Device for automatically scanning and detecting wafer placement position

Abstract

The utility model discloses a device for automatically scanning and detecting the placement position of a wafer. The device comprises a scanner, a driving device connected with the scanner, a wafer anti-protrusion detection sensor and a control system, the wafer anti-protrusion detection sensor is used for detecting whether the wafer protrudes out of the wafer box or not; the scanner can move back and forth under the action of the driving device to scan the inside of the wafer box; and the control system is electrically connected with the scanner and the wafer anti-protrusion detection sensor and is used for receiving detection information of the scanner and the wafer anti-protrusion detection sensor and judging whether the placement position of the wafer in the wafer box is accurate or not according to the detection information. According to the device provided by the invention, whether the wafer in the wafer box is obliquely inserted or protrudes out of the wafer box can be automatically detected, a detection result can be fed back to a machine table in time, and the machine table judges whether normal operation can be carried out according to the result; and damage to a machine and yield loss caused by malfunction due to the fact that oblique insertion of the wafer cannot be found in time are avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of semiconductor production, and particularly relates to a device for automatically scanning and detecting the placement position of a wafer. Background Art

[0002] In the prior art, the loadPort (wafer loading device) of a wafer machine does not have the function of detecting whether the placement position of a wafer is accurate. Before placing the wafer cassette, it is only possible to manually check whether the position of the wafer in the wafer cassette is accurate and whether there is any skew insertion. Limited by the limitations of humans themselves, sometimes the skew insertion of the wafer cannot be detected in time, resulting in the mechanical arm hitting the wafer when picking and placing the wafer, causing damage to the machine and loss of yield. Content of the Utility Model

[0003] The purpose of the utility model is to provide a device for automatically scanning and detecting the placement position of a wafer to solve the deficiencies of the prior art.

[0004] The purpose of the utility model is achieved by the following technical solutions:

[0005] A device for automatically scanning and detecting the placement position of a wafer, which is used to detect whether the placement position of the wafer in the wafer cassette is accurate. The wafer cassette has multiple layers of wafer placement slots. The device for automatically scanning and detecting the placement position of the wafer includes a scanner, a driving device connected to the scanner, a wafer anti-protrusion detection sensor, and a control system;

[0006] The wafer anti-protrusion detection sensor is used to detect whether the wafer protrudes outside the wafer cassette;

[0007] The scanner can reciprocate under the action of the driving device to scan the inside of the wafer cassette;

[0008] The control system is electrically connected to the scanner and the wafer anti-protrusion detection sensor, and is used to receive the detection information of the scanner and the wafer anti-protrusion detection sensor, and judge whether the placement position of the wafer in the wafer cassette is accurate according to the detection information.

[0009] Preferably, the device provided in this application further includes a protective barrier, and the protective barrier and the wafer cassette are respectively located on opposite sides of the scanner.

[0010] Preferably, the protective barrier is provided with a height adjustment device.

[0011] Preferably, the device provided in this application further includes a start button electrically connected to the control system, and the start button is used to control the start of the entire device.

[0012] Preferably, the control system is also electrically connected to the driving device and the height adjustment device of the protective barrier.

[0013] Preferably, the device provided by the present application further includes a signal indicator electrically connected to the control system;

[0014] The signal indicator includes an "enable light" and a three-color signal light;

[0015] The three-color signal light includes red, green, and yellow lights. Among them, the red signal light is used to indicate that the machine is in an abnormal state, the green signal light is used to indicate that the machine is in a normal operating state, and the yellow signal light is used to indicate that the machine is in a state of waiting for materials.

[0016] Preferably, the scanner is located at the rear side of the wafer cassette, and the wafer anti-protrusion detection sensor is located at the front side of the wafer cassette.

[0017] Preferably, the device provided by the present application further includes a linear slide rail, and the driving device can move along the linear slide rail.

[0018] Preferably, the device provided by the present application further includes a work platform for placing the wafer cassette, and the linear slide rail is located below the work platform;

[0019] The work platform is provided with a first installation groove, a second installation groove, and a third installation groove for installing the wafer anti-protrusion detection sensor, the protective barrier, and the scanner respectively. A hole for the driving device to move is also provided on the work platform below the third installation groove.

