New device and method for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains

Abstract

The present invention discloses a new method for simultaneous quasi-equal optical path imaging confocal detection of adjacent surfaces of semiconductor crystal grains, wherein the detection device includes a camera, a telecentric imaging lens, a semi-transparent and semi-reflective image combiner, a semiconductor crystal grain and a transparent stage for holding the semiconductor crystal grain, which are sequentially arranged in the direction of the optical path. A first right-angle image rotation prism and a second right-angle image rotation prism are respectively arranged on the optical path between the semiconductor crystal grain and the semi-transparent and semi-reflective image combiner, the second right-angle image rotation prism is located on the first side of the optical axis of the telecentric imaging lens, and the two right-angle surfaces of the two right-angle image rotation prisms are both perpendicular to the optical path, and at least two surfaces of the semiconductor crystal grain are respectively imaged on different regional positions on the camera sensor surface through the right-angle image rotation prism and the semi-transparent and semi-reflective image combiner in a dual optical path. The present invention has the advantages that the detection of quasi-equal optical path confocal imaging and equal illumination illumination of adjacent surfaces of the crystal grain can be obtained; the distance △ between the double images of adjacent surfaces can be adjusted.

Description

Technical field:

[0002] The invention belongs to the field of optical detection and machine vision, and in particular relates to a new device and method for simultaneous quasi-equi-optical-path confocal imaging detection of adjacent surfaces of semiconductor grains. Background technology:

[0004] In machine vision imaging inspection applications, when the object to be inspected is large, a telecentric imaging lens with a suitable field of view is usually selected at a workstation to inspect one side of the object. When the object to be inspected is small (such as semiconductor optoelectronic components), in order to increase the inspection speed and make full use of the effective field of view of the telecentric imaging lens, a telecentric imaging lens at a workstation is used to simultaneously inspect two sides of the object.

[0005] The main technical problems that need to be solved by the device and method for simultaneous defect detection on adjacent surfaces of semiconductor grains include equal optical path imaging and equal illumination illumination of the double-sided detection light path.

[0006] The optical path difference of the double-sided imaging light path mainly depends on the following design and structural parameters of the system:

[0007] ① The distance between the double-sided image obtained on the image combiner / beam splitter is △=a+d (design parameter), where a is the object size and d is the minimum distance between the adjacent edges of the double-sided image of the object to satisfy the image recognition processing; when the object size a increases, △ also increases;

[0008] ② The horizontal (or vertical) distance from the center of the beam splitter / combiner to the center of the grain (structural parameter L1); in the optical path where the bottom and side surfaces are detected simultaneously, L1 is related to the size and △ of the object turntable.

[0009] ③ The vertical (or horizontal) distance between the center of the beam splitter / combiner and the inclined surface of the image transfer prism (structural parameter L2); in the simultaneous detection light path of the apex and the side, L2 is related to the size and △ of the object turntable.

[0010] In the solution proposed by the applicant's previous patent applications (patent application numbers 201910207016.2 and 201911247575.2), since the optical path difference △ of the dual-sided simultaneous imaging detection is related to the structural parameters (L1, L2), when the structural parameters are large, this method will inevitably have certain limitations in use; the above two applications use a larger right-angle image rotation prism and a large telecentric imaging lens to solve the resolution problem caused by the simultaneous detection of adjacent surfaces and their optical path difference, such as Figure 1a , as shown in 1b, and the recently filed patent application (application number 201911369253.5) also requires a larger right-angle image-transfer prism (such as 30×30×15) and a smaller image-transfer prism (such as 15x15×15) to be used on the adjacent two surfaces respectively. Figure 1cAs shown, however, in order to obtain equal optical path imaging detection, the relevant structural layout parameters need to be selected with particular care when designing the optical path, which limits the freedom of optical path design or increases the difficulty of implementing the detection system to a certain extent. Summary of the invention:

[0012] In response to the above-mentioned problems existing in adjacent surface detection, the present invention application proposes a new device and method for simultaneously detecting adjacent surfaces of semiconductor grains. The device and method adopt the structural principle of quasi-equal optical path confocal imaging of the detection light paths of the adjacent two surfaces at the combined image position, so that the optical path difference of the two-sided detection is more controllable and more practical.

[0013] The invention discloses a novel device for simultaneous quasi-equal optical path confocal imaging detection of adjacent surfaces of semiconductor crystal grains, characterized in that it comprises a camera, a telecentric imaging lens, a semi-transparent and semi-reflective image combiner, a semiconductor crystal grain, a transparent stage for holding the semiconductor crystal grain, and an illumination light source, which are sequentially arranged in the direction of the optical path; a first right-angle image rotation prism and a second right-angle image rotation prism are respectively arranged on the optical path between the semiconductor crystal grain and the semi-transparent and semi-reflective image combiner; the first right-angle image rotation prism and the second right-angle image rotation prism are located on the peripheral side of the semiconductor crystal grain; the first right-angle image rotation prism and the semi-transparent and semi-reflective image combiner are located on the optical axis of the telecentric imaging lens, and the semi-transparent and semi-reflective image combiner is arranged obliquely with the optical axis; the second right-angle image rotation prism is located on the first side of the optical axis of the telecentric imaging lens; the two right-angle surfaces of each of the two right-angle image rotation prisms are perpendicular to the optical path; and the two adjacent surfaces of the semiconductor crystal grain are imaged on different regional positions on the camera sensor surface via the right-angle image rotation prism and the semi-transparent and semi-reflective image combiner in a dual optical path.

