WO2016201716A1

WO2016201716A1 - Silicon wafer distribution state image combination detection method and device

Info

Publication number: WO2016201716A1
Application number: PCT/CN2015/082295
Authority: WO
Inventors: 徐冬
Original assignee: 北京七星华创电子股份有限公司
Priority date: 2015-06-17
Filing date: 2015-06-25
Publication date: 2016-12-22
Also published as: CN104979229B; CN104979229A

Abstract

A silicon wafer distribution state image combination detection method and device. The device comprises an image sensing unit (9) disposed above a silicon wafer group (2) and a photoelectric/ultrasonic scanning unit (4,5/6,7) disposed on a manipulator (1), wherein the photoelectric/ultrasonic scanning unit (4,5/6,7), driven by the manipulator (1), carries out horizontal or vertical positioning. In the method, in an image collection mode in a first detection stage, an abnormal state limit position pre-scanning instruction for the protruding silicon wafer is executed; in a mode in which the photoelectric scanning/ultrasonic scanning unit works firstly and then performs self reception and performs ranging in a second detection stage, a cyclic scanning instruction for all silicon wafers above the pre-scanned protruding wafer is carried out; in a third detection stage, the mode is converted into a mutual reception working mode, and a silicon wafer distribution state anomaly scanning instruction is executed; in a fourth detection stage, the mode is again converted into a self reception working mode, and a cyclic scanning instruction for all silicon wafers below the pre-scanned protruding wafer is executed; and multiple scanning and detection points are distributed around a loader (3), thereby further improving the detection precision.

Description

Silicon wafer distribution state image combination detection method and device

Technical field

The present invention relates to the field of semiconductor processing equipment, and in particular, to a silicon wafer distribution state image combined detection method for a semiconductor device carrying region, and to a silicon wafer distribution state image combined detecting device for a semiconductor device carrying region.

technical background

The safe access and transport of silicon wafers is a very important technical indicator for large-scale integrated circuit production. In the production process, the wafer fragmentation rate caused by the transport equipment itself is usually less than one in 100,000. Moreover, as a batch-type silicon wafer heat treatment system, the wafer transfer, wafer placement and wafer take-up times required for each production process are more than that of the monolithic process system, thus the wafer transfer, wafer placement and fetching The security and reliability requirements of the film are higher.

At present, robots are widely used in the field of semiconductor integrated circuit manufacturing technology. The robot is an important device in the silicon wafer transmission system. It is used for access and transport process before and after processing, and it can accept instructions and precision. Positioning to a point in the three-dimensional or two-dimensional space for picking and placing silicon wafers, it is possible to pick and place a single wafer, and to pick and place multiple wafers.

However, when the robot picks up and puts the wafer, especially when the wafer is heated or deformed during the transfer process or heat treatment, the wafer may be in a protruding state on the carrier or in a laminated or inclined manner. In the case of a piece or a piece, there is often a collision that causes the wafer or device to be damaged, causing irreparable damage.

Please refer to FIG. 1. FIG. 1 is a schematic view showing the positional structure of a robot in the prior art during wafer transfer, wafer placement and film taking. As shown, when the silicon wafer in the silicon wafer set 2 is protruding on the carrier 3 When the abnormal state is abnormal, the movement of the robot 1 in the automatic access silicon wafer 2 is in an unsafe working state, which is very likely to cause damage to the silicon wafer 2 and the device (including the robot 1).

Therefore, after the robot 1 completes the placement of the silicon wafer or prepares to take the film, it is necessary to accurately identify the distribution state of the silicon wafer in the silicon wafer group 2 on the carrier 3, and provide an accurate countermeasure for the identified abnormal states. To achieve secure pick and place.

At present, the identification of the distribution state of the silicon wafer in the batch type silicon wafer heat treatment system generally uses a simple photoelectric signal motion scanning method to identify the distribution state of the silicon wafer on the carrier 3, and this scanning method is only for the silicon wafer group 2 When the silicon wafer is in an abnormal state such as a laminated piece, a slanted piece or a pieceless film, it has a certain detection effect, but if the silicon piece is in a protruding state on the carrier 3, it cannot be detected well, that is, through The prior art simply results in abnormal or normal results, and is prone to collision during the motion scanning process, resulting in damage to the silicon wafer or equipment, and often causes false negatives and false positives.

With the development of semiconductor integrated circuit manufacturing technology, higher requirements are placed on the safe access and transport of silicon wafers, that is, the precise control requirements for robots are also increasing. Therefore, how to quickly and accurately detect the distribution state of the silicon wafer in the bearing area of the silicon wafer semiconductor device and avoid damage of the silicon wafer and the device caused by the movement of the robot has become a technical problem to be solved by those skilled in the art.

Summary of invention

A first object of the present invention is to provide a silicon wafer distribution state image combination detecting method for a semiconductor device carrying region, which can quickly and accurately detect the distribution state of the silicon wafer in the carrying region of the silicon semiconductor device, and avoid the silicon wafer and the device caused by the robot movement. damage. A second object of the present invention is to provide a silicon wafer distribution state image combination detecting device for two semiconductor device carrying regions.

In order to achieve the above first object, the present invention provides a silicon wafer of a semiconductor device carrying region. a distributed state image combination detecting method, wherein an image sensing unit is disposed above a silicon wafer set, and first and second photosensors/first and second ultrasonic sensors are disposed on a circumferential side of the carrier Up and moving with the robot; the first and second photosensors/first and second ultrasonic sensors are respectively located at opposite ends of the U-shaped end of the robot; the method comprises:

Step S1: setting a center coordinate of the ideally placed silicon wafer and a deviation threshold of the actual placement area from the center coordinate; starting the image sensing unit to take a picture of the placement state of the silicon wafer, and using the image feature recognition algorithm to determine the placement of the silicon wafer in the silicon wafer group Whether there is a case where the deviation threshold is exceeded; if yes, step S5 is performed, otherwise, step S2 is performed;

Step S2: setting the operating modes of the first and second photosensors/first and second ultrasonic sensors to a self-receiving mode, and the first and second photosensors/first and second ultrasonic sensor positioning corresponding to the carrier a vertical starting point at which the silicon wafer is placed and an image protruding point detected in step S1 as a horizontal starting point position;

Step S3: judging according to the first and/or second photosensors, or the first and/or second ultrasonic sensors, respectively, the time difference of transmitting and receiving the optical signals in the vertical downward direction of the silicon wafer stack and the predetermined judgment rule The silicon wafer has a vertical coordinate that highlights an abnormal state of the specified position;

