cleaning.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a silicon wafer polishing apparatus and a silicon wafer polishing method. Background Technology

[0002] When polishing silicon wafers using existing double-sided polishing equipment, a wafer carrier needs to be placed on the lower polishing pad of the double-sided polishing equipment. During the polishing process, the silicon wafer is placed inside the wafer carrier, and the wafer carrier drives the silicon wafer to run on the polishing pad to achieve the polishing of the silicon wafer.

[0003] However, the current process of placing silicon wafers on wafer carriers is done manually, which may lead to deviations in the placement of the wafer carriers. If the wafer carriers are misplaced, it will affect the subsequent placement of silicon wafers, which in turn will affect the quality of the subsequent silicon wafer polishing. Furthermore, the misplacement of the wafer carriers will also affect the cleaning effect of the polishing pads, which will further affect the quality of the subsequent silicon wafer polishing. Summary of the Invention

[0004] This invention provides a silicon wafer polishing apparatus and a silicon wafer polishing method to solve the problems of poor silicon wafer polishing quality and poor polishing pad cleaning effect caused by the positional deviation of the wafer carrier on the polishing pad.

[0005] To address the aforementioned technical problems, embodiments of the present invention provide the following technical solutions:

[0006] In a first aspect, embodiments of the present invention provide a silicon wafer polishing apparatus, comprising:

[0007] A circular silicon wafer polishing pad is formed, wherein at least one circular silicon wafer carrier is disposed on the outer periphery of the silicon wafer polishing pad;

[0008] The silicon wafer carrier has at least one silicon wafer receiving hole along its outer periphery, the silicon wafer receiving hole being used to place a silicon wafer;

[0009] A first positioning component disposed on one side of the silicon wafer polishing pad is used to transmit a first positioning signal to the carrier positioning area of ​​the silicon wafer polishing pad. The carrier positioning area is the area on the silicon wafer polishing pad where the part of the silicon wafer carrier without the silicon wafer receiving hole is located when the silicon wafer carrier is correctly positioned. The first positioning signal is used to detect whether the position of the silicon wafer carrier on the silicon wafer polishing pad is correct.

[0010] A polishing pad cleaning assembly is disposed on one side of the silicon wafer polishing pad. The polishing pad cleaning assembly is used to clean the silicon wafer from the center of the silicon wafer polishing pad to the edge of the silicon wafer polishing pad or from the edge of the silicon wafer polishing pad to the center of the silicon wafer polishing pad.

[0011] A second positioning component is located at the same height as the silicon wafer carrier on the silicon wafer polishing pad and disposed on one side of the silicon wafer polishing pad. The second positioning component is used to transmit a second positioning signal to the center of the silicon wafer polishing pad. The second positioning signal is used to detect whether the signal transmission path passes through the silicon wafer carrier.

[0012] In some embodiments, the diameter of the silicon wafer carrier is smaller than the radius of the silicon wafer polishing pad;

[0013] The diameter of the silicon wafer receiving hole is smaller than the radius of the silicon wafer carrier;

[0014] The silicon wafer polishing pad is used to rotate around the center of the silicon wafer polishing pad.

[0015] In some embodiments, the first positioning component includes a first signal transmitter and a first signal receiver disposed on one side of the silicon wafer polishing pad;

[0016] The first signal transmitter is used to transmit the first positioning signal to the positioning area of ​​the carrier, and the first signal receiver is used to receive the first positioning signal and obtain the reflection result of the first positioning signal. The reflection result is used to indicate whether the position of the silicon wafer carrier on the silicon wafer polishing pad is correct.

[0017] The second positioning component includes a second signal transmitter, and the silicon wafer polishing apparatus further includes a second signal receiver;

[0018] The second signal receiver is disposed at the center of the silicon wafer polishing pad;

[0019] The second signal transmitter is used to transmit the second positioning signal to the center of the silicon wafer polishing pad, and the second signal receiver is used to receive the second positioning signal and obtain the reception result of the second positioning signal. The reception result is used to indicate whether the signal transmission path passes through the silicon wafer carrier.

[0020] In some embodiments, the first signal transmitter and the first signal receiver are connected by a swing arm;

[0021] The swing arm is used to drive the first signal transmitter to swing, or the swing arm is used to drive the first signal receiver to swing.

[0022] In some embodiments, the first signal transmitter and the second signal transmitter include at least one of the following:

[0023] Laser signal transmitter;

[0024] Infrared signal transmitter;

[0025] Ultrasonic signal transmitter;

[0026] The first signal receiver and the second signal receiver include at least one of the following:

[0027] Laser signal receiver;

[0028] Infrared signal receiver;

[0029] Ultrasonic signal receiver.

[0030] In some embodiments, the polishing pad cleaning assembly includes a mounting bracket, a telescopic tube, and a cleaning nozzle;

[0031] The first end of the telescopic tube is fixedly connected to the fixed bracket, and the second end of the telescopic tube is connected to the cleaning nozzle;

[0032] The telescopic tube is used to drive the cleaning nozzle to extend and retract along the radius of the silicon wafer polishing pad, and the cleaning nozzle is used to spray cleaning liquid onto the radius of the silicon wafer polishing pad;

[0033] The second positioning component is fixedly connected to the fixed bracket.

[0034] In a second aspect, embodiments of the present invention also provide a silicon wafer polishing method, applied to a silicon wafer polishing apparatus as described in any one of the first aspects, the method comprising:

[0035] Control the first positioning component to transmit a first positioning signal to the positioning area of ​​the vehicle, and receive the reflection result of the first positioning signal;

[0036] If the placement position of the silicon wafer carrier is determined to be correct based on the reflection results, the silicon wafer placement and silicon wafer polishing processes are performed.