[0020] Preferably, the work platform is further provided with a stopper for positioning the wafer cassette.

[0021] The device provided by the present application can automatically detect whether the wafers in the wafer cassette are inserted obliquely or protrude outside the wafer cassette, and can timely feedback the detection result to the machine. The machine judges whether it can operate normally based on this result; it avoids damage to the machine and loss of yield caused by misoperation due to failure to detect the oblique insertion of the wafers in time. Description of the Drawings

[0022] Figure 1 is a three-dimensional structural schematic diagram of the device for automatically scanning and detecting the placement position of wafers provided by the present application;

[0023] Figure 2 is a side view structural schematic diagram of the device for automatically scanning and detecting the placement position of wafers provided by the present application;

[0024] Figure 3 is a top view structural schematic diagram of the device for automatically scanning and detecting the placement position of wafers provided by the present application;

[0025] Figure 4 is the work flow chart of the present application;

[0026] Among them, 1 - control system; 2 - start button; 3 - flexible cable; 4 - linear slide rail; 5 - drive device; 6 - scanner; 7 - protective barrier; 8 - wafer anti - protrusion detection sensor; 9 - wafer cassette; 10 - stop block; 11 - working platform; 12 - enable light; 13 - three - color signal light. Specific embodiments

[0027] The device for automatically scanning and detecting the placement position of wafers provided by this application, as Figures 1 to 3 shown, is used to detect whether the placement position of wafers in the wafer cassette is accurate. The wafer cassette has multiple layers of wafer placement slots. The device for automatically scanning and detecting the placement position of wafers includes a scanner (Mapper) 6, a drive device 5 connected to the scanner, a wafer anti - protrusion detection sensor 8, and a control system 1.

[0028] Preferably, the scanner 6 and the wafer anti - protrusion detection sensor 8 are respectively located on opposite sides of the wafer cassette 9 so that their operations do not affect each other. As Figure 1 shown, the scanner is located at the rear side of the wafer cassette 9, and the wafer anti - protrusion detection sensor is located at the front side of the wafer cassette. Since the front end of the wafer cassette is completely open, the wafer may protrude forward out of the wafer cassette. Therefore, the wafer anti - protrusion detection sensor is provided on the front side of the wafer cassette, and the scanner is provided on the rear side of the wafer cassette.

[0029] The wafer anti - protrusion detection sensor 8 is used to detect whether the wafer protrudes out of the wafer cassette. The wafer anti - protrusion detection sensor 8 can be a laser sensor, including a transmitting end and a receiving end, which are respectively arranged closely on the upper and lower sides of the front end of the wafer cassette. When the wafer protrudes out of the wafer cassette, an occlusion is formed between the transmitting end and the receiving end, causing a change in the intensity of the optical signal received by the receiving end.

[0030] The scanner 6 can reciprocally move under the action of the drive device to scan the inside of the wafer cassette 9; multiple wafers can be placed in the wafer cassette 9 at one time. For example, a foup (front - opening unified pod) has 25 slots and can hold 25 wafers at one time. Since the scanning range of the scanner at one time is limited, a drive device is set to drive the scanner to reciprocally move so as to complete the automatic scanning of all wafers in the wafer cassette.

[0031] The scanner preferably uses an LED reflective photoelectric sensor. Since the slots in the wafer cassette are fixed and the relative distance between two adjacent wafers in the normal state is fixed, there will be a relatively fixed reflected light position; when a certain wafer is inserted obliquely, the reflected light position of the scanner between these two adjacent wafers will be abnormal, so that it can be determined whether the wafer is inserted obliquely.

[0032] Under normal circumstances, the slots in the wafer cassette are in a horizontal state, and the wafers are also placed horizontally on the slots. Multiple slots and wafers are vertically arranged in the wafer cassette. Therefore, the driving device is preferably a lifting device, which can drive the scanner to scan all the slots and wafers in the wafer cassette from top to bottom.