Step S4: the robot advances a predetermined horizontal step distance along the center of the carrying area to determine whether the position is a horizontal end point position; if yes, step S5 is performed; otherwise, step S3 is performed;

Step S5: setting two photosensors/ultrasonic sensors in an inter-acceptance mode, the robot performs an abnormal scan command of all silicon distribution states from a vertical start position to a vertical end position of the horizontal end point position, according to two photoelectric sensors/ultrasounds The feedback value of the mutual feedback and reception between the sensors is the distribution state of the optical signal intensity in the scanning detection area, and it is judged whether there are slanting sheets, laminations and / or the abnormal state of the blank;

Step S6: setting the two photosensors/ultrasonic sensors in a self-receiving mode, according to the first and/or second photosensors, or the first and/or second ultrasonic sensors, each emitting in a vertical upward direction of the silicon wafer stack And a time difference between the received optical signal and a predetermined determination rule, determining that the silicon wafer has a vertical coordinate that protrudes from the abnormal state of the specified position;

Step S7: the robot advances in a direction opposite to the center of the carrying area by a predetermined horizontal step distance, and determines whether the position is a horizontal starting point position of the image protruding point detected in step S1; if yes, ends; otherwise Go to step S6.

Preferably, the step S5 specifically includes the following steps:

Step S51: obtaining a motion scanning area for judging the oblique piece, the lamination piece and the empty piece according to the thickness of the silicon wafer, the separation distance of the adjacent silicon wafers, and the thickness of the carrier;

Step S52: the robot is positioned at a horizontal motion starting point position and a vertical ending point position;

Step S53: sequentially determining whether the corresponding silicon wafer placement position has a slanting piece according to a preset detection area in which the two photoelectric sensors and/or the ultrasonic scanning unit mutually transmit and receive optical signals and a light signal shielding width in the area. The abnormal state of the lamination and/or the blank; if yes, step S55 is performed; otherwise, step S54 is directly performed;

Step S54: the robot sequentially descends the distance of a silicon wafer to determine whether the position is a vertical end point position; if so, end; otherwise, step S53;

Step S55: The abnormal state information of the oblique piece, the lamination and/or the empty piece is issued at the corresponding position, and step S54 is performed.

Preferably, the carrier or the robot comprises a rotating unit, the rotating unit causes a relative rotational movement of the robot around the carrier, and has N on the entire circumference of the carrier Rotating detection stop positions, performing the steps S1 to S7 once at each detection position to obtain a corresponding set of detection results; finally, performing N operations on the N sets of detection results to obtain an abnormal state distribution of the final silicon wafer tabs. Where N is a positive integer greater than or equal to 2.

Preferably, the rotation angles of the two adjacent ones of the N positions are the same, and the selection is set as follows:

A. When the remainder of (360 ° / set rotation angle) = 0:

Cumulative detection position number = 360 ° / set rotation angle

Actual rotation angle = set rotation angle

B. When the remainder of (360°/set rotation angle) ≠0:

The total number of detected positions = (360 ° / set rotation angle) rounded (after rounding off the decimal point) +1

Actual rotation angle = 360° / number of cumulative detection positions

If the detected position coordinate value generated by the rotation start point and the set rotation angle conflicts with the coordinate position of the carrier support point, the start point and the rotation angle value need to be reset.

Preferably, in the steps S4 and S6, the horizontal step distance of the robot moves in the horizontal direction is equal, gradually becomes larger, and/or gradually decreases; and the horizontal starting position and the silicon wafer are at the falling limit position. The position of the horizontal end point is related to the support structure parameters of the carrier.

In order to achieve the above second object, the present invention further provides a silicon wafer distribution state image scanning detecting device, comprising an image sensing unit, a photoelectric scanning unit, a control unit and an alarm unit; the image sensing unit is disposed at the silicon wafer Above the group, for overhead view, an image laminated on a state in which the silicon wafer is placed in the silicon wafer group; the photoelectric scanning unit is disposed on a robot hand on a circumferential side of the carrier, and moves with the robot, at a level And/or moving in a vertical preset direction and performing scan detection, which includes two photosensors; the photosensors are respectively located at the U-shaped end of the robot For the position, the two photoelectric sensors operate in a self-receiving mode or a mutual receiving mode; the control unit is configured to initiate detection and process the obtained photoelectric intensity and distribution result, and obtain an abnormal state distribution of the silicon wafer on the carrier. Wherein the abnormal state includes a state of a silicon wafer protrusion, a diagonal piece, a lamination, and/or an empty piece; and an alarm unit connected to the control unit, the control unit controlling the said according to an abnormal state distribution situation The opening and closing of the alarm unit.

In order to achieve the above second object, the present invention also provides a silicon wafer distribution state image scanning detecting device, which comprises an image sensing unit, an ultrasonic scanning unit, a control unit and an alarm unit; an image of the image sensing unit state; a scanning unit disposed on a robot hand on a circumferential side of the carrier and moving in a horizontal and/or vertical preset direction and performing scan detection as the robot moves, comprising two ultrasonic sensors; The ultrasonic sensors are respectively located at opposite positions of the U-shaped end of the robot; the two ultrasonic sensors operate in a self-receiving mode or a mutual receiving mode; the control unit is configured to start detecting and processing the obtained distribution of the ultrasonic intensity to obtain the silicon An abnormal state distribution of the sheet on the carrier; wherein the abnormal state includes a state of a silicon wafer protrusion, a diagonal piece, a lamination, and/or an empty piece; and an alarm unit connected to the control unit, The control unit controls the opening and closing of the alarm unit according to the abnormal state distribution.

Preferably, the apparatus further includes a rotating unit for driving the carrier to rotate relative to the robot and/or positioning, or to drive the robot to rotate and/or position relative to the carrier. .

Preferably, the image sensing unit is disposed on the inner surface of the robot or the end cap, and is positioned above the wafer set during operation.

