Wafer Cassette Dark Vision Device

Abstract

Provided is a wafer cassette dark vision device for preventing damage to a wafer due to accidental contact by a robot arm. 【Solution means】The wafer cassette dark vision device includes a wafer cassette 1 that houses a plurality of wafers 11 arranged in parallel, a plurality of gap portions 111, a wafer transfer device 2, a robot arm 21, and a dark vision device 3. The dark vision device includes an infrared spectroscopic radiation component 31, a radiation detection component 32, and an image conversion component 33 for generating a visible light image, and further includes a state detection module 4 and a control module 5. Thereby, before the wafer transfer device grasps the wafer, the infrared spectroscopic radiation component of the dark vision device is used to irradiate the gap portion with infrared rays, the reflected light rays are received by the radiation detection component, and further, a visible light image is generated by the image conversion component, and the state detection module determines the storage state of the wafer at the back of the gap portion. Finally, the control module determines the operation of the robot arm.

Description

Technical Field

[0001] The present invention relates to a wafer cassette dark vision device, and in particular, to a wafer cassette dark vision device that has a simple and convenient installation method, a relatively low structural cost, a rapid identification method, and can detect in detail the storage state of wafers inside the wafer cassette, thereby preventing damage to the wafers caused by accidental contact of the robotic arm.

Background Art

[0002] Generally, wafers are stored in a wafer case and, after being taken out of the wafer case by a transport device, proceed to processes such as cutting and detection. In order to prevent damage to the wafers during the process of loading and unloading the wafers, it is necessary to confirm whether there are any defective arrangements such as missing, overlapping, distorted, or warped states in the wafers arranged in the wafer case before taking out the wafers. Therefore, before all the wafers in the wafer case are taken out, a detection operation of the storage state of the wafers in the wafer case is performed, and if the arrangement of the wafers is not appropriate, the loading and unloading are interrupted until the user releases the error state.

[0003] Conventional detection methods include methods such as manual detection, infrared blocking sensors, proximity sensors, or complex optical image recognition systems. However, when using the above-mentioned detection methods, the following problems and drawbacks exist and improvement is expected.

[0004] First, there are many system facilities and the detection procedure is complex, resulting in a low matching rate of the optical image recognition system.

[0005] Second, since it is necessary to install a large number of sensors, the installation cost is relatively high, or the volume is relatively large, which is disadvantageous when arranging the entire equipment in the space.

[0006] Thirdly, although the storage state of the wafer can only be confirmed by the part visible to the naked eye from the outside of the wafer case, the thickness of the wafer is very thin. Even if the storage state seems normal from the outside, there may be warping inside. Since any of the above detection methods cannot detect whether there is an abnormality in the internal storage state, there is a high risk of damaging the wafer when the transfer device takes the wafer in and out.

Summary of the Invention

Problems to be Solved by the Invention

[0007] The purpose of the present invention is to provide a wafer cassette dark vision device that can detect in detail the storage state of the wafer inside the wafer cassette and further prevent damage to the wafer caused by accidental contact of the robot arm by controlling the operation of the robot arm.

Means for Solving the Problems

[0008] To achieve the above object, the structure of the present invention comprises a wafer cassette, a plurality of wafers, a plurality of gap portions, a wafer transfer device, a robot arm, and a dark vision device. The dark vision device comprises an infrared spectroscopic emission component, a radiation detection component, and an image conversion component for generating a visible light image, and further comprises a state detection module and a control module. Among them, the plurality of wafers are arranged and accommodated in parallel in the wafer cassette. Each of the gap portions is defined between the wafers or between the wafer and the wall surface of the wafer cassette. The wafer transfer device is provided on one side of the wafer cassette, and the robot arm is pivotally provided on the wafer transfer device. The dark vision device is provided on the robot arm, and the emission direction of the infrared spectroscopic emission component coincides with the gripping direction of the robot arm and enters the gap portion. The radiation detection component is provided on one side of the infrared spectroscopic emission component to receive the reflected light of the infrared spectroscopic emission component and convert the reflected light into an electrical signal. The image conversion component performs data cooperation with the radiation detection component to calculate and process the electrical signal to generate a visible light image. The state detection module performs data cooperation with the dark vision device and determines the storage state of each wafer based on the visible light image. The control module performs data cooperation with the state detection module. When reading a storage state without abnormality, it drives the robot arm to enter the gap portion.

