Microscope detection equipment with transparent wafer positioning function

Abstract

A microscope detection device with a transparent wafer positioning function disclosed by the present invention comprises a detection seat, the top of the detection seat is sequentially provided with a loading unit, a calibration unit and a detection unit from left to right, and the loading unit comprises a wafer box for loading wafers. The left side and the right side of the wafer box are respectively provided with a transmitting device and a sensing device which are fixedly installed on the detection seat. And the calibration unit comprises a buffer vacuum disc fixed on the detection seat. According to the invention, the position information of the transparent and semitransparent wafer is detected, the angle of the wafer is conveniently positioned, the detection effect of the microscope is improved, the detection difficulty of the transparent and semitransparent wafer is reduced, and the detection precision of the transparent and semitransparent wafer is improved by utilizing the refraction effect of the transparent and semitransparent wafer and obliquely arranging the laser sensor through the refraction parallel error of light. The purpose of detecting the transparent and semitransparent wafer is achieved.

Description

Technical Field

[0001] The present invention relates to the field of wafer detection technology, and more specifically to a microscope detection device with the function of positioning a transparent wafer. Background Art

[0002] Wafer microscope is mainly used to detect surface defects, breakage and scratches of opaque wafers. The equipment includes loading unit, calibration unit and detection unit. The loading unit is composed of wafer box and laser sensor bracket, and has the functions of wafer scanning and wafer placement. The calibration unit is composed of center positioning sensor, flat edge / notch positioning sensor, exchange arm, pick-and-place arm, wafer back visual inspection arm and buffer vacuum plate, and has the functions of angle positioning and visual inspection of the back of wafer for defects. The detection unit is composed of microscope, vacuum stage, etc., and further detects wafer surface defects through magnifying glass and mobile platform.

[0003] Due to problems with the equipment's light source and components, it can only identify and detect ordinary opaque wafers, but cannot identify and detect existing new transparent or translucent wafers, which causes certain deficiencies and impacts on wafer production and inspection. The positioning sensors of existing microscope inspection equipment cannot detect transparent or translucent wafers, which is mainly caused by the inability of the detection sensor to identify them. Due to insufficient laser power of the original sensor and low sensitivity of the photosensitive element at the receiving end, the equipment itself is unable to judge the signal of the detection result. Summary of the invention

[0004] In view of the problems existing in the prior art, the purpose of the present invention is to provide a microscope inspection device with the function of positioning a transparent wafer, which facilitates the positioning of the wafer angle and reduces the difficulty of detecting transparent and semi-transparent wafers, thereby achieving the purpose of detecting transparent and semi-transparent wafers and improving the detection effect.

[0005] To achieve the above object, the present invention adopts the following technical solution: A microscope detection device with a transparent wafer positioning function comprises a detection seat, a loading unit, a calibration unit and a detection unit are sequentially installed on the top of the detection seat from left to right, the loading unit comprises a wafer box for loading wafers, and a transmitting device and a sensing device fixedly installed on the detection seat are respectively arranged on the left and right sides of the wafer box; The calibration unit comprises a buffer vacuum plate installed on the detection seat, a motor for driving the buffer vacuum plate to rotate is installed at the bottom of the detection seat, and a flat edge positioning sensor, a center positioning sensor, a wafer backside visual inspection arm, a first exchange arm and a pick-and-place arm are installed on the detection seat. The detection unit comprises a second exchange arm mounted on the detection seat, a microscope is mounted on the second exchange arm, and a vacuum stage is mounted on the microscope; The transmitting device comprises a fixed bracket, an adjusting bracket and a signal amplifier are mounted on the fixed bracket, a first laser transmitter is fixedly mounted on the adjusting bracket, and the sensing device comprises a first sensor for receiving a signal from the first laser transmitter; The flat edge positioning sensor includes a second laser emitter and a second sensor for receiving the light signal of the second laser emitter. The light emission path of the second laser emitter is inclined to the placement plane on the top of the buffer vacuum disk. A concave mirror is arranged at the bottom of the second sensor, wherein the concave mirror is parallel to the signal receiving surface of the second sensor.