It can be seen from the above technical solution that the image combination detecting method and device for distributing the silicon wafer in the bearing area of the semiconductor device provided by the present invention are completed in two stages, that is, after the wafer transfer sheet is completed and taken. Before, by setting an image sensing unit above the silicon wafer set and setting a photoelectric scanning unit or an ultrasonic scanning unit on the robot, the following four detection stages are performed: in the image acquisition mode of the first detection stage, the silicon tab is executed. An abnormal state limit position pre-scan command; by the photoelectric scanning/ultrasound scanning unit in the second detection stage operating in the self-receiving ranging mode, performing a cyclic scan instruction for all the wafers above the pre-scanning tab, the third detection Converting the phase to the mutual receiving mode, performing the silicon distribution state abnormal scan instruction, and converting the fourth detection phase into the self-receiving mode, performing a cyclic scan instruction for pre-scanning all the silicon wafers under the tab; thus, the present invention It can quickly and accurately diagnose whether there is any abnormal distribution of silicon wafer protrusion, oblique sheet, lamination and/or blank in the area of the carrier, and arrange multiple scanning detection points around the carrier to realize The multi-angle detection further improves the detection accuracy, and the damage of the silicon wafer and the device caused by the movement of the robot is well avoided. The experiment proves that the technical solution of the invention is simple to implement and the effect is good.

DRAWINGS

1 is a schematic view showing the position of a robot in the prior art during wafer transfer, wafer placement, and wafer taking.

2 is a schematic view showing the structure of a carrier end cover (Shutter) located above the silicon wafer group in the prior art.

3 is a view showing a structure in which an image sensing unit of a silicon wafer distribution state image detecting device in a semiconductor device carrying region is located above a silicon wafer group, and a structure in which the first and second photoelectric sensors are respectively located at a U-shaped end of the robot; schematic diagram

4 is a view showing an image sensing unit in a silicon wafer distribution state image detecting device in a semiconductor device carrying region according to an embodiment of the present invention, which is located on an end cover (automatic shutter) above the silicon wafer group, and first and second ultrasonic waves. The structure of the sensor is located at the U-shaped end of the manipulator

FIG. 5 is a schematic flow chart of a preferred embodiment of a method for detecting combined image state of a silicon wafer according to the present invention; FIG.

6 is a flow chart of overall control of image combination detection of silicon wafer distribution state according to an embodiment of the present invention;

FIG. 7 is a schematic diagram showing an image of a protruding abnormal state of a silicon wafer according to an embodiment of the present invention;

8 is a flow chart of command control of a preferred embodiment of the wafer abnormality detection of the present invention;

FIG. 9 is a schematic diagram showing the movement trajectory of the first and second photosensors in detecting the abnormal distribution state of the silicon wafer in the embodiment of the present invention;

FIG. 10 is a schematic view showing the change in the receiving time of the first and second photosensors at the relative positions of the U-shaped end of the robot according to the range of the occlusion according to the present invention;

FIG. 11 is a schematic diagram showing the relationship between the positions of the first and second photosensors/first and second ultrasonic sensors when the silicon wafer is in the silicon wafer drop limit position in the embodiment of the present invention;

FIG. 12 is a schematic diagram showing the calculation principle of the minimum safety distance between the U-shaped end of the manipulator and the center of the silicon wafer in the embodiment of the present invention;

FIG. 13 is a schematic diagram of a specific control flow of a preferred embodiment for determining whether an abnormal state of a slanting piece, a lamination, and/or an empty piece exists in an embodiment of the present invention;

FIG. 14 is a schematic diagram showing positional relationship parameters of a silicon wafer and a carrier according to an embodiment of the present invention;

[reference mark in the figure]:

Robot 1

Wafer group 2

Carrier 3

First photosensor 4

Second photosensor 5

First ultrasonic sensor 6

Second ultrasonic sensor 7

End cap 8

Image sensing unit 9

Summary of the invention

In order to make the content of the present invention clearer and easier to understand, the contents of the present invention will be further described below in conjunction with the accompanying drawings. Of course, the invention is not limited to the specific embodiment, and general replacements well known to those skilled in the art are also encompassed within the scope of the invention. In the following, the present invention has been described in detail with reference to the accompanying drawings.

Referring to FIG. 2, FIG. 3 and FIG. 4, FIG. 2 is a schematic structural view of a carrier end cover (Shutter) located above a silicon wafer set in the prior art; FIG. 3 is a diagram showing a silicon wafer distribution in a bearing area of a semiconductor device according to an embodiment of the present invention; The image sensing unit 9 in the state image detecting device is located on the robot 1 above the silicon wafer set 2, and the first and

second photosensors

4, 5/first and second ultrasonic sensors 6, 7 are respectively located at the U-shaped end of the robot. Schematic. 4 is a carrier end cover 8 of the image sensing unit 9 above the silicon wafer group 2, and the first and second photosensors 4 in the image distribution device for the silicon wafer distribution state of the semiconductor device carrying region in the embodiment of the present invention; 5/ The first and second ultrasonic sensors 6, 7 are respectively located at the opposite positions of the U-shaped end of the manipulator.

As shown in FIG. 3, the silicon wafer distribution state image detecting method of the semiconductor device carrying region provided by the present invention is disposed on the robot 1 above the silicon wafer group 2, and the image sensing unit 9 is disposed, and according to different In a technical solution, a photoelectric scanning unit (first combination scheme) or an ultrasonic scanning unit (second combination scheme) may be provided on the robot 1 located on the circumferential side of the wafer carrier 3. The photoelectric scanning unit includes first and

second photosensors

4, 5, and the ultrasonic scanning unit includes first and second Two ultrasonic sensors 6,7. The first and

second photosensors

4, 5 / the first and second ultrasonic sensors 6, 7 may be set to a self-receiving mode or a mutual reception mode as needed.

In the embodiment of the present invention, the whole detection process is divided into four stages: in the image acquisition mode of the first detection stage, the abnormal state limit position pre-scanning instruction of the silicon wafer is performed; and the photoelectricity in the second detection stage is performed. The scanning/ultrasonic scanning unit first operates in the self-receiving ranging mode, performs a cyclic scanning instruction of all the silicon chips above the pre-scanning tab, and the third detection phase is converted into a mutual receiving working mode, and an abnormal scanning instruction of the silicon distribution state is executed. And the fourth detection phase is further converted into the self-receiving operation mode, and a cyclic scan instruction for performing pre-scanning of all the silicon wafers under the tabs is performed; and a plurality of scan detection points are arranged around the carrier, thereby further improving the detection precision.