[0037] After the silicon wafer polishing process is completed, the second positioning component is controlled to send the second positioning signal to the center of the silicon wafer polishing pad and receive the result of receiving the second positioning signal.

[0038] Based on the received result, the polishing pad cleaning assembly is controlled to spray cleaning fluid onto the radius of the silicon wafer polishing pad.

[0039] In some embodiments, controlling the first positioning component to transmit a first positioning signal to the vehicle positioning area includes:

[0040] Control the first signal transmitter to transmit the first positioning signal to the positioning area of ​​the vehicle;

[0041] The silicon wafer polishing pad is controlled to rotate by a first preset angle, and the first signal transmitter is returned to the step of transmitting the first positioning signal to the vehicle positioning area until the first signal transmitter is controlled to transmit at least two first positioning signals to the vehicle positioning area.

[0042] The reflection result of receiving the first positioning signal includes:

[0043] The reflection results of each of the first positioning signals are received sequentially by the first signal receiver.

[0044] The process of placing and polishing the silicon wafer after determining that the placement position of the silicon wafer carrier is correct based on the reflection result includes:

[0045] If the reflection result of each of the first positioning signals indicates that the first positioning signal is received by the first signal receiver after being reflected by the positioning area of ​​the carrier, it is determined that the silicon wafer carrier is correctly positioned on the silicon wafer polishing pad, and the silicon wafer is placed in the silicon wafer receiving hole for silicon wafer polishing process.

[0046] The control of the second positioning component to transmit the second positioning signal toward the center of the silicon wafer polishing pad includes:

[0047] Control the second signal transmitter to transmit the second positioning signal toward the center of the silicon wafer polishing pad;

[0048] The reception result of receiving the second positioning signal includes:

[0049] The reception result of the second positioning signal is received by the second signal receiver;

[0050] The step of controlling the polishing pad cleaning assembly to spray cleaning fluid onto the radius of the silicon wafer polishing pad based on the received result includes:

[0051] If the receiving result indicates that the second positioning signal was not transmitted through the silicon wafer carrier and was received by the second signal receiver, the polishing pad cleaning assembly is controlled to spray cleaning liquid from the center of the silicon wafer polishing pad to the edge of the silicon wafer polishing pad or from the edge of the silicon wafer polishing pad to the center of the silicon wafer polishing pad, wherein the spray path of the cleaning liquid is the projection of the transmission path of the second positioning signal on the silicon wafer polishing pad.

[0052] After controlling the polishing pad cleaning assembly to spray cleaning fluid onto the radius of the silicon wafer polishing pad based on the received result, the method further includes:

[0053] The steps include controlling the silicon wafer polishing pad to rotate by a second preset angle, returning to controlling the second positioning component to transmit the second positioning signal to the center of the silicon wafer polishing pad, and receiving the result of receiving the second positioning signal.

[0054] In some embodiments, after the method controls the first signal transmitter to transmit the first positioning signal to the vehicle positioning area, the method further includes:

[0055] Control the swing arm to drive the first signal transmitter to swing at a third preset angle, or control the swing arm to drive the first signal receiver to swing at a third preset angle, and return to the step of controlling the first signal transmitter to transmit the first positioning signal to the vehicle positioning area, until the first signal transmitter transmits N first positioning signals to the vehicle positioning area, where N is an integer greater than 1.

[0056] The embodiments of the present invention have the following beneficial effects:

[0057] The silicon wafer polishing apparatus provided in this embodiment of the invention is based on the principle that the positioning signal reflected by the silicon wafer carrier and the silicon wafer polishing pad has different signal intensities due to the different materials of the silicon wafer carrier and the silicon wafer polishing pad. After the silicon wafer carrier is placed on the silicon wafer polishing pad, a first positioning component transmits a first positioning signal to the carrier positioning area of ​​the silicon wafer polishing pad. The reflection intensity of the first positioning signal determines whether the first positioning signal is reflected by the silicon wafer carrier or the silicon wafer polishing pad. If it is reflected by the silicon wafer carrier, it can be determined that the placement position of the silicon wafer carrier on the silicon wafer polishing pad is correct. If it is reflected by the silicon wafer polishing pad, it can be determined that the placement position of the silicon wafer carrier on the silicon wafer polishing pad is incorrect or the placement angle of the silicon wafer carrier on the silicon wafer polishing pad is incorrect. The position of the silicon wafer carrier is then determined based on the reflection result of the first positioning signal. When correctly positioned, the silicon wafer is placed into the wafer receiving hole and subsequent polishing processes are performed without affecting the quality of the subsequent silicon wafer polishing. Furthermore, based on the difference in signal strength after the positioning signal is transmitted through the wafer carrier and air, a second positioning signal is emitted towards the center of the silicon wafer polishing pad via a second positioning component. The received strength of the second positioning signal determines whether it has been transmitted through the wafer carrier. If the received strength indicates that the second positioning signal has not been transmitted through the wafer carrier, the polishing pad cleaning component sprays cleaning fluid onto the radius of the silicon wafer polishing pad covered by the transmission path of the second positioning signal. This achieves cleaning of the silicon wafer polishing pad without the cleaning fluid contacting the wafer carrier, ensuring the cleaning effect of the cleaning fluid on the silicon wafer polishing pad and not affecting the quality of the subsequent silicon wafer polishing. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of the structure of the silicon wafer polishing apparatus provided in an embodiment of the present invention;

[0059] Figure 2 This is a schematic diagram illustrating the transmission path of the first positioning signal provided in an embodiment of the present invention;

[0060] Figure 3This is a flowchart illustrating the silicon wafer polishing method provided in an embodiment of the present invention.