[0014] Furthermore, the above-mentioned semi-transmissive and semi-reflective image combiner is replaced by a reflective and transmissive dual-zone image combiner.

[0015] Furthermore, the semi-transmissive and semi-reflective image combiner is replaced by a cubic beam splitter and image combiner.

[0016] Furthermore, the above device is provided with an illumination light source, which is a coaxial external light source located on the second side of the optical axis of the telecentric imaging lens; or the illumination light source is a coaxial built-in illumination light source built into the telecentric imaging lens.

[0017] Furthermore, the above device is provided with an illumination light source, which is located on the second side of the optical axis of the telecentric imaging lens, and on the side of the semiconductor crystal grain and below the transparent stage.

[0018] Furthermore, the first right-angle image rotation prism is located on one side of the semiconductor crystal, and the second right-angle image rotation prism is located above the top surface of the semiconductor crystal.

[0019] Furthermore, the first right-angle image rotation prism is located on one side of the semiconductor crystal grain, and the second right-angle image rotation prism is located below the transparent stage on the bottom surface of the semiconductor crystal grain.

[0020] The device and method of the present invention adopt the structural principle of quasi-equal optical path confocal (ie, very small △) imaging of the detection light paths of adjacent two surfaces at the combined image position, so that the optical path difference of the two-sided detection is more controllable and more practical.

[0021] The invention discloses a new method for simultaneous quasi-equal-optical-path confocal imaging detection of adjacent surfaces of semiconductor grains, characterized in that: the new device for simultaneous quasi-equal-optical-path confocal imaging detection of adjacent surfaces of semiconductor grains comprises a camera, a telecentric imaging lens, a semi-transparent and semi-reflective image combiner, a semiconductor grain and a transparent stage for holding the semiconductor grain, which are sequentially arranged in the direction of the optical path; a first right-angle image rotation prism and a second right-angle image rotation prism are respectively arranged on the optical path between the semiconductor grain and the semi-transparent and semi-reflective image combiner; the first right-angle image rotation prism and the second right-angle image rotation prism are located on the peripheral side of the semiconductor grain; the first right-angle image rotation prism and the semi-transparent and semi-reflective image combiner are located on the optical axis of the telecentric imaging lens, and the semi-transparent and semi-reflective image combiner is arranged obliquely with the optical axis; the second right-angle image rotation prism is located on the first side of the optical axis of the telecentric imaging lens; and the two right-angle surfaces of each of the two right-angle image rotation prisms are aligned with the optical axis of the telecentric imaging lens. The optical path is vertical, and at least two faces of the semiconductor crystal grain are imaged on different areas of the camera sensor surface by dual optical paths through a right-angle image rotation prism and a semi-transparent and semi-reflective image combiner. When working, the side face of the illuminated semiconductor crystal grain is imaged by 90 degrees through the two right-angle faces and the inclined face of the first right-angle image rotation prism, and then transmitted through the semi-transparent and semi-reflective image combiner, and imaged on the left half area of ​​the camera sensor surface by a telecentric imaging lens. For the top face or bottom face of the semiconductor crystal grain, after the 90 degrees image rotation of the two right-angle faces and the inclined face of the second right-angle image rotation prism, and then reflected by the semi-transparent and semi-reflective image combiner, it is imaged on the right half area of ​​the camera sensor surface by a telecentric imaging lens. The images of the side face and the top face or the bottom face of the semiconductor crystal grain are also obtained from the imaging surface of the camera at the same time, and there is a small gap between the image of the side face of the semiconductor crystal grain and the image of the top face or the bottom face of the semiconductor crystal grain.

[0022] Furthermore, the semi-transparent and semi-reflective image combiner is replaced by a reflective-transmissive dual-zone image combiner; when in operation, the side surface of the illuminated semiconductor grain is imaged by a 90-degree rotation through the two right-angle surfaces and the inclined surface of the first right-angle image rotation prism, and then is transmitted by the reflective-transmissive dual-zone image combiner, and is imaged on the left half area of ​​the camera sensor surface by a telecentric imaging lens; for the top or bottom surface of the semiconductor grain, it is imaged by a 90-degree rotation through the two right-angle surfaces and the inclined surface of the second right-angle image rotation prism, and then is reflected by the reflective-transmissive dual-zone image combiner, and is imaged on the right half area of ​​the camera sensor surface by a telecentric imaging lens; the images of the side surface and the top or bottom surface of the semiconductor grain are also obtained simultaneously on the imaging surface of the camera, and there is a small gap between the image of the side surface of the semiconductor grain and the image of the top or bottom surface of the semiconductor grain.

[0023] Furthermore, the semi-transparent and semi-reflective image combiner is replaced by a reflective and transmissive dual-zone image combiner; when working, the side surface of the illuminated semiconductor grain is imaged by a 90-degree rotation through the two right-angle surfaces and the inclined surface of the first right-angle image rotation prism, and then is transmitted through the cubic beam splitter, and is imaged on the left half area of ​​the camera sensor surface by the telecentric imaging lens; for the top or bottom surface of the semiconductor grain, it is imaged by a 90-degree rotation through the two right-angle surfaces and the inclined surface of the second right-angle image rotation prism, and then is reflected by the cubic beam splitter, and is imaged on the right half area of ​​the camera sensor surface by the telecentric imaging lens; the images of the side surface and the top or bottom surface of the semiconductor grain are also obtained simultaneously on the imaging surface of the camera, and there is a small gap between the image of the side surface of the semiconductor grain and the image of the top or bottom surface of the semiconductor grain.