[0006] As a further description of the above technical solution: The number of the flat edge positioning sensor is at least one, and the angle between the second laser emitter and the placement plane of the top of the buffer vacuum plate is sixty degrees.

[0007] As a further description of the above technical solution: A support seat is fixedly mounted on the detection seat, and the concave mirror is fixedly mounted on the support seat. The support seat is in a C-shape.

[0008] As a further description of the above technical solution: The loading unit includes an electric lifting rod fixedly mounted on the detection seat, and a placement platform is fixedly mounted on the output end of the top of the electric lifting rod, and the maximum rising height of the placement platform is greater than the highest height of the first laser emitter.

[0009] As a further description of the above technical solution: A restraining tube is arranged on the side of the concave mirror facing the second laser emitter. The restraining tube is located at the center of the concave mirror and is fixedly mounted on the supporting seat.

[0010] As a further description of the above technical solution: The adjusting bracket is rotatably mounted on the fixing bracket via a rotating shaft, a fastening screw is threadedly connected to the fixing bracket, a contact block is rotatably mounted on one end of the fastening screw located inside the fixing bracket, and the other end of the contact block contacts the rotating shaft of the adjusting bracket.

[0011] As a further description of the above technical solution: The first sensor and the second sensor both generate voltage measurements through photosensitive elements.

[0012] Compared with the prior art, the advantages of the present invention are: This scheme utilizes the refraction effect of transparent and semi-transparent wafers, sets the laser sensor at an angle, and detects the position information of the transparent and semi-transparent wafer through the refraction parallel error of the light, thereby facilitating the positioning of the wafer angle, improving the detection effect of the microscope, reducing the difficulty of detecting transparent and semi-transparent wafers, and achieving the purpose of detecting transparent and semi-transparent wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the top view of the structure of the present invention; Figure 2 It is a schematic diagram of the structure of the launch device of the present invention; Figure 3 It is a schematic diagram of the connection structure between the fixed bracket and the adjustable bracket of the present invention; Figure 4 It is a schematic diagram of the laser light path when the flat edge positioning sensor of the present invention does not detect the wafer notch; Figure 5 This is a schematic diagram of the laser light path structure when the flat edge positioning sensor of the present invention detects wafer notches.

[0014] Description of the numbers in the figure: 100, detection seat; 200, loading unit; 210, wafer box; 220, launching device; 221, fixing bracket; 222, adjusting bracket; 223, first laser emitter; 224, contact block; 225, fastening screw; 226, signal amplifier; 230, sensing device; 231, first sensor; 240, electric lifting rod; 250, placement platform; 300, calibration unit; 310, buffer vacuum plate; 320, flat edge positioning sensor; 321, second laser emitter; 322, second sensor; 323, concave mirror; 324, supporting seat; 325, restraining tube; 330, center positioning sensor; 340, wafer back side visual inspection arm; 350, first exchange arm; 360, pick and place arm; 400, detection unit; 410, second exchange arm; 420, microscope; 430, vacuum stage. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0016] Transparent wafers, like non-transparent wafers, are usually designed with specific marks on their edges, such as flat edges or notches, for positioning and orientation identification. These marks are important reference points during the manufacturing and testing process of the wafer, ensuring that the wafer is mounted and handled in the correct orientation in subsequent processing steps.

[0017] See also Figure 1-5 , the present invention provides the following embodiments: A microscope inspection device with a function of positioning a transparent wafer comprises an inspection seat 100, on the top of which a loading unit 200, a calibration unit 300 and a detection unit 400 are sequentially installed from left to right, and is characterized in that: the loading unit 200 comprises a wafer box 210 for loading wafers, and the left and right sides of the wafer box 210 are respectively provided with an emitting device 220 and a sensing device 230 fixedly mounted on the inspection seat 100, the loading unit 200 comprises the wafer box 210, and the emitting device 220 and the sensing device 230 constitute a wafer scanning function.