[0061] Figure label:

[0062] 1: Silicon wafer polishing pad; 2: Silicon wafer carrier; 21: Silicon wafer receiving hole; 3: First positioning component; 31: First signal transmitter; 32: First signal receiver; 33: Swing arm; 4: Second positioning component; 5: Second signal receiver; 301-304: Steps. Detailed Implementation

[0063] To make the technical problems, technical solutions and advantages of the embodiments of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0064] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0065] To address the problems of poor silicon wafer polishing quality and poor polishing pad cleaning effect caused by the misalignment of the wafer carrier on the polishing pad, this invention provides a silicon wafer polishing apparatus and a silicon wafer polishing method.

[0066] like Figure 1 As shown, an embodiment of the present invention provides a silicon wafer polishing apparatus, comprising:

[0067] A circular silicon wafer polishing pad 1 is formed, and at least one circular silicon wafer carrier 2 is provided on the outer periphery of the silicon wafer polishing pad 1. Specifically, the position and number of silicon wafer carriers 2 placed on the silicon wafer polishing pad 1 can be set according to the size of the silicon wafer polishing pad 1 and the size of the silicon wafer carrier 2. Preferably, the silicon wafer carrier 2 is tangent to the silicon wafer polishing pad 1.

[0068] In this embodiment, the silicon wafer carrier 2 can also be referred to as a wafer carrier.

[0069] At least one silicon wafer receiving hole 21 is provided on the outer periphery of the silicon wafer carrier 2. The silicon wafer receiving hole 21 is used to place the silicon wafer. Specifically, the number and position of the silicon wafer receiving holes 21 on the silicon wafer carrier 2 can be set according to the size of the silicon wafer carrier 2 and the size of the silicon wafer receiving hole 21. Preferably, the silicon wafer receiving hole 21 is as close as possible to the edge of the silicon wafer carrier 2.

[0070] A first positioning component 3 is disposed on one side of the silicon wafer polishing pad 1. The first positioning component 3 is used to transmit a first positioning signal to the carrier positioning area of ​​the silicon wafer polishing pad 1. The carrier positioning area is the area on the silicon wafer polishing pad 1 where the part of the silicon wafer carrier 2 without the silicon wafer receiving hole 21 is not opened when the silicon wafer carrier 2 is correctly positioned. The first positioning signal is used to detect whether the position of the silicon wafer carrier 2 on the silicon wafer polishing pad 1 is correct.

[0071] Specifically, the carrier positioning area is pre-marked. During calibration, the silicon wafer carrier 2 is first correctly placed on the silicon wafer polishing pad 1. The area on the silicon wafer polishing pad 1 where the silicon wafer receiving hole 21 is not opened is marked as the carrier positioning area. Optionally, the carrier positioning area is set to a preset shape, such as a square area, a rectangular area, or a rhombus area. Figure 1 As shown, the carrier positioning area is a rhombus-shaped area. The carrier positioning area with the preset shape is selected and set within the coverage area of ​​the silicon wafer polishing pad 1 of the part of the silicon wafer carrier 2 where the silicon wafer receiving hole 21 is not opened. Preferably, when at least two silicon wafer receiving holes 21 are opened along the outer periphery of the silicon wafer carrier 2, when setting the carrier positioning area with the preset shape, it is ensured that the part of the carrier positioning area with the preset shape on the silicon wafer carrier 2 is located in the middle of two adjacent silicon wafer receiving holes 21, and is spaced at a preset distance from the edge of the silicon wafer carrier 2. That is, when the silicon wafer carrier 2 is correctly placed on the silicon wafer polishing pad 1, the carrier positioning area with the preset shape is located as close as possible to the middle of two adjacent silicon wafer receiving holes 21.

[0072] Because the silicon wafer carrier 2 and the silicon wafer polishing pad 1 are made of different materials—for example, the silicon wafer carrier 2 is made of diamond-like carbon (DLC) while the silicon wafer polishing pad 1 is made of rigid porous polyurethane foam—based on the principle that the signal strength of the positioning signal after reflection from the silicon wafer carrier 2 and the silicon wafer polishing pad 1 is different, the system controls the first positioning signal to be emitted towards the carrier positioning area. The reflection result of the first positioning signal is received, and it is determined whether the first positioning signal was received after reflection from the silicon wafer carrier 2 or after reflection from the silicon wafer polishing pad 1. If the reflection result determines that the first positioning signal was received after reflection from the silicon wafer carrier 2, then the silicon wafer carrier 2 is correctly positioned on the silicon wafer polishing pad 1, and subsequent silicon wafer placement and polishing can proceed. The photolithography process ensures the quality of subsequent silicon wafer polishing. If the reflection result confirms that the first positioning signal is received after being reflected by the silicon wafer polishing pad 1, it can be considered that the placement position of the entire silicon wafer carrier 2 on the silicon wafer polishing pad 1 is incorrect. Alternatively, if the first positioning signal is received after being reflected by the silicon wafer polishing pad 1 inside the silicon wafer receiving hole 21, it can be determined that the placement position of the silicon wafer carrier 2 is correct, but the placement angle of the silicon wafer carrier 2 is incorrect and needs to be adjusted. After adjustment, the above process is repeated until it is determined that the placement position of the silicon wafer carrier 2 on the silicon wafer polishing pad 1 is correct before proceeding with the subsequent silicon wafer placement and polishing process to ensure the quality of subsequent silicon wafer polishing.