As shown in FIG. 4, the silicon wafer distribution state image detecting method of the semiconductor device carrying region provided by the present invention is disposed on the inner surface of the end cover 8 of the carrier 3 located above the silicon wafer group 2, and is provided with an image sensing unit 9, Moreover, according to different technical solutions, it is possible to select a photoelectric scanning unit (first combination scheme) or an ultrasonic scanning unit (second combination scheme) on the robot 1 located on the circumferential side of the wafer carrier 3. The photoelectric scanning unit includes first and

second photosensors

4, 5, and the ultrasonic scanning unit includes first and second ultrasonic sensors 6, 7. The first and

second photosensors

4, 5 and the first and second ultrasonic sensors 6, 7 may be set to a self-receiving mode or a mutual reception mode as needed. Similarly, in the image acquisition mode of the first detection stage, the abnormal state limit position pre-scanning instruction of the silicon wafer is performed; and the photoelectric scanning/ultrasound scanning unit in the second detection stage operates in the self-receiving ranging mode first. During the pre-scanning of the cyclic scan command of all the silicon wafers above the tab, the third detection phase is converted into the mutual reception operation mode, the silicon distribution state abnormal scan instruction is executed, and the fourth detection phase is converted into the self-reception operation mode, and execution is performed. Cyclic scanning instructions for pre-scanning all of the silicon wafers under the tabs; and multiple scan detection points are placed around the carrier to further improve The detection accuracy.

Each of the above devices includes a control unit (not shown) for initiating detection and processing to obtain image signal conditions, photoelectric intensity, and ultrasonic signal strength results acquired by the image sensing unit 9, and determining the silicon wafer by using the results. The abnormal state distribution of the group 2 on the carrier 3; wherein the abnormal state includes the state of the silicon bump, the diagonal piece, the lamination and/or the empty piece; and the control unit may also be connected to the alarm unit, and the control unit may The opening and closing of the alarm unit is controlled according to the abnormal state distribution.

Referring to FIG. 5 and FIG. 6, FIG. 6 is a schematic flow chart of a preferred embodiment of a method for detecting image distribution of a silicon wafer distribution state in a bearing region of a semiconductor device according to the present invention. FIG. 6 is a flow chart of overall control of image combination detection of a silicon wafer distribution state in a semiconductor device carrying area according to an embodiment of the present invention. As shown, the method includes the following steps:

Step S1: The image sensing unit 9 is disposed above the silicon wafer group 2, and the center coordinate of the ideally placed silicon wafer and the threshold value of the actual placement region from the center coordinate are set; the image sensing unit 9 is activated to take a wafer placement state image. And using the image feature recognition algorithm to determine whether the wafer placement in the silicon group 2 has exceeded the deviation threshold; if so, step S5 is performed, otherwise, step S2 is performed;

Step S2: setting the operation modes of the first and

second photosensors

4, 5 / the first and second ultrasonic sensors 6, 7 to the self-receiving mode, and the first and

second photosensors

4, 5 / first and The ultrasonic sensors 6, 7 are positioned corresponding to the vertical starting point of the first placement of the silicon wafer of the carrier 3 and the image protruding point detected by the step S1 as the horizontal starting point position;

Step S3: according to the first and / or

second photosensors

4, 5, or the first and / or second ultrasonic sensors 6, 7, respectively, the time difference between the transmission and reception of optical signals in the vertical downward direction of the silicon wafer stack a predetermined judgment rule for judging that the silicon wafer has a vertical coordinate that protrudes from an abnormal state of the specified position;

Step S4: The robot 1 advances along the center of the carrying area by a predetermined horizontal step distance to determine whether the position is a horizontal end point position; if yes, step S5 is performed; otherwise, step S3 is performed;

Step S5: setting the two

photosensors

4, 5/ultrasonic sensors 6, 7 to the mutual receiving mode, and the robot 1 executes all the wafer distribution state abnormal scanning commands from the vertical starting position to the vertical ending position of the horizontal end point position, according to the two The

photoelectric sensor

4, 5 / ultrasonic sensor 6, 7 feedback value of mutual feedback and reception in the scan detection area of the distribution of optical signal intensity, to determine whether there are abnormal states of the oblique, laminated and / or empty;

Step S6: setting the two

photosensors

4, 5 / ultrasonic sensors 6, 7 in a self-receiving mode, according to the first and / or

second photosensors

4, 5, or the first and / or second ultrasonic sensors 6, 7. The time difference between each of the optical signals emitted and received in the vertical upward direction of the stacked silicon wafer and a predetermined determination rule, and determining that the silicon wafer has a vertical coordinate that protrudes from the abnormal state of the specified position;

Step S7: The robot 1 advances in a direction opposite to the center of the carrying area by a predetermined horizontal step distance, and determines whether the position is the horizontal starting point position of the image protruding point detected in step S1; if yes, ends; otherwise, step S6 is performed. .

That is to say, the present invention completes the entire detection process by the following four detection sub-stages after completion of the transfer of the wafer and before taking the film (hereinafter the first and/or

second photosensors

4, 5 are located in the robot 1). Taking the U-shaped end as an example, the first and/or second ultrasonic sensors 6, 7 operate in substantially the same way as the first and/or second photosensors 4, 5):

The first detection phase:

First, the center coordinate of the ideal placement of the silicon wafer and the deviation threshold of the actual placement area from the center coordinate are set; referring to FIG. 7, FIG. 7 is an image showing the abnormal state of the silicon wafer in the embodiment of the present invention. intention. As shown in the figure, assume that the theoretical center of the theoretical silicon wafer is A (xa, ya) and the radius is Ra, that is, the wafer image is at the center of the normal silicon wafer position (blank); if the actual silicon image is in the dark gray region, the circumferential region The center is the same as the center of the normal wafer position (blank) area, and the radius (the distance of the edge from the center point) is different as Rb. Since Rb does not exceed the deviation threshold, it is within the acceptable deviation range; if the actual silicon image is light gray The area, the center of the circumferential area is the same as the center of the normal silicon wafer position (blank) area, and the radius is different from Rc. If the deviation threshold is exceeded, it is within the unacceptable deviation range.

In some embodiments of the present invention, the actual silicon wafer center point C(xc, yc) can be obtained by an image acquisition and recognition algorithm;

That is, the distance between the center point of the actual silicon wafer and the center point of the theoretical silicon wafer, that is, the degree of eccentricity, can be calculated, and whether the silicon wafer has a prominent problem can be calculated. The image recognition method selects a point at which the silicon wafer and the support mechanism are connected as a feature recognition point, and uses three points not on the same line to determine the center position of one circle, and selects three points from the total feature point by using the group method. For a set of C _n ³ arrangement, the center coordinate position is calculated, and then the center coordinates of all groups are averaged to obtain C(xc, yc).