[0024] Advantages of the new device for simultaneous equal-optical-path imaging detection of adjacent surfaces of semiconductor grains of the present invention:

[0025] ① It can obtain quasi-equal optical path confocal imaging of adjacent surfaces of grains and detection with equal illumination intensity;

[0026] ② Two sets of detection devices are used at two workstations respectively, which can realize the defect detection of four surfaces of grains and the detection of three dimensions;

[0027] ③The distance between the two images on adjacent surfaces can be adjusted;

[0028] ④ The design freedom of the working distance of the double-sided detection system is not restricted;

[0029] ⑤ The prism image transfer subsystem can be assembled in a sealed mechanical structure, with only two input windows for the test surface and one combined image output window exposed;

[0030] ⑥The mechanical assembly structure of the image-relay prism and the image combiner is simple, and assembly and debugging are easy;

[0031] ⑦The detection device has compact structure, small size and is easy to use;

[0032] ⑧The optical components used are all conventional products with small size, which has the advantage of low cost. Description of the drawings:

[0034] Figure 1a It is an existing optical device for detecting adjacent surfaces of grains;

[0035] Figure 1b It is an existing optical device for detecting adjacent surfaces of grains;

[0036] Figure 1c It is an existing optical device for detecting adjacent surfaces of grains;

[0037] Among them, B1 is camera, B2 is telecentric imaging lens, B3 is optical element, B4 is semiconductor crystal, B5 is transparent stage, B6 is right-angle rotation lens, and B7 is light source;

[0038] Figure 2a It is an optical device for sky and side detection (using coaxial external lighting and semi-transparent and semi-reflective image combiner);

[0039] Figure 2b It is an optical device for sky and side detection (using coaxial built-in illumination and reflection-transmission dual-zone image combiner);

[0040] Figure 3a It is an optical device for bottom and side inspection (using coaxial external lighting and semi-transparent and semi-reflective image combiner);

[0041] Figure 3b It is an optical device for bottom and side inspection (using coaxial built-in illumination and reflection-transmission dual-zone image combiner);

[0042] Figure 4 It is an optical device that uses backlighting for detection (in addition to using a coaxial external light source and a built-in light source, a backlight source is also provided for grain size detection);

[0043] Figure 5 It is an optical device for simultaneous detection of defects and sizes on four sides of a double-station grain;

[0044] Figure 6a It is a design embodiment of the prism image transfer subsystem of the sky and side detection optical device (using coaxial built-in illumination and reflection-transmission dual-zone image combiner);

[0045] Figure 6b It is a design embodiment of the prism image transfer subsystem of the sky and side detection optical device (using coaxial external illumination and semi-transparent and semi-reflective image combiner);

[0046] Figure 6c It is a design embodiment of the prism image transfer subsystem of the sky and side detection optical device (using coaxial external illumination and cubic beam splitter / combiner);

[0047] Among them, 7, 8, and 9 are external light sources;

[0048] Figure 7 It is a three-dimensional diagram of the mechanical assembly structure of the present invention from one viewing angle;

[0049] Figure 8 It is a three-dimensional diagram of the mechanical assembly structure of the present invention from another perspective;

[0050] Fig. 9 is an exploded view of the present invention;

[0051] Fig.10 yes Fig. 9 A partial view of

[0052] Fig.11 It is a three-dimensional diagram of the lower splint. Specific implementation method:

[0054] The new device for simultaneous quasi-equal optical path confocal imaging detection of adjacent surfaces of semiconductor grains of the present invention comprises a camera 1, a telecentric imaging lens 2, a semi-transparent and semi-reflective image combiner 3, a semiconductor grain 6 and a transparent stage 5 for holding the semiconductor grain, which are sequentially arranged in the direction of the optical path. A first right-angle image rotation prism 4b and a second right-angle image rotation prism 4a are respectively arranged on the optical path between the semiconductor grain 6 and the semi-transparent and semi-reflective image combiner 3. The first right-angle image rotation prism 4b and the second right-angle image rotation prism 4a are located on the peripheral side of the semiconductor grain 6. The first right-angle image rotation prism 4b and the semi-transparent and semi-reflective image combiner 3 are located on the optical axis A of the telecentric imaging lens 2, and the semi-transparent and semi-reflective image combiner 3 is inclined to the optical axis A. The second right-angle image rotation prism 4a is located on the first side A1 of the optical axis of the telecentric imaging lens. The two right-angle surfaces of each of the two right-angle image rotation prisms are perpendicular to the optical path. The two adjacent surfaces of the semiconductor grain are imaged on different regional positions on the camera sensor surface through the right-angle image rotation prism and the semi-transparent and semi-reflective image combiner in a dual optical path.

[0055] The above embodiment Figure 2a , 3a As shown, Figure 2a For the inspection of the top and side surfaces of semiconductor chips, Figure 3a It is used to detect the bottom and side surfaces of semiconductor crystals, distinguishing them based on their positional relationship. Figure 3a So Figure 2a The center of the semiconductor crystal grain is the center of the circle, and the components except the semiconductor crystal grain 6 and the transparent stage 5 are rotated 180 degrees.

[0056] In another embodiment, the semi-transmissive and semi-reflective image combiner 3 can be replaced by a reflective and transmissive dual-zone image combiner 3a, such as Figure 2b , 3b As shown; Figure 2b and 3b The difference is also Figure 3a and Figure 2a The difference.

[0057] In another embodiment, the semi-transmissive and semi-reflective image combiner 3 can be replaced by a cubic beam splitter 3b.

[0058] The semi-transmissive and semi-reflective image combiner 3, the reflective and transmissive dual-zone image combiner 3a or the cubic beam splitter 3b acts as a beam splitter in the illumination optical path and acts as an image combiner in the imaging optical path.

[0059] The semi-transmissive and semi-reflective image combiner 3 is a common optical device, which is formed by coating a splitter film with a transmission and reflection ratio of 50%:50% on one side of a flat plate; similarly, the cubic beam splitter 3b is also a common optical device, which can be coated with a splitter film with a transmission and reflection ratio of 50%:50% on the inclined surface of a right-angle prism, and the inclined surfaces of two right-angle reflecting prisms are glued together; the reflective and transmissive dual-zone image combiner 3a is formed by coating half of the area on a flat glass with a high-reflective film and the other half with an anti-reflection film.

[0060] Above Figure 2a The figure shows an optical device for simultaneously inspecting the top and side surfaces of semiconductor crystal grains, wherein the semi-transparent and semi-reflective image combiner acts as a beam splitter in the illumination optical path and acts as an image combiner in the imaging optical path; Figure 2b Corresponding to the detection optical device using a reflection-transmission dual-zone image combiner and a coaxial built-in illumination light source, the imaging detection light paths of the top and side surfaces of the detection optical device are exactly the same, achieving simultaneous double-sided detection with completely equal optical path imaging and equal illumination.

[0061] Similarly, the detection light paths of the bottom and side surfaces of the semiconductor crystal grain can also be exactly the same. It is only necessary to appropriately select the size of the right-angle image-turning prism in the side light path to compensate for the thickness of the glass turntable (transparent stage) in the bottom light path.

[0062] Figure 2a The illumination source of the crystal grain shown is located on the right side of the semi-transparent and semi-reflective image combiner, which is a coaxial external illumination. When a half-reflective + half-transmissive dual-zone image combiner is used ( Figure 2b As shown in the figure, the illumination of the grains uses a built-in coaxial lighting source. At this time, the images of the side and top (or bottom) are located on both sides of the boundary between the reflection area and the transmission area of ​​the image combiner. The size detection of semiconductor grains requires a high-contrast contour, and usually uses a different lighting method from the grain surface defect detection, such as backlighting.

[0063] like Figure 3a, 3b are optical devices for simultaneous detection of the bottom and side surfaces of coaxial external illumination and coaxial internal illumination, respectively. In the above-mentioned new device for simultaneous detection of adjacent surfaces of semiconductor grains, the quasi-equal optical path structure principle of the detection light paths of adjacent double surfaces at the combined image position is adopted. A simple analysis and calculation of the optical path difference of the adjacent double-sided detection light paths can show that the double-sided detection optical path difference has nothing to do with the structural parameters L1 and L2, but is only related to the design parameter △ of the distance between adjacent double-sided images (△=a+d), that is, it is only related to the semiconductor grain size a and the design parameter d, where a is the object size, and d is the minimum distance between the adjacent edges of the double-sided images of the object to meet the image recognition processing. When the grain size a and the double-image distance d are small (usually a≤1~2mm, d≈1~2mm), the double-sided detection optical path difference △ is also small, and this small optical path difference △ can be compensated by selecting a telecentric imaging lens with an appropriate depth of field, so it is identified as a quasi-equal optical path confocal imaging detection device. This important structural feature can make the optical path difference of double-sided detection more controllable and the detection system more practical.

[0064] The adjacent surface detection device proposed in this patent application can obtain equal optical path imaging and equal illumination detection of the top and side surfaces of the grain. For the detection of the bottom and top surfaces, by appropriately compensating for the optical path and illumination loss of the glass stage (transparent stage), equal optical path imaging and equal illumination detection can also be achieved.

[0065] This detection device can use the backlighting method to realize the size detection of high-contrast contour imaging of the top (or bottom) and side surfaces of the grain, such as Figure 4 As shown, a cubic beam splitter is used here (it acts as a beam splitter in the illumination light path and as an image combiner in the imaging light path) to facilitate the optical assembly and debugging of the front-end image transfer subsystem of the adjacent surface imaging detection device.

[0066] Two sets of detection devices are installed on the two workstations, namely the top and right side, and the bottom and left side, to achieve simultaneous detection of defects on the four sides of the grain and simultaneous detection of the three sizes of the grain, such as Figure 5 As shown, a cubic beam splitter is also used here to facilitate the optical assembly and debugging of the front-end image transfer subsystem of the adjacent surface imaging detection device.

[0067] The present invention discloses a new method for simultaneous quasi-equal-optical-path confocal imaging detection of adjacent surfaces of semiconductor crystal grains. The new device for simultaneous quasi-equal-optical-path confocal imaging detection of adjacent surfaces of semiconductor crystal grains comprises a camera, a telecentric imaging lens, a semi-transparent and semi-reflective image combiner, a semiconductor crystal grain and a transparent stage for holding the semiconductor crystal grain, which are sequentially arranged in the direction of the optical path. A first right-angle image rotation prism and a second right-angle image rotation prism are respectively arranged on the optical path between the semiconductor crystal grain and the semi-transparent and semi-reflective image combiner. The first right-angle image rotation prism and the second right-angle image rotation prism are located on the peripheral side of the semiconductor crystal grain. The first right-angle image rotation prism and the semi-transparent and semi-reflective image combiner are located on the optical axis of the telecentric imaging lens, and the semi-transparent and semi-reflective image combiner is arranged obliquely with the optical axis. The second right-angle image rotation prism is located on the first side of the optical axis of the telecentric imaging lens. The two right-angle surfaces of each of the two right-angle image rotation prisms are perpendicular to the optical path. At least two faces of the semiconductor crystal grain are respectively imaged on different areas of the camera sensor surface by a right-angle image-turning prism and a semi-transparent and semi-reflective image combiner with dual optical paths; when working, the side face of the illuminated semiconductor crystal grain is imaged by a 90-degree image-turning of the two right-angle faces and the oblique face of the first right-angle image-turning prism, and then is transmitted by the semi-transparent and semi-reflective image combiner, and is imaged on the left half area of ​​the camera sensor surface by a telecentric imaging lens; for the top face or bottom face of the semiconductor crystal grain, after the 90-degree image-turning of the two right-angle faces and the oblique face of the second right-angle image-turning prism, and then is reflected by the semi-transparent and semi-reflective image combiner, it is imaged on the right half area of ​​the camera sensor surface by a telecentric imaging lens; the side face and top face or bottom face images of the semiconductor crystal grain are also obtained from the imaging surface of the camera at the same time, and the image of the side face of the semiconductor crystal grain is separated from the image of the top face or bottom face of the semiconductor crystal grain by a small distance (such as Figure 2a , 3a ).

[0068] Furthermore, the semi-transparent and semi-reflective image combiner is replaced by a reflective-transmissive dual-zone image combiner; when working, the side surface of the illuminated semiconductor crystal grain is imaged by the 90-degree image rotation of the two right-angle surfaces and the inclined surface of the first right-angle image rotation prism, and then is transmitted by the reflective-transmissive dual-zone image combiner, and is imaged on the left half area of ​​the camera sensor surface by the telecentric imaging lens; for the top or bottom surface of the semiconductor crystal grain, after the 90-degree image rotation of the two right-angle surfaces and the inclined surface of the second right-angle image rotation prism, it is reflected by the reflective-transmissive dual-zone image combiner and is imaged on the right half area of ​​the camera sensor surface by the telecentric imaging lens; the images of the side surface and the top or bottom surface of the semiconductor crystal grain are also obtained from the imaging surface of the camera at the same time, and there is a small spacing (such as 1 / 4") between the image of the side surface of the semiconductor crystal grain and the image of the top or bottom surface of the semiconductor crystal grain. Figure 2b , 3b ).

[0069] Furthermore, the semi-transparent and semi-reflective image combiner is replaced by a reflective and transmissive dual-zone image combiner; when working, the side surface of the illuminated semiconductor crystal grain is imaged by the 90-degree image rotation of the two right-angle surfaces and the inclined surface of the first right-angle image rotation prism, and then is transmitted by the cubic beam splitter, and is imaged on the left half area of ​​the camera sensor surface by the telecentric imaging lens; for the top surface or bottom surface of the semiconductor crystal grain, it is imaged by the 90-degree image rotation of the two right-angle surfaces and the inclined surface of the second right-angle image rotation prism, and then is reflected by the cubic beam splitter, and is imaged on the right half area of ​​the camera sensor surface by the telecentric imaging lens; the images of the side surface and the top surface or bottom surface of the semiconductor crystal grain are also obtained from the imaging surface of the camera at the same time, and the image of the side surface of the semiconductor crystal grain is separated from the image of the top surface or bottom surface of the semiconductor crystal grain by a small distance (such as Figure 4 , 5 ).

[0070] Embodiments of the adjacent surface detection optical device of the present application:

[0071] 1. Embodiment of the prism image transfer subsystem at the front end of the detection device, Figure 6a , 6b, 6C are design embodiments of the prism image transfer subsystem of the optical device for simultaneous detection of the sky and the side, wherein the optical element 3 can be a semi-transparent and semi-reflective image combiner, a reflective and transmissive dual-zone image combiner or a cubic beam splitter, or can be named a semi-transparent and semi-reflective beam splitter / image combiner, a reflective and transmissive dual-zone beam splitter / image combiner, a cubic beam splitter / image combiner, and its light source can be a coaxial internal and external lighting light source as needed.

[0072] When making specific

[0073] ① The working distance from the crystal to the telecentric imaging lens is 65mm.

[0074] ② The cross-section of the two right-angle image-transfer prisms is a right-angled triangular column with a length, width and height of 15×15x15mm;

[0075] ③ The reflective-transmissive dual-zone beam splitter / combiner or the semi-transmissive-semi-reflective beam splitter / combiner is a rectangular plate with a size of 18×15x1mm, and the cubic beam splitter / combiner is a cube with a size of 15x15×15mm;

[0076] ④ The glass turntable (transparent stage) is 45mm long and 6mm thick;

[0077] ⑤Top optical path: The distance from the top of the glass turntable to the right-angle surface of the second right-angle image-turning prism just above or just below the grain is 7.35 mm.

[0078] ⑥Side optical path: The distance from the edge of the glass turntable to the right-angle surface of the first right-angle image-turning prism on the side is 7.5mm.

[0079] ⑦ According to needs, the distance between the centers of adjacent facial images is taken as △=3.0~3.5mm.

[0080] ⑧The distance between the horizontal light path on the side of the grain and the horizontal light path on the sky after turning 90 degrees is 14.2mm.

[0081] 2. Method for adjusting the distance between adjacent double images

[0082] ① When the position of the semi-transparent and semi-reflective image combiner is fixed, if the position of the first right-angle image-turning prism in the side light path is kept unchanged, the position of the second right-angle image-turning prism in the sky light path can be adjusted in the vertical (or horizontal) direction to change the distance △ between the sky image and the optical axis.

[0083] ② On the contrary, if the position of the second right-angle image-turning prism 4a in the sky light path is kept unchanged, the position of the first right-angle image-turning prism 4b in the side light path can be adjusted horizontally (or vertically), the distance △ between the side image and the optical axis can also be changed.

[0084] ③ Or fine-tune the first and second right-angle image-turning prisms in the vertical and horizontal directions at the same time to achieve a change in the distance △ between the double images on adjacent surfaces.

[0085] 3. Double-sided detection optical path working distance adjustment method

[0086] ① When the second right-angle image rotation prism 4a and the image combiner move up and down in the vertical direction as a whole, the working distance from the right-angle surface of the zenith detection light path to the zenith of the grain can be adjusted.

[0087] ② When the first right-angle image rotation prism 4b and the image combiner move horizontally left and right as a whole, the working distance from the right-angle surface of the side detection light path to the side surface of the grain (or the edge of the glass object carrier turntable) can be adjusted.

[0088] The above device is provided with an illumination light source, which is located at the second side A2 of the optical axis of the telecentric imaging lens, and at the side of the semiconductor die and below the transparent stage, and the first side A1 and the second side A2 of the optical axis of the telecentric imaging lens are opposite to each other with respect to the optical axis A of the telecentric imaging lens (such as Figure 2a , 2b , 3a, 3b, 4 and 5).

[0089] One implementation example is Figure 2a , 2b The first right-angle image rotation prism 4b is located on one side of the semiconductor crystal grain, and the second right-angle image rotation prism 4a is located above the zenith of the semiconductor crystal grain.

[0090] Another implementation such as Figure 3a , 3b The first right-angle image rotation prism is located on one side of the semiconductor crystal grain, and the second right-angle image rotation prism is located below the transparent stage on the bottom surface of the semiconductor crystal grain.

[0091] Advantages of the new device for simultaneous equal-optical-path imaging detection of adjacent surfaces of semiconductor grains of the present invention:

[0092] ① It can obtain equal optical path imaging and equal illumination detection of adjacent surfaces of grains;

[0093] ② Two sets of detection devices are used at two workstations respectively, which can realize the defect detection of four surfaces of grains and the detection of three dimensions;

[0094] ③The distance between the two images on adjacent surfaces can be adjusted;

[0095] ④ The design freedom of the working distance of the double-sided detection system is not restricted;

[0096] ⑤ The prism image transfer subsystem can be assembled in a sealed mechanical structure, with only two input windows for the test surface and one combined image output window exposed;

[0097] ⑥The mechanical assembly structure of the image-relay prism and the image combiner is simple, and assembly and debugging are easy;

[0098] ⑦The detection device has compact structure, small size and is easy to use;

[0099] ⑧The optical components used are all conventional products with small size, which has the advantage of low cost.

[0100] In addition, for Figure 4 In an embodiment, the present application further proposes a mechanical assembly structure of a semiconductor grain adjacent surface detection pre-image-reversing prism system, which includes an upper clamping plate M1 and a lower clamping plate M2 arranged in parallel and opposite to each other, a first right-angle image-reversing prism M3, a second right-angle image-reversing prism M4 and a cubic beam splitter M5 clamped between the upper and lower clamping plates, a first positioning member M6 and a second positioning member M7 for limiting the first right-angle image-reversing prism M3, the second right-angle image-reversing prism M4 and the cubic beam splitter M5 are respectively provided on opposite surfaces of the upper clamping plate M1 and the lower clamping plate M2, a first right-angle surface M8 of the first right-angle image-reversing prism is close to or in contact with a first side surface M9 of the cubic beam splitter M5, and a first right-angle surface M10 of the second right-angle image-reversing prism M4 is opposite to a second side surface M11 of the cubic beam splitter.

[0101] The upper clamping plate M1 and the lower clamping plate M2 can be made of metal or plastic materials, the first right-angle image rotation prism M3, the second right-angle image rotation prism M4 and the cubic beam splitter M5 are made of optical materials that meet the design requirements, and the structures of the upper clamping plate M1 and the lower clamping plate M2 are symmetrically arranged; wherein M is the crystal grain to be measured, the first right-angle image rotation prism M3, the second right-angle image rotation prism M4 and the cubic beam splitter M5, the crystal grain to be measured M and Figure 4 Different numbers are used.

[0102] In the present application, the first right-angle image-reversing prism M3, the second right-angle image-reversing prism M4 and the cubic beam splitter M5 form a pre-image-reversing prism subsystem, which together with the imaging lens constitutes a grain imaging detection optical system.