[0073] The reflection result of the first positioning signal after passing through the silicon wafer carrier 2 is calibrated in advance, as is the reflection result of the first positioning signal after passing through the silicon wafer polishing pad 1.

[0074] When two or more silicon wafer carriers 2 are set on the silicon wafer polishing pad 1, the first positioning component 3 is controlled to rotate or the silicon wafer polishing pad 1 is controlled to rotate (the silicon wafer carrier 2 remains stationary). The above process is repeated until it is determined that the placement position of each silicon wafer carrier 2 is correct. Then, the subsequent silicon wafer placement and polishing process is carried out to ensure the quality of subsequent silicon wafer polishing.

[0075] The silicon wafer polishing apparatus further includes a polishing pad cleaning assembly disposed on one side of the silicon wafer polishing pad 1. The polishing pad cleaning assembly is used to spray cleaning liquid from the center of the silicon wafer polishing pad 1 to the edge of the silicon wafer polishing pad 1 or from the edge of the silicon wafer polishing pad 1 to the center of the silicon wafer polishing pad 1. That is, the spray path of the cleaning liquid is the radius on the polishing pad. The cleaning liquid is used to clean the silicates generated during the polishing process of the silicon wafer in order to carry out subsequent silicon wafer polishing.

[0076] The silicon wafer polishing apparatus further includes a second positioning component 4 located at the same height as the silicon wafer carrier 2 on the silicon wafer polishing pad 1 and disposed on one side of the silicon wafer polishing pad 1. The second positioning component 4 is used to transmit a second positioning signal to the center of the silicon wafer polishing pad 1, that is, the transmission path of the second positioning signal on the silicon wafer polishing pad 1 covers a radius of the silicon wafer polishing pad 1. The second positioning signal is used to detect whether the transmission path of the signal (i.e. the second positioning signal) passes through the silicon wafer carrier.

[0077] Specifically, based on the different signal strengths of the positioning signal after transmission through the silicon wafer carrier 2 and air, the second positioning component 4 transmits a second positioning signal to the center of the silicon wafer polishing pad 1. According to the received strength of the second positioning signal, it can be determined whether the second positioning signal is received after transmission through the silicon wafer carrier 2 or after transmission through air (i.e., after contact with the silicon wafer carrier 2). If it is determined that the second positioning signal is received after transmission through air, it can be determined that the second positioning signal detects the radius on the silicon wafer polishing pad 1 that is not covered by the silicon wafer carrier 2. Then, the polishing pad cleaning component is controlled to spray cleaning liquid along the radius covered by the transmission path of the second positioning signal on the silicon wafer polishing pad 1. This ensures that the cleaning liquid is not sprayed onto the silicon wafer carrier 2, but is sprayed onto the silicon wafer polishing pad 1, so that the cleaning liquid can clean the silicates on the silicon wafer polishing pad 1 without contacting the silicon wafer carrier 2, thus ensuring the quality of subsequent silicon wafer polishing. If the received strength of the second positioning signal indicates that the signal is received after transmission through the silicon wafer carrier 2, it can be determined that the second positioning signal detects the radius on the silicon wafer polishing pad 1 covered by the silicon wafer carrier 2. Then, the silicon wafer polishing pad 1 is controlled to rotate (while the silicon wafer carrier 2 remains stationary) or the position of the silicon wafer carrier 2 on the silicon wafer polishing pad 1 is adjusted. The second positioning component is then controlled to emit the second positioning signal again until it is determined that the second positioning signal detects the radius on the silicon wafer polishing pad 1 not covered by the silicon wafer carrier 2. Finally, the polishing pad cleaning component is controlled to spray cleaning fluid along the radius covered by the transmission path of the second positioning signal on the silicon wafer polishing pad 1. This avoids incomplete cleaning due to abnormal positioning of the silicon wafer carrier 2, which could lead to polishing pad glazing and subsequent product defects.

[0078] When two or more silicon wafer carriers 2 are set on the silicon wafer polishing pad 1, based on the above process, the second positioning component can detect the radius between two adjacent silicon wafer carriers 2, control the polishing pad cleaning component to spray cleaning fluid towards the radius, then control the silicon wafer polishing pad 1 to rotate (the silicon wafer carrier 2 remains stationary), and repeat the above process until the polishing pad cleaning component is controlled to spray cleaning fluid towards the radius between any two adjacent silicon wafer carriers 2.

[0079] The signal strength of the second positioning signal after transmission through the silicon wafer carrier 2 is pre-calibrated, and the signal strength of the second positioning signal after transmission through the air is also pre-calibrated.

[0080] In some embodiments, to ensure the number of silicon wafer carriers 2 placed on the silicon wafer polishing pad 1, the diameter of the silicon wafer carrier 2 is smaller than the radius of the silicon wafer polishing pad 1. Furthermore, setting the diameter of the silicon wafer carrier 2 to be smaller than the radius of the silicon wafer polishing pad 1 also ensures that the center of the silicon wafer polishing pad 1 is not covered by the silicon wafer carrier 2. This allows the radius of the silicon wafer polishing pad 1 covered by the silicon wafer carrier 2 to be detected by a second positioning signal. For example, such as... Figure 1 As shown, five silicon wafer carriers 2 are placed on the silicon wafer polishing pad 1.

[0081] To ensure the number of silicon wafers placed on the silicon wafer carrier 2, the diameter of the silicon wafer receiving hole 21 is smaller than the radius of the silicon wafer carrier 2. For example, as shown in the figure... Figure 1 As shown, the silicon wafer carrier 2 has three silicon wafer receiving holes 21.