According to the above-described judging principle, the wafer abnormality condition is obtained by the detection result image of the image sensing unit 9. Please refer to FIG. 8. FIG. 8 is a flow chart of command control of a preferred embodiment of the silicon wafer protruding abnormal state detection according to the present invention. After the silicon wafer protrudes abnormal state image detection, after the silicon wafer protrusion abnormality occurs, the positioning step of the silicon wafer protruding abnormal condition and the execution of all the silicon wafer distribution state abnormal scanning instruction, that is, steps S2, S3, S4, S5, and S6, will be required. And S7.

The second detection phase:

In steps S2, S3 and S4 of the present embodiment, for the case where the first and

second photosensors

4, 5 are set to the self-receiving mode, they can measure the obstacle distance on the blocked beam propagation path by the time difference between transmission and reception. The distance of the photoelectric sensor. In the detection phase, the vertical starting position of the robot 1 carrying the first and

second photosensor groups

4, 5 is first positioned above the first wafer position where the carrier 3 is placed on the wafer set 2, horizontally starting The position of the image sticking point detected in step S1 is positioned as a horizontal starting point position. The emitters of the first and

second photosensor groups

4, 5 operating in the self-receiving mode are emitted downwardly perpendicular to the wafer set 2 when the abnormal state limit position pre-scan command of the silicon tab is performed. Further, according to the time difference between the first and/or

second photosensors

4, 5 for transmitting and receiving the optical signals in the vertical direction of the stacked silicon wafer and the predetermined determination rule, it is judged that the silicon wafer has the vertical coordinate which protrudes from the abnormal state of the prescribed position.

In steps S2, S3 and S4 of the present embodiment, for the case where the first and second ultrasonic sensors 6, 7 are set to the self-receiving mode, they are also measurable by obstructing the obstacle propagation path by the time difference between self-transmitting and receiving. The distance from the ultrasonic sensor group, that is, the distance measurement mode. The propagation speed of the ultrasonic wave in the air is 340 m/s. According to the time t recorded by the timer, the distance (s) of the emission point from the obstacle can be calculated, that is, s=340t/2.

1. Ultrasonic ranging error analysis

According to the ultrasonic ranging formula L=C×T, it is known that the error of the ranging is caused by the propagation velocity error of the ultrasonic wave and the time error of the measurement distance propagation.

2, time error

When the ranging error is required to be less than 1 mm, it is assumed that the ultrasonic velocity C = 344 m/s (20 ° C room temperature) is known, and the propagation error of the sound velocity is ignored. The ranging error sΔt<(0.001/344)≈0.000002907s is 2.907μs. The difference in propagation time of the measured distance under the premise that the propagation speed of the ultrasonic wave is accurate As long as the accuracy reaches microseconds, the error of the ranging error is less than 1mm.

3, ultrasonic propagation speed error

The propagation speed of ultrasonic waves is affected by the density of air. The higher the density of air, the faster the propagation speed of ultrasonic waves, and the density of air is closely related to temperature. When the ultrasonic ranging accuracy is required to be 1 mm, the ambient temperature of the ultrasonic wave propagation must be taken into consideration. For example, the ultrasonic velocity is 332 m/s at a temperature of 0 ° C, 350 m/s at 30 ° C, and the ultrasonic velocity change due to a temperature change is 18 m/s. If the ultrasonic wave is measured at a sound velocity of 0 ° C in an environment of 30 ° C, the measurement error caused by the 100 m distance will reach 5 m, and the measurement 1 m error will reach 5 cm. In this design, the ultrasonic propagation speed is corrected by real-time sampling of the temperature feedback value of the working environment of the ultrasonic ranging probe, and the measurement error is controlled within 1 mm.

In the following description of the steps in the embodiment, the first and

second photosensors

4, 5 are taken as an example for detailed description. The first and second ultrasonic sensors 6 and 7 have the same principle, and are not described herein again.

After the step S3 is completed, the position coordinates of the most convex silicon wafer in the silicon wafer group 2 are obtained, and the convex state detection of the silicon wafer above the position coordinates of the most convex silicon wafer is continued (ie, step S4). Specifically, the robot 1 advances a predetermined horizontal step distance along the center of the carrying area, and continues to perform step S3 until it is determined whether the silicon wafer in the position of the most protruding silicon wafer in the immediately adjacent silicon wafer group 2 has a convex state. After that, step S5 is performed.

Please refer to FIG. 9. FIG. 9 is a schematic diagram of a movement trajectory of the first and second photosensors in detecting a prominent abnormal distribution state of the silicon wafer according to an embodiment of the present invention.

The third detection phase:

In the third detection stage in the embodiment of the present invention, two

photosensors

4, 5 need to be set to each other. In the receiving mode, the robot 1 executes all the wafer distribution state abnormal scanning commands from the vertical starting position to the vertical ending position after the execution of the step S4, and scans according to the feedback values of the two

photosensors

4 and 5 mutually transmitting and receiving. The distribution state of the optical signal intensity in the detection area is determined to determine whether there is an abnormal state of the oblique piece, the lamination, and/or the empty piece.

In this embodiment, step S5 specifically includes the following steps:

Step S51: obtaining a motion scanning area for judging the oblique piece, the lamination piece and the empty piece according to the thickness of the silicon wafer and the separation distance of the adjacent silicon wafers;

Step S52: The robot 1 is positioned at a vertical motion starting point position; in this embodiment, the vertical motion starting point position is a vertical coordinate position of the first silicon piece in the carrier 3, and the horizontal coordinate may be the coordinate after the step S4 is completed. That is, the horizontal coordinate is the horizontal end point position;

Step S54: The robot 1 sequentially drops the distance of a silicon wafer to determine whether the position is a vertical end point position; if so, end; otherwise, step S53;

Specifically, the first and

second photosensors

4, 5 located at the relative positions of the U-shaped end of the robot are set to the mutual receiving mode, and the detecting operation principle of the step S5 is shown in FIG. As shown, the feedback value reception time of the first and

second photosensors

4, 5 varies in intensity with the range of occlusion. In the case of normal detection, in order to obtain scan data of the silicon wafer at a certain position on the load-bearing structure, the judgment of the obstacle-free object is determined by the change of the intensity of the photoelectric sensor, that is, the center value of the wafer scanning teaching is Benchmark, if the light intensity return value of the receiving end of the photoelectric sensor is less than the specified threshold α, it is considered that there is object occlusion in the corresponding area, and the return state value is 1, indicating that the silicon wafer at the corresponding position of the carrier 3 is in a protruding abnormal state; if the photoelectric sensor Light intensity return value at the receiving end If it is greater than or equal to the specified threshold α, it is considered that there is no object in the corresponding area, and the return status value is 0, which means that the silicon wafer at the corresponding position of the carrier 3 is in a normal state.