[0033] The control system 1 is electrically connected to the scanner 6 and the wafer anti-protrusion detection sensor 8, and is used to receive the detection information of the scanner 6 and the wafer anti-protrusion detection sensor 8, and judge whether the placement position of the wafers in the wafer cassette is accurate according to the detection information. The control system can adopt a PLC control system to control signal input, output and simple logical operations, and automatically judge whether the placement position of the wafers in the wafer cassette is correct, whether there is skew insertion or protrusion outside the wafer cassette through the information of the wafer anti-protrusion detection sensor and the scanner, improving the detection efficiency and accuracy.

[0034] As can be understood by those skilled in the art, the scanner, the driving device, and the wafer anti-protrusion detection sensor can be directly set on the working platform 11 of the machine tool Load Port. Before the wafer cassette is placed on the working platform and the robotic arm picks up the wafer, the placement position of the wafers in the wafer cassette is detected. When the detection result is normal, the robotic arm picks up the wafer from the wafer cassette for the next process. When the detection result is abnormal, the machine tool stops, and manual re-inspection is carried out to pick out the skew-inserted and other mis-placed wafers.

[0035] Preferably, the device for automatically scanning and detecting the placement position of wafers provided in this application further includes a protective barrier 7, and the protective barrier 7 and the wafer cassette 9 are located on opposite sides of the scanner respectively. The protective barrier forms an effective safety protection for the scanner and prevents the external environment from affecting the normal operation of the scanner.

[0036] Furthermore, the protective barrier 7 is provided with a height adjustment device. When the scanner is not working, the scanning barrier is lowered to facilitate the robotic arm to pick up and place the wafer cassette and other operations. When the scanner is working, it is raised to protect the scanner.

[0037] Preferably, the device for automatically scanning and detecting the placement position of wafers provided in this application further includes a start button 2 electrically connected to the control system, and the start button 2 is used to control the start of the entire device.

[0038] The control system 1 is also electrically connected to the driving device 5 and the height adjustment device of the protective barrier 7. Through the control system, the lifting device and the height adjustment device can be controlled to run and shut down automatically, realizing the automatic control of the entire detection process.

[0039] Preferably, the device for automatically scanning and detecting the placement position of the wafer provided by the present application further includes a signal indicator light electrically connected to the control system to indicate the detection result. Specifically, the signal indicator light includes an "Enable light" 12 and a three-color signal light 13. The three-color signal light includes three color lights: red, green, and yellow. The red signal light is used to indicate that the machine is in an abnormal state, the green signal light is used to indicate that the machine is in a normal operating state, and the yellow signal light is used to indicate that the machine is in a state of waiting for materials. When the detection result is normal, the "Enable light" lights up. When the detection result is abnormal, the "red signal light" lights up to alert people's attention.

[0040] Preferably, the control system 1 is electrically connected to each component through a flexible cable 3. The flexible cable 3 is selected for signal transmission considering that it may move randomly with the mechanism.

[0041] Preferably, the device for automatically scanning and detecting the placement position of the wafer provided by the present application further includes a linear slide rail 4. The driving device can move along the linear slide rail 4. By setting the linear slide rail, the smoothness of the movement of the scanner is improved, and the influence of the movement on the scanner is reduced.

[0042] Preferably, the linear slide rail 4 is located below the working platform 11. The working platform is provided with a first installation groove, a second installation groove, and a third installation groove for installing a wafer anti-protrusion detection sensor, a protective barrier, and a scanner respectively. There is also a hole for the driving device to move on the working platform below the third installation groove.

[0043] Preferably, the working platform is also provided with a stopper 10 for positioning the wafer cassette.

[0044] The signal indicator light and the stopper can adopt the signal indicator light and the stopper of the original machine's Load Port. It is only necessary to electrically connect the signal indicator light to the control system with a flexible cable.

