CN214953134U

CN214953134U - Optical detection system and detection equipment

Info

Publication number: CN214953134U
Application number: CN202022998100.1U
Authority: CN
Inventors: 陈鲁; 刘健鹏; 张嵩
Original assignee: Shenzhen Zhongke Feice Technology Co Ltd
Current assignee: Skyverse Ltd; Shenzhen Zhongke Feice Technology Co Ltd
Priority date: 2020-12-14
Filing date: 2020-12-14
Publication date: 2021-11-30
Anticipated expiration: 2030-12-14

Abstract

The utility model discloses an optical detection system and check out test set, optical detection system includes first light source and second light source, first light source has the cavity, the cavity has hemispherical light emitting area, the light of first light source passes the inner space directive determinand of cavity, be equipped with the through-hole on the chamber wall of cavity, the light of second light source passes the through-hole with the inner space directive of cavity the determinand, optical detection system still includes the information acquisition subassembly, the information acquisition subassembly passes through the through-hole is gathered the light of first light source with the light warp of second light source the optical information that the determinand was rolled over back. By applying the scheme, the edge area of the object to be detected is positioned in the irradiation range of the first light source and the second light source, so that the effective bright field illumination of the edge area of the object to be detected can be realized, and the notch inclined plane of the object to be detected also has higher illumination efficiency.

Description

Optical detection system and detection equipment

Technical Field

The utility model relates to a detect technical field, especially relate to an optical detection system and check out test set.

Background

The manufacturing process of the semiconductor chip is very complex, each qualified semiconductor chip needs to be accurately controlled, each manufacturing process cannot be polluted by the previous process, and a small defect is overlapped by a plurality of processes, so that the yield of a final product is greatly influenced, and the manufacturing cost is increased.

Therefore, the requirement of the multi-semiconductor chip detection device is higher and higher, and the multi-semiconductor chip detection device can detect not only the defects on the front side of the semiconductor chip but also the defects on the edge of the semiconductor chip.

Because the slope change of the edge area of the semiconductor chip is large, the current detection equipment cannot carry out effective bright field illumination on the edge area of the semiconductor chip. Especially, in the semiconductor chip 01 shown in fig. 1, which is provided with a notch 011 (provided for chip alignment) in the edge region, a vertical surface a and an inclined surface b are formed at the notch 011, and the illumination efficiency on the inclined surface b is very low, so that the notch inclined surface b cannot be clearly imaged.

In view of the above, how to effectively illuminate the edge area of the semiconductor chip with bright field is a technical problem to be solved by those skilled in the art.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides an optical detection system, optical detection system includes first light source and second light source, first light source has the cavity, the cavity has hemispherical light emitting area, the light of first light source passes the inner space directive determinand of cavity, be equipped with the through-hole on the chamber wall of cavity, the light of second light source passes the through-hole with the inner space directive of cavity the determinand, optical detection system still includes the information acquisition subassembly, the information acquisition subassembly passes through the through-hole is gathered the light of first light source with the light warp of second light source the optical information that the determinand was rolled over back.

In one embodiment, the second light source is a coaxial light source, and the imaging optical axis of the information acquisition assembly is coaxial with the optical axis of the coaxial light source.

In one embodiment, the light splitting proportion of the light splitting sheet of the coaxial light source is 50% to 50%.

In one embodiment, a plurality of coaxial light sources are provided, and the coaxial light sources are mounted on the outer wall surface of the cavity of the first light source at equal intervals and correspond to the through holes in the first light source one by one.

In one embodiment, the optical axes of at least two of said coaxial light sources intersect each other.

In one embodiment, the first light source is a dome light source having a circular opening facing the test object.

In one embodiment, the lighting pattern of the first and second light sources is a brightness enhancing strobe pattern.

In one embodiment, the light emission patterns of the first and second light sources satisfy 2500< n x t x L <5000, where t is a light emission time, L is a light emission average luminance during the t time, and n is a number of times the light source emits light during one exposure time.