As shown in FIG. 10, the detection time points t1, t2, t3, t4 appearing on the abscissa are related to the motion scanning speed of the robot 1, and therefore, the state of the silicon wafer can be determined according to the starting point and range of the time detection result change. At the same time, it can calculate the degree of protrusion beyond the normal range, and obtain the diagnosis result of whether the position of each wafer can be safely processed or unloaded.

Before the start of the detection process, the control parameters of the robot 1 can be taught in advance. These control parameters can control the preset direction and position of the robot 1 and also set the scanning detection trajectories of the two pairs of photoelectric sensors or ultrasonic sensors. The initialization parameter includes parameters of the first and

second photosensors

4, 5 horizontal starting point position and end point position, the distance between the silicon wafers, and the horizontal step spacing of the robot.

The starting position of each scan detection of the robot 1 scan detection track is determined by the horizontal start point position and the up/down vertical start point position, and the up/down vertical start point position is two positions, and the upper vertical start point position corresponds to silicon. The position of the top wafer of the wafer group 2 is placed, and the position of the lower vertical starting point corresponds to the position where the underlying silicon wafer of the silicon wafer group 2 is placed.

In the detection process, if it starts from the upper vertical starting point position, the next detecting position is to sequentially lower the spacing distance of an adjacent silicon wafer until the vertical starting point position; similarly, if it is from the lower vertical starting point When the position starts, the next detection position is to sequentially increase the separation distance of an adjacent silicon wafer until the vertical starting point position. In the present embodiment, since the image sensing unit 9 is located above the silicon wafer set 2, the scanning of the step S5 is performed by the first silicon wafer on the top of the carrier 3 to the last wafer of the top.

The motion detection area for the horizontal detection scanning direction is determined by the structural parameters of the carrier 3 and silicon. The horizontal starting position determined by the size parameter of the slice is related to the detection result obtained in step S3.

Assuming X is the distance between the transmitting end and the receiving end of the first and

second photosensors

4, 5 on the robot 1, then the value of X needs to ensure that the robot 1 can normally scan the specified size wafer during the movement without Interference with the silicon wafer.

Please refer to FIG. 11. FIG. 11 is a schematic structural diagram showing the positional relationship between the first and second photosensors/first and second ultrasonic sensors when the silicon wafer is in the silicon wafer drop limit position according to the embodiment of the present invention. As shown in the figure, assuming that the center of gravity of the wafer in the figure is located at the edge of the support structure of the carrier 3 (offset from the normal position Y), the maximum displacement position of the silicon wafer does not slip off the support structure, and the relative absolute horizontal position of the silicon wafer is set to γ. The value of γ is determined by the structural design, which has the following relationship:

Tan(γ)=s/Y, γ=arctan(s/Y), s is the separation distance between two adjacent silicon wafers, that is, two adjacent silicon wafers when the silicon wafer group 2 is horizontally placed on the carrier 3. The distance of the center in the vertical direction; then

δ>0, which is the safety margin setting value, and X is the distance between the first and second photosensors 4, 5 (or the first and second ultrasonic sensors 6, 7).

Please refer to FIG. 12. FIG. 12 is a schematic diagram showing the calculation principle of the minimum safety distance between the U-shaped end of the robot and the center of the silicon wafer according to an embodiment of the present invention. As shown in the figure, the scan detection start position is set to be Z from the center distance of the carrier 3, and the time change value of the horizontal detection scan is set to b(t), and b(t) represents two photoelectrics on the robot 1. The real-time distance between the center line of the sensor 4 and the center of the support structure, then b(0)=Z at the horizontal scanning detection start position; in addition, in order to consider the safety margin, b(t)=Y+δ is the formal acquisition of silicon. The distance of the sheet distribution state from the center of the structure of the carrier 3;

X is the distance between the first and

second photosensors

4, 5/first and second ultrasonic sensors 6, 7 on the robot 1;

Y is the radius of the carrier 3, that is, the length from the center point of the carrier 3 to the edge thereof;

r is the radius of the silicon wafer in the silicon wafer group 2, that is, the length from the center of the silicon wafer to the edge thereof;

s is the separation distance between two adjacent silicon wafers, that is, the distance between the centers of two adjacent silicon wafers in the vertical direction when the silicon wafer group 2 is horizontally placed on the carrier 3;

γ is the tilt angle of the wafer set relative to the absolute horizontal position, and it is clear to those skilled in the art that the thickness of the general-purpose silicon wafer is usually 0.7 mm, relative to a silicon wafer having a diameter of 300 mm or 200 mm, that is, a radius of 150 mm or 100 mm. The ratio of the thickness 2 of the silicon wafer 2 is less than 1/100. Therefore, when calculating the tilt angle of the silicon wafer, the thickness d of the silicon wafer can be approximately 0. In this case, the relationship of the tilt angle can be calculated as follows:

Tan(γ)=s/Y,

γ(0)=arctan(s/Y), that is, the value of γ(0) is determined by structural design

Referring to FIG. 12, when the center of gravity of the silicon wafer is located at the edge of the support structure, the projection of the tilted silicon wafer on the absolute horizontal plane is:

If Z is the limit scan start position, that is, the center of the robot 1 is at the center distance from the carrier 3 at that position, that is, at the horizontal scanning detection start position, b(0)=Z, then the safety margin is considered;

δ>0, which is the safety margin setting value, that is, the safety distance that the robot 1 does not interfere with the silicon wafer in the vertical direction at this time, and the value is also the same as the above X, r and the wafer center and the robot 1 Whether the center of the U-port is affected by the same horizontal line. Therefore, when detecting, it is necessary to position the center line and the silicon between the first and second photosensors 4 and 5 on the U-shaped port that are mutually transmitting and receiving. On a flat surface. Moreover, the distance between the connection between the first and second photosensors 4, 5 on the robot 1 and the center of the silicon wafer 2 in the same plane needs to be greater than:

That is to say, when the limit scan does not detect the silicon wafer abnormality, that is, when the silicon wafer is tilted, the robot 1 moves in the horizontal direction as follows, and the movement in the vertical direction is still not generated with the inclined silicon wafer. put one's oar in;

After the horizontal scanning start point setting is completed, it is also necessary to set the distance for the robot 1 to move toward the center of the carrier 3 every time c(t), where t=0, 1, 2, 3...; the robot 1 is horizontal The horizontal stepping distance of each direction of movement may be the same or different, for example, it may be gradually reduced.