[0082] The silicon wafer polishing pad 1 is used to rotate around the center of the silicon wafer polishing pad 1. It can also be understood that the silicon wafer polishing pad 1 is used to drive the silicon wafer carrier 2 to perform planetary motion around the center. Since the silicon wafer polishing pad 1 can drive the silicon wafer carrier 2 to rotate around the center of the silicon wafer polishing pad 1, the relative position between the silicon wafer carrier 2 and the polishing pad cleaning assembly can be adjusted. The radius between any two adjacent silicon wafer carriers 2 can be detected by the second positioning signal mentioned above, and then the polishing pad cleaning assembly is controlled to spray cleaning liquid towards the radius.

[0083] In some embodiments, the first positioning component 3 includes a first signal transmitter 31 and a first signal receiver 32 disposed on one side of the silicon wafer polishing pad 1;

[0084] The first signal transmitter 31 is used to transmit the first positioning signal to the positioning area of ​​the carrier, and the first signal receiver 32 is used to receive the first positioning signal and obtain the reflection result (also known as the reflection intensity) of the first positioning signal. Based on the reflection result, it is determined whether the first positioning signal is received after being reflected by the silicon wafer carrier 2 or after being reflected by the silicon wafer polishing pad 1. That is, the reflection result is used to indicate whether the position of the silicon wafer carrier 2 on the silicon wafer polishing pad 1 is correct.

[0085] Furthermore, such as Figure 1 As shown, the first signal transmitter 31 and the first signal receiver 32 are connected by a swing arm 33; the swing arm 33 is used to drive the first signal transmitter 31 to swing, or the swing arm 33 is used to drive the first signal receiver 32 to swing.

[0086] In this embodiment, the first signal transmitter 31 and the first signal receiver 32 are connected by a swing arm 33, which swings the first signal transmitter 31 or the first signal receiver 32 at different angles. This allows the first signal transmitter 31 to sequentially transmit multiple first positioning signals to different positions within the carrier positioning area from different positions (which are then received by the first signal receiver 32 after reflection at different positions). Alternatively, the first signal receiver 32 can receive multiple first positioning signals sequentially reflected from different positions within the carrier positioning area from different positions. Based on the reflection results of these multiple first positioning signals, the position of the silicon wafer carrier 2 on the silicon wafer polishing pad 1 is determined to be correct, resulting in more accurate detection. Specifically, the number of the first positioning signals can be set according to requirements or the size of the carrier positioning area. The transmission path of the first positioning signals is as follows: Figure 2 As shown, for each carrier positioning area, the position of the silicon wafer carrier 2 on the silicon wafer polishing pad 1 is determined based on the reflection results of the three first positioning signals.

[0087] Optionally, the first signal transmitter 31 includes at least one of the following:

[0088] Laser signal transmitter;

[0089] Infrared signal transmitter;

[0090] Ultrasonic signal transmitter;

[0091] The first signal receiver 32 includes at least one of the following:

[0092] Laser signal receiver;

[0093] Infrared signal receiver;

[0094] Ultrasonic signal receiver.

[0095] It should be noted that the types of the first signal transmitter 31 and the first signal receiver 32 need to correspond. The specific types of the first signal transmitter 31 and the first signal receiver 32 can be set according to requirements, and are not limited in this embodiment.

[0096] In some embodiments, the polishing pad cleaning assembly includes a mounting bracket, a telescopic tube, and a cleaning nozzle;

[0097] The first end of the telescopic tube is fixedly connected to the fixed bracket, and the second end of the telescopic tube is connected to the cleaning nozzle. The cleaning liquid can flow to the cleaning nozzle through the telescopic tube. Preferably, in order to ensure the cleaning effect, the cleaning nozzle is a high-pressure nozzle. The cleaning liquid sprayed by the high-pressure nozzle is a high-pressure water jet, which makes the cleaning of the silicon wafer polishing pad 1 more thorough.

[0098] The telescopic tube is used to drive the cleaning nozzle to extend and retract along the radius of the silicon wafer polishing pad 1. The cleaning nozzle is used to spray cleaning liquid onto the radius of the silicon wafer polishing pad 1. Preferably, during cleaning, the telescopic tube first extends to the center of the silicon wafer polishing pad 1 (i.e., the center of the silicon wafer polishing pad 1 is the cleaning origin). Then, the telescopic tube is controlled to retract back to the fixed bracket. This retraction is along the radius of the silicon wafer polishing pad 1. During the retraction process, the cleaning nozzle sprays cleaning liquid onto this radius to clean the silicon wafer polishing pad 1.

[0099] The second positioning component 4 is fixedly connected to the fixed bracket, that is, the second positioning component 4 is located on the extension line of the radius of the silicon wafer polishing pad 1.

[0100] In some embodiments, the second positioning component 4 includes a second signal transmitter, and the silicon wafer polishing device further includes a second signal receiver 5. The second signal receiver 5 is disposed at the center of the silicon wafer polishing pad. The second signal transmitter is used to transmit the second positioning signal to the center of the silicon wafer polishing pad 1. The second signal receiver 5 is used to receive the second positioning signal and obtain the reception result (also known as the reception strength) of the second positioning signal. The reception result is used to indicate whether the transmission path of the signal (i.e., the second positioning signal) passes through the silicon wafer carrier. That is, based on the reception result, it is determined whether the second positioning signal is received after being transmitted through the silicon wafer carrier 2 or after being transmitted through the air, thereby determining whether the position of the silicon wafer carrier 2 relative to the polishing pad cleaning component is correct, i.e., whether the polishing pad cleaning component is used to clean the silicon wafer polishing pad 1.