In one embodiment, the light emitting mode of the first light source and the second light source is a normally-on mode, and the first light source and the second light source are both provided with a heat dissipation structure.

In one embodiment, the information acquisition assembly includes a detection unit including a detector, and an aperture of a through hole on the first light source is not smaller than a lens clear aperture of the detector corresponding to the through hole.

In one embodiment, the detector is an area array detector, and the lens of the detector is an object-side telecentric lens.

In one embodiment, the photographing mode of the detection unit is that all the detectors are exposed and imaged at the same time.

In one embodiment, the photographing mode of the detecting unit is that the detector photographs in multiple steps along the extending direction of the optical axis, and each time the image is photographed, the image is moved along the optical axis by the length of one depth of field.

Additionally, the utility model provides a check out test set, including the bearing system that is used for bearing the determinand and above-mentioned arbitrary item optical detection system, bearing system can rotate, optical detection system is to placing the determinand on the bearing system detects.

The utility model provides an optical detection system utilizes the combination of first light source and second light source, has realized the effective bright field illumination to the determinand, during the application, lets the marginal area of determinand be located the irradiation range of first light source and second light source, can realize the effective bright field illumination to the marginal area of determinand to, also have higher lighting efficiency on can making the breach inclined plane of determinand.

Drawings

FIG. 1 is a schematic view of a semiconductor chip having a notch in an edge region thereof;

fig. 2 is a schematic perspective view of an embodiment of an optical inspection system provided by the present invention;

FIG. 3 is a cross-sectional view of FIG. 2;

FIG. 4 is a schematic diagram showing the positions of the optical axes of the three coaxial light sources and the wall of the gap in FIG. 2;

fig. 5 is a rear view of the domed light source of fig. 2.

The reference numerals are explained below:

01 chip, 011 gap, a vertical surface and b inclined surface;

10 dome light source, 101 through hole; 20 coaxial light sources; 30 detectors.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the following provides a detailed description of the technical solution of the present invention with reference to the accompanying drawings.

As shown in fig. 2, the optical detection system provided by the present invention includes a first light source, a second light source and an information collecting assembly.

The first light source is provided with a cavity, and the cavity is provided with a hemispherical luminous surface. The light of the first light source is emitted from the light emitting surface of the cavity, penetrates through the inner space of the cavity and is emitted to the object to be detected, and specifically can be emitted to the edge area of the object to be detected.

The walls of the cavity of the first light source are provided with through holes 101 (as understood in connection with fig. 5). The light of the second light source is emitted to the object to be measured through the through hole 101 of the first light source, and specifically, can be emitted to the edge area of the object to be measured.

The information acquisition assembly acquires optical information returned by the light of the first light source and the light of the second light source through the through hole 101 in the first light source.

By applying the scheme, the edge area of the object to be detected can be effectively illuminated in bright field, the edge area of the object to be detected in the detection process can be clearly imaged, and the defect missing detection on the edge area of the object to be detected is prevented.

Specifically, the first light source may be a dome light source 10, a circular opening is provided on the dome light source 10, the circular opening faces the object to be measured, and the light passes through the circular opening and then irradiates the object to be measured.

Specifically, the second light source may be a coaxial light source 20, and the splitting ratio of the light splitting plate of the coaxial light source 20 is preferably 50%: 50%, so that a higher luminous efficiency can be obtained.

The coaxial light source 20 may be mounted on the outer wall of the cavity of the first light source. The number of coaxial light sources may be one or more (i.e., two or more), and three coaxial light sources 20 are provided in the figure. When a plurality of coaxial light sources 20 are arranged, a plurality of through holes 101 need to be correspondingly arranged on the first light source, and the light rays of each coaxial light source 20 correspondingly penetrate through the through holes 101 on the first light source one by one to irradiate on an object to be measured.