[0103] Furthermore, in order to meet assembly requirements, the upper and lower clamping plates are both in a curved shape, including a transverse plate M12 and a longitudinal plate M13, wherein the first positioning member M6 is disposed on the transverse plate M12, and the second positioning member M7 is disposed on the longitudinal plate M13.

[0104] Furthermore, the first positioning member M6 includes a first elongated boss M14 provided on the edge of the transverse plate surface of the splint; the second positioning member includes a second elongated boss M15 provided on the edge of the longitudinal plate surface, the second elongated boss M15 and the first elongated boss M14 are perpendicular to each other, and an inclined boss M16 whose hypotenuse is at an angle of 45 degrees to the second elongated boss is provided on the longitudinal plate surface next to the second elongated boss. When in use, the second right-angle image-turning prism M4 is abutted against the edge of the first elongated boss M14 and can be adjusted left and right, and the first right-angle image-turning prism M3 is placed between the second elongated boss M15 and the inclined boss M16. The relative position of the first right-angle image-turning prism M3 and the cubic beam splitter M5 can be adjusted in advance and bonded and fixed, so that after the first right-angle image-turning prism M3 is positioned between the second elongated boss M15 and the inclined boss M16, the cubic beam splitter M5 is also located at the correct position.

[0105] Furthermore, in order to clamp and fix, the upper and lower clamping plates are relatively provided with a plurality of hole grooves M17 for bolts to pass through and fix. By passing bolts through the hole grooves M17 on the upper and lower clamping plates, the upper and lower clamping plates and the first right-angle image rotation prism M3, the second right-angle image rotation prism M4 and the cubic beam splitter M5 therein are fixed.

[0106] Furthermore, the above-mentioned cubic beam splitter is a cube formed by the inclined surfaces of two right-angle image-turning prisms that are relatively close to each other, and has a half-transmitting and half-reflecting surface on the inclined surface, that is, the half-transmitting and half-reflecting surface can be realized by a film layer or a coating, and the two acute angles of the first right-angle image-turning prism are cut off, and one acute angle of the second right-angle image-turning prism is cut off.

[0107] Furthermore, in order to avoid bumps, two enclosures are fixed between the upper and lower clamping plates, namely the first enclosure M18 and the second enclosure M19. The first enclosure M18 and the second enclosure M19 are respectively formed by three sections of opaque plates that are sequentially bent at 90 degrees. Windows for light paths to pass through are respectively provided on the two sides of the three sections of plates. The first enclosure M18 and the second enclosure M19 can be formed by stamping stainless steel plates, thereby playing a role in protecting and preventing optical elements from bumps.

[0108] Furthermore, a window M22 of the first enclosure corresponds to the third side surface M20 of the cubic beam splitter, and another window M23 of the first enclosure corresponds to the second right-angle surface M21 of the second right-angle image-turning prism; a window M24 of the second enclosure corresponds to the second right-angle surface M26 of the first right-angle image-turning prism, and another window M25 of the second enclosure corresponds to the fourth side surface M27 of the cubic beam splitter, and the above-mentioned passages are all for satisfying the passage of the light path in the light path.

[0109] Advantages of the mechanical assembly structure of the semiconductor grain adjacent surface detection front image transfer prism system:

[0110] ① There is only one second right-angle image-turning prism, a cubic beam splitter and two optical components formed by the first right-angle image-turning prism. The mechanical assembly structure is simple and easy to assemble and debug;

[0111] ② The distance between the two images on adjacent surfaces can be slightly adjusted by moving the right-angle image-turning prism left and right in the horizontal direction;

[0112] ③Except for the exposed windows, all optical components are sealed and assembled in the mechanical structure, which effectively ensures the precision of the mechanical structure positioning, and the support and assembly are firm and reliable.

[0113] ④The detection device has a compact mechanical structure, small size and is easy to use.

[0114] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A new device for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains, characterized in that: The invention comprises a camera, a telecentric imaging lens, a semi-transparent and semi-reflective image combiner, a semiconductor crystal grain and a transparent stage for holding the semiconductor crystal grain, which are sequentially arranged in the direction of the optical path. A first right-angle image rotation prism and a second right-angle image rotation prism are respectively arranged on the optical path between the semiconductor crystal grain and the semi-transparent and semi-reflective image combiner. The first right-angle image rotation prism and the second right-angle image rotation prism are located on the peripheral side of the semiconductor crystal grain. The first right-angle image rotation prism and the semi-transparent and semi-reflective image combiner are located on the optical axis of the telecentric imaging lens, and the semi-transparent and semi-reflective image combiner are arranged obliquely with the optical axis. The second right-angle image rotation prism is located on the first side of the optical axis of the telecentric imaging lens. The two right-angle surfaces of the two right-angle image rotation prisms are both perpendicular to the optical path. Two adjacent surfaces of the semiconductor crystal grain are imaged on different regional positions on the camera sensor surface through the right-angle image rotation prism and the semi-transparent and semi-reflective image combiner in a dual optical path.

2. According to the new device for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains as described in claim 1, it is characterized by: The semi-transmissive and semi-reflective image combiner is replaced by a reflective-transmissive dual-zone image combiner.

3. The new device for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains according to claim 1, characterized in that: The semi-transmissive and semi-reflective image combiner is replaced by a cubic beam splitter.

4. The new device for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains according to claim 1 or 2, characterized in that: The device is provided with an illumination light source, which is a coaxial external illumination light source located outside the telecentric imaging lens; or the illumination light source is a coaxial internal illumination light source built into the telecentric imaging lens.

5. The new device for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains according to claim 3 is characterized in that: The device is provided with an illumination light source and a backlight illumination light source, wherein the coaxial external illumination light source is located at the second side of the optical axis of the telecentric imaging lens, and the backlight illumination light source is located at the side of the semiconductor crystal grain and below the transparent stage.

6. The new device for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains according to claim 1, characterized in that: The first right-angle image-turning prism is located on one side of the semiconductor crystal grain, and the second right-angle image-turning prism is located above the top surface of the semiconductor crystal grain.

7. The new device for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains according to claim 1, characterized in that: The first right-angle image-turning prism is located on one side of the semiconductor crystal grain, and the second right-angle image-turning prism is located below the transparent stage on the bottom surface of the semiconductor crystal grain.

8. A new method for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains, characterized in that: The novel device for simultaneous quasi-equal optical path confocal imaging detection of adjacent surfaces of semiconductor crystal grains comprises a camera, a telecentric imaging lens, a semi-transparent and semi-reflective image combiner, a semiconductor crystal grain and a transparent stage for holding the semiconductor crystal grain, which are sequentially arranged in the direction of the optical path; a first right-angle image rotation prism and a second right-angle image rotation prism are respectively arranged on the optical path between the semiconductor crystal grain and the semi-transparent and semi-reflective image combiner; the first right-angle image rotation prism and the second right-angle image rotation prism are located on the peripheral side of the semiconductor crystal grain; the first right-angle image rotation prism and the semi-transparent and semi-reflective image combiner are located on the optical axis of the telecentric imaging lens, and the semi-transparent and semi-reflective image combiner is arranged obliquely with the optical axis; the second right-angle image rotation prism is located on the first side of the optical axis of the telecentric imaging lens; the two right-angle surfaces of each of the two right-angle image rotation prisms are perpendicular to the optical path; at least two surfaces of the semiconductor crystal grain are divided into The semiconductor crystal grains are imaged on different areas of the camera sensor surface with dual optical paths through right-angle image-turning prisms and semi-transparent and semi-reflective image combiners. When working, the side surface of the illuminated semiconductor crystal grain is imaged on the left half area of ​​the camera sensor surface through 90-degree image rotation through the two right-angle surfaces and the inclined surface of the first right-angle image-turning prism, and then transmitted through the semi-transparent and semi-reflective image combiner, and imaged on the right half area of ​​the camera sensor surface by the telecentric imaging lens. For the top surface or bottom surface of the semiconductor crystal grain, the image is imaged on the right half area of ​​the camera sensor surface through 90-degree image rotation through the two right-angle surfaces and the inclined surface of the second right-angle image-turning prism, and then reflected by the semi-transparent and semi-reflective image combiner, and imaged on the right half area of ​​the camera sensor surface by the telecentric imaging lens. The images of the side surface and the top surface or bottom surface of the semiconductor crystal grain are also obtained from the imaging surface of the camera at the same time, and there is a small gap between the image of the side surface of the semiconductor crystal grain and the image of the top surface or bottom surface of the semiconductor crystal grain.

9. The novel method for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains according to claim 8, characterized in that: The semi-transparent and semi-reflective image combiner is replaced by a reflective-transmissive dual-zone image combiner; when working, the side surface of the illuminated semiconductor crystal grain is imaged by a 90-degree rotation through the two right-angle surfaces and the inclined surface of the first right-angle image rotation prism, and then is transmitted by the reflective-transmissive dual-zone image combiner, and is imaged on the left half area of ​​the camera sensor surface by a telecentric imaging lens; for the top surface or bottom surface of the semiconductor crystal grain, it is imaged by a 90-degree rotation through the two right-angle surfaces and the inclined surface of the second right-angle image rotation prism, and then is reflected by the reflective-transmissive dual-zone image combiner, and is imaged on the right half area of ​​the camera sensor surface by a telecentric imaging lens; the images of the side surface and the top surface or the bottom surface of the semiconductor crystal grain are also obtained from the imaging surface of the camera at the same time, and there is a small gap between the image of the side surface of the semiconductor crystal grain and the image of the top surface or the bottom surface of the semiconductor crystal grain.

10. The novel method for simultaneous quasi-equi-optical confocal imaging detection of adjacent surfaces of semiconductor grains according to claim 8, characterized in that: The semi-transparent and semi-reflective image combiner is replaced by a reflective and transmissive dual-zone image combiner; when working, the side surface of the illuminated semiconductor crystal grain is imaged by a 90-degree rotation through the two right-angle surfaces and the inclined surface of the first right-angle image rotation prism, and then is transmitted by the cubic beam splitter, and is imaged on the left half area of ​​the camera sensor surface by a telecentric imaging lens; for the top surface or bottom surface of the semiconductor crystal grain, it is imaged by a 90-degree rotation through the two right-angle surfaces and the inclined surface of the second right-angle image rotation prism, and then is reflected by the cubic beam splitter, and is imaged on the right half area of ​​the camera sensor surface by a telecentric imaging lens; the images of the side surface and the top surface or bottom surface of the semiconductor crystal grain are also obtained from the imaging surface of the camera at the same time, and there is a small gap between the image of the side surface of the semiconductor crystal grain and the image of the top surface or bottom surface of the semiconductor crystal grain.

Images