CN116818667A - A 2D and 3D integrated semiconductor microscopic vision inspection system and method - Google Patents

Abstract

The application relates to the technical field of wafer surface defect detection, in particular to a 2D and 3D integrated semiconductor microscopic vision detection system and method. The system comprises a left optical image acquisition unit, a middle optical image acquisition unit and a right optical image acquisition unit which are distributed in space, wherein central axes of the left optical image acquisition unit, the middle optical image acquisition unit and the right optical image acquisition unit are positioned on the same vertical plane, and lower areas of the left optical image acquisition unit, the middle optical image acquisition unit and the right optical image acquisition unit form an image acquisition area; the left optical image acquisition unit is used for acquiring image information on the left side of the image acquisition area, the middle optical image acquisition unit is used for acquiring image information on the middle part of the image acquisition area, and the right optical image acquisition unit is used for acquiring image information on the right side of the image acquisition area. The method is implemented based on the system. The application can realize accurate acquisition of the original image data, thereby being beneficial to the improvement of the follow-up defect detection precision.

Description

A 2D and 3D integrated semiconductor microscopic vision inspection system and method

Technical field

The invention relates to the technical field of wafer surface defect detection, and specifically to a 2D and 3D integrated semiconductor microscopic visual inspection system and method.

Background technique

In semiconductor inspection, common inspection systems on the market are divided into three optical systems, namely 2D main inspection system, 2D re-inspection system and 3D inspection system. Among them, the 2D main inspection system and the 2D re-inspection system are mainly used to detect 2D information including length and width of wafer surface defects, and the 3D inspection system is mainly used to detect 3D information including height of wafer surface defects. At present, in the detection of wafer surface defects, 3D information is usually detected and obtained in the form of line structured light, which is based on the original image collected by the optical imaging system and obtained by using relevant image processing algorithms; however, due to the surface of the wafer There are many types of defects. When a conventional inspection system collects image data, there will be a detection blind area due to the obstruction of the surface defects of the wafer. The existence of this detection blind area will greatly reduce the accuracy of defect detection.

Contents of the invention

The present invention provides a 2D and 3D integrated semiconductor microscopic vision inspection system, which can overcome some or some defects of the existing technology.

A 2D and 3D integrated semiconductor microscopic vision inspection system according to the present invention includes a spatially distributed left optical image acquisition unit, a middle optical image acquisition unit and a right optical image acquisition unit. The central axes of the optical image acquisition unit and the right optical image acquisition unit are located on the same vertical plane, and the lower areas of the left optical image acquisition unit, the middle optical image acquisition unit and the right optical image acquisition unit form an image acquisition area;

The left optical image acquisition unit is used to collect image information on the left side of the image acquisition area, the middle optical image acquisition unit is used to collect image information in the middle of the image acquisition area, and the right optical image acquisition unit is used to collect image information on the right side of the image acquisition area.

Through the above design, 2D (implemented by the middle optical image acquisition unit 120) and 3D detection (implemented by the left optical image acquisition unit 110 and right optical image acquisition unit 130) can be integrated into a set of optical systems. The object) is inspected, and the 2D and 3D information of the wafer can be better obtained through one scan; therefore, while ensuring the inspection accuracy, the speed of wafer inspection is greatly accelerated.

Preferably, the left optical image acquisition unit has a left light tube assembly, a left high-power telecentric lens assembly is provided at the front end of the left light tube assembly, and a left camera assembly is provided at the rear end of the left light tube assembly; a left coaxial light source assembly is provided at the left light tube assembly, The left coaxial light source component is used to generate left line structured light, and the left camera component is used to receive the reflected light generated by the left line structured light at the image acquisition area;

The medium optical image acquisition unit has a medium light tube assembly. A medium and high-power telecentric lens assembly is provided at the front end of the medium light tube assembly. A medium camera assembly is provided at the rear end of the medium light tube assembly. A medium coaxial light source assembly is also provided at the middle light tube assembly. The axial light source component is used to generate centerline structured light, and the mid-camera component is used to receive the reflected light generated by the centerline structured light in the image acquisition area;

The right optical image acquisition unit has a right light tube assembly, a right high-power telecentric lens assembly is provided at the front end of the right light tube assembly, and a right camera assembly is provided at the rear end of the right light tube assembly; a right coaxial light source assembly is also provided at the right light tube assembly, and a right coaxial light source assembly is provided at the right end of the right light tube assembly. The axial light source component is used to generate right-line structured light, and the right camera component is used to receive the reflected light generated by the right-line structured light at the image acquisition area.