[0101] Optionally, the second signal transmitter includes at least one of the following:

[0102] Laser signal transmitter;

[0103] Infrared signal transmitter;

[0104] Ultrasonic signal transmitter;

[0105] The second signal receiver includes at least one of the following:

[0106] Laser signal receiver;

[0107] Infrared signal receiver;

[0108] Ultrasonic signal receiver.

[0109] It should be noted that the types of the second signal transmitter and the second signal receiver 5 need to correspond. The specific types of the first signal transmitter and the second signal receiver 5 can be set according to requirements, and are not limited in this embodiment.

[0110] like Figure 3As shown, embodiments of the present invention also provide a silicon wafer polishing method, applied to the silicon wafer polishing apparatus as described in any of the preceding claims, the method comprising:

[0111] Step 301: Control the first positioning component to transmit a first positioning signal to the positioning area of ​​the vehicle, and receive the reflection result of the first positioning signal.

[0112] In this step, after the origin of each point of the equipment is zeroed, the silicon wafer carrier is placed on the silicon wafer polishing pad, the first positioning component is started, the first positioning signal is emitted to the positioning area of ​​the carrier, and the reflection result of the first positioning signal is obtained.

[0113] Step 302: If the placement position of the silicon wafer carrier is determined to be correct based on the reflection results, the silicon wafer placement and silicon wafer polishing processes are performed.

[0114] Because the silicon wafer carrier and the silicon wafer polishing pad are made of different materials, the reflection result (or reflection intensity) of the first positioning signal after reflection by the silicon wafer carrier and the silicon wafer polishing pad is different. This can determine whether the placement position of the silicon wafer carrier is correct. If the placement position of each silicon wafer carrier is correct, the silicon wafer is placed in the silicon wafer receiving hole and the subsequent silicon wafer polishing process is performed to ensure that the silicon wafer is placed in the correct position and to ensure the quality of the subsequent silicon wafer polishing process.

[0115] Step 303: After the silicon wafer polishing process is completed, control the second positioning component to send the second positioning signal to the center of the silicon wafer polishing pad, and receive the reception result of the second positioning signal.

[0116] Since the reception results (or reception strength) of the second positioning signal after transmission through the silicon wafer carrier and air are different, it can be determined whether the second positioning signal detects the radius of the silicon wafer polishing pad that is not covered by the silicon wafer carrier based on the reception results.

[0117] Step 304: Based on the received result, control the polishing pad cleaning assembly to spray cleaning fluid onto the radius of the silicon wafer polishing pad.

[0118] In this step, if the radius of the silicon wafer polishing pad that is not covered by the silicon wafer carrier is detected according to the second positioning signal, the polishing pad cleaning component is controlled to spray cleaning liquid onto the radius to clean the silicon wafer polishing pad, so as to ensure the quality of subsequent silicon wafer polishing.

[0119] In some embodiments, controlling the first positioning component to transmit a first positioning signal to the vehicle positioning area includes:

[0120] When two or more silicon wafer carriers are set on a silicon wafer polishing pad, the first signal transmitter is controlled to transmit the first positioning signal to the positioning area of ​​the carrier.

[0121] The silicon wafer polishing pad is controlled to rotate by a first preset angle, that is, the silicon wafer polishing pad drives the silicon wafer carrier on it to rotate by a first preset angle. It should be noted that the first preset angle is determined according to the size of the silicon wafer carrier and the size of the silicon wafer polishing pad.

[0122] The step of returning to the first signal transmitter transmitting the first positioning signal to the carrier positioning area is to control the first signal transmitter to transmit the first positioning signal to the carrier positioning area corresponding to another silicon wafer carrier until the first signal transmitter transmits at least two first positioning signals to the carrier positioning area, that is, to control the first positioning component to transmit the first positioning signal to the carrier positioning area corresponding to each silicon wafer carrier.

[0123] The reflection result of receiving the first positioning signal includes:

[0124] The first signal receiver sequentially receives the reflection result of each of the at least two first positioning signals. Specifically, after the first signal transmitter transmits the first positioning signal to the carrier positioning area corresponding to each silicon wafer carrier, the first signal receiver is controlled to receive the reflection result of the first signal.

[0125] The process of placing and polishing the silicon wafer after determining that the placement position of the silicon wafer carrier is correct based on the reflection result includes:

[0126] If the reflection result of each of the first positioning signals indicates that the first positioning signal is received by the first signal receiver after being reflected by the positioning area of ​​the carrier, it is determined that the silicon wafer carrier is correctly positioned on the silicon wafer polishing pad, and the silicon wafer is placed in the silicon wafer receiving hole for silicon wafer polishing process.

[0127] The correct placement of the silicon wafer carrier on the silicon wafer polishing pad includes that the placement position and angle of each silicon wafer carrier on the silicon wafer polishing pad are correct.