[0009] When the wafer transfer device grips the wafer in the wafer cassette, first, the infrared spectroscopic emission component of the dark vision device is used to irradiate the gap portion with infrared rays, and the radiation detection component receives the reflected light. Further, after the image conversion component converts the reflected light into an electrical signal, a visible light image is generated. Further, the state detection module determines the storage state of the wafer at the back of the gap portion based on the visible light image. Finally, the control module determines the operation of the robot arm. Thereby, it is possible to prevent the robot arm from making accidental contact due to a problem in the storage state of the wafer, thereby damaging the wafer.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 3A

Figure 4

Figure 4A

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0011] Refer to FIGS. 1 and 2. FIGS. 1 and 2 are a perspective view and a view showing the usage state of a preferred embodiment in the present invention. As can be seen from the figures, the present invention comprises a wafer cassette 1, a wafer transfer device 2, a robot arm 21, and a dark vision device 3.

[0012] The wafer cassette 1 houses a plurality of wafers 11 arranged in parallel, and a gap portion 111 is provided between each of the wafers 11 or between each of the wafers 11 and the wall surface of the wafer cassette 1.

[0013] The wafer transfer device 2 is provided on one side of the wafer cassette 1.

[0014] The robot arm 21 is pivotally provided on the wafer transfer device 2.

[0015] The dark vision device 3 is provided on the robot arm 21 and includes an infrared spectroscopic radiation component 31, a radiation detection component 32, an image conversion component 33, a state detection module 4, a collation module 42, and a control module 5.

[0016] The emission direction of the infrared spectroscopic emission component 31 is the same as the gripping direction of the robot arm 21 and enters the gap 111.

[0017] The radiation detection component 32 is provided on one side of the infrared spectroscopic emission component 31 to receive the reflected light of the infrared spectroscopic emission component 31 and convert the reflected light into an electrical signal.

[0018] The image conversion component 33 performs computational processing on the electrical signal in data communication with the radiation detection component 32 to generate a visible light image.

[0019] The state detection module 4 performs data communication with the night vision device 3 to determine the storage state of each wafer 11 based on the visible light image, and the state detection module 4 performs data communication with the state database 41.

[0020] The collation module 42 is provided on one side of the state database 41 to collate the visible light image with the state database 41 to determine whether the storage state is normal.

[0021] The control module 5 performs data communication with the state detection module 4. When the storage state without abnormality is read, the control module 5 drives the robot arm 21 to enter the gap 111.

[0022] Among them, the wafer 11 is an abbreviation for a semiconductor crystal circular piece (Wafer), and the wafer transfer device 2 is taken as an example of a semiconductor automatic transfer device (Equipment Front End Module, EFEM). Inside the gap 111 is a space with low illuminance or dark that cannot be seen with the naked eye inside the wafer cassette 1. The infrared spectroscopic radiation component 31 takes infrared LED illumination as an example and illuminates the target area with visible or invisible infrared rays. The radiation detection component 32 is an image sensor and detects by any one of the technologies of Complementary Metal-Oxide-Semiconductor (CMOS) or Charge-Coupled Device (CCD). The image conversion component 33 takes a signal processing device as an example and is used to convert an electrical signal into a digital signal and then perform computational processing to generate an image. The state detection module 4 is a processor provided in a cloud processing device or the wafer transfer device 2. In this embodiment, the latter is taken as an example. The collation module 42 is one chip in the processor, and the state database 41 is a storage medium such as a memory or a hard disk. The control module 5 is another processor provided in another cloud processing device or the wafer transfer device 2. All are indicated by a wavy frame in the figure. However, the corresponding forms of the above-described components are only examples of preferred embodiments, and any form having the same function belongs to the scope of the present invention and is not limited to the above examples.