If a(t) is an intermediate length variable, the distance that robot 1 can safely move at a time, a(0)=0; b(t) is the intermediate length variable, that is, the real-time distance between the center of the robot 1 and the center of the silicon wafer. b(0)=Z; h(t) is an intermediate length variable used to calculate the tilt angle of the silicon wafer, h(0)=Y; then,

b(t)=b(t-1)–a(t)

Referring to FIG. 13, FIG. 13 is a schematic diagram showing a specific control flow of a preferred embodiment for determining whether there is an abnormal state of a slanting piece, a lamination, and/or an empty piece in the embodiment of the present invention. In this embodiment, the abnormal state detection of the oblique pieces, the laminations, and/or the empty sheets is sequentially performed.

Specifically, please refer to FIG. 14, which is a schematic diagram of positional relationship parameters between a silicon wafer and a carrier according to an embodiment of the present invention. If the silicon wafer thickness value d is set, the teaching reference position is d/2, the interval between adjacent silicon wafers is s, and the interval thickness of the carrier 3 is t, according to the different scanning regions, the receiving end of the photoelectric sensing unit 4 When the return value is 1/0, the distribution state of the silicon wafer is as shown in Table 1 below.

Table 1

As can be seen from the above Table 1, it can be judged whether or not a slanting piece, a lamination or a chipless phenomenon occurs in the corresponding area according to the preset detection area and the optical signal shielding width in the area, that is, the detected return value. For the case of the oblique slice, in the range of the motion scanning area [2*(d+d*1/3), Sd*1/3], if the width of the shadowed area in the detection result >=d, then it can be concluded. A slanting phenomenon occurs at the corresponding position. If the width of the occlusion area is <0.1d in the detection result, it can be concluded that there is no slanting phenomenon at the corresponding position. If the width of the occlusion area in the detection result is not in the above two cases Range, then the control unit can send a reminder message to the alarm unit or issue information to perform the detection again until all the wafer placement position scan results are obtained. If there is an abnormal position, an alarm prompt for the specified position abnormality is given, waiting for manual disposal or according to regulations. Dispose of.

The fourth detection phase:

Please note that after performing step S5, the vertical coordinate of the robot 1 is the vertical coordinate of the last silicon wafer in the silicon wafer group 2 carried by the carrier 3, and the horizontal coordinate is the horizontal end point position; that is, the above steps have been completed. Steps S3, S4 and S5, and then it is necessary to complete the detection of the convex state of the silicon wafer below the position coordinates of the most protruding silicon wafer (ie, step S6); that is, two

photosensors

4, 5 Provided in a self-receiving mode, according to the first and/or

second photosensors

4, 5, the time difference of each of the optical signals transmitted and received in the vertical upward direction of the silicon wafer stacking and a predetermined judgment rule, determining that the silicon wafer has a prominent predetermined position abnormality The vertical coordinate of the state.

Moreover, since the one-side scanning for performing the abnormality of the protruding of the silicon wafer cannot completely diagnose the distribution state of the abnormality of the silicon wafer in the bearing area, in some embodiments of the present invention, it can be set on the carrier 3 or the robot 1 a rotating unit that enables the robot 1 to perform relative rotational movement about the carrier 3, and a plurality of rotation detecting stop positions are disposed around the sides of the entire carrier 3, and step S2 is performed once for each detecting position. The operation of S3, S4, S5, S6 and S7 obtains a corresponding set of detection results; finally, the multiple sets of detection results are compared and operated to obtain the abnormal state distribution of the final silicon wafer tab, that is, the silicon wafer can be realized more Angle distribution state detection.

According to the support structure of the carrier 3, a plurality of position points may be evenly distributed or unevenly distributed; for example, in order to avoid the support column of the carrier 3, it may be 10° or 20° from the left and right of the support column. Reset the point detection.

For the case where the rotation angles of two adjacent ones of the plurality of position points are the same, the selection is set as follows

A. When the remainder of (360 ° / set rotation angle) = 0:

Cumulative detection position number = 360 ° / set rotation angle

Actual rotation angle = set rotation angle

B. When the remainder of (360°/set rotation angle) ≠0:

Actual rotation angle = 360° / number of cumulative detection positions

Of course, if the detected position coordinate value and bearing generated by the rotation starting point and the set rotation angle If the coordinate position of the support point of the device 3 conflicts, the starting point and the rotation angle value need to be reset.

Then, the position on the circumference generated by the collision-free starting point and the set rotation angle can be obtained to obtain the state of the distribution of the silicon wafer in the entire bearing area, and each detection position acquires a set of distribution state values, and then The state results of the distribution positions of all detected positions are summed. There are two results:

A. Normal, the operation after placing the silicon wafer or the film taking operation after scanning can be performed.

B. Anomaly, the abnormal position and result are reported for the user to dispose, and the user operation option is provided according to the abnormal result.

In addition, referring to FIG. 7, after finally obtaining the detection scan result of the oblique piece, the lamination and/or the empty piece, the process judging step can be performed, and the specific process steps of the step are presented in FIG. This will not be repeated here.

Although the invention has been disclosed above in the preferred embodiments, the above embodiments are not intended to limit the invention. For those skilled in the art, many possible variations and modifications may be made to the technical solutions of the present invention, or modified to equivalent changes, etc., without departing from the scope of the present invention. Effective embodiment.

Claims

A silicon wafer distribution state image combination detecting method, wherein an image sensing unit is disposed above a silicon wafer group, and first and second photosensors/first and second ultrasonic sensors are disposed on a circumference of the carrier a side robot and moving with the robot; the first and second photosensors/first and second ultrasonic sensors are respectively located at opposite ends of the U-shaped end of the robot; wherein the method comprises the following step:

Step S1: setting a center coordinate of the ideally placed silicon wafer and a deviation threshold of the actual placement area from the center coordinate; starting the image sensing unit to take a picture of the placement state of the silicon wafer, and using the image feature recognition algorithm to determine the placement of the silicon wafer in the silicon wafer group Whether there is a case where the deviation threshold is exceeded; if yes, step S5 is performed, otherwise, step S2 is performed;

Step S2: setting the operating modes of the first and second photosensors/first and second ultrasonic sensors to a self-receiving mode, and the first and second photosensors/first and second ultrasonic sensor positioning corresponding to the carrier a vertical starting point at which the silicon wafer is placed and an image protruding point detected in step S1 as a horizontal starting point position;

Step S3: judging according to the first and/or second photosensors, or the first and/or second ultrasonic sensors, respectively, the time difference of transmitting and receiving the optical signals in the vertical downward direction of the silicon wafer stack and the predetermined judgment rule The silicon wafer has a vertical coordinate that highlights an abnormal state of the specified position;