[0045] The specific working process of the present application is as Figure 4 shown as follows:

[0046] Place the wafer cassette containing wafers on the Load Port; click the start button 2, and the start signal is transmitted to each controlled component through the control system 1; at this time, control the protective barrier 7 to rise; the wafer anti-protrusion detection sensor 8 checks the protrusion state of the wafer. If the wafer protrudes, the red light of the three-color signal light lights up and the machine action stops; if the wafer does not protrude, control the driving device 5 to move up and down, and the scanner 6 scans the wafers in the wafer cassette. The scanning result is transmitted to the control system through the flexible cable 3 for discrimination; if the scanning result is abnormal, the red light of the three-color signal light lights up and the machine action stops; if the scanning result is normal, the "Enable light" of the machine lights up, and the robotic arm starts to pick up wafers from the wafer cassette for measurement.

[0047] Although the preferred embodiments of the present utility model have been described, those skilled in the art can make additional changes and modifications to these embodiments once they learn the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments as well as all changes and modifications that fall within the scope of the present utility model. Obviously, those skilled in the art can make various changes and variations to the present utility model without departing from the spirit and scope of the present utility model. Thus, if these modifications and variations of the present utility model fall within the scope of the claims of the present utility model and its equivalent technologies, the present utility model also intends to include these modifications and variations.

Claims

1. An apparatus for automatically scanning and detecting the placement position of a wafer, which is used to detect whether the placement position of the wafer in the wafer cassette is accurate. The wafer cassette has multiple layers of wafer placement slots, and is characterized in that, The device for automatically scanning and detecting the wafer placement position includes a scanner, a driving device connected to the scanner, a wafer anti-protrusion detection sensor, and a control system; The wafer anti-protrusion detection sensor is used to detect whether the wafer protrudes outside the wafer cassette; The scanner can reciprocate under the action of the driving device to scan the inside of the wafer cassette; The control system is electrically connected to the scanner and the wafer anti-protrusion detection sensor, and is used to receive the detection information of the scanner and the wafer anti-protrusion detection sensor, and judge whether the wafer placement position in the wafer cassette is accurate according to the detection information.

2. The device for automatically scanning and detecting the wafer placement position according to claim 1, wherein it further includes a protective barrier, and the protective barrier and the wafer cassette are respectively located on opposite sides of the scanner.

3. The device for automatically scanning and detecting the wafer placement position according to claim 2, wherein the protective barrier is provided with a height adjustment device.

4. The device for automatically scanning and detecting the wafer placement position according to claim 1, wherein it further includes a start button electrically connected to the control system, and the start button is used to control the start of the entire device.

5. The device for automatically scanning and detecting the wafer placement position according to claim 3, wherein the control system is also electrically connected to the driving device and the height adjustment device of the protective barrier.

6. The device for automatically scanning and detecting the wafer placement position according to claim 1, wherein it further includes a signal indicator light electrically connected to the control system; the signal indicator light includes an "enabled light" and a three-color signal light; the three-color signal light includes red, green, and yellow lights. The red signal light is used to indicate that the machine is in an abnormal state, the green signal light is used to indicate that the machine is in a normal operation state, and the yellow signal light is used to indicate that the machine is in a waiting-for-material state.

7. The device for automatically scanning and detecting the wafer placement position according to claim 1, wherein the scanner is located at the rear side of the wafer cassette, and the wafer anti-protrusion detection sensor is located at the front side of the wafer cassette.

8. The device for automatically scanning and detecting the wafer placement position according to claim 2 or 3, wherein it further includes a linear slide rail, and the driving device can move along the linear slide rail.

9. The device for automatically scanning and detecting the wafer placement position according to claim 8, wherein it further includes a working platform for placing the wafer cassette, and the linear slide rail is located below the working platform; the working platform is provided with a first installation groove, a second installation groove, and a third installation groove for installing the wafer anti-protrusion detection sensor, the protective barrier, and the scanner respectively. There is also a hole for the driving device to move on the working platform below the third installation groove.

10. The device for automatically scanning and detecting the wafer placement position according to claim 9, wherein the working platform is also provided with a stop block for positioning the wafer cassette.

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