Detection device and detection method for CMP cleaning and drying module

Abstract

Disclosed in the present invention are a detection device and detection method for a CMP cleaning and drying module. The detection device comprises a light generation unit; a light receiving unit; a wafer clamping unit, used for clamping a wafer and driving same to rotate, located between the light generation unit and the light receiving unit, and partially located in a light beam or a light curtain, the wafer clamping unit at least having a closed state and an open state; and a data processing unit, used for acquiring projection information generated on the light receiving unit after the light beam or the light curtain is shielded by the wafer and / or the wafer clamping unit, and on the basis of the projection information, determining whether the wafer clamping unit clamps the wafer or not and / or determining whether the wafer clamped by the wafer clamping unit is horizontal or not and / or state information of the wafer clamping unit. Also disclosed in the present invention is a wafer detection method for a CMP cleaning and drying module. The present invention combines wafer existence detection, detecting whether a wafer is horizontal, and wafer clamping unit state detection, and thus improves the detection efficiency of a cleaning and drying device on whether the wafer is correctly placed or not.

Description

A detection device and detection method for CMP cleaning and drying module Technical Field

[0001] The present invention belongs to the technical field of semiconductor processing equipment, and in particular relates to a detection device and a detection method for a CMP cleaning and drying module. Background Art

[0002] Chemical Mechanical Planarization (CMP) equipment typically includes a semiconductor equipment front-end module (EFEM), a cleaning unit, and a polishing unit. Existing CMP cleaning units include cleaning and drying devices, such as a spin-rinse dryer (SRD) that dries wafers or a device that uses IPA to clean and dry wafers. Regardless of the cleaning and drying method used, the wafer must be placed parallel to the bottom surface of the clamping jaws of the device that cleans and dries the wafer. If the wafer is not successfully placed parallel to the bottom surface of the clamping jaws as required, the clamping jaws may not be able to secure the wafer. A poorly secured wafer will fall out of the workstation during the drying process, damaging the wafer and the device. Therefore, before the cleaning and drying module operates, it is necessary to check whether the wafer has been successfully placed on the plane required by the cleaning and drying module and is placed horizontally.

[0003] The current technology uses two sets of transmissive laser sensors to detect wafer level and wafer presence. This solution results in long debugging time, high cost, complex mechanical structure, long detection feedback time, and unsightly complex devices. In addition, when the tilted wafer is parallel to the laser sensor beam for detection, the presence of the wafer cannot be effectively detected, which will cause abnormal judgment by the host computer under working conditions.

[0004] Summary of the Invention

[0005] In order to overcome the shortcomings of the existing technology, the present invention provides a detection device and detection method for a CMP cleaning and drying module, which can realize wafer presence detection, wafer level detection and wafer clamping unit status detection, thereby improving the detection efficiency of whether the wafer is correctly placed.

[0006] The technical solution adopted by the present invention to solve the technical problem is: a detection device for a CMP cleaning and drying module, comprising:

[0007] A light generating unit, for generating a light beam or a light curtain;

[0008] A light receiving unit, configured to receive the light beam or light curtain generated by the light generating unit and convert the light signal into an electrical signal;

[0009] A wafer clamping unit, for clamping the wafer and driving the wafer to rotate, is located between the light generating unit and the light receiving unit, and is at least partially within the light beam or light curtain generated by the light generating unit. The wafer clamping unit has at least a closed state and an open state;

[0010] A data processing unit is used to obtain projection information generated on the light receiving unit after the light beam or light curtain generated by the light generating unit is blocked by the wafer and / or the wafer clamping unit, and to determine whether the wafer clamping unit is clamping a wafer and / or whether the wafer clamped by the wafer clamping unit is horizontal and / or the status information of the wafer clamping unit based on the projection information.

[0011] Furthermore, the wafer clamping unit includes a wafer fixing clamping base, a base driving motor for driving the wafer fixing clamping base to rotate around its own axis, and at least three wafer fixing clamps provided on the wafer fixing clamping base.

[0012] Furthermore, the data processing unit can obtain the motor angle value of the base drive motor in real time.

[0013] Furthermore, the projection information acquired by the data processing unit is a width value or an area value of the light beam generated by the light generating unit or the blocked area of ​​the light curtain.

[0014] Furthermore, a signal processing amplifier is provided between the data processing unit and the light receiving unit, which is used to convert the electrical signal from the light receiving unit to a power level that meets the conversion processing requirements.

[0015] The present invention also discloses a wafer detection method for a CMP cleaning and drying module, comprising the following steps:

[0016] The light generating unit and the light receiving unit are placed parallel to or at a certain angle relative to the plane where the wafer is located, the wafer clamping unit is located between the light generating unit and the light receiving unit, and at least part of the wafer and the wafer clamping unit are located within the light beam or light curtain generated by the light generating unit;

[0017] When the wafer is placed horizontally, the projection information of the light beam generated by the light generating unit or the light curtain generated by the light receiving unit is obtained;

[0018] When the wafer clamping unit is in an open state, obtaining projection information of the light beam generated by the light generating unit or the light curtain generated on the light receiving unit;

[0019] When the wafer is in a minimum tilt state that does not meet the requirements, the projection information of the light beam generated by the light generating unit or the light curtain generated by the light receiving unit is obtained;

[0020] When the wafer clamping unit is in a closed state, obtaining projection information of the light beam generated by the light generating unit or the light curtain generated on the light receiving unit;

[0021] The data processing unit determines whether the wafer clamping unit holds a wafer and / or whether the wafer clamped by the wafer clamping unit is horizontal and / or the status information of the wafer clamping unit based on the acquired projection information 1, projection information 2, projection information 3 and projection information 4.

[0022] Furthermore, the minimum tilt state of the wafer that does not meet the requirements is that under clean and dry conditions, the wafer clamping unit drives the tilted wafer to rotate, and the centrifugal force acting on the wafer just exceeds the restraining force, causing it to leave the limited position. At this time, the tilt state of the wafer is the minimum tilt state that does not meet the requirements.

[0023] Further, the following steps are included:

[0024] The light generating unit and the light receiving unit are placed parallel to or at a certain angle relative to the plane where the wafer is located, the wafer clamping unit is located between the light generating unit and the light receiving unit, and the wafer and the wafer fixing claw part of the wafer clamping unit are located within the light beam or light curtain generated by the light generating unit;

[0025] When the wafer is placed horizontally and the wafer clamping unit is in an open state, the wafer clamping unit rotates according to the set reference value to obtain the rotation interval. The set reference value to obtain the rotation interval ensures that all wafer fixing claws pass through the light beam or light curtain emitted by the light generating unit, and obtains the projection information 1 and projection information 2 obtained by the light receiving unit within the rotation interval. The time or motor rotation angle is used as the horizontal axis and the projection information is used as the vertical axis to draw a curve ρ0 as a reference curve;

[0026] When the wafer is in a minimum tilt state that does not meet the requirements and the wafer clamping unit is in an open state, the reference value set by the wafer clamping unit is obtained by rotating the rotation interval. The set reference value obtains the rotation interval to ensure that all wafer fixing claws pass through the light beam or light curtain emitted by the light generating unit, and obtains the set reference value. The second and third projection information obtained by the light receiving unit within the rotation interval are obtained, and the time or motor rotation angle is used as the horizontal axis and the projection information is used as the vertical axis to draw a curve ρ1;

[0027] When the wafer is placed horizontally and a single wafer fixing clamp of the wafer clamping unit is in a closed state, the wafer clamping unit rotates according to a set reference value to obtain a rotation interval. The set reference value to obtain the rotation interval ensures that all wafer fixing clamps pass through the light beam or light curtain emitted by the light source. The set reference value to obtain projection information 1 and projection information 4 obtained by the light receiving unit within the rotation interval are obtained, and a curve ρ2 is drawn with time or motor rotation angle as the horizontal axis and projection information as the vertical axis;

[0028] According to the curve ρ0, the set reference value acquisition rotation interval is divided into a wafer detection angle interval, a wafer fixed clamp detection angle interval, each wafer detection angle interval or each wafer fixed clamp detection angle interval interval angle;

[0029] According to the curve ρ0, the average value of the projection information 1 within the wafer detection angle range is obtained as d1. This reference value can be used as a reference value for the wafer thickness. Under working conditions, if the difference between the average value of several data sets selected from the wafer detection angle range within the set detection rotation range and d1 exceeds the set threshold, it means that the wafer does not exist. If the difference with d1 is within the set threshold range, it means that the wafer exists.

[0030] According to the curves ρ0 and ρ1, the wafer tilt judgment reference value p is determined w , record the set reference value to obtain the projection information within the rotation interval that is greater than the reference value p w The number of data is x w0 Under working conditions, record the wafer detection angle range within the set detection rotation range that is greater than the reference value p w The number of data is x w1 , if x w1 with x w0 If the difference between x and w1 with x w0 If the difference is within the set threshold, it indicates the wafer level;

[0031] According to the curves ρ0 and ρ2, the reference value p of the wafer fixing clamp is determined. c , record the set reference value to obtain the projection information within the rotation interval that is greater than the reference value p c The number of data is x c0 Under working conditions, record the detection angle range of the wafer fixed clamp within the detection rotation range that is greater than the reference value p c The number of data is x c1 , if x c1 with x c0 If the difference between x and x exceeds the set threshold, it means that one or more wafer clamps are closed. c1 with x c0 If the difference is within the threshold range, it means that the wafer fixing clamps are all in the open state.

[0032] Furthermore, the p w is 2 / 3 of the peak value of the ρ0 curve; c It is 49 / 50 of the peak value of the ρ0 curve.

[0033] Furthermore, the data processing unit calculates the tilt angle θ of the wafer relative to the light beam or the light curtain based on the acquired projection information 1 and the projection information of the wafer detection angle range under the working condition.

[0034] Furthermore, the wafer width is D, the wafer thickness is d, and at a certain moment within the rotation setting angle, the light beam or light curtain is blocked by a width of H1, then the wafer tilt angle at this time is:

[0035] Furthermore, the set reference value acquisition rotation interval is a rotation angle interval of the base drive motor, or a rotation time interval of the base drive motor.

[0036] The present invention provides a solution for detecting the presence or absence of a wafer and whether the wafer is level, which can more simply and conveniently detect the presence or absence of a wafer in a cleaning and drying module and whether the wafer is parallel, and can efficiently detect the presence or absence of a wafer in a CMP cleaning and drying module and whether the wafer is level, thereby improving the accuracy and efficiency of detecting the presence or absence of wafers and detecting the level of wafers in the cleaning and drying module, and reducing the probability of damage caused by wafers being thrown out due to not being placed levelly; the device can realize status detection of wafer clamps, and can effectively avoid tilting or breaking of wafers caused by abnormal jamming of the wafer clamps when a robot places or removes a wafer.

[0037] The beneficial effects of the present invention are as follows: 1) wafer presence detection, wafer level detection and wafer clamping unit status detection are combined through the light generating unit and the light receiving unit, and are used for independent detection or combined detection of any of the above three situations, thereby improving the detection efficiency of the cleaning and drying device for whether the wafer is correctly placed, and reducing the total time of the wafer cleaning and drying process; 2) by improving the detection method and structure of wafer presence detection and wafer level detection (using a light generating unit to generate a light beam or a light curtain, using a light receiving unit to receive light, and using a data processing unit to analyze and process signals), the number of parts of the entire detection system is effectively reduced, the debugging time and cost are reduced, and the mechanical structure is reduced. or multiple detection devices combined with detection to reduce the occurrence rate of failures caused by detection, thereby improving the simplicity and beauty of the device; 3) Since the presence or absence of the wafer and the horizontal state of the wafer are judged by the light signal received by the light receiving unit, the wafer detection and parallelism measurement device in the present invention is applicable regardless of whether the cleaning and drying module is designed to place the wafer vertically or horizontally; 4) Since the light generating unit and the light receiving unit can operate in real time, the data processing unit can process the light signal received by the light receiving unit in real time, thereby realizing real-time detection of the presence or absence of the wafer, the wafer level and the wafer clamping state under the complete working conditions of the CMP cleaning and drying module; 5) The specific tilt angle of the wafer can be calculated and used to participate in the judgment, effectively improving the efficiency of the process flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG1 is a top view of the present invention.

[0039] FIG2 is a front view of the present invention.

[0040] FIG3 is a schematic diagram of a signal of a light receiving unit when the wafer is in a horizontal state.

[0041] FIG4 is a schematic diagram of a signal of a light receiving unit when the wafer is in a tilted state.

[0042] FIG5 is a schematic diagram of a signal of a light receiving unit when the wafer fixing clamp is in an open state.

[0043] FIG6 is a schematic diagram of a signal of a light receiving unit when the wafer fixing clamp is in a closed state.

[0044] FIG7 is a schematic diagram of wafer tilt angle calculation.

[0045] FIG8 is a schematic diagram of the angle division of the detection interval.

[0046] FIG9 is a process flow chart of the wafer detection method of the present invention.

[0047] Among them, 1-wafer fixing clamp, 2-wafer, 3-wafer fixing clamp base, 4-base driving motor, 5-cleaning liquid transmission pipeline, 6-light generating unit, 7-light receiving unit, 8-signal processing amplifier, 9-data processing unit. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the solutions of the present invention, the following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0049] A detection device for a CMP cleaning and drying module includes a light generating unit 6 for generating a light beam or a light curtain, a light receiving unit 7 for receiving the light beam or light curtain generated by the light generating unit 6 and converting the light signal into an electrical signal, a wafer clamping unit for clamping a wafer 2 and driving the wafer 2 to rotate, and a data processing unit 9.

[0050] The light receiving unit 7 and the light generating unit 6 are arranged parallel to or at an angle relative to the plane of the wafer 2. The angle can be any angle. The wafer clamping unit is located between the light generating unit 6 and the light receiving unit 7, and the wafer clamping unit is at least partially within the light beam or light curtain generated by the light generating unit 6. The wafer clamping unit has at least a closed state and an open state.

[0051] Specifically, the light generating unit 6 and the light receiving unit 7 can be laser displacement sensors having a transmitting end and a receiving end. During the measurement process, the light beam or light curtain generated by the sensor transmitting end is received by the receiving end. When the wafer or the wafer clamping unit enters the light beam or light curtain, the light beam or light curtain is partially blocked by the wafer. The presence and horizontal state of the wafer are determined by the light signal received by the sensor receiving end. Of course, the light receiving unit 7 can also be a light receiving device that combines a photosensitive element and a signal processing amplifier, or an image recording device equipped with a CMOS sensor, or an image recording device equipped with a CCD sensor, or a photoelectric conversion device, without specific limitation.

[0052] The data processing unit 9 is used to obtain the projection information generated in the light receiving unit 7 after the light beam or light curtain generated by the light generating unit 6 is blocked by the wafer, or to obtain the projection information generated in the light receiving unit 7 after the light beam or light curtain generated by the light generating unit 6 is blocked by the wafer and the wafer clamping unit, and to judge whether the wafer clamping unit holds a wafer based on the projection information, or to judge whether the wafer clamped by the wafer clamping unit is horizontal based on the projection information, or to judge the state of the wafer clamping unit based on the projection information, or to judge the state of the wafer clamping unit, whether the wafer clamping unit holds a wafer, and whether the wafer clamped by the wafer clamping unit is horizontal based on the projection information.

[0053] Specifically, the projection information acquired by the data processing unit 9 is the width value or area value of the light beam generated by the light generating unit 6 or the blocked area of ​​the light curtain.

[0054] To facilitate data transmission, a signal processing amplifier 8 is provided between the data processing unit 9 and the light receiving unit 7. This amplifier is used to convert the electrical signal from the light receiving unit 7 to a power level that meets the conversion processing requirements. The signal processing amplifier 8 feeds back the optical signal received by the light receiving unit 7 to a host computer, which then performs corresponding operations. In some embodiments, the light receiving unit 7 and the signal processing amplifier 8 can be integrated into a single device.

[0055] In this embodiment, the wafer clamping unit includes a wafer clamping jaw base 3, a base drive motor 4 for driving the wafer clamping jaw base 3 to rotate about its own axis, and at least three wafer clamping jaws 1 mounted on the wafer clamping jaw base 3. A data processing unit can obtain the motor angle value of the base drive motor 4 in real time. A cleaning liquid transmission pipeline 5 is provided above the wafer 2. Specifically, the wafer clamping jaws 1 are partially located within the light beam or light curtain generated by the light generating unit 6.

[0056] When wafer 2 is normally positioned horizontally on wafer holding jaws 1, wafer 2 is located within the light beam or light curtain generated by light generating unit 6, and the plane of wafer 2 is parallel to or at a certain angle to the light beam or light curtain. Of course, light generating unit 6 and light receiving unit 7 can also be arranged parallel to or substantially parallel to the plane of wafer 2, without limitation.

[0057] Specifically, as shown in Figure 3, when the wafer is placed horizontally, the light beam or light curtain generated by the light generating unit 6 is partially blocked by the wafer, and the light receiving unit 7 receives the incomplete light beam or light curtain, that is, the wafer generates a projection on the photosensitive element of the light receiving unit 7. The signal processing amplifier 8 converts the electrical signal from the light receiving unit 7 to a power level that meets the conversion processing requirements and transmits it to the host computer. The width of the projection (blocked light beam or light curtain) at this time is recorded as h w1 As shown in Figure 4, under actual working conditions, the wafer enters the CMP cleaning and drying module and is placed on the wafer fixing clamp 1. The light generating unit 6 and the light receiving unit 7 are working. If the light beam or light curtain received by the light receiving unit 7 is blocked, the signal processing amplifier 8 converts the electrical signal from the light receiving unit 7 to a power level that meets the conversion processing requirements and transmits it to the host computer. The width of the projection (blocked light beam or light curtain) at this time is recorded as h w2 In other words, the projected width value can be used to determine whether the wafer is level.

[0058] In FIG5 , when the wafer fixing clamp 1 is in state 1 (the wafer fixing clamp is fully opened), the wafer fixing clamp 1 can hold the wafer 2 or not, and there is no specific restriction. The light beam or light curtain generated by the light generating unit 6 is partially blocked by the wafer fixing clamp, and the light receiving unit 7 receives the incomplete light beam or light curtain, that is, the wafer fixing clamp generates a projection on the photosensitive element of the light receiving unit 7. The signal processing amplifier 8 converts the electrical signal from the light receiving unit 7 to a power level that meets the conversion processing requirements and transmits it to the host computer. The width of the projection (blocked light beam or light curtain) at this time is recorded as h c1 As shown in Figure 6, when the wafer fixing clamp 1 is in state 2 (wafer fixing clamp closed state), the light beam or light curtain generated by the light generating unit 6 is partially blocked by the wafer fixing clamp, and the light receiving unit 7 receives the incomplete light beam or light curtain, that is, the wafer fixing clamp generates a projection on the photosensitive element of the light receiving unit 7. The signal processing amplifier 8 converts the electrical signal from the light receiving unit 7 to a power level that meets the conversion processing requirements and transmits it to the host computer. The width of the projection (blocked light beam or light curtain) at this time is recorded as h c2 In other words, the wafer fixing clamp 1 can be judged to be in different states by the projected width value.

[0059] A method for detecting a CMP cleaning and drying module is implemented based on the above-mentioned wafer detection device, and comprises the following steps:

[0060] The light generating unit and the light receiving unit are placed parallel to or at a certain angle relative to the plane where the wafer is located, the wafer clamping unit is located between the light generating unit and the light receiving unit, and at least part of the wafer and the wafer clamping unit are located within the light beam or light curtain generated by the light generating unit; specifically, the wafer fixing claw portion of the wafer clamping unit is located within the light beam or light curtain generated by the light generating unit;

[0061] When the wafer is placed horizontally, the projection information of the light beam generated by the light generating unit or the light curtain generated by the light receiving unit is obtained;

[0062] When the wafer clamping unit is in an open state, obtaining projection information of the light beam generated by the light generating unit or the light curtain generated on the light receiving unit;

[0063] Specifically, when the wafer is placed horizontally and the wafer clamping unit is in an open state, the wafer clamping unit rotates to obtain a rotation interval according to a set reference value. The set reference value rotation interval ensures that all wafer fixing claws pass through the light beam or light curtain emitted by the light generating unit. The projection information 1 and projection information 2 obtained by the light receiving unit within the set reference value rotation interval are obtained. The time or motor rotation angle is used as the horizontal axis and the projection information is used as the vertical axis to draw a curve ρ0 as a reference curve;

[0064] More specifically, first, when the wafer 2 is placed horizontally and the wafer fixing clamp 1 is open, the base drive motor 4 is rotated to a certain angle φ (it is necessary to ensure that the angle φ can make all the wafer fixing clamps 1 pass through the light beam or light curtain range), and the width parameters of the blocked light beam or light curtain received by the light receiving unit 7 within the angle range are recorded. According to the angle recorded by the base drive motor 4, the angle φ is divided into different areas, referring to Figure 8, where The angle range is the detection range of wafer 2. The angle range is the detection range of wafer fixing clamp 1. is the interval angle of each wafer 2 detection interval or wafer fixed clamp 1 detection interval, During the rotation process, the angle of the wafer 2 detection zone or the wafer fixed clamp 1 detection zone is the minimum angle of the light beam or light curtain. The average value of the internal data is d1 (which can reflect the wafer thickness parameter).

[0065] Of course, in other embodiments, the rotation angle φ of the base drive motor 4 may also be a certain time period T during the rotation of the base drive motor 4 .

[0066] When the wafer is in a minimum tilt state that does not meet the requirements, the projection information of the light beam generated by the light generating unit or the light curtain generated by the light receiving unit is obtained. The minimum tilt state of the wafer that does not meet the requirements is that under clean and dry conditions, the wafer clamping unit drives the tilted wafer to rotate, and the centrifugal force applied to the wafer just exceeds the restraining force, causing it to leave the limited position. At this time, the tilt state of the wafer is the minimum tilt state that does not meet the requirements.

[0067] Specifically, when the wafer is in a minimum tilt state that does not meet the requirements and the wafer clamping unit is in an open state, the wafer clamping unit rotates a reference value set to obtain a rotation interval. The set reference value obtains a rotation interval to ensure that all wafer fixing claws pass through the light beam or light curtain emitted by the light generating unit, and obtains the projection information 2 and projection information 3 obtained by the light receiving unit within the rotation interval. The curve ρ1 is drawn with time or motor rotation angle as the horizontal axis and projection information as the vertical axis;

[0068] When the wafer clamping unit is in a closed state, obtaining projection information of the light beam generated by the light generating unit or the light curtain generated on the light receiving unit;

[0069] Specifically, when the wafer is placed horizontally and a single wafer fixing clamp of the wafer clamping unit is in a closed state, the wafer clamping unit rotates a set reference value to obtain a rotation interval. The set reference value to obtain the rotation interval ensures that all wafer fixing clamps pass through the light beam or light curtain emitted by the light source. The projection information 1 and projection information 4 obtained by the light receiving unit within the set reference value rotation interval are obtained, and a curve ρ2 is plotted with time or motor rotation angle as the horizontal axis and projection information as the vertical axis.

[0070] The data processing unit determines whether the wafer clamping unit holds a wafer and / or determines whether the wafer clamped by the wafer clamping unit is horizontal and / or status information of the wafer clamping unit based on the acquired projection information 1, projection information 2, projection information 3, and projection information 4;

[0071] Specifically, according to the curve ρ0, the set reference value acquisition rotation interval is divided into a wafer detection angle interval, a wafer fixing clamp detection angle interval, each wafer detection angle interval, or an interval angle of each wafer fixing clamp detection angle interval; in this embodiment, the set reference value acquisition rotation interval is a base drive motor rotation angle interval, or a base drive motor rotation time interval;

[0072] According to the curve ρ0, the average value of the projection information within the wafer detection angle range is d1, and this reference value can be used as a reference value for wafer thickness. Under working conditions, if the detection rotation range is set If the difference between the average value of several data sets selected in the inner wafer detection angle range and d1 exceeds the set threshold, it means that the wafer does not exist. If the difference with d1 is within the set threshold range, it means that the wafer exists, and the wafer presence detection is achieved at this time;

[0073] According to the curves ρ0 and ρ1, the wafer tilt judgment reference value p is determined w , record the set reference value to obtain the projection information within the rotation interval that is greater than the reference value p w The number of data is x w0 In this embodiment, p w is 2 / 3 of the peak value of the ρ0 curve; under working conditions, record the number of wafer detection angles within the set detection rotation range that is greater than the reference value p w The number of data is x w1 , if x w1 with x w0 If the difference between x and w1 with x w0 If the difference is within the set threshold, it means the wafer is level, and wafer tilt detection is achieved.

[0074] According to the curves ρ0 and ρ2, the reference value p of the wafer fixing clamp is determined. c , record the set reference value to obtain the projection information within the rotation interval that is greater than the reference value p c The number of data is x c0 In this embodiment, p c is 49 / 50 of the peak value of the ρ0 curve; under working conditions, the detection angle range of the wafer fixed clamp within the set detection rotation range is greater than the reference value p c The number of data is x c1 , if x c1 with x c0 If the difference between x and x exceeds the set threshold, it means that one or more wafer clamps are closed. c1 with x c0 If the difference is within the threshold range, it means that the wafer clamping jaws are all in the open state, and the wafer clamping jaw state detection is realized. In particular, according to x c1 with x c0 The size of the difference can be used to obtain the number of wafer fixing clamps in the closed state.

[0075] The data processing unit can also calculate the tilt angle θ of the wafer relative to the light beam or light curtain based on the acquired projection information 1 and the projection information of the wafer detection angle range under the working conditions. The wafer width is defined as D and the wafer thickness is defined as d. At a certain moment within the rotation setting angle, the width of the light beam or light curtain blocked is H1, as shown in Figure 7, H1 = h1 + h2 = D·sinθ + d·cosθ ， The wafer tilt angle can be obtained As the wafer rotates with the motor, the tilt angle θ of the wafer relative to the light beam or light curtain can be obtained in real time. t , according to θ t The change of the value can be used to obtain the tilt shape of the wafer, which can be used as a reference for judgment.

[0076] As shown in FIG9 , when the detection device and method of the present invention are applied under actual working conditions, it is first determined whether the wafer to be processed at this moment is the first wafer in the process flow. If it is the first wafer, it is impossible to confirm whether the wafer fixing jaws of the wafer clamping unit are abnormal before the first wafer is placed. The detection method should be applied first to determine the opening and closing state of the wafer fixing jaws. If the wafer fixing jaws are abnormal, specifically one or several wafer fixing jaws are in a closed state, the working condition is stopped and corresponding disposal measures are taken; if the wafer fixing jaws are normal, specifically all wafer fixing jaws are in an open state, the first wafer is placed and the process is carried out. Wafer status detection (wafer presence and level detection). If the wafer status is abnormal, specifically the wafer is missing or the wafer is tilted at an angle exceeding the set range, the operation is stopped and corresponding treatment measures are taken; if the wafer status is normal, specifically the wafer exists and is level, the wafer cleaning and drying process is carried out; after the cleaning and drying process is completed and before the wafer is taken out, the opening and closing status of the wafer fixing jaws is judged again. If the wafer fixing jaws are abnormal, specifically one or several wafer fixing jaws are in a closed state, the operation is stopped and corresponding treatment measures are taken; if the wafer fixing jaws are normal, specifically all wafer fixing jaws are in an open state, the wafer is taken out.

[0077] If it is the n+1th (n>0) wafer, since the opening and closing status of the wafer fixing clamp has been determined before the previous wafer is taken out, there is no need to repeatedly determine the status of the wafer fixing clamp before placing this wafer. Therefore, this detection can be omitted, and the subsequent steps are the same as the detection steps of the first wafer in the process flow.

[0078] The above specific embodiments are used to illustrate the present invention rather than to limit the present invention. Any modifications and changes made to the present invention within the spirit of the present invention and the protection scope of the claims shall fall within the protection scope of the present invention.

Claims

1. A detection device for a CMP cleaning and drying module, characterized in that: include: A light generating unit, used for generating a light beam or a light curtain; A light receiving unit, used for receiving the light beam or light curtain generated by the light generating unit and converting the light signal into an electrical signal; A wafer clamping unit, used for clamping the wafer and driving the wafer to rotate, located between the light generating unit and the light receiving unit, and at least partially in the light beam or light curtain generated by the light generating unit, and the wafer clamping unit has at least a closed state and an open state; A data processing unit is used to obtain projection information generated on a light receiving unit after the light beam or light curtain generated by the light generating unit is blocked by a wafer and / or a wafer clamping unit, and to determine whether the wafer clamping unit holds a wafer and / or whether the wafer clamped by the wafer clamping unit is horizontal and / or status information of the wafer clamping unit based on the projection information.

2. The detection device according to claim 1, characterized in that: The wafer clamping unit comprises a wafer fixing clamping claw base, a base driving motor for driving the wafer fixing clamping claw base to rotate around its own axis, and at least three wafer fixing clamping claws arranged on the wafer fixing clamping claw base.

3. The detection device according to claim 2, characterized in that: The data processing unit can obtain the motor angle value of the base drive motor in real time.

4. The detection device according to claim 1, characterized in that: The projection information acquired by the data processing unit is the width value or area value of the light beam generated by the light generating unit or the blocked area of ​​the light curtain.

5. The detection device according to claim 1, characterized in that: A signal processing amplifier is provided between the data processing unit and the light receiving unit, and is used to convert the electrical signal from the light receiving unit to a power level that meets the conversion processing requirements.

6. A detection method for a CMP cleaning and drying module, characterized in that: The following steps are involved: The light generating unit and the light receiving unit are placed parallel to or at a certain angle relative to the plane where the wafer is located, the wafer clamping unit is located between the light generating unit and the light receiving unit, and at least part of the wafer and the wafer clamping unit are located within the light beam or light curtain generated by the light generating unit; When the wafer is placed horizontally, the projection information of the light beam generated by the light generating unit or the light curtain generated by the light receiving unit is obtained; When the wafer clamping unit is in an open state, obtaining projection information of the light beam generated by the light generating unit or the light curtain generated by the light receiving unit; When the wafer is in the minimum tilt state that does not meet the requirements, the light beam or light curtain generated by the light generating unit is obtained. The projection information three generated by the light receiving unit; When the wafer clamping unit is in a closed state, obtaining projection information of the light beam generated by the light generating unit or the light curtain generated by the light receiving unit; The data processing unit determines whether the wafer clamping unit holds a wafer and / or determines whether the wafer clamped by the wafer clamping unit is horizontal and / or the status information of the wafer clamping unit based on the acquired projection information one, projection information two, projection information three and projection information four.

7. The detection method according to claim 6, characterized in that: The minimum tilt state of the wafer that does not meet the requirements is that under clean and dry conditions, the wafer clamping unit drives the tilted wafer to rotate, and the centrifugal force on the wafer just exceeds the restraining force, causing it to leave the limited position. At this time, the tilt state of the wafer is the minimum tilt state that does not meet the requirements.

8. The detection method according to claim 7, characterized in that: The following steps are involved: The light generating unit and the light receiving unit are placed parallel to or at a certain angle relative to the plane where the wafer is located, the wafer clamping unit is located between the light generating unit and the light receiving unit, and the wafer and the wafer fixing claw part of the wafer clamping unit are located within the light beam or light curtain generated by the light generating unit; When the wafer is placed horizontally and the wafer fixing jaws of the wafer clamping unit are in an open state, the wafer clamping unit rotates to obtain a rotation interval according to a reference value set. The reference value set to obtain the rotation interval ensures that all wafer fixing jaws pass through the light beam or light curtain emitted by the light generating unit. The reference value set to obtain projection information 1 and projection information 2 obtained by the light receiving unit within the rotation interval are obtained. The time or motor rotation angle is used as the horizontal axis and the projection information is used as the vertical axis to draw a curve ρ0 as a reference curve; When the wafer is in the minimum tilt state that does not meet the requirements, and the wafer fixing jaws of the wafer clamping unit are in the open state, the wafer clamping unit rotates the reference value set to obtain the rotation interval, and the reference value set to obtain the rotation interval ensures that all wafer fixing jaws pass through the light beam or light curtain emitted by the light generating unit, and obtain the reference value set to obtain the projection information 2 and projection information 3 obtained by the light receiving unit within the rotation interval, with time or motor rotation angle as the horizontal axis and projection information as the vertical axis, and draw a curve ρ1; When the wafer is placed horizontally and a single wafer fixing clamp of the wafer clamping unit is in a closed state, the wafer clamping unit rotates to obtain a rotation interval according to a reference value set. The rotation interval of the reference value set ensures that all wafer fixing clamps pass through the light beam or light curtain emitted by the light source, and the projection information 1 and projection information 4 obtained by the light receiving unit within the rotation interval are obtained by obtaining the reference value set. The time or the motor rotation angle is used as the horizontal axis and the projection information is used as the vertical axis to draw a curve ρ2; According to the curve ρ0, the set reference value acquisition rotation interval is divided into a wafer detection angle interval, a wafer fixed clamping jaw detection angle interval, each wafer detection angle interval or each wafer fixed clamping jaw detection angle interval interval angle; According to the curve ρ0, the average value of the projection information 1 in the wafer detection angle interval is obtained as d1, and this reference value can be used as a reference value for wafer thickness; under working conditions, if the difference between the average value of several data sets selected in the wafer detection angle interval within the set detection rotation interval and d1 exceeds the set threshold, it means that the wafer does not exist; if the difference with d1 is within the set threshold range, it means that the wafer exists; According to the curves ρ0 and ρ1, the wafer tilt judgment reference value p is determined w , remember the set reference value to obtain the projection information within the rotation interval that is greater than the reference value p w The number of data is x w0 ; Under working conditions, record the wafer detection angle range within the set detection rotation range that is greater than the reference value p w The number of data is x w1 , if x w1 With x w0 If the difference between x and w1 With x w0 If the difference is within the set threshold, it indicates the wafer level; According to the curves ρ0 and ρ2, the reference value p of the wafer fixing clamp is determined c , remember the set reference value to obtain the projection information within the rotation interval that is greater than the reference value p c The number of data is x c0 ; Under working conditions, record the detection angle range of the wafer fixed clamp within the detection rotation range that is greater than the reference value p c The number of data is x c1 , if x c1 With x c0 If the difference between x and x exceeds the set threshold, it means that one or more wafer clamps are closed. c1 With x c0 If the difference is within the threshold range, it means that the wafer fixing jaws are all in the open state.

9. The detection method according to claim 8, characterized in that: The p w is 2 / 3 of the peak value of the ρ0 curve; c It is 49 / 50 of the peak value of the ρ0 curve.

10. The detection method according to claim 6, characterized in that: The data processing unit calculates the tilt angle θ of the wafer relative to the light beam or the light curtain according to the acquired projection information 1 and the projection information of the wafer detection angle range under the working condition.

11. The detection method according to claim 10, characterized in that: The width of the wafer is D, the thickness of the wafer is d, and at a certain moment within the rotation setting angle, the light beam or light curtain is blocked by a width of H1, then the wafer tilt angle at this time is:

12. The wafer inspection method according to claim 8, characterized in that: The set reference value acquisition rotation interval is a rotation angle interval of the base drive motor, or a rotation time interval of the base drive motor.

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