Step S4: the robot advances a predetermined horizontal step distance along the center of the carrying area to determine whether the position is a horizontal end point position; if yes, step S5 is performed; otherwise, step S3 is performed;

Step S5: setting two photosensors/ultrasonic sensors in an inter-acceptance mode, the robot performs an abnormal scan command of all silicon distribution states from a vertical start position to a vertical end position of the horizontal end point position, according to two photoelectric sensors/ultrasounds The feedback value of the mutual feedback and reception between the sensors is in the distribution state of the optical signal intensity in the scanning detection area, and it is determined whether there is an abnormal state of the oblique piece, the lamination and/or the empty piece;

Step S6: setting two photosensors/ultrasonic sensors into a self-receiving mode, according to the a first and/or second photosensor, or a first and/or second ultrasonic sensor, each having a time difference of transmitting and receiving an optical signal in a vertical upward direction of the silicon wafer stack and a predetermined determination rule, determining that the silicon wafer has a protruding prescribed position The vertical coordinate of the abnormal state;

Step S7: the robot advances in a direction opposite to the center of the carrying area by a predetermined horizontal step distance, and determines whether the position is a horizontal starting point position of the image protruding point detected in step S1; if yes, ends; otherwise Go to step S6.
The detecting method according to claim 1, wherein the step S5 specifically comprises the following steps:

Step S51: obtaining a motion scanning area for judging the oblique piece, the lamination piece and the empty piece according to the thickness of the silicon wafer, the separation distance of the adjacent silicon wafers, and the thickness of the carrier;

Step S52: the robot is positioned at a horizontal motion starting point position and a vertical ending point position;

Step S53: sequentially determining whether the corresponding silicon wafer placement position has a slanting piece according to a preset detection area in which the two photoelectric sensors and/or the ultrasonic scanning unit mutually transmit and receive optical signals and a light signal shielding width in the area. The abnormal state of the lamination and/or the blank; if yes, step S55 is performed; otherwise, step S54 is directly performed;

Step S54: the robot sequentially descends the distance of a silicon wafer to determine whether the position is a vertical end point position; if so, end; otherwise, step S53;

Step S55: The abnormal state information of the oblique piece, the lamination and/or the empty piece is issued at the corresponding position, and step S54 is performed.
The detecting method according to claim 1 or 2, wherein the carrier or the robot comprises a rotating unit, and the rotating unit causes the robot to rotate relative to the carrier, and There are N rotation detection stop positions on the side of the carrier, and the steps S1 to S7 are performed once at each detection position to obtain a corresponding set of detection results; finally, the N sets of detection results are ANDed to obtain the final silicon. An abnormal state distribution of the tabs, where N is a positive integer greater than or equal to 2.
The detecting method according to claim 3, wherein the rotation angles of the two adjacent ones of the N positions are the same, and the selection is set as follows:

A. When the remainder of (360 ° / set rotation angle) = 0:

Cumulative detection position number = 360 ° / set rotation angle

Actual rotation angle = set rotation angle

B. When the remainder of (360°/set rotation angle) ≠0:

The total number of detected positions = (360 ° / set rotation angle) rounded (after rounding off the decimal point) +1

Actual rotation angle = 360° / number of cumulative detection positions

If the detected position coordinate value generated by the rotation start point and the set rotation angle conflicts with the coordinate position of the carrier support point, the start point and the rotation angle value need to be reset.
The detecting method according to claim 2, wherein in the steps S4 and S6, the horizontal step distance of the robot moves in the horizontal direction is equal, gradually becomes larger, and/or gradually decreases; and the level The starting position is related to the position at which the wafer is in the drop limit position, which is related to the support structure parameters of the carrier.
An apparatus for detecting a distributed state image of a silicon wafer according to any one of claims 1 to 5, characterized in that it comprises:

An image sensing unit disposed above the silicon wafer set for overhead view of an image stacked in a state in which the silicon wafer is placed in the silicon wafer group;

a photoelectric scanning unit disposed on a robot hand on a circumferential side of the carrier and moving in a horizontal and/or vertical preset direction and performing scanning detection as the robot moves, comprising two photoelectric sensors; The photoelectric sensors are respectively located at opposite positions of the U-shaped end of the robot, and the two photoelectric sensors operate in a self-receiving mode or a mutual receiving mode;

a control unit, configured to initiate detection and process the obtained photoelectric intensity and distribution result, to obtain an abnormal state distribution of the silicon wafer on the carrier; wherein the abnormal state includes a silicon wafer protrusion, a diagonal piece, and a stack The state of the slice and/or the blank;

An alarm unit is connected to the control unit, and the control unit controls opening and closing of the alarm unit according to an abnormal state distribution.
The detecting device according to claim 6, further comprising a rotating unit for driving said carrier to rotate and/or position relative to said robot, or to drive said The movement of the robot relative to the carrier for rotation and/or positioning.
The detecting device according to claim 6 or 7, wherein the image sensing unit is disposed on an inner surface of the robot or the end cap, and is positioned above the wafer group during operation.
An apparatus for detecting a distributed state image of a silicon wafer according to any one of claims 1 to 5, characterized in that it comprises:

An image sensing unit disposed above the silicon wafer set for overhead view of an image stacked in a state in which the silicon wafer is placed in the silicon wafer group;

An ultrasonic scanning unit disposed on a robot hand on a circumferential side of the carrier and moving in a horizontal and/or vertical preset direction and performing scanning detection as the robot moves, comprising two ultrasonic sensors; The ultrasonic sensors are respectively located at opposite positions of the U-shaped end of the robot; the two ultrasonic sensors operate in a self-receiving mode or a mutual receiving mode;

a control unit, configured to start detecting and processing the obtained distribution result of the ultrasonic intensity, to obtain an abnormal state distribution of the silicon wafer on the carrier; wherein the abnormal state includes a silicon wafer protrusion, a diagonal piece, and a stack The state of the slice and/or the blank;

An alarm unit is connected to the control unit, and the control unit controls opening and closing of the alarm unit according to an abnormal state distribution.
The detecting device according to claim 9, further comprising a rotating unit for driving said carrier to perform a rotation and/or positioning movement with respect to said robot, or driving said robot with respect to said bearing The motion of the rotation and / or positioning.
The detecting device according to claim 9 or 10, wherein the image sensing unit is disposed on an inner surface of the robot or the end cap, and is positioned above the wafer group during operation.