Optical detection device

Abstract

The utility model relates to an optical detection device. The optical detection device comprises an imaging module; the light source module is used for providing illumination light for the detected element; the multiple groups of reflection assemblies are all arranged in the field of view of the imaging module, and each reflection assembly is used for reflecting light from at least two surfaces of the corresponding detected element to the imaging module; the imaging module is used for at least receiving reflected light rays from the multiple groups of reflection assemblies so as to carry out imaging on the multiple detected elements. The multiple groups of reflection assemblies are arranged in the view field of the imaging module, the light rays from at least two surfaces of the corresponding detected elements are reflected to the imaging module, the imaging module at least receives the reflection light rays from the multiple groups of reflection assemblies so as to image the multiple detected elements, multi-surface detection can be carried out on the multiple detected elements at the same time, and the detection efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor detection, in particular to an optical detection device. BACKGROUND

[0002] With the upgrading of semiconductor packaging materials and processes, there are more and more chip packages with smaller volume and higher integration, and consumers have higher and higher requirements for the appearance, size position accuracy and physical performance of the chip packages. Therefore, appearance detection of chip products is an essential step. Among them, the detection items such as defects and thickness of the side surface of the chip have always been the difficulty of appearance detection of chip products.

[0003] The traditional optical detection equipment uses a light source to provide imaging illumination conditions, needs to use a material taking mechanism to rotate the chip multiple times, and then uses a control imaging device to image multiple times to obtain images of each surface of the chip, so as to complete the detection of one chip. The detection efficiency is low because of the time-consuming. CONTENT OF THE INVENTION

[0004] Therefore, it is necessary to provide an optical detection device capable of improving detection efficiency in view of the above problems.

[0005] An optical detection device comprises:

[0006] an imaging module;

[0007] a light source module configured to provide illumination light for a measured element;

[0008] a plurality of reflection assemblies, each of which is arranged in a field of view of the imaging module, and each of the reflection assemblies is configured to reflect light from at least two surfaces of a corresponding measured element to the imaging module;

[0009] The imaging module is configured to receive reflected light from the plurality of reflection assemblies to image a plurality of measured elements.

[0010] In one embodiment, the reflection assembly comprises a plurality of reflection prisms, and the plurality of reflection prisms surround a detection position for placing a measured element.

[0011] In one embodiment, part of the illumination light emitted by the light source module is reflected to a plurality of side surfaces of a corresponding measured element through the plurality of reflection prisms, and the reflection prisms reflect first imaging light from the plurality of side surfaces of the corresponding measured element to the imaging module.

[0012] Part of the illumination light emitted by the light source module is incident on the front surface or the back surface of the measured element and forms second imaging light by reflection or scattering to the imaging module.

[0013] The imaging module receives the first and second imaging lights to simultaneously image multiple sides of the measured element and the front or back surface of the measured element.

[0014] In one embodiment, the reflection prisms include first and second reflection prisms, the first reflection prisms are arranged around the second reflection prisms to form at least two detection positions.

[0015] In one embodiment, the first and second reflection prisms are isosceles right-angle prisms.

[0016] One of the right-angle sides of the first reflection prisms is arranged in parallel to the optical axis of the imaging module, and the hypotenuse of each of the first reflection prisms reflects the illumination light from the light source module to the side surface of the corresponding measured element and reflects the light from the side surface of the corresponding measured element to the imaging module to image the multiple side surfaces of the measured element.

[0017] The hypotenuse of the second reflection prisms is arranged perpendicularly to the optical axis of the imaging module, and the two right-angle sides of the second reflection prisms reflect the illumination light from the light source module to the side surface of the corresponding measured element and reflect the light from the side surface of the corresponding measured element to the imaging module to image the multiple side surfaces of the measured element.

[0018] In one embodiment, the reflection assembly further includes a mounting module connecting the reflection prisms, the mounting module is used to mount the reflection prisms and adjust the relative positions between the reflection prisms to adapt to measured elements of different sizes.

[0019] In one embodiment, the imaging module includes a camera and an object-side telecentric lens, and the field of view of the object-side telecentric lens corresponds to multiple sets of the reflection assembly.

[0020] In one embodiment, the light source module includes a ring-shaped light source providing dark-field illumination light and / or a coaxial light source providing bright-field illumination light.

[0021] In one embodiment, the ring-shaped light source and / or the coaxial light source are light sources capable of providing illumination light of multiple wavelengths.

[0022] In one embodiment, the optical detection device further includes a filter arranged between the imaging module and the light source module.

[0023] The aforementioned optical inspection device, by setting multiple sets of reflective components within the field of view of the imaging module, reflects light from at least two sides of the corresponding test element to the imaging module. The imaging module receives the reflected light from at least multiple sets of reflective components to image multiple test elements, thereby enabling multi-faceted inspection of multiple test elements simultaneously and improving inspection efficiency. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the optical detection device in one embodiment;

[0025] Figure 2 This is a schematic diagram of the structure of a reflective component in one embodiment;

[0026] Figures 3 to 5 This is a schematic diagram illustrating the adjustment of the relative positions between the reflecting prisms in one embodiment;

[0027] Figure 6 This is a schematic diagram of the optical detection device in one embodiment;

[0028] Figure 7 This is a schematic diagram of the optical detection device in another embodiment;

[0029] Figure 8 This is a schematic diagram showing the positional relationship between the reflective component and the element under test in one embodiment;

[0030] Figure 9 This is a schematic diagram showing the positional relationship between the reflective component and the element under test in another embodiment;

[0031] Figure 10 This is a three-dimensional structural diagram of the reflective component in one embodiment;

[0032] Figure 11 A three-dimensional structural diagram of the reflective component in another embodiment;

[0033] Figure 12 This is a schematic diagram of the imaging module in one embodiment. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0036] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0037] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, operations, components, parts, or combinations thereof.

[0038] In one embodiment, such as Figure 1 The invention provides an optical inspection device, comprising multiple sets of reflective components 10, a light source module 20, and an imaging module 30. The light source module 20 is used to provide illumination light to the device under test 300. The multiple sets of reflective components 10 are all disposed within the field of view of the imaging module 30, and each reflective component 10 is used to reflect light from at least two sides of the corresponding device under test 300 to the imaging module 30. The imaging module 30 is used to receive at least the reflected light from the multiple sets of reflective components 10 to image the multiple devices under test 300.

[0039] Specifically, the device under test (DUT) 300 can be a semiconductor chip or other devices requiring surface appearance inspection. Taking semiconductor chip inspection as an example, the chip cross-section can be square or rectangular, or other similar chip structures, including a chip side inspection structure where two square chips are connected together by a communication line. Common chip packages include BGA, QFN, FLP, LEAD, and other similar packages. Part of the illumination light output from the light source module 20 directly illuminates the DUT 300, and part is reflected by the reflector 10 to various sides of the DUT 300. The reflector 10 reflects the light from the respective sides of the DUT 300. The reflected light can be transmitted to the imaging module 30 after passing through the light source module 20, or it can be directly transmitted to the imaging module 30.

[0040] The specific structure of the reflective component 10 is not unique; it can be a selection of reflective prisms and / or mirrors for light reflection. In one embodiment, the reflective component 10 includes multiple reflective prisms arranged around a detection position formed for placing the element under test 300. Furthermore, the optical inspection device may also include a mechanical gripper 400, which moves the element under test 300 to the detection position for inspection.

[0041] The part of the illumination light emitted by the light source module 20 is reflected by the plurality of reflecting prisms to the plurality of side surfaces of the corresponding measured element 300, and the reflecting prisms reflect the first imaging light from the plurality of side surfaces of the corresponding measured element 300 to the imaging module 30. The part of the illumination light emitted by the light source module 20 is incident to the front surface or the back surface of the measured element 300, and is reflected or scattered to form the second imaging light to the imaging module 30. The imaging module 30 receives the first imaging light and the second imaging light to simultaneously image the plurality of side surfaces of the measured element 300 and the front surface or the back surface of the measured element 300. The side surfaces and the front surface (or the back surface) of each measured element 300 can be simultaneously imaged, and when the measured element 300 is a rectangular chip, the four side surfaces and the front surface (or the back surface) of each chip are simultaneously imaged, so that the measured element 300 is detected for defects.

[0042] As shown in Figure 1 and Figure 2 , the reflecting prisms can include first reflecting prisms 100 and second reflecting prisms 200, and the first reflecting prisms 100 are arranged around the second reflecting prisms 200 to form at least two detection positions. For example, three first reflecting prisms 100 and one second reflecting prism 200 can be arranged perpendicular to each other to form a detection position for placing the measured element 300, and the formed detection position can be a square or rectangular area. The specific size of each reflecting prism is not unique, and the size of the reflecting prism can be changed according to the different sizes and shapes (such as square or rectangular) of the measured element 300, so that the side surfaces and the front surface (or the back surface) of the measured element 300 of different sizes are imaged.

[0043] In the reflecting assembly 10, the combination of the first reflecting prisms 100 and the second reflecting prisms 200 is not unique, and can be combined in various ways (m*n) according to the field of view of the imaging module 30. For example, as shown in Figure 2 and Figure 10 , the reflecting assembly 10 can be designed as a 2*2 structure, two second reflecting prisms 200 are arranged, and six first reflecting prisms 100 are arranged around each second reflecting prism 200 to form a first detection position T1, a second detection position T2, etc., and four measured elements 300 can be simultaneously detected. When the size of the measured element 300 is small, the reflecting assembly 10 can also be designed as a 2*3 structure, as shown in Figure 11 , four second reflecting prisms 200 are arranged, and first reflecting prisms 100 are arranged around each second reflecting prism 200 to simultaneously detect six measured elements 300, etc.

[0044] In one embodiment, continuing to refer to Figure 1The first type of reflecting prism 100 and the second type of reflecting prism 200 are both isosceles right prisms. One of the right angles of the first type of reflecting prism 100 is arranged in parallel with the optical axis of the imaging module 20. The hypotenuse of each first type of reflecting prism 100 reflects the illumination light emitted by the light source module 20 to the side surface of the corresponding measured element 300, and reflects the light from the side surface of the corresponding measured element 300 to the imaging module 30, so as to image the multiple side surfaces of the measured element 300. The hypotenuse of the second type of reflecting prism 200 is arranged perpendicularly to the optical axis of the imaging module 20. The two right angles of the second type of reflecting prism 200 respectively reflect the illumination light emitted by the light source module 20 to the side surface of the corresponding measured element 300, and reflect the light from the side surface of the corresponding measured element 300 to the imaging module 30, so as to image the multiple side surfaces of the measured element 300.

[0045] Specifically, the hypotenuse of the first type of reflecting prism 100 and the two right angles of the second type of reflecting prism 200 can be coated with a reflecting film for reflecting light. Part of the illumination light emitted by the light source module 20 is incident on the hypotenuse of the first type of reflecting prism 100 and the two right angles of the second type of reflecting prism 200. The light is reflected by the first type of reflecting prism 100 and the second type of reflecting prism 200 to the side surface of the corresponding measured element 300. After being reflected by the side surface of the measured element 300, the light returns to the light source module 20 along the original path through the first type of reflecting prism 100 and the second type of reflecting prism 200. The light is transmitted by the light source module 20 to the imaging module 30 for imaging.

[0046] Further, as shown in Figure 2 , the reflecting assembly 10 further comprises a mounting module 1000 connecting the reflecting prisms. The mounting module 1000 is used for mounting the reflecting prisms and adjusting the relative positions between the reflecting prisms, so as to adapt to measured elements 300 of different sizes. Specifically, the mounting module 1000 can be designed as a mechanical structure, and is used for mounting the first type of reflecting prism 100 and the second type of reflecting prism 200 and adjusting the relative positions between the first type of reflecting prism 100 and the second type of reflecting prism 200. As shown in Figures 3 to 5 , taking the example that the first type of reflecting prism 100 and the second type of reflecting prism 200 are arranged perpendicularly to each other along the X-axis and the Y-axis, the mounting module 1000 can control the first type of reflecting prism 100 and the second type of reflecting prism 200 to move along the X-axis or the Y-axis, so as to adjust the relative positions between the first type of reflecting prism 100 and the second type of reflecting prism 200, change the size of the detection position, and adapt to the detection of measured elements 300 of multiple sizes.

[0047] The structure of the light source module 20 is also not unique. As shown in Figure 1 and Figure 6As shown, the light source module 20 can specifically include a ring light source 500 providing dark field illumination light, and / or a coaxial light source 600 providing bright field illumination light. Among them, the ring light source 500 can provide low-angle uniform dark field illumination light, and the surface height variation information of the measured element 300 can be obtained; the light emitted by the ring light source 500 is reflected by the reflecting prism after being scattered by the side of the measured element 300, and is received by the imaging module 30 for imaging.

[0048] The coaxial light source 600 can provide bright field illumination, and the coaxial light source 600 specifically includes a light source 601 and a half-transmission half-reflection film 602. The light source 601 is provided with a diffuse reflection plate in front (not shown in the figure), and the light emitted by the light source 601 passes through the half-transmission half-reflection film 602, part of the light directly transmits, and the other part is reflected to the first type of reflecting prism 100 and the second type of reflecting prism 200. The light reflected by the reflecting prism irradiates the side of the measured element 300, and the light reflected by the measured element 300 returns to the half-transmission half-reflection film 602 of the coaxial light source 600 along the original path, and the directly transmitted light is imaged to the imaging module 30. The coaxial light source 600 can provide uniform parallel light irradiation to obtain the outline size information of the measured element 300.

[0049] It can be understood that when the ring light source 500 and the coaxial light source 600 are included in the light source module 20 at the same time, the imaging is performed in the form of combined light source illumination, and the bright field illumination and the dark field illumination conditions are met at the same time.

[0050] Further, the ring light source 500 and / or the coaxial light source 600 can be a light source that can provide illumination light of multiple wavelengths. For example, Figure 7 As shown, according to the different colors of the surface features of the measured element 300, the ring light source 500 and / or the coaxial light source 600 can adopt a multi-wavelength light source, such as a multi-color light formed by mixing red, green and blue light, and the use of complementary colors can highlight the defect edges of the measured element 300, sharpen the boundaries, and improve the contrast of the defect boundaries. Alternatively, the coaxial light source 600 can use different wavelength light sources corresponding to different detection regions. For example, Figure 10 and Figure 11 As shown, the coaxial light source 600 region corresponding to the first detection position T1 uses a first wavelength light source, the coaxial light source 600 region corresponding to the second detection position T2 uses a second wavelength light source, and so on. In this way, the wavelength light source required by the corresponding coaxial light source 600 region can be set according to the differences in the types or defects of the chips in different detection positions, so that the chips with different types or defects can be effectively detected at the same time. In addition, as shown, Figure 7 The optical detection device further includes a filter 900 arranged between the imaging module 30 and the light source module 20. The filter 900 can be used to obtain different color light imaging effects, and different wavelength light sources can be used for irradiation. Different wavelengths can collect different characteristic information, and more abundant defect information can be obtained to facilitate detection of defects.

[0051] In one embodiment, as shown in Figure 7 The imaging module 30 includes an object-side telecentric lens 700 and a camera 800, and the field of view of the object-side telecentric lens 700 corresponds to a plurality of reflection assemblies 10. The object-side telecentric lens 700 can be a double telecentric lens or a non-image-side telecentric object-side telecentric lens, as long as it can achieve object-side telecentricity. The object-side telecentric lens 700 can eliminate the error caused by the inconsistency of the distance between the measured element 300 and the lens, and can more truly image the measured element 300, thereby facilitating defect detection. The camera 800 can be a monochrome or color camera, which can be selected according to actual needs.

[0052] In the imaging module 30, the object-side telecentric lens 700 is used instead of a general lens, which can eliminate the problem of different side clarity caused by the position offset of the measured element 300 in the detection position. As shown in Figure 8 When the measured element 300 is grabbed to the center of the detection position, the distances from the four sides of the measured element 300 to the reflection surface of the reflection prism are equal, the working distances of the object-side telecentric lens 700 are equal, and the imaging effects of the four sides are consistent, so that the defect detection can be directly performed. As shown in Figure 9 When the measured element 300 deviates from the center of the detection position, the distances from the four sides of the measured element 300 to the reflection surface of the reflection prism are inconsistent, causing different working distances. Since the object-side telecentric lens 700 can eliminate the error caused by the inconsistency of the distance between the measured element 300 and the lens, the sides of the measured element 300 can also be imaged. Therefore, for the same reflection assembly 10, different sizes of measured elements 300 can be detected, and the size range (that is, the field of view range) that can be detected by the optical detection device is determined according to the performance parameters of the object-side telecentric lens 700 and the camera 800. Figure 12 The schematic diagram of the camera 800 imaging the sides and the front (back) of the measured element 300 can well image each side of the measured element 300 for defect detection.

[0053] The above optical detection device has the following advantages:

[0054] 1. High detection efficiency. The coaxial light source 600 provides bright field illumination, and the annular light source 500 provides dark field illumination to provide sufficient illumination conditions for detecting defects on the sides of the chip. The imaging light path is folded by the mirror or the reflection prism to obtain the image information of the sides of the chip. In order to improve the detection efficiency, a detection scheme of multiple reflection assemblies 10 is provided. For small-sized chips, multiple chip side defects can be detected at the same time in batches, and the efficiency is greatly improved. For the requirement of changing the size of the chip, the reflection prism is controlled by the mounting module 1000 to combine different detection positions for detection, and the detection of the sides of a single chip can also be completed at one time.

[0055] 2. Simple structure. By assembling multiple reflective prisms in the mounting module 1000, detection of multiple chips can be achieved. Detection of other size chips can be replaced by different reflective prisms, and the structure of the corresponding mechanical gripper 400 is replaced, so that detection of other size chips can be achieved.

[0056] 3. Low cost. Different sizes of detection only need to replace part of the mechanical structure, without increasing other costs, and the replaced structure can be reused.

[0057] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the description.

[0058] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the utility model patent. It should be pointed out that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An optical detection device, characterized in that The application relates to an imaging device for multiple sides of a sample. The imaging device comprises: an imaging module; a light source module for providing illumination light to the sample; a plurality of reflection assemblies, each of which is arranged in a field of view of the imaging module, and each of which is used for reflecting light from at least two sides of a corresponding sample to the imaging module; 2. The optical detection device of claim 1, wherein, wherein the imaging module is used for receiving reflected light from the plurality of reflection assemblies to image the multiple sides of the sample.

3. The optical detection device of claim 2, wherein, The reflection assembly comprises a plurality of reflection prisms, and the plurality of reflection prisms surround a detection position for placing the sample. Part of the illumination light emitted by the light source module is reflected to multiple sides of the corresponding sample through the plurality of reflection prisms, and the reflection prisms reflect first imaging light from the multiple sides of the corresponding sample to the imaging module. Part of the illumination light emitted by the light source module is incident on a front surface or a back surface of the sample and forms second imaging light by reflection or scattering to the imaging module.

4. The optical detection device of claim 2, wherein, The imaging module receives the first imaging light and the second imaging light to simultaneously image the multiple sides of the sample and the front surface or the back surface of the sample.

5. The optical detection device of claim 4, wherein, The reflection prisms comprise first reflection prisms and second reflection prisms, the first reflection prisms are arranged around the second reflection prisms to form at least two detection positions. The first reflection prisms and the second reflection prisms are both isosceles right-angle prisms. One right-angle side of the first reflection prisms is arranged in parallel with an optical axis of the imaging module, and the hypotenuse of each of the first reflection prisms reflects the illumination light emitted by the light source module to the side of the corresponding sample and reflects light from the side of the corresponding sample to the imaging module to image the multiple sides of the sample.

6. The optical detection device of claim 2, wherein, The hypotenuse of the second reflection prisms is arranged perpendicularly to the optical axis of the imaging module, and the two right-angle sides of the second reflection prisms reflect the illumination light emitted by the light source module to the side of the corresponding sample and reflect light from the side of the corresponding sample to the imaging module to image the multiple sides of the sample.

7. The optical detection device according to any one of claims 1 to 6, characterized in that The reflection assembly further comprises a mounting module connected to the reflection prisms, and the mounting module is used for mounting the reflection prisms and adjusting the relative positions between the reflection prisms to adapt to samples of different sizes.

8. The optical detection device according to any one of claims 1 to 6, characterized in that The imaging module comprises a camera and an object-side telecentric lens, and a field of view of the object-side telecentric lens corresponds to the plurality of reflection assemblies.

9. The optical detection device of claim 8, wherein, The light source module comprises a ring-shaped light source for providing dark-field illumination light and / or a coaxial light source for providing bright-field illumination light.

10. The optical detection device according to any one of claims 1 to 6, characterized in that The ring-shaped light source and / or the coaxial light source are light sources capable of providing illumination light of multiple wavelengths. The imaging device further comprises a filter arranged between the imaging module and the light source module.

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