Through the above design, the left optical image acquisition unit, the middle optical image acquisition unit and the right optical image acquisition unit can operate synchronously, that is, when the wafer is in a certain state, the wafer can be collected from the left, middle and right at the same time ( That is, the image at the image acquisition area); therefore, during subsequent algorithm processing, the data of all images can compensate or correct each other, so the accuracy and resolution of defect detection can be effectively improved.

Preferably, a side-left camera assembly is also provided at the left light tube assembly, and the side-left camera assembly is used to receive the reflected light generated by the right-line structured light at the image acquisition area;

A right-side camera component is also provided at the right light tube component, and the right-side camera component is used to receive the reflected light generated by the left-line structured light in the image acquisition area.

This design makes it possible to better address the problem of triangular blind spots existing in the existing use of structured light image calculations to obtain 3D information, so it can better achieve the reproduction of wafer 3D images and make the detection results more realistic.

Preferably, the left high-power telecentric lens assembly, the middle high-power telecentric lens assembly and the right high-power telecentric lens assembly all have a lens mounting barrel and a front lens lens and a rear lens lens located at both ends of the lens mounting barrel. Therefore, the collection of relevant images can be better realized.

Preferably, the left coaxial light source assembly, the middle coaxial light source assembly and the right coaxial light source assembly are vertically located at the left light tube assembly, the middle light tube assembly and the right light tube assembly respectively; the left coaxial light source assembly, the middle coaxial light source Both the assembly and the right coaxial light source assembly include a light source, a slit piece, a first light source lens, a second light source lens and a first beam splitter arranged in sequence. The first beam splitter is a semi-transparent and half mirror. Therefore, the construction of the incident light path and the reflected light path can be better realized.

Preferably, the left side camera assembly and the right side camera assembly are vertically disposed at the left light tube assembly and the right light tube assembly respectively, and both the side left camera assembly and the right side camera assembly include a second spectroscope, and the second spectroscope is a long-wave pass Beam splitter, left-line structured light and right-line structured light are short-wave light sources. Therefore, it is possible to better filter out stray light and achieve better collection of relevant images.

Preferably, the wavelengths of the left-line structured light and the right-line structured light do not exceed 405 nm.

Preferably, the left optical image acquisition unit, the middle optical image acquisition unit and the right optical image acquisition unit are all provided with surface light sources. This makes it possible to better construct bright field or dark field detection effects according to different detection requirements; and allows the bright field and dark field effects to coexist in a single detection, so the detection effect can be effectively improved.

In addition, the present invention also provides a 2D and 3D integrated semiconductor microscopic visual inspection method, which is implemented by using any one of the above-mentioned 2D and 3D integrated semiconductor microscopic visual inspection systems. Therefore, the accurate collection of original image data can be better achieved, which is conducive to improving the accuracy of subsequent defect detection.

Description of the drawings

Figure 1 is a schematic diagram of the system in Embodiment 1;

Figure 2 is a schematic diagram of the light source assembly and the high-power telecentric lens assembly in Embodiment 1;

Figure 3 is a schematic diagram of the left optical image acquisition unit in Embodiment 1

Figure 4 is a schematic diagram of the method in Embodiment 1;

Figure 5 is a schematic diagram of the left optical image acquisition unit collecting the reflected light image at the right optical image acquisition unit in Embodiment 1;

FIG. 6 is a schematic diagram of the right optical image acquisition unit acquiring the reflected light image at the left optical image acquisition unit in Embodiment 1.

Detailed ways

In order to further understand the content of the present invention, the present invention will be described in detail with reference to examples. It should be understood that the embodiments are only for explanation of the present invention but not for limitation.

Example 1

As shown in Figure 1, this embodiment provides a 2D and 3D integrated semiconductor microscopic vision inspection image acquisition system, which includes a spatially distributed left optical image acquisition unit 110, a middle optical image acquisition unit 120 and a right optical image acquisition unit. Unit 130, the central axis of the left optical image acquisition unit 110, the middle optical image acquisition unit 120 and the right optical image acquisition unit 130 is located on the same vertical plane, the left optical image acquisition unit 110, the middle optical image acquisition unit 120 and the right optical image The lower area of the acquisition unit 130 forms an image acquisition area;

The left optical image acquisition unit 110 is used to collect image information on the left side of the image acquisition area, the middle optical image acquisition unit 120 is used to collect image information in the middle of the image acquisition area, and the right optical image acquisition unit 130 is used to collect image information on the right side of the image acquisition area. Image information.