[0128] In some embodiments, controlling the second positioning component to transmit the second positioning signal toward the center of the silicon wafer polishing pad includes:

[0129] Control the second signal transmitter to transmit the second positioning signal toward the center of the silicon wafer polishing pad;

[0130] The reception result of receiving the second positioning signal includes:

[0131] The reception result of the second positioning signal is received by the second signal receiver;

[0132] The step of controlling the polishing pad cleaning assembly to spray cleaning fluid onto the radius of the silicon wafer polishing pad based on the received result includes:

[0133] When the receiving result indicates that the second positioning signal was received by the second signal receiver after being transmitted through the silicon wafer carrier (i.e., the second positioning signal was received by the second signal receiver after being transmitted through the air), that is, the projection area of ​​the transmission path of the second positioning signal on the silicon wafer polishing pad is the radius of the silicon wafer polishing pad that is not covered by the silicon wafer carrier, the polishing pad cleaning assembly is controlled to spray cleaning liquid from the center of the silicon wafer polishing pad to the edge of the silicon wafer polishing pad or from the edge of the silicon wafer polishing pad to the center of the silicon wafer polishing pad, wherein the spray path of the cleaning liquid is the projection of the transmission path of the second positioning signal on the silicon wafer polishing pad;

[0134] After controlling the polishing pad cleaning assembly to spray cleaning fluid onto the radius of the silicon wafer polishing pad based on the received result, the method further includes:

[0135] The steps include controlling the silicon wafer polishing pad to rotate by a second preset angle, returning to control the second positioning component to transmit the second positioning signal to the center of the silicon wafer polishing pad, and receiving the result of receiving the second positioning signal, wherein the second preset angle is determined based on the size of the silicon wafer carrier and the size of the silicon wafer polishing pad.

[0136] In this embodiment, when multiple silicon wafer carriers are arranged on the silicon wafer polishing pad, the second signal transmitter is first controlled to transmit a second positioning signal between two adjacent silicon wafer carriers. Based on the reception result of the second positioning signal, it is determined whether the second positioning signal was received after being transmitted through the area between the two silicon wafer carriers. If the second positioning signal was received after being transmitted through the area between the two silicon wafer carriers, the polishing pad cleaning assembly is controlled to spray cleaning liquid into the radius. Then, the silicon wafer polishing pad is controlled to rotate a second preset angle, and the second signal transmitter is controlled again to transmit a second positioning signal between another pair of adjacent silicon wafer carriers. It is determined whether the second positioning signal was received after being transmitted through the area between the other pair of adjacent silicon wafer carriers, until the polishing pad cleaning assembly sprays cleaning liquid into the radius of the area between each pair of adjacent silicon wafer carriers.

[0137] Furthermore, after controlling the first signal transmitter to transmit the first positioning signal to the vehicle positioning area, the method further includes:

[0138] The control arm drives the first signal transmitter to swing at a third preset angle, or the control arm drives the first signal receiver to swing at a third preset angle, and returns to the step of controlling the first signal transmitter to transmit the first positioning signal to the vehicle positioning area, until the first signal transmitter transmits N first positioning signals to the vehicle positioning area, where N is an integer greater than 1. The specific value of N can be set according to the requirements. Preferably, N is 3. The specific value of the second preset angle can be set according to the requirements, and is not limited in this embodiment.

[0139] It should be noted that by connecting the first signal transmitter and the first signal receiver with a swing arm and swinging the first signal transmitter or the first signal receiver at different angles, it is possible to achieve that the first signal transmitter transmits N first positioning signals sequentially to different positions within the positioning area of ​​the carrier at different positions (and receive them after being reflected at different positions), or the first signal receiver receives N first positioning signals sequentially reflected from different positions within the positioning area of ​​the carrier at different positions. Based on the reflection results of these N first positioning signals, it is possible to more accurately determine whether the placement position of the silicon wafer carrier on the silicon wafer polishing pad is correct.

[0140] It should be noted that the silicon wafer polishing method provided in the embodiments of the present invention is applied to the silicon wafer polishing apparatus as described in any of the above-mentioned embodiments. Therefore, all embodiments of the silicon wafer polishing apparatus described above are applicable to this method and can achieve the same or similar technical effects.

[0141] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A silicon wafer polishing apparatus, characterized by comprising: The application relates to a silicon wafer polishing pad, which comprises the following parts: a silicon wafer polishing pad in a circular shape, at least one silicon wafer carrier in a circular shape arranged along the outer periphery of the silicon wafer polishing pad; at least one silicon wafer accommodating hole arranged along the outer periphery of the silicon wafer carrier, which is used for placing a silicon wafer; a first positioning component arranged on one side of the silicon wafer polishing pad, which is used for emitting a first positioning signal to a carrier positioning area of the silicon wafer polishing pad, wherein the carrier positioning area is a covering area of the silicon wafer carrier on the silicon wafer polishing pad, which is not provided with the silicon wafer accommodating hole when the silicon wafer carrier is correctly placed, and the first positioning signal is used for detecting whether the silicon wafer carrier is correctly placed on the silicon wafer polishing pad; a polishing pad cleaning component arranged on one side of the silicon wafer polishing pad, which is used for spraying cleaning liquid from the center of the silicon wafer polishing pad to the edge of the silicon wafer polishing pad or from the edge of the silicon wafer polishing pad to the center of the silicon wafer polishing pad; a second positioning component arranged on one side of the silicon wafer polishing pad and at the same height as the silicon wafer carrier on the silicon wafer polishing pad, which is used for emitting a second positioning signal to the center of the silicon wafer polishing pad, and the second positioning signal is used for detecting whether the transmission path of the signal passes through the silicon wafer carrier.

2. The silicon wafer polishing apparatus of claim 1, wherein The diameter of the silicon wafer carrier is smaller than the radius of the silicon wafer polishing pad; The diameter of the silicon wafer accommodating hole is smaller than the radius of the silicon wafer carrier; The silicon wafer polishing pad is used for rotating around the center of the silicon wafer polishing pad.