[0018] The calibration unit 300 includes a buffer vacuum plate 310 installed on the detection base 100, and a motor (not shown in the figure) is installed at the bottom of the detection base 100 for driving the buffer vacuum plate 310 to rotate. The detection base 100 is installed with a flat edge positioning sensor 320, a center positioning sensor 330, a wafer back side visual inspection arm 340, a first exchange arm 350 and a pick-and-place arm 360 distributed around the buffer vacuum plate 310. The flat edge positioning sensor 320 and the center positioning sensor 330 respectively detect the center of the wafer and cooperate with the flat edge notch on the transparent wafer for angular positioning, and the pick-and-place arm 360 is used for the wafer pick-and-place turnover work between the loading unit 200 and the buffer vacuum plate 310.

[0019] The detection unit 400 includes a second exchange arm 410 installed on the detection base 100, a microscope 420 is installed on the second exchange arm 410, and a vacuum stage 430 is installed on the microscope 420, wherein the second exchange arm 410 cooperates with the first exchange arm 350 to act on the wafer turnover between the vacuum stage 430 and the buffer vacuum plate 310, and then the wafer surface is magnified and displayed for detection through the microscope 420.

[0020] The wafer box 210 with wafers is placed on the platform, and the first laser emitter 223 and the first sensor 231 are used to confirm the specific position of the wafer after scanning; after scanning and identification, the pick-and-place arm 360 picks up the wafer, and the center positioning sensor 330 determines the state of the wafer picking; after the pick-and-place arm 360 runs to the preset position, the wafer is fixed on the buffer vacuum plate 310, and the buffer vacuum plate 310 drives the wafer to rotate and identifies the notch or flat edge of the wafer through the flat edge positioning sensor 320; after the angle positioning is completed, the first exchange arm 350 and the second exchange arm 410 are sent to the vacuum mirror stage 430 for microscope 420 magnification detection, wherein the first exchange arm 350 and the second exchange arm 410 no longer change the angle of the wafer that has been angle-positioned during the wafer turnover process.

[0021] The emitting device 220 includes a fixed bracket 221 , on which an adjusting bracket 222 and a signal amplifier 226 are mounted, on which a first laser emitter 223 is fixedly mounted, and the sensing device 230 includes a first sensor 231 for receiving signals from the first laser emitter 223 .

[0022] Laser irradiation causes the photosensitive element at the receiving end to generate voltage. The device mainboard determines whether the wafer is detected by analyzing and calculating the voltage threshold and difference. By increasing the laser intensity at the transmitting end and narrowing the range of the voltage threshold and difference at the receiving end to meet the calculation requirements of the device mainboard, the purpose of detecting transparent wafers is achieved.

[0023] The flat edge positioning sensor 320 includes a second laser emitter 321 and a second sensor 322 for receiving the optical signal of the second laser emitter 321. The light emitting path of the second laser emitter 321 is inclined to the placement plane on the top of the buffer vacuum plate 310. A concave mirror 323 is arranged at the bottom of the second sensor 322, wherein the concave mirror 323 is parallel to the signal receiving surface of the second sensor 322.

[0024] The second laser emitter 321 irradiates the wafer at an angle, and the refraction effect of the wafer makes the light path of the laser emission parallel to the light path of the incident light. Therefore, the path of the laser emitted by the second laser emitter 321 will have a parallel deviation after passing through the wafer. Therefore, whether the second sensor 322 receives the second laser emitter 321 represents two detection conditions for the transparent and semi-transparent wafer. The second sensor 322 receives the light information of the second laser emitter 321, which means that the laser has not passed through the wafer, and the second sensor 322 does not receive the light information of the second laser emitter 321, which means that the laser has passed through the wafer. In this way, the position information of the wafer notch or flat edge positioning feature is determined to detect the wafer, so as to achieve the purpose of locating the wafer angle.

[0025] When the sensing range error of the second sensor 322 is relatively large, the concave mirror 323 is provided so that light can only pass through the center of the concave mirror 323 in a straight line without changing the direction of the light, and the light will be refracted when passing through other parts except the center, thereby expanding the detection accuracy of the second sensor 322 and reducing the detection error.

[0026] The number of the flat edge positioning sensor 320 is at least one, and the angle between the second laser emitter 321 and the placement plane of the top of the buffer vacuum plate 310 is sixty degrees.

[0027] According to the wafer notch or flat edge positioning feature information detection needs of the wafer, an appropriate number of flat edge positioning sensors 320 are selected and set. The tilt angle of the second laser emitter 321 determines that the angle of the light emitted to the wafer plane is 60 degrees, which is convenient for the laser to refract and for calculating the formula using the Pythagorean theorem to obtain the angle data of the wafer. See also Figure 5 The degree of the angle α is 60°, the height of the emitting end of the second laser emitter 321 from the bottom of the wafer is h, and the horizontal distance of the laser incident on the wafer is a. Therefore, the horizontal distance of the notch from the second laser emitter 321 can be accurately obtained to determine the angular position information of the wafer.

[0028] A support base 324 is fixedly mounted on the detection base 100 , and the concave mirror 323 is fixedly mounted on the support base 324 . The shape of the support base 324 is C-shaped.

[0029] The concave mirror 323 and the second sensor 322 are supported by the support base 324, which does not hinder the movement of the wafer and satisfies the need to receive laser light information.

[0030] A restraining tube 325 is disposed on one side of the concave mirror 323 facing the second laser emitter 321 . The restraining tube 325 is located at the center of the concave mirror 323 , and is fixedly mounted on the supporting seat 324 .

[0031] The constraining tube 325 is provided to determine the range and angle of the light that can be directed to the second sensor 322, thereby further improving the accuracy of light sensing detection.

[0032] The loading unit 200 includes an electric lifting rod 240 fixedly mounted on the detection seat 100 , and a placement platform 250 is fixedly mounted on the output end of the top of the electric lifting rod 240 . The maximum rising height of the placement platform 250 is greater than the highest height of the first laser emitter 223 .

[0033] The placement platform 250 can be raised and lowered by the electric lifting rod 240. When the electric lifting rod 240 drives the placement platform 250 to descend, the wafer position can be detected by the transmitting device 220 and the sensing device 230. After the preliminary position detection is completed, when the wafer needs to be moved to the calibration unit 300 area, the electric lifting rod 240 can drive the placement platform 250 to rise, making it convenient for the pick-up and place arm 360 to clamp the wafer through the top of the fixed bracket 221.

[0034] The adjusting bracket 222 is rotatably mounted on the fixing bracket 221 via a rotating shaft. A fastening screw 225 is threadedly connected to the fixing bracket 221. A contact block 224 is rotatably mounted on one end of the fastening screw 225 located inside the fixing bracket 221. The other end of the contact block 224 contacts the rotating shaft of the adjusting bracket 222.

[0035] The bracket 222 can be easily adjusted to rotate on the fixed bracket 221 through the rotating shaft, and the fastening screw 225 is rotated to control the contact between the contact block 224 and the rotating shaft to fix the rotation, so as to adjust the emission angle of the first laser emitter 223 and facilitate adjustment.

[0036] The first sensor 231 and the second sensor 322 both generate voltage measurements through photosensitive elements.

[0037] To sum up, the present invention can target transparent and semi-transparent wafers and utilize the refraction effect of transparent and semi-transparent wafers to design a corresponding detection system to detect the position information of the transparent and semi-transparent wafers, facilitate the positioning of the wafer angle, improve the detection effect of the microscope, reduce the difficulty of detecting transparent and semi-transparent wafers, and achieve the purpose of detecting transparent and semi-transparent wafers.