Through the above design, 2D (implemented by the middle optical image acquisition unit 120) and 3D detection (implemented by the left optical image acquisition unit 110 and right optical image acquisition unit 130) can be integrated into a set of optical systems. The object) is inspected, and the 2D and 3D information of the wafer can be better obtained through one scan; therefore, while ensuring the inspection accuracy, the speed of wafer inspection is greatly accelerated.

It can be known that in this embodiment, due to the symmetrical design of the left optical image acquisition unit 110 and the right optical image acquisition unit 130, the image information of the wafer can be better collected from different angles at the same time, so the image information of the wafer can be better eliminated. The blind area of image acquisition enables the acquisition accuracy of 3D information to reach 0.1um and the resolution to 0.05um.

In addition, the design of the middle optical image acquisition unit 120 enables the collection of relatively accurate 2D information of the wafer at the same time, so that in subsequent processing, the image collected by the middle optical image acquisition unit 120 can be used as the basis for the 2D information, and the left optical The image acquisition unit 110 and the right optical image acquisition unit 130 perform correction of 2D information, so the accuracy and resolution of defect detection can be further improved.

In this embodiment,

The left optical image acquisition unit 110 has a left light tube assembly 111. A left high-power telecentric lens assembly 112 is provided at the front end of the left light tube assembly 111, and a left camera assembly 113 is provided at the rear end of the left light tube assembly 111; a left telecentric lens assembly 112 is provided at the left light tube assembly 111. The axial light source component 114, the left coaxial light source component 114 is used to generate the left line structured light 115, and the left camera component 113 is used to receive the reflected light generated by the left line structured light 115 at the image acquisition area;

The mid-optical image acquisition unit 120 has a mid-lens tube assembly 121. The mid-lens tube assembly 121 is provided with a mid-range and high-power telecentric lens assembly 122 at the front end. The mid-lens tube assembly 121 is provided with a mid-range camera assembly 123 at the rear end; the mid-lens tube assembly 121 is also provided with a mid-range camera assembly 123 Coaxial light source assembly 124, the middle coaxial light source assembly 124 is used to generate the centerline structured light 125, and the middle camera assembly 123 is used to receive the reflected light generated by the centerline structured light 125 at the image acquisition area;

The right optical image acquisition unit 130 has a right light tube assembly 131. A right high-power telecentric lens assembly 132 is provided at the front end of the right light tube assembly 131, and a right camera assembly 133 is provided at the rear end of the right light tube assembly 131; a right light tube assembly 131 is also provided with a right high-power telecentric lens assembly 132. The coaxial light source assembly 134, the right coaxial light source assembly 134 is used to generate the right line structured light 135, and the right camera assembly 133 is used to receive the reflected light generated by the right line structured light 135 at the image acquisition area.

Through the above design, the left optical image acquisition unit 110, the middle optical image acquisition unit 120 and the right optical image acquisition unit 130 can operate synchronously, that is, when the wafer is in a certain same state, it can collect data from the left, middle and right at the same time. The image of the wafer (that is, the image acquisition area); therefore, during the subsequent algorithm processing, the data of all images can be compensated or corrected with each other, so the accuracy and resolution of defect detection can be effectively improved.

In this embodiment,

The left light tube assembly 111 is also provided with a side-left camera assembly 116, which is used to receive the reflected light generated by the right-line structured light 135 at the image acquisition area;

The right light tube assembly 131 is also provided with a right side camera assembly 136, which is used to receive the reflected light generated by the left line structured light 115 in the image acquisition area.

This design makes it possible to better address the problem of triangular blind spots existing in the existing use of structured light image calculations to obtain 3D information, so it can better achieve the reproduction of wafer 3D images and make the detection results more realistic.

That is, through one scan, both the left optical image acquisition unit 110 and the right optical image acquisition unit 130 can acquire 3D image data of 2 wafers, and through the subsequent weighted calculation and data of the total 4 3D image data, Fusion and other processing can better improve the accuracy of defect detection.

In this embodiment, the left high-power telecentric lens assembly 112, the middle high-power telecentric lens assembly 122, and the right high-power telecentric lens assembly 132 all have a lens mounting barrel 211 and front lens lenses 212 and 212 located at both ends of the lens mounting barrel 211. Rear lens 213. Therefore, the collection of relevant images can be better realized.

In this embodiment, the left coaxial light source assembly 114, the middle coaxial light source assembly 124 and the right coaxial light source assembly 134 are respectively vertically disposed at the left light tube assembly 111, the middle light tube assembly 121 and the right light tube assembly 131; The axial light source assembly 114, the middle coaxial light source assembly 124 and the right coaxial light source assembly 134 each include a light source 221, a slit piece 222, a first light source lens 223, a second light source lens 224 and a first beam splitter 225 arranged in sequence. A beam splitter 225 is a semi-transparent mirror. Therefore, the construction of the incident light path and the reflected light path can be better realized.

In this embodiment, the left camera assembly 116 and the right camera assembly 136 are vertically disposed at the left light tube assembly 111 and the right light tube assembly 131 respectively. The left camera assembly 116 and the right camera assembly 136 both include a second beam splitter. 310. The second beam splitter 310 is a long-wavelength beam splitter, and the left-line structured light 115 and the right-line structured light 135 are both short-wave light sources. Therefore, it is possible to better filter out stray light and achieve better collection of relevant images.

In this embodiment, the wavelengths of the left-line structured light 115 and the right-line structured light 135 do not exceed 405 nm.

In this embodiment, the left optical image acquisition unit 110, the middle optical image acquisition unit 120 and the right optical image acquisition unit 130 are all provided with surface light sources. This makes it possible to better construct bright field or dark field detection effects according to different detection requirements; and allows the bright field and dark field effects to coexist in a single detection, so the detection effect can be effectively improved.

Based on the above system of this embodiment, this embodiment also provides a 2D and 3D integrated semiconductor microscopic visual inspection image acquisition method, which is implemented using the above system. Therefore, the accurate collection of original image data can be better achieved, which is conducive to improving the accuracy of subsequent defect detection.

As shown in Figure 4, during the actual image acquisition process, the left coaxial light source assembly 114, the middle coaxial light source assembly 124 and the right coaxial light source assembly 134 can be turned on at the same time; at this time, the middle optical image acquisition unit 120 can only be used for acquisition. The left optical image acquisition unit 110 and the right optical image acquisition unit 130 can simultaneously collect the reflected light of their own light source and the opposite side light source. Reflected light, so it can better acquire 4 3D image data at different angles.

See Figure 5, which is a schematic diagram of the left optical image acquisition unit 110 collecting the reflected light image at the right optical image acquisition unit 130;

As shown in FIG. 6 , it is a schematic diagram of the right optical image acquisition unit 130 collecting the reflected light image at the left optical image acquisition unit 110 .

In addition, by controlling the opening sequence or quantity of the surface light sources at the left optical image acquisition unit 110 , the middle optical image acquisition unit 120 and the right optical image acquisition unit 130 , the left optical image acquisition unit 110 , the middle optical image acquisition unit 130 can be realized 120 and the right optical image acquisition unit 130 can simultaneously realize the acquisition of images under bright field and dark field effects.

It is easily understood that, based on one or several embodiments provided in this application, those skilled in the art can combine, split, recombine, etc. the embodiments of this application to obtain other embodiments, and these embodiments do not exceed the scope of this application. The scope of protection applied for.

The present invention and its implementation have been schematically described above. This description is not limiting. The examples shown are only part of the implementation of the present invention, and the actual structure is not limited thereto. Therefore, if a person of ordinary skill in the art is inspired by the invention and without departing from the spirit of the invention, can devise structural methods and embodiments similar to the technical solution without inventiveness, they shall all fall within the protection scope of the invention. .

Claims (9)

1. A 2D and 3D integrated semiconductor microscopic vision inspection system, characterized by: including a spatially distributed left optical image acquisition unit (110), a middle optical image acquisition unit (120) and a right optical image acquisition unit ( 130), the central axes of the left optical image acquisition unit (110), the middle optical image acquisition unit (120) and the right optical image acquisition unit (130) are located on the same vertical plane, the left optical image acquisition unit (110), the middle optical image acquisition unit (130) The image acquisition unit (120) and the lower area of the right optical image acquisition unit (130) form an image acquisition area; The left optical image acquisition unit (110) is used to collect image information on the left side of the image acquisition area, the middle optical image acquisition unit (120) is used to collect image information in the middle of the image acquisition area, and the right optical image acquisition unit (130) is used to collect image information on the left side of the image acquisition area. Image information on the right side of the image acquisition area. 2. A 2D and 3D integrated semiconductor microscopic vision inspection system according to claim 1, characterized in that: The left optical image acquisition unit (110) has a left light tube assembly (111). A left high-power telecentric lens assembly (112) is provided at the front end of the left light tube assembly (111), and a left camera assembly (112) is provided at the rear end of the left light tube assembly (111). 113); a left coaxial light source assembly (114) is provided at the left light tube assembly (111), the left coaxial light source assembly (114) is used to generate the left line structured light (115), and the left camera assembly (113) is used to receive the left The reflected light generated by line structured light (115) at the image collection area; The medium optical image acquisition unit (120) has a medium light tube assembly (121). The front end of the medium light tube assembly (121) is provided with a medium and high-power telecentric lens assembly (122). The rear end of the medium light tube assembly (121) is provided with a medium camera assembly (122). 123); a central coaxial light source component (124) is also provided at the central light tube component (121). The central coaxial light source component (124) is used to generate the central line structured light (125), and the central camera component (123) is used to receive the central line The reflected light generated by structured light (125) at the image collection area; The right optical image acquisition unit (130) has a right light tube assembly (131), a right high-power telecentric lens assembly (132) is provided at the front end of the right light tube assembly (131), and a right camera assembly (132) is provided at the rear end of the right light tube assembly (131). 133); the right light tube assembly (131) is also provided with a right coaxial light source assembly (134), the right coaxial light source assembly (134) is used to generate the right line structured light (135), and the right camera assembly (133) is used to receive The right line is the reflected light generated by structured light (135) at the image acquisition area. 3. A 2D and 3D integrated semiconductor microscopic vision inspection system according to claim 2, characterized in that: A side-left camera assembly (116) is also provided at the left light tube assembly (111), and the side-left camera assembly (116) is used to receive the reflected light generated by the right-line structured light (135) in the image acquisition area; A right side camera assembly (136) is also provided at the right light tube assembly (131), and the right side camera assembly (136) is used to receive the reflected light generated by the left line structured light (115) in the image acquisition area. 4. A 2D and 3D integrated semiconductor microscopic vision inspection system according to claim 2, characterized in that: a left high-power telecentric lens assembly (112), a middle-high power telecentric lens assembly (122) and a right high-power telecentric lens assembly (122). The central lens assembly (132) has a lens mounting barrel (211) and a front lens lens (212) and a rear lens lens (213) located at both ends of the lens mounting barrel (211). 5. A 2D and 3D integrated semiconductor microscopic vision inspection system according to claim 2, characterized by: a left coaxial light source assembly (114), a middle coaxial light source assembly (124) and a right coaxial light source assembly. (134) are respectively vertically located at the left light tube assembly (111), the middle light tube assembly (121) and the right light tube assembly (131); the left coaxial light source assembly (114), the middle coaxial light source assembly (124) and The right coaxial light source components (134) each include a light source (221), a slit piece (222), a first light source lens (223), a second light source lens (224) and a first beam splitter (225) arranged in sequence. One beam splitter (225) is a semi-transparent and half-reflecting mirror. 6. A 2D and 3D integrated semiconductor microscopic vision inspection system according to claim 3, characterized in that: the left side camera assembly (116) and the right side camera assembly (136) are respectively arranged vertically on the left light tube assembly. (111) and the right light tube assembly (131), the left side camera assembly (116) and the side right camera assembly (136) both include a second beam splitter (310), and the second beam splitter (310) is a long-wave pass beam splitter. , the left structured light (115) and the right structured light (135) are both short-wave light sources. 7. A 2D and 3D integrated semiconductor microscopic vision inspection system according to claim 6, characterized in that: the wavelengths of the left-line structured light (115) and the right-line structured light (135) do not exceed 405 nm. 8. A 2D and 3D integrated semiconductor microscopic vision inspection system according to claim 6, characterized by: a left optical image acquisition unit (110), a middle optical image acquisition unit (120) and a right optical image acquisition unit Surface light sources are installed everywhere (130). 9. A 2D and 3D integrated semiconductor microscopic visual inspection method, which is implemented using a 2D and 3D integrated semiconductor microscopic visual inspection system according to any one of claims 1-8.