The through holes 101 can be arranged at equal intervals, so that the coaxial light sources 20 are arranged at equal intervals on the outer wall surface of the cavity of the first light source, and the illumination uniformity is better.

The optical axes of the coaxial light sources 20 may intersect with each other, so that when a notch is formed in the edge area of the object to be measured, higher illumination efficiency can be obtained on each wall surface of the notch. For example, in the illustrated embodiment (as shown in fig. 4), when the notch 011 at the edge of the object to be tested is rotated into the circular opening area of the dome light source, the optical axis of the central coaxial light source intersects with the optical axes of the coaxial light sources at two sides at a point, and then the light beams are scattered and irradiated onto the wall surface of the notch 011, the optical axis of the central coaxial light source is irradiated onto the vertical surface of the notch 011, the light beams of the coaxial light sources at two sides are irradiated onto the inclined surfaces at two sides of the notch, and the vertical surface and the inclined surface of the notch have high illumination efficiency.

Specifically, too large a diameter of the dome light source 10 may result in a large system footprint, and also may cause the total size (i.e. the distance indicated by M in fig. 3) of the coaxial light source 20 and the dome light source 10 in the optical axis direction to be too large, which may result in a long imaging distance of the information collecting assembly, which is not favorable for clear imaging, and is unfavorable for safety of loading and unloading of the object to be measured. Therefore, the dome light source only needs to meet the opening requirement of the through hole 101, and does not need to be arranged too large. The diameter of the dome light source 10 is preferably set to about 50mm, and the total size of the coaxial light source 20 and the dome light source 10 in the optical axis direction is preferably set to 110mm or less.

Specifically, the coaxial light source 20 and the dome light source 10 may be light sources whose light emitting mode is a brightness enhancing strobe mode. The brightening stroboscopic is a light-emitting mode commonly used in the industry, and in the light-emitting mode, a light source emits high light intensity in a very short time, the time length is close to the exposure time of a camera, and light sources in other non-exposure time periods do not emit light. Such a light source generates less total heat.

When the coaxial light source 20 and the dome light source 10 are set as the light source of the brightness enhancement strobe mode, the preferable configuration is: the light emitting time t is configured to be within 70us, the light emitting average brightness L is configured to be more than 70 ten thousand nit, the duty ratio eta is configured to be less than 50%, the lens exposure time nt/eta is configured to be 70us, and the light emitting times n of the light source in one exposure time are configured to be 1 time.

It should be noted that different chip forming processes lead to different surface optical reflection characteristics, so when different chips are detected, the strobe time needs to be adaptively adjusted, and the adjustment basis is that an image with an average gray level of about 200DN (Digital Number, remote sensing image pixel brightness value) is obtained in a short time, and no obvious saturation point exists in the image.

Alternatively, the coaxial light source 20 and the dome light source 10 may be light sources having a light emission pattern satisfying 2500< n t L <5000, where t is light emission time in units of us, L is light emission average luminance in units of nit, and n is the number of times the light source emits light within one exposure time.

Still alternatively, the coaxial light source 20 and the dome light source 10 may also be normally bright light sources provided with heat dissipating structures. The heat dissipation form can be air cooling or water cooling.

Specifically, when the second light source is coaxial light source 20, can let the formation of image optical axis of information acquisition subassembly coaxial with coaxial light source 20's optical axis, like this, it is more clear to image, and detection accuracy is higher. The information acquisition assembly comprises a detection unit, the detection unit comprises a detector 30, and an imaging optical axis of the information acquisition assembly is a lens optical axis of the detector 30.

In the illustrated embodiment, three detectors 30 are provided, optical axes of lenses of the three detectors 30 coincide with optical axes of the three coaxial light sources 20, respectively, and apertures of the three through holes on the dome light source 10 are not smaller than the corresponding optical apertures of the lenses of the detectors 30.

In particular, the detector 30 is preferably an area array detector, and the lens of the detector is preferably an object-side telecentric lens, so that clearer imaging can be obtained.