[0038] The above is only a preferred specific implementation of the present invention; however, the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solution and its improved conception within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A microscope inspection device with a transparent wafer positioning function, comprising an inspection seat (100), a loading unit (200), a calibration unit (300) and an inspection unit (400) being installed on the top of the inspection seat (100) in sequence from left to right, characterized in that: The loading unit (200) comprises a wafer box (210) for loading wafers, and a transmitting device (220) and a sensing device (230) fixedly mounted on the detection seat (100) are respectively arranged on the left and right sides of the wafer box (210); The calibration unit (300) comprises a buffer vacuum plate (310) mounted on a detection seat (100); a motor for driving the buffer vacuum plate (310) to rotate is mounted at the bottom of the detection seat (100); and a flat edge positioning sensor (320), a center positioning sensor (330), a wafer backside visual inspection arm (340), a first exchange arm (350), and a pick-and-place arm (360) are mounted on the detection seat (100); The detection unit (400) comprises a second exchange arm (410) mounted on the detection base (100), a microscope (420) being mounted on the second exchange arm (410), and a vacuum stage (430) being mounted on the microscope (420); The transmitting device (220) comprises a fixed bracket (221), an adjusting bracket (222) and a signal amplifier (226) are mounted on the fixed bracket (221), a first laser transmitter (223) is fixedly mounted on the adjusting bracket (222), and the sensing device (230) comprises a first sensor (231) for receiving a signal from the first laser transmitter (223); The flat edge positioning sensor (320) comprises a second laser emitter (321) and a second sensor (322) for receiving an optical signal from the second laser emitter (321); the light emission path of the second laser emitter (321) is arranged obliquely to a placement plane at the top of the buffer vacuum plate (310); a concave mirror (323) is arranged at the bottom of the second sensor (322), wherein the concave mirror (323) is parallel to a signal receiving surface of the second sensor (322).

2. The microscope detection device with the function of positioning a transparent wafer according to claim 1, characterized in that: The number of the flat edge positioning sensor (320) is at least one, and the angle between the second laser emitter (321) and the placement plane of the top of the buffer vacuum plate (310) is sixty degrees.

3. The microscope detection device with the function of positioning a transparent wafer according to claim 1, characterized in that: A support seat (324) is fixedly mounted on the detection seat (100), the concave mirror (323) is fixedly mounted on the support seat (324), and the support seat (324) is in a C-shape.

4. The microscope detection device with the function of positioning a transparent wafer according to claim 1, characterized in that: The loading unit (200) comprises an electric lifting rod (240) fixedly mounted on the detection seat (100), a placement platform (250) fixedly mounted on the output end at the top of the electric lifting rod (240), and a maximum rising height of the placement platform (250) is greater than the highest height of the first laser emitter (223).

5. The microscope detection device with the function of positioning a transparent wafer according to claim 3, characterized in that: A constraint tube (325) is provided on one side of the concave mirror (323) facing the second laser emitter (321); the constraint tube (325) is located at the center of the concave mirror (323), and the constraint tube (325) is fixedly mounted on a support seat (324).

6. The microscope detection device with the function of positioning a transparent wafer according to claim 1, characterized in that: The adjusting bracket (222) is rotatably mounted on the fixing bracket (221) via a rotating shaft, a fastening screw (225) is threadedly connected to the fixing bracket (221), one end of the fastening screw (225) located inside the fixing bracket (221) is rotatably mounted with a contact block (224), and the other end of the contact block (224) is in contact with the rotating shaft of the adjusting bracket (222).

7. The microscope detection device with the function of positioning a transparent wafer according to claim 1, characterized in that: The first sensor (231) and the second sensor (322) both generate voltage measurements through photosensitive elements.

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