3. The apparatus of claim 1 wherein, The first positioning component comprises a first signal transmitter and a first signal receiver arranged on one side of the silicon wafer polishing pad; The first signal transmitter is used for emitting the first positioning signal to the carrier positioning area, and the first signal receiver is used for receiving the first positioning signal and obtaining the reflection result of the first positioning signal, which is used for indicating whether the silicon wafer carrier is correctly placed on the silicon wafer polishing pad; The second positioning component comprises a second signal transmitter, and the silicon wafer polishing device further comprises a second signal receiver; The second signal receiver is arranged on the center of the silicon wafer polishing pad; The second signal transmitter is used for emitting the second positioning signal to the center of the silicon wafer polishing pad, and the second signal receiver is used for receiving the second positioning signal and obtaining the receiving result of the second positioning signal, which is used for indicating whether the transmission path of the signal passes through the silicon wafer carrier.

4. The silicon wafer polishing apparatus of claim 3, wherein The first signal transmitter and the first signal receiver are connected through a swing arm; The swing arm is used for swinging the first signal transmitter, or the swing arm is used for swinging the first signal receiver.

5. The apparatus of claim 3 wherein: The first signal transmitter and the second signal transmitter comprise at least one of the following: a laser signal transmitter; an infrared signal transmitter; an ultrasonic signal transmitter; The first signal receiver and the second signal receiver comprise at least one of the following: a laser signal receiver; an infrared signal receiver; an ultrasonic signal receiver.

6. The silicon wafer polishing apparatus of claim 1, wherein The polishing pad cleaning component comprises a fixed support, an extension tube and a cleaning nozzle. The first end of the telescopic pipe is fixedly connected with the fixed support, and the second end of the telescopic pipe is connected with the cleaning nozzle. The telescopic pipe is used to drive the cleaning nozzle to move telescopically on the radius of the silicon wafer polishing pad, and the cleaning nozzle is used to spray cleaning liquid on the radius of the silicon wafer polishing pad. The second positioning assembly is fixedly connected with the fixed support.

7. A method of polishing a silicon wafer, characterized by, The method is applied to the silicon wafer polishing device as claimed in any one of claims 1 to 6, and the method comprises: controlling the first positioning assembly to emit a first positioning signal to the carrier positioning area and receiving a reflection result of the first positioning signal; in the case where it is determined according to the reflection result that the placement position of the silicon wafer carrier is correct, carrying out silicon wafer placement and silicon wafer polishing process; after the silicon wafer polishing process is completed, controlling the second positioning assembly to emit the second positioning signal to the center of the silicon wafer polishing pad and receiving a receiving result of the second positioning signal; controlling the polishing pad cleaning assembly to spray cleaning liquid on the radius of the silicon wafer polishing pad according to the receiving result.

8. The method of claim 7, wherein, The method is applied to the silicon wafer polishing device as claimed in claim 3, and the controlling the first positioning assembly to emit a first positioning signal to the carrier positioning area comprises: controlling a first signal emitter to emit the first positioning signal to the carrier positioning area; controlling the silicon wafer polishing pad to rotate by a first preset angle and returning to the step of controlling the first signal emitter to emit the first positioning signal to the carrier positioning area until controlling the first signal emitter to emit at least two first positioning signals to the carrier positioning area; the receiving a reflection result of the first positioning signal comprises: receiving, by a first signal receiver, a reflection result of each of the at least two first positioning signals in turn; the in the case where it is determined according to the reflection result that the placement position of the silicon wafer carrier is correct, carrying out silicon wafer placement and silicon wafer polishing process comprises: in the case where the reflection result of each of the first positioning signals indicates that the first positioning signal is received by the first signal receiver after being reflected via the carrier positioning area, it is determined that the placement position of the silicon wafer carrier on the silicon wafer polishing pad is correct, a silicon wafer is placed in a silicon wafer containing hole, and a silicon wafer polishing process is carried out; the controlling the second positioning assembly to emit the second positioning signal to the center of the silicon wafer polishing pad comprises: controlling a second signal emitter to emit the second positioning signal to the center of the silicon wafer polishing pad; the receiving a receiving result of the second positioning signal comprises: receiving, by a second signal receiver, a receiving result of the second positioning signal; the controlling the polishing pad cleaning assembly to spray cleaning liquid on the radius of the silicon wafer polishing pad according to the receiving result comprises: in a case that the receiving result indicates that the second positioning signal is not transmitted by the silicon wafer carrier, controlling the polishing pad cleaning assembly to spray cleaning liquid from the center of the silicon wafer polishing pad to the edge of the silicon wafer polishing pad or from the edge of the silicon wafer polishing pad to the center of the silicon wafer polishing pad, wherein a spraying path of the cleaning liquid is a projection of a transmission path of the second positioning signal on the silicon wafer polishing pad; after the step of controlling the polishing pad cleaning assembly to spray cleaning liquid to the radius of the silicon wafer polishing pad according to the receiving result, the method further comprises: controlling the silicon wafer polishing pad to rotate by a second preset angle, and returning to the step of controlling the second positioning assembly to emit the second positioning signal to the center of the silicon wafer polishing pad.

9. The method of claim 8, wherein, The method is applied to the silicon wafer polishing device as claimed in claim 4, and after the step of controlling the first signal emitter to emit the first positioning signal to the carrier positioning area, the method further comprises: controlling the swing arm to swing the first signal emitter by a third preset angle, or controlling the swing arm to swing the first signal receiver by a third preset angle, and returning to the step of controlling the first signal emitter to emit the first positioning signal to the carrier positioning area until N first positioning signals are emitted by the first signal emitter to the carrier positioning area, N being an integer greater than 1.

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