Specifically, the photographing mode of the detection unit may be that all the detectors 30 are exposed and imaged at the same time. When exposure imaging is carried out, the coaxial light sources 20 and the dome light source 10 emit light synchronously. Thus, the imaging of the entire region of the target position of the object can be obtained at once.

Alternatively, the photographing mode of the detection unit may be multi-step photographing along the direction in which the optical axis extends. And moving the optical axis for one depth of field every time the image is taken until all the regions of the target position of the object to be detected are clearly imaged, and then selecting clear parts in all the images to splice into clear images. In this way, clearer imaging can be obtained.

Additionally, the utility model provides a check out test set, including the bearing system and the aforesaid arbitrary any that are used for bearing the determinand the optical detection system, bearing system can drive the determinand rotatory, optical detection system detects the determinand of placing on bearing system.

It is right above the utility model provides an optical detection system and check out test set have carried out detailed introduction. The principles and embodiments of the present invention have been explained herein using specific examples, and the above descriptions of the embodiments are only used to help understand the method and its core ideas of the present invention. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.

Claims

1. The optical detection system is characterized by comprising a first light source and a second light source, wherein the first light source is provided with a cavity, the cavity is provided with a hemispherical light emitting surface, light of the first light source penetrates through the inner space of the cavity and emits to an object to be detected, a through hole (101) is formed in the wall of the cavity, light of the second light source penetrates through the through hole (101) and the inner space of the cavity and emits to the object to be detected, the optical detection system further comprises an information acquisition component, and the information acquisition component acquires optical information, returned by the object to be detected, of the light of the first light source and the light of the second light source through the through hole (101).

2. The optical detection system according to claim 1, wherein the second light source is a coaxial light source (20), and an imaging optical axis of the information acquisition assembly is coaxial with an optical axis of the coaxial light source (20).

3. The optical inspection system of claim 2, wherein the ratio of the split of the coaxial light source (20) is 50% to 50%.

4. The optical detection system according to claim 2, wherein a plurality of the coaxial light sources (20) are provided, and the coaxial light sources (20) are mounted on the outer wall surface of the cavity of the first light source at equal intervals and correspond to the through holes (101) in the first light source one by one.

5. Optical detection system according to claim 4, characterized in that the optical axes of at least two of the coaxial light sources (20) cross each other.

6. The optical detection system according to claim 1, characterized in that the first light source is a dome light source (10) having a circular opening towards the object to be measured.

7. The optical inspection system of any of claims 1-6, wherein the light emission pattern of the first and second light sources is a brightness enhancement strobe pattern;

or the light emitting patterns of the first light source and the second light source meet 2500< n t L <5000, wherein t is light emitting time, L is light emitting average brightness in t time, and n is light emitting times of the light source in one exposure time;

or the light emitting modes of the first light source and the second light source are normal light modes, and the first light source and the second light source are both provided with heat dissipation structures.

8. The optical detection system according to any one of claims 1 to 6, wherein the information acquisition assembly comprises a detection unit, the detection unit comprises a detector (30), and the aperture of the through hole (101) on the first light source is not smaller than the lens clear aperture of the detector (30) corresponding to the aperture.

9. The optical inspection system of claim 8, wherein the detector (30) is an area array detector and the lens of the detector (30) is an object-side telecentric lens.

10. The optical detection system according to claim 8, characterized in that the photographing mode of the detection unit is simultaneous exposure imaging of all the detectors (30);

or the photographing mode of the detection unit is that the detector (30) photographs in multiple steps along the extension direction of the optical axis, and the detector moves for the length of one depth of field along the optical axis every time the detector photographs once.

11. Detection device, characterized in that it comprises a carrying system for carrying an object to be tested, said carrying system being rotatable, and an optical detection system according to any one of claims 1-10 for detecting an object to be tested placed on said carrying system.