[0023] From the above description, the structure of this technology can be understood. By corresponding and combining this structure, the installation method can be made simple and convenient, the structure cost can be reduced, the identification method can be made rapid, the storage state of the wafer 11 inside the wafer cassette 1 can be detected in detail, and damage to the wafer due to accidental contact of the robot arm 21 can be prevented. Details will be described below.

[0024] Refer to FIGS. 1 to 5 simultaneously. FIGS. 1 to 5 are perspective views to operational block diagrams of preferred embodiments in the present invention. When assembling the above-described components, as can be seen from the figures, regarding the arrangement of the equipment unit, when installing the low-light vision device 3 on the existing robot arm 21, the installation is completed only by transmitting signals between the low-light vision device 3 and the wafer transfer device 2, either wired or wirelessly. Since the structure is relatively simple and there is no need to add installation space, the required cost is also relatively low. When installing, keep the emission direction of the infrared spectroscopic emission component 31 and the gripping direction of the robot arm 21 in the same direction so that infrared rays enter the gap portion 111. In this way, no matter in which direction or at which height position the robot arm 21 grips the wafer 11, the low-light vision device 3 can move and swing simultaneously, and by installing only a single low-light vision device 3, the storage state of the wafer can be easily identified.

[0025] In particular, the light source of the identification light ray used in the present invention is the infrared spectroscopic emission component 31, and the infrared spectroscopic emission component 31 provides infrared rays with a wavelength of, for example, from 850 nm to 940 nm, with infrared rays of 850 nm being preferred. This wavelength region is visible light, but there is no need to conceal the light ray in the semiconductor manufacturing process, and since this wavelength region provides a relatively strong illumination effect, the sensitivity of a plurality of image sensors (including the radiation detection component 32 of the present invention) to the light in this wavelength region is also relatively high. The infrared rays in this wavelength region are particularly used in a low-illuminance space or a dark space, and when the target object is irradiated with infrared rays, it reflects the infrared rays. At this time, the radiation detection component 32 is used to receive the reflected infrared rays, convert the optical signal or radiation signal of the reflected light into an electrical signal, and transmit it to the image conversion component 33 for processing. Further, the image conversion component 33 performs processes such as noise removal, contrast adjustment, gamma correction, and color processing to convert the electrical signal into a pseudo-color image. This is a visible light image that can be identified by the naked eye.

[0026] That is, the visible light image acquired by the low-light vision device 3 can clearly display the storage state of the wafers located at the back of the gap 111, thus solving the drawback that the storage status inside the wafer cassette 1 existing in various conventional detection methods cannot be sensed. Naturally, after acquiring the visible light image, it is necessary to further confirm the storage state of each wafer 11 via the state detection module 4. Therefore, the collation module 42 is used to collate the visible light image with the images in the state database 41. Regarding the source of the images in the state database 41, a wafer cassette 1 that accommodates a plurality of wafers 11 and has been confirmed to have no abnormality in the storage state is prepared for identification, and the collation data of the reference storage state is provided to the state database 41 in advance. Thereby, by collating each visible light image, it is determined whether the storage state of the wafer at the corresponding position is normal.

[0027] The control module 5 reads the judgment result of the state detection module 4. When reading the storage state of a normal wafer, it drives the robot arm 21 to enter the corresponding gap 111 and take in and out the wafer 11. On the contrary, when reading the storage state of an abnormal wafer, for example, when it is any one of inclination, overlap, omission, or warping, the control module 5 stops the operation of the robot arm 21 from entering the gap 111 and makes the robot arm 21 move to the next gap 111 via the wafer transfer device 2. In this way, every time the robot arm 21 takes in and out the wafer 11, it acquires the visible light image at the back of the gap 111 by using the low-light vision device 3. Only when the state detection module 4 determines that there is no abnormality, the control module 5 makes the robot arm 21 perform the take-in and out operation. This identification operation is not only simple and rapid, but also can surely prevent the blind spot that even if the external storage state in the wafer cassette 1 is normal, the internal storage state is abnormal. Therefore, the safety of the take-in and out operation by the robot arm 21 can be effectively enhanced, and damage to the wafer 11 can be prevented.

[0028] Refer to FIG. 6 simultaneously. FIG. 6 is a perspective view of a more preferred embodiment of the present invention. As can be seen from the figure, this embodiment is substantially the same as the above-described embodiment. The difference is that the night vision device 3 is provided with at least one angle adjustment component 6, and by adjusting the emission angle of the infrared spectroscopic emission component 31, infrared rays can surely enter the depth of the gap portion. The angle adjustment component 6 can be a method such as knob adjustment, slide adjustment, or electric adjustment. Among them, knob adjustment can be achieved by simply adjusting the angle with a screw by installing a knob on the outside of the night vision device 3 and connecting the inner infrared spectroscopic emission component 31 with a screw. This method has a simple structure and operation, and since the infrared spectroscopic emission component 31 does not need to be aligned with other light sources, there is no need to worry about the problem of the discrimination rate due to ghosts. Slide adjustment uses a housing with a hollow arc-shaped rail 61, slides inside the arc-shaped rail 61, and combines with a screw 62 fixed to the infrared spectroscopic emission component 31 to adjust the angle. This method can be installed on both sides of the infrared spectroscopic emission component 31 at the same time, so the fixing strength can be increased, and the angle position can be prevented from shifting due to the long-term operation of the robot arm 21. Electric adjustment is similar to the knob adjustment method. The difference is that by changing the knob to a motor, the angle can be adjusted more accurately semi-automatically. In this embodiment, only slide adjustment is illustrated.

Description of the reference numerals

[0029] 1 Wafer cassette 11 Wafer 111 Gap portion 2 Wafer transfer device 21 Robot arm 3 Night vision device 31 Infrared spectroscopic emission component 32 Radiation detection component 33 Image conversion component 4 State detection module 41 State database 42 Collation module 5 Control module 6 Angle adjustment component 61 Arc-shaped rail 62 Screw

Claims

1. A wafer cassette night vision device comprising a wafer cassette, a plurality of wafers, a wafer transport device, a robot arm, and a night vision device, the wafer cassette accommodates a plurality of wafers arranged in parallel, and has gaps between each of the wafers or between each of the wafers and a wall surface of the wafer cassette; the wafer carrying device is disposed on one side of the wafer cassette, the robot arm is pivotally mounted to the wafer transport device; The night vision device is provided on the robot arm and includes an infrared spectral radiation component, a radiation detection component, an image conversion component, a state detection module, and a control module; The emission direction of the infrared spectral radiation component is the same as the gripping direction of the robot arm and enters the gap portion; The radiation detection component is disposed on one side of the infrared spectroscopic radiation component to receive the reflected light of the infrared spectroscopic radiation component and convert the reflected light into an electrical signal; the image conversion component in data communication with the radiation detection component for processing the electrical signals to generate a visible light image; The state detection module determines a storage state of each of the wafers based on the visible light image by data linking with the night vision device; A wafer cassette night vision device characterized in that the control module, by data linking with the status detection module, drives the robot arm to enter the gap when it reads the storage status as normal.

2. The wafer cassette night vision device of claim 1, wherein the radiation detection component is an image sensor and detects by any one of complementary metal-oxide-semiconductor (CMOS) or charge-coupled device (CCD) technologies.

3. 2. The wafer cassette night vision device according to claim 1, wherein the state detection module is data linked to a state database.

4. 4. The wafer cassette night vision device according to claim 3, further comprising a comparison module provided on one side of the state database, for comparing the visible light image with the state database to determine whether the storage state is normal.

5. 2. The wafer cassette night vision device according to claim 1, wherein the storage state is any one of normal, tilted, overlapped, missing, and warped.

6. 2. The wafer cassette night vision device according to claim 1, wherein the inside of the gap is a space that cannot be seen with the naked eye in low illumination or darkness.

7. 2. The wafer cassette night vision device according to claim 1, wherein the night vision device comprises at least one angle adjustment component for adjusting the emission angle of the infrared spectral radiation component.

Images