CN114184138B - Detection device and detection method - Google Patents
Detection device and detection method Download PDFInfo
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- CN114184138B CN114184138B CN202010857187.2A CN202010857187A CN114184138B CN 114184138 B CN114184138 B CN 114184138B CN 202010857187 A CN202010857187 A CN 202010857187A CN 114184138 B CN114184138 B CN 114184138B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
- F21S2/00—Systems of lighting devices, not provided for in main groups F21S4/00 - F21S10/00 or F21S19/00, e.g. of modular construction
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/10—Measuring as part of the manufacturing process
- H01L22/12—Measuring as part of the manufacturing process for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions
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Abstract
The application discloses a detection device and a detection method. The detection device comprises: an illumination assembly and an imaging assembly; the lighting assembly includes: a dome assembly; the imaging assembly includes: an imaging lens and a detector; when the dome assembly is illuminated, it is used to illuminate the object to be measured. The dome assembly is located on one side of an optical axis of the imaging assembly and is recessed in a direction away from the optical axis. The imaging lens is used for collecting light reflected and/or scattered by the object to be detected and providing the light to the detector; the detector is used for forming a detection image of the object to be detected according to the light collected by the imaging lens. Because the dome assembly can provide very rich illumination directions, various types of areas of the object to be detected can be subjected to rich illumination, and imaging detection is facilitated on the various types of areas. Therefore, the detection accuracy of the object to be detected is improved, the angle of the object to be detected is prevented from being adjusted or the irradiation angle is prevented from being changed, and the detection efficiency and the detection quantity are improved.
Description
Technical Field
The application relates to the technical field of detection and illumination, in particular to a detection device and a detection method.
Background
In the technical fields of semiconductors, terminals and the like, the method has higher requirements on the morphology of products, so that strict detection is required. When the appearance of the object to be detected is detected, if the ambient light is weak, the object to be detected is usually required to be illuminated. Taking the wafer as an example, the wafer generally includes a flat region (flat), a sloped region (bevel), and an open region (notch).
At present, when a wafer is detected, bright field illumination with oblique incidence is often carried out on the wafer. However, this illumination method is difficult to irradiate the opening area, and thus it is difficult to accurately detect the opening area of the wafer. In addition, it is also difficult to provide sufficient light to the transition region between the flat region and the sloped region, which can easily result in data incoherence in detection. In this way, the detection amount is reduced, and the detection accuracy is low.
Disclosure of Invention
Based on the above problems, the application provides a detection device and a detection method, so as to improve the detection accuracy and the detection quantity of an object to be detected.
The embodiment of the application discloses the following technical scheme:
In a first aspect, the present application provides a detection device comprising: an illumination assembly and an imaging assembly; the lighting assembly comprises: a dome assembly; the imaging assembly includes: an imaging lens and a detector;
the dome assembly is used for illuminating the object to be detected when being lightened; the dome assembly is positioned on one side of an optical axis of the imaging assembly, and the dome assembly is recessed toward a direction away from the optical axis;
the imaging lens is used for collecting light reflected and/or scattered by the object to be detected and providing the light to the detector;
the detector is used for forming a detection image of the object to be detected according to the light collected by the imaging lens.
Optionally, the dome assembly is part of a sphere, the sphere center of the dome assembly being located on the optical axis of the imaging assembly.
Optionally, an intersection point of an optical axis of an imaging component and a focal plane of the imaging component is an imaging field of view center of the imaging component; the distance between the center of the imaging view field and the center of the sphere is less than or equal to half of the thickness of the object to be detected.
Optionally, the light emitting spherical radius of the dome assembly is in the interval 40mm to 60mm, and the angle of the dome assembly at the sagittal plane is in the interval 90 ° to 150 °.
Optionally, the lighting assembly further comprises: a coaxial assembly; the coaxial assembly includes: a coaxial light source; the imaging component further comprises a beam splitter, wherein light emitted by the coaxial light source reaches the surface of the object to be detected after being reflected by the beam splitter, and light returned by the object to be detected reaches the detector after being transmitted by the beam splitter; or the light emitted by the coaxial light source reaches the surface of the object to be detected after being transmitted by the beam splitter, and the light returned by the object to be detected reaches the detector after being reflected by the beam splitter; .
Optionally, the coaxial light source is a fiber optic light source or an LED light source.
Optionally, the light emitted by the coaxial light reaches the surface of the object to be detected after being reflected by the beam splitter, and the light returned by the object to be detected reaches the detector after being transmitted by the beam splitter; the coaxial assembly further comprises: and the extinction element is used for absorbing the light emitted by the coaxial light source and transmitted by the beam splitter.
Optionally, the fiber optic light source includes: the light-emitting surface of the coupling optical fiber is positioned at a first focal plane of the coupling lens, and at least one point on the surface of the object to be detected is positioned at a second focal plane of the coupling lens.
Optionally, the focal length of the coupling lens is greater than the working distance of the imaging lens.
Optionally, the lighting assembly further comprises: the first lighting assembly; when the first illumination component is lightened, the first illumination component is used for carrying out dark field illumination on the object to be detected; the light emergent direction of the first illumination assembly and the optical axis of the imaging assembly form an acute included angle.
Optionally, the first lighting assembly comprises: a first sub-assembly, a second sub-assembly; the light emergent directions of the first subassembly and the second subassembly are different.
Optionally, the light emitting direction of the first subassembly, the light emitting direction of the second subassembly and the optical axis of the imaging assembly are located on the same plane, and the light emitting direction of the first subassembly and the light emitting direction of the second subassembly are symmetrical with respect to the optical axis of the imaging assembly; the dome assembly is located on one side of the plane.
Optionally, the first subassembly and the second subassembly are each a fiber optic light source.
In a second aspect, the present application provides a detection method, using any one of the detection devices of the first aspect, the method comprising:
Illuminating a region to be measured of the object to be measured by utilizing the illumination assembly;
Collecting light reflected and/or scattered by the object to be detected by using the imaging lens and providing the light to the detector;
and forming a detection image of the object to be detected by using the detector according to the light collected by the imaging lens.
Optionally, an intersection point of an optical axis of an imaging component and a focal plane of the imaging component is an imaging field of view center of the imaging component; the distance between the center of the imaging view field and the sphere center of the sphere where the dome assembly is located is smaller than or equal to the thickness of the object to be detected;
before illuminating the area to be measured of the object to be measured with the illumination assembly, the method further includes: and enabling the to-be-detected area of the to-be-detected object to cover the center of the imaging view field.
Optionally, the object to be measured is a wafer to be measured, and the area to be measured is an edge area of the wafer to be measured; the edge area of the wafer to be tested comprises: a flat region, an inclined region, and an opening region;
the illuminating module is used for illuminating the region to be detected of the object to be detected, and specifically comprises one or a combination of the following steps:
the coaxial assembly, the dome assembly and the first illumination assembly are lightened, and the flat area, the inclined area and the opening area are subjected to imaging detection through the detection device, so that bright field images of the flat area, the inclined area and the opening area are obtained;
the coaxial assembly is lightened, the flat area is subjected to imaging detection through the detection device to obtain bright field images of the flat area, and the inclined area and the opening area are subjected to imaging detection to obtain dark field images of the inclined area and the opening area;
The dome assembly is lightened, the inclined area and the opening area are detected and imaged through the detection device, bright field images of the inclined area and the opening area are obtained, imaging detection is carried out on the flat area, and dark field images of the flat area are obtained;
Illuminating the coaxial assembly and the first illumination assembly, and performing imaging detection on the inclined area and the opening area through the detection device to obtain dark field images of the inclined area and the opening area; and the dome assembly and the first illumination assembly are lightened, the flat area is subjected to imaging detection through the detection device, and a dark field image of the flat area is obtained.
Compared with the prior art, the application has the following beneficial effects:
The detection device provided by the application comprises: an illumination assembly and an imaging assembly; the lighting assembly includes: a dome assembly; the imaging assembly includes: an imaging lens and a detector; when the dome assembly is illuminated, it is used to illuminate the object to be measured. The dome assembly is located on one side of an optical axis of the imaging assembly and is recessed in a direction away from the optical axis. The imaging lens is used for collecting light reflected and/or scattered by the object to be detected and providing the light to the detector; the detector is used for forming a detection image of the object to be detected according to the light collected by the imaging lens. Because the dome assembly can provide very rich illumination directions, various types of areas of the object to be detected can be subjected to rich illumination, and imaging detection is facilitated on the various types of areas. Therefore, the detection accuracy of the object to be detected is improved, the angle of the object to be detected is prevented from being adjusted or the irradiation angle is prevented from being changed, and the detection efficiency and the detection quantity are improved.
Drawings
In order to more clearly illustrate the embodiments of the application or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the application, and that other drawings can be obtained according to these drawings without inventive faculty for a person skilled in the art.
Fig. 1 is a schematic structural diagram of a detection device on a meridian plane according to an embodiment of the present application;
FIG. 2 is a schematic diagram of a structure of a detecting device on a sagittal plane according to an embodiment of the present application;
Fig. 3 is a schematic structural diagram of another detection device provided in an embodiment of the present application on a meridian plane;
FIG. 4 is a schematic diagram of an internal structure of a dark field optical fiber according to an embodiment of the present application;
Fig. 5 is a schematic perspective view of a detecting device for detecting an edge of a wafer according to an embodiment of the present application;
FIG. 6 is a top view of the three-dimensional structure of FIG. 5;
FIG. 7 is a schematic view of a wafer flat, sloped, and open regions;
FIG. 8 is a schematic diagram of a test apparatus for illuminating and imaging a flat region, an open region, and a sloped region of a wafer according to an embodiment of the present application;
fig. 9 is a flowchart of a detection method according to an embodiment of the present application.
Detailed Description
As described above, the current detection device is difficult to provide sufficient light for various types of areas of the object to be detected, resulting in lower detection amount and poor detection accuracy. Based on this problem, the inventors have studied and have provided a detection apparatus and a detection method in the present application. In the detection device, the dome assembly is used as the illumination assembly to illuminate the object to be detected, and can provide very rich illumination directions for the object to be detected, so that sufficient illumination conditions are conveniently provided for detection of various areas of the object to be detected, and detection quantity and detection accuracy are improved.
In order to make the present application better understood by those skilled in the art, the following description will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
Device embodiment
The detection device provided by the application comprises: an illumination assembly and an imaging assembly. The illumination assembly is used for illuminating the object to be detected, and the imaging assembly is used for imaging and detecting the object to be detected under the illumination condition provided by the illumination assembly. The detection device is described in detail below with reference to the accompanying drawings.
Referring to fig. 1, the structure of a detection device on a meridian plane according to an embodiment of the present application is shown. Fig. 2 is a schematic diagram of the structure of the detecting device shown in fig. 1 in a sagittal plane. In the detection device shown in fig. 1 and 2, the illumination assembly includes: a dome assembly 100; the imaging assembly includes: an imaging lens 200 and a detector 300.
The dome assembly 100 is located at one side of the optical axis of the imaging assembly, and the dome assembly is recessed towards a direction away from the optical axis, so that the imaging lens 200 can image an object to be detected located in the field of view of the imaging lens 200 without interference and obstruction of the dome assembly 100 without opening holes in the dome assembly 100. To ensure brightness uniformity of imaging, the imaging lens 200 may specifically be an object-side telecentric lens.
When the dome assembly 200 is illuminated, it is used to illuminate the object to be measured. Since the dome assembly 100 can provide light in a variety of illumination directions, a variety of types of areