Wafer transfer position adjustment system and method
By combining laser sensors and a main control module, the wafer position is monitored and adjusted in real time, solving the problem of wafer transfer position deviation in RTP equipment, improving process stability and production efficiency, and reducing scrap rate.
Patent Information
- Application Number
- CN202511678557.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-17
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2045-11-17
AI Technical Summary
During long-term operation, existing RTP equipment suffers from wafer transfer position deviations due to factors such as robotic arm drift and thermal deformation, affecting process uniformity and device performance. Existing offline calibration methods cannot detect and correct these deviations in a timely manner, resulting in low production efficiency and potential quality issues.
A laser sensor is used to monitor the wafer position in real time, and the wafer position is automatically adjusted by the main control module and the wafer displacement structure to achieve real-time calibration without manual intervention and improve process stability.
By combining laser sensors and the main control module, high-precision automatic adjustment of wafer transfer position is achieved, which improves process uniformity and product yield, reduces equipment downtime, and lowers scrap rate.
Smart Images
Figure CN121171957B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of semiconductor manufacturing, and particularly relates to a wafer conveying position adjusting system and method. BACKGROUND
[0002] As an advanced semiconductor technology, rapid thermal process (RTP) can heat a wafer to a very high target temperature (600-1300℃) in a very short time. Since the uniformity of the heat field directly affects the process result, in order to ensure the uniform heating of the wafer, the wafer is conveyed into the center position of the base inside the process chamber by a mechanical arm. However, as the equipment runs for a long time, the wafer conveying precision will be poor due to factors such as mechanical arm drift and thermal deformation, which will cause the wafer conveying position deviation when the wafer is conveyed, resulting in the change of the relative position of the wafer and the heat field, thereby causing the temperature gradient, leading to the non-uniformity of the key parameters such as film thickness and doping activation rate, and seriously affecting the process stability and device performance.
[0003] Currently, the calibration of the RTP equipment usually adopts an offline and manual mode, and the operator needs to open the process chamber, use a calibration tooling (simulated wafer) to observe the mark points by repeatedly placing the wafer several times, and repeatedly adjust the programming position parameters of the mechanical arm, so as to calibrate the wafer position. Since the calibration time is long, the equipment running up time is affected, and the work efficiency is low. Due to factors such as mechanical arm drift, thermal deformation, and component wear during long-term operation of the equipment, the wafer conveying position will gradually deviate. The existing offline calibration mode cannot timely find and correct such drift, and can only be remedied after the problem appears (such as poor process uniformity or wafer collision), which increases the production risk and quality hidden danger. SUMMARY
[0004] Based on the technical problems existing in the prior art, the present application provides a wafer conveying position adjusting system and method, which can monitor and adjust the position of the wafer in real time, and ultimately improve the process uniformity and product yield.
[0005] To achieve the above-mentioned purpose, in a first aspect, the present application provides a wafer conveying position adjusting system, comprising an edge ring, a wafer displacement structure and a main control module, the edge ring is used for placing a wafer to be adjusted, a plurality of laser sensors are uniformly arranged on the edge ring above the wafer along the circumference of the wafer, the wafer displacement structure is used for adjusting the position of the wafer on the edge ring, the signal output end of the plurality of laser sensors is electrically connected with the signal input end of the main control module, and the signal output end of the main control module is electrically connected with the signal input end of the wafer displacement structure.
[0006] The further improvement of the present application is that a positioning assembly is further included, which is fixedly arranged above the edge ring, and the plurality of laser sensors are mounted on the positioning assembly.
[0007] The further improvement of the present application is that the radius of the circumference surrounded by the plurality of laser sensors is less than or equal to the radius of the wafer.
[0008] The further improvement of the present application is that the number of the plurality of laser sensors is at least three, and the emission direction of the plurality of laser sensors is vertically downward.
[0009] In the second aspect, the present application provides a wafer conveying position adjustment method based on the wafer conveying position adjustment system, which comprises the following steps:
[0010] The wafer is placed on the edge ring through the wafer displacement structure;
[0011] The plurality of reflected light intensity signals are acquired through the plurality of laser sensors;
[0012] The main control module acquires the plurality of reflected light intensity signals, judges whether adjustment is needed according to the plurality of reflected light intensity signals and a preset calibration signal, and ends the adjustment process when it is judged that no adjustment is needed;
[0013] When it is judged that adjustment is needed, the offset coordinates of the wafer in a preset two-dimensional rectangular coordinate system are calculated according to the plurality of reflected light intensity signals and the calibration signal;
[0014] The main control module generates a control instruction according to the offset coordinates;
[0015] The wafer displacement structure acquires the control instruction and adjusts the position of the wafer according to the control instruction.
[0016] The further improvement of the present application is that in the step of calculating the offset coordinates of the wafer in the preset two-dimensional rectangular coordinate system according to the plurality of reflected light intensity signals and the calibration signal, the step specifically comprises:
[0017] A plurality of radial distances with the origin of the preset two-dimensional rectangular coordinate system as the center are calculated according to the calibration signal and the plurality of reflected light intensity signals;
[0018] The plurality of radial distances are decomposed on the preset two-dimensional rectangular coordinate system to obtain the offset coordinates.
[0019] The further improvement of the present application is that the method further comprises the following steps:
[0020] The reflected light intensity signal of the wafer after adjustment is acquired through the plurality of laser sensors, which is recorded as a calibration signal;
[0021] Calculate the offset coordinates of the wafer at this time according to the calibration signal, denoted as calibration coordinates;
[0022] Compare the calibration coordinates with the error range;
[0023] When the calibration coordinates do not belong to the error range, the host module generates a calibration signal according to the calibration coordinates;
[0024] Send the calibration signal to the wafer displacement structure;
[0025] The wafer displacement structure adjusts the position of the wafer according to the calibration signal;
[0026] Repeat the above steps until the calibration coordinates belong to the error range or the maximum number of calibrations is reached.
[0027] A further improvement of the present application is that the preset two-dimensional rectangular coordinate system takes the center of the edge ring as the coordinate origin;
[0028] The calibration signal is the reflected light intensity signal of the plurality of laser sensors when the center of the wafer is at the coordinate origin.
[0029] The above technical solution has the following beneficial technical effects:
[0030] The present application detects whether the wafer is offset by the reflected light intensity signal obtained by the plurality of laser sensors, processes the reflected light intensity signal by the host module, thereby controlling the wafer displacement component to adjust the position of the wafer, and placing the wafer by the edge ring, thereby adjusting the wafer transfer position in real time without manual intervention in the process chamber, effectively improving the process stability. BRIEF DESCRIPTION OF DRAWINGS
[0031] The accompanying drawings serve to better understand the present application and do not constitute an undue limitation on the present application. Among them:
[0032] Figure 1 is a structural schematic diagram of a wafer transfer position adjustment system of the present application;
[0033] Figure 2 is a partial enlarged view of the edge ring in a wafer transfer position adjustment system of the present application;
[0034] Figure 3 is a schematic diagram of three laser sensors in an embodiment of a wafer transfer position adjustment method of the present application;
[0035] Figure 4 is a schematic diagram of four laser sensors in an embodiment of a wafer transfer position adjustment method of the present application.
[0036] In the figure: 1, laser sensor; 2, positioning assembly; 3, wafer; 4, edge ring; 401, outer ring; 402, inner ring; 5, wafer displacement structure. DETAILED DESCRIPTION
[0037] Exemplary embodiments of the present application are described herein with reference to the drawings, in which various details are set forth to facilitate an understanding of the present application. However, it will be apparent to one of ordinary skill in the art that various changes and modifications can be made without departing from the spirit and scope of the present application. Thus, the present application is not intended to be limited to the embodiments described herein but is to be accorded the widest scope possible as defined by the claims and equivalents thereof.
[0038] Embodiment One
[0039] A wafer film-transport position adjustment system, such as Figure 1As shown, it comprises a plurality of laser sensors 1, a positioning assembly 2, an edge ring 4, a wafer displacement structure 5 and a master control module, the positioning assembly 2 is arranged above the edge ring 4, the plurality of laser sensors 1 are installed on the positioning assembly 2, the plurality of laser sensors 1 are evenly arranged on the positioning assembly 2 along the circumference of the wafer 3, the wafer displacement structure 5 is used to adjust the position of the wafer 3 on the edge ring 4, the signal output end of the plurality of laser sensors 1 is electrically connected with the signal input end of the master control module, the signal output end of the master control module is electrically connected with the signal input end of the wafer displacement structure 5, and the edge ring 4 is used to place the wafer 3 to be adjusted. The plurality of laser sensors 1 are used to emit reference light to the wafer 3 and receive the reflected light intensity signals reflected by the wafer 3 and the edge ring 4. The positioning assembly 2 is used to install the plurality of laser sensors 1. The wafer displacement structure 5 is used to place the wafer 3 into the edge ring 4 and adjust the position of the wafer 3. The master control module is used to acquire the plurality of reflected light intensity signals, generate a control instruction according to the plurality of reflected light intensity signals, and send the control instruction to the wafer displacement structure 5, so as to control the wafer displacement structure 5 to adjust the position of the wafer 3. The plurality of laser sensors 1 are used to simultaneously acquire the reflected light intensity of the wafer 3 and the edge ring 4 in a non-contact manner, and then indirectly acquire the position information of the wafer 3, convert the geometric information into quantifiable electrical signals, and avoid particle pollution and fragmentation risk caused by mechanical contact. The positioning assembly 2 provides a rigid reference for the plurality of laser sensors 1, which is evenly distributed along the circumference, so that the reflected light intensity signals of the plurality of laser sensors 1 have comparability and facilitate data fusion, and reduce system errors caused by inclination or height difference. The edge ring 4 is used to support the wafer 3 and also serves as a reference, and when the wafer 3 is offset, the edge ring 4 is used as a reference to adjust the position relationship between the reference and the wafer 3. The wafer displacement structure 5 simplifies the traditional manual centering or two-step mechanical pre-centering into a single-process automation, shortens the adjustment time, improves the production capacity, and reduces the waste rate caused by subsequent process offset. The master control module calculates the offset coordinates in real time and generates a control instruction, realizes the integration of measurement, decision and execution, and improves the universality and intelligent level of the system. The above structures are arranged inside the process chamber, and through the above wafer transmission position adjustment system, the offset of the wafer displacement structure 5 can be corrected in real time without opening the process cavity, high-precision wafer transmission position detection and adjustment can be realized, and the stability of the process can be effectively improved.
[0040] Specifically, the plurality of laser sensors 1 are transceiver integrated laser sensors, which emit reference light to the wafer 3 and receive reflected light reflected by the wafer 3 and the edge ring 4, so as to generate reflected light intensity signals. Compared with transceiver separated laser sensors, the transceiver integrated laser sensors have a compact structure and require a smaller installation space.
[0041] Specifically, the number of the plurality of laser sensors 1 is at least three, preferably three or four. The reflected light intensity signal of each laser sensor 1 corresponds to a coordinate located at the edge of the wafer 3, and the plurality of laser sensors 1 are located on the same circle. Therefore, at least three coordinates are required to obtain the real-time center of the wafer 3, that is, the number of the laser sensors 1 is three. When the number of the laser sensors 1 is three, the included angle between adjacent laser sensors 1 is 120°. When the number of the laser sensors 1 is four, the included angle between adjacent laser sensors 1 is 90°, and the calculation of the offset coordinate is simpler.
[0042] Specifically, as shown in Figure 2 The edge ring 4 includes an outer ring 401 and an inner ring 402. The outer ring 401 is a U-shaped circular ring with an opening downward, and the inner ring 402 is a circular ring. The inner opening end of the outer ring 401 is fixedly connected to the inner ring 402. The U-shaped cross section of the outer ring 401 and the circular design of the inner ring 402 effectively reduce the weight, so that a height difference is formed between the top surface of the inner ring 402 and the outer ring 401, thereby stably placing the wafer 3. The opening direction of the outer ring 401 is downward, and the opening end close to the inner side is fixedly connected to the inner ring 402 (for example, welding, bonding or integrally casting). By setting the inner ring 402 as a circular ring, the contact between the lower bottom surface of the wafer 3 and the edge ring 4 is reduced, thereby avoiding pollution or damage to the wafer 3 during the adjustment process.
[0043] Specifically, the thickness of the inner ring 402 is less than the height of the side wall of the outer ring 401. Therefore, the wafer 3 can be placed in the groove formed by the inner ring 402 and the outer ring 401. Even if the wafer 3 deviates during the placement process or the adjustment process, the side wall of the outer ring 401 can be used for auxiliary guidance to automatically suppress large deviation and control the deviation within the outer ring 401, thereby avoiding the wafer 3 from sliding out of the inner ring 402 or warping, facilitating subsequent adjustment and calibration. The groove formed by the inner ring 402 and the outer ring 401 constitutes a darkroom, which effectively shields the side light and stray light, thereby improving the signal quality and signal-to-noise ratio of the laser sensor 1.
[0044] Specifically, the circumference radius surrounded by the plurality of laser sensors 1 is less than or equal to the radius of the wafer 3, and the emission direction of the plurality of laser sensors 1 is vertically downward. By setting the emission direction of the plurality of laser sensors 1 as vertically downward, the intensity of the reflected light intensity signal is improved, the reflection loss is reduced, and the accuracy of subsequent adjustment is improved. The plurality of laser sensors 1 emit reference light to the wafer 3, and form a light spot on the wafer 3. The circumference radius surrounded by the plurality of laser sensors 1 is preferably slightly smaller than the radius of the wafer 3, so that the center of the light spot falls on the edge position of the wafer 3. By arranging the plurality of laser sensors 1 above the edge area of the wafer 3, it is ensured that the position change of the wafer 3 can cause the area ratio change of different reflectivity areas in the light spot, and then the position of the wafer 3 is judged whether to be offset.
[0045] Specifically, in use, the wafer 3 is first placed on the edge ring 4 by the wafer displacement structure 5, and then the plurality of laser sensors 1 emit reference light to the wafer 3. The reference light irradiates the edge of the wafer 3, and is reflected back to the laser sensor 1 through the wafer 3 and the edge ring 4. The plurality of laser sensors 1 obtain a plurality of reflected light intensity signals, and then upload the reflected light intensity signals to the main control module. The main control module compares the reflected light intensity signals with the preset calibration signals. When the deviation between the reflected light intensity signals and the preset calibration signals is greater than a first threshold value, it is judged that adjustment is needed, otherwise adjustment is not needed. The preset calibration signal is the reflected light intensity signal of each laser sensor 1 when the wafer 3 is aligned. The first threshold value is set according to the required accuracy of the wafer 3. When it is judged that adjustment is needed, the offset coordinates of the wafer 3 in the preset two-dimensional rectangular coordinate system are calculated according to the plurality of reflected light intensity signals and the calibration signal. The origin of the preset two-dimensional rectangular coordinate system is the center of the edge ring 4, which is also the alignment target of the wafer 3. The main control module generates a control instruction according to the offset coordinates, and sends the control instruction to the wafer displacement structure 5. The wafer displacement structure 5 adjusts the position of the wafer 3 according to the control instruction. After the first adjustment, secondary judgment is made according to the signals of the laser sensors 1. If it is still judged that adjustment is needed, the above steps are repeated until it is judged that adjustment is not needed or the maximum calibration times are reached. When the maximum calibration times are reached, it indicates that a special situation occurs, and an alarm needs to be sent for manual debugging. The special situation includes but is not limited to failure of the plurality of laser sensors 1 or other equipment failure.
[0046] Specifically, the wafer displacement structure 5 is a mechanical arm or a mechanical hand commonly used in a process chamber, or other structures or components that can adjust the position of the wafer 3 according to instructions.
[0047] Embodiment 2
[0048] A wafer transmission position adjustment method based on a wafer transmission position adjustment system in embodiment 1, comprising the following steps:
[0049] Obtain a plurality of reflected light intensity signals through the plurality of laser sensors 1;
[0050] The main control module obtains a plurality of reflected light intensity signals, judges whether adjustment is needed according to the plurality of reflected light intensity signals and a preset calibration signal, and ends the adjustment process when it is judged that no adjustment is needed;
[0051] When it is judged that adjustment is needed, the offset coordinates of the wafer 3 in a preset two-dimensional rectangular coordinate system are calculated according to the plurality of reflected light intensity signals and the calibration signal;
[0052] The main control module generates a control instruction according to the offset coordinates;
[0053] The wafer displacement structure 5 obtains the control instruction and adjusts the position of the wafer 3 according to the control instruction.
[0054] In the adjustment process, the wafer 3 is first placed on the edge ring 4 by the wafer displacement structure 5, then the plurality of laser sensors 1 emit reference light to the wafer 3, the reference light is irradiated on the edge of the wafer 3, and is reflected back to the laser sensor 1 through the wafer 3 and the edge ring 4, the plurality of laser sensors 1 obtain a plurality of reflected light intensity signals, and then upload the reflected light intensity signals to the main control module, the main control module compares the reflected light intensity signals with the preset calibration signal, judges that adjustment is needed when the deviation between the reflected light intensity signals and the preset calibration signal is greater than a first threshold, otherwise adjustment is not needed, the preset calibration signal is the reflected light intensity signal of each laser sensor 1 when the wafer 3 is aligned, and the first threshold is set according to the required accuracy of the wafer 3, when it is judged that adjustment is needed, the offset coordinates of the wafer 3 in a preset two-dimensional rectangular coordinate system are calculated according to the plurality of reflected light intensity signals and the calibration signal, the origin of the preset two-dimensional rectangular coordinate system is the center of the edge ring 4, which is also the alignment target of the wafer 3, the main control module generates a control instruction according to the offset coordinates, and sends the control instruction to the wafer displacement structure 5, and the wafer displacement structure 5 adjusts the position of the wafer 3 according to the control instruction. After the first adjustment, secondary judgment is performed according to the signals of the laser sensors 1, if it is still judged that adjustment is needed, the above steps are repeated until it is judged that adjustment is not needed or the maximum calibration times are reached, when the maximum calibration times are reached, it means that a special situation occurs in a dead loop, at this time, an alarm needs to be sent for manual debugging, and the special situation includes but is not limited to faults in the plurality of laser sensors 1 or other equipment faults.
[0055] Specifically, the step of calculating the offset coordinates of the wafer 3 in the preset two-dimensional rectangular coordinate system according to the plurality of reflected light intensity signals and the calibration signal specifically comprises the following steps:
[0056] According to the calibration signal and the plurality of reflected light intensity signals, a plurality of radial distances with the origin of the preset two-dimensional rectangular coordinate system as the center are calculated.
[0057] The plurality of radial distances are decomposed on the preset two-dimensional rectangular coordinate system to obtain the offset coordinates.
[0058] Specifically, the radial distance D n is calculated according to the following formula:
[0059] D n = K (I n -I n_ref ) + D n_ref ;
[0060] In the formula, D n represents the radial distance of the light spot of the nth laser sensor to the edge of the wafer in real time; K represents a proportional coefficient; I n represents the reflected light intensity value received by the nth laser sensor, that is, the reflected light intensity signal; I n_ref represents the reflected light value received by the nth laser sensor when the wafer is in the reference position, that is, the calibration signal; D n_ref represents the reference distance from the light spot of the nth laser sensor to the edge of the wafer when the wafer is in the reference position. The value of K is obtained by fitting the parameters and adjustment process data of the plurality of laser sensors during the wafer adjustment process.
[0061] In the formula, the reference distance from the light spot of the nth laser sensor to the edge of the wafer when the wafer is in the reference position is obtained by calculating the difference between the radius of the wafer and the radius of the circle surrounded by the plurality of laser sensors.
[0062] Specifically, the following steps are further included:
[0063] Obtain the reflected light intensity signal of the adjusted wafer 3 through the plurality of laser sensors 1, denoted as a calibration signal;
[0064] Calculate the offset coordinates of the wafer 3 at this time according to the calibration signal, denoted as a calibration coordinate;
[0065] Compare the calibration coordinate with the error range;
[0066] When the calibration coordinate does not belong to the error range, the main control module generates a calibration signal according to the calibration coordinate;
[0067] Send the calibration signal to the wafer displacement structure 5;
[0068] The wafer displacement structure 5 adjusts the position of the wafer 3 according to the calibration signal;
[0069] Repeat the above steps until the calibration coordinates are within the error range or the maximum number of calibrations is reached.
[0070] Specifically, taking three laser sensors as an example, such as Figure 3 As shown, at this time I n_ref Including: I 1_ref I 2_ref and I 3_ref I n Including: I1, I2, and I3, D n_ref Includes: D 1_ref D 2_ref and D 3_ref D n Including D1, D2, and D3, the reference coordinates O of the wafer. _ref (0, 0), real-time center coordinates O( X, The coordinates of the three laser sensors S1, S2, and S3 are as follows:
[0071] S1: (0, r); S2: (- / 2r, -1 / 2r); S3: ( / 2r, -1 / 2r);
[0072] When the wafer is in the reference position, D n_ref =Rr,D n =K(I n -I n_ref )+D n_ref The center projection coordinates S of the three laser sensors n (X) _Sn Y _Sn The formula for calculating the distance between the wafer and the actual center O of the wafer is as follows:
[0073] (X _Sn - X) 2 +(Y _Sn- Y) 2 =(RD n ) 2 ;
[0074] S1:(0- X) 2 +(r- Y) 2 =(R-D1) 2 ;
[0075] S2:(- r- X) 2 +(-0.5r- Y) 2 =(R-D2) 2 ;
[0076] S3:( r- X) 2 +(-0.5r- Y) 2 =(R-D3) 2 ;
[0077] When the wafer position shifts, by substituting D... n The coordinates of the actual center O of the wafer are calculated, and the wafer displacement structure 5 is controlled to adjust the position of the wafer 3 according to the control command generated based on the actual center of the wafer.
[0078] Specifically, when the number of laser sensors 1 is four, such as Figure 4 As shown, four laser sensors 1 are symmetrically arranged along the XY axes of the preset two-dimensional rectangular coordinate system. Two laser sensors 1 are on each axis, and the two laser sensors 1 on the same axis are symmetrical about the origin. The laser sensors on the X-axis measure signals I1 and I2, and the laser sensors on the Y-axis measure signals I3 and I4. When the wafer 3 is in the reference position, the center of the vertically downward-emitted light spot projection from the laser sensors falls precisely on the edge of the wafer. By arranging the laser sensors in the wafer edge region, it is ensured that changes in the wafer's position can cause changes in the area ratio of different reflectivity regions within the light spot, thereby determining that the wafer's position has shifted. Wafer reflectivity R wafer Edge ring reflectivity R ring The laser sensor emits a light spot with area Φ1 onto the wafer and an emission spot with area Φ2 onto the edge ring. The laser sensor emits a light intensity I. Under the reference condition, after the light enters the cavity from the wafer, it falls onto the edge ring, with the center of the wafer coinciding with the center of the edge ring. At this time, the total light intensity I received by the laser sensor is the superposition of the reflected light from the wafer and the edge ring. The light intensity is calculated as follows:
[0079] X direction:
[0080] X+:I 1_ref =I*[Φ1*R wafer +Φ2*R ring ] ;
[0081] X-:I 2_ref =I*[Φ1*Rwafer+Φ2*R ring ] ;
[0082] Y direction:
[0083] Y+:I 3_ref =I*[Φ1*R wafer +Φ2*R ring ] ;
[0084] Y-:I 4_ref =I*[Φ1*R wafer +Φ2*R ring ] ;
[0085] I 1_ref =I 2_ref =I 3_ref =I 4_ref ;
[0086] When the wafer is in the reference position, D n_ref =Rr, calibrated using experimental data, establish I n With D n Relationship, D n =K(I n -I n_ref )+D n_ref ;
[0087] When the wafer transfer position shifts, the light intensity received by the laser sensor changes, and the energy I received by the laser sensor in real time will be converted into a variable. n Compared with the reference energy I n_ref Compare and calculate D n ;
[0088] X-direction offset: X = 0.5(D1 - D2); Y-direction offset: Y = 0.5(D3-D4), and the data is fed back to the robot controller to adjust the position of the transfer plate accordingly. The specific adjustment method is as follows:
[0089] If the wafer shifts towards the first quadrant, the area of the wafer illuminated by the laser in the X+ and Y+ directions increases (Φ1' > Φ1), while the area illuminated on the edge ring decreases (Φ2' < Φ2).
[0090] The light intensities received by the laser sensor in the X direction are as follows:
[0091] X+:I1=I*[Φ1'*R wafer +Φ2'*R ring ] ;
[0092] X-:I2=I*[Φ1'*R wafer +Φ2'*R ring ] ;
[0093] The light intensities received by the laser sensor in the Y direction are as follows:
[0094] Y+: I3 = I * [Φ1' * R + Φ2' * R] ; wafer ring Y-: I4 = I * [Φ1' * R + Φ2' * R] ; wafer ring
[0095] Y+: I3 = I * [Φ1' * R + Φ2' * R] ; wafer ring Y-: I4 = I * [Φ1' * R + Φ2' * R] ; wafer ring
[0096] 3) At this time, the light intensity I1, I2, I3, I4 received by the laser sensor in the X and Y directions is no longer equal, and the light intensity received by the symmetric pair of laser sensors in the XY direction presents opposite change trend relative to the reference value:
[0097] I1 < I, D1 < D; 1_ref 1_ref I2 > I, D2 > D; 2_ref 2_ref I3 < I, D3 < D; 3_ref 3_ref I4 > I, D4 > D; 4_ref 4_ref
[0098] I1 < I, D1 < D; 1_ref 1_ref I2 > I, D2 > D; 2_ref 2_ref I3 < I, D3 < D; 3_ref 3_ref I4 > I, D4 > D; 4_ref 4_ref
[0099] X = 0.5 (D1-D2) < 0, Y = 0.5 (D3-D4) < 0, X and Y positive and negative can judge the direction of deviation, and the absolute value can be used to calibrate the deviation distance, and (X, Y) is sent to the manipulator controller to control the manipulator to adjust the wafer position. X, Y).
[0100] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above division of each functional unit and module is exemplified, and in actual application, the above functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The above integrated unit can be realized in the form of hardware or software. In addition, the specific names of each functional unit and module are only for easy distinction, and do not limit the protection scope of the present application. The specific working process of the unit and module in the above system can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.
[0101] The foregoing detailed description has set forth various embodiments of the devices and / or processes via the use of specific terminology. However, embodiments thereof can be practiced with the exact description not being presented in detail. The term "device" should be understood to encompass devices operating in various modes, such as active mode, sleep mode, hibernate mode, and the like. The terms "coupled" and "connected," along with their derivatives, can be used. It should be understood that these terms are not intended as synonyms for each other. Rather, particular circuitry that can be said to be coupled or connected can be coupled and connected via some transmission medium.
Claims
1. A wafer transfer position adjustment system, comprising: The wafer position adjustment system comprises an edge ring (4), a wafer displacement structure (5) and a main control module, the edge ring (4) is used for placing a wafer (3) to be adjusted, a plurality of laser sensors (1) are uniformly arranged on the edge ring (4) above along the circumference of the wafer (3), the wafer displacement structure (5) is used for adjusting the position of the wafer (3) on the edge ring (4), the signal output end of the plurality of laser sensors (1) is electrically connected with the signal input end of the main control module, and the signal output end of the main control module is electrically connected with the signal input end of the wafer displacement structure (5); The method for adjusting the wafer position of the wafer position adjustment system comprises the following steps: placing the wafer (3) on the edge ring (4) through the wafer displacement structure (5); acquiring a plurality of reflected light intensity signals through the plurality of laser sensors (1); the main control module acquires the plurality of reflected light intensity signals, judges whether adjustment is needed according to the plurality of reflected light intensity signals and a preset calibration signal, and ends the adjustment process when it is judged that no adjustment is needed; when it is judged that adjustment is needed, the offset coordinates of the wafer (3) in a preset two-dimensional rectangular coordinate system are calculated according to the plurality of reflected light intensity signals and the calibration signal; the main control module generates a control instruction according to the offset coordinates; the wafer displacement structure (5) acquires the control instruction and adjusts the position of the wafer (3) according to the control instruction; in the step of calculating the offset coordinates of the wafer (3) in the preset two-dimensional rectangular coordinate system according to the plurality of reflected light intensity signals and the calibration signal, the following steps are included: a plurality of radial distances with the center being the origin of the preset two-dimensional rectangular coordinate system are calculated according to the calibration signal and the plurality of reflected light intensity signals; the plurality of radial distances are decomposed on the preset two-dimensional rectangular coordinate system to obtain the offset coordinates; acquiring the reflected light intensity signal of the wafer (3) after adjustment through the plurality of laser sensors (1), which is recorded as a calibration signal; calculating the offset coordinates of the wafer (3) at this time according to the calibration signal, which is recorded as calibration coordinates; comparing the calibration coordinates with an error range; when the calibration coordinates do not belong to the error range, the main control module generates a calibration signal according to the calibration coordinates; sending the calibration signal to the wafer displacement structure (5); the wafer displacement structure (5) adjusts the position of the wafer (3) according to the calibration signal; repeating the above steps until the calibration coordinates belong to the error range or the maximum calibration times are reached.
2. The wafer transfer position adjustment system of claim 1, wherein The wafer position adjustment system further comprises a positioning assembly (2) fixedly arranged above the edge ring (4), and the plurality of laser sensors (1) are installed on the positioning assembly (2).
3. The wafer transfer position adjustment system of claim 1, wherein The circumferential radius surrounded by the plurality of laser sensors (1) is less than or equal to the radius of the wafer (3).
4. The wafer transfer position adjustment system of claim 1, wherein The number of the plurality of laser sensors (1) is at least three, and the emission direction of the plurality of laser sensors (1) is vertically downward.
5. The wafer transfer position adjustment system of claim 1, wherein The preset two-dimensional rectangular coordinate system takes the center of the edge ring (4) as the coordinate origin. The calibration signal is the reflected light intensity signal of the plurality of laser sensors (1) when the center of the wafer (3) is at the coordinate origin.
Citation Information
Patent Citations
Wafer loading system, rapid thermal annealing process machine and semiconductor equipment
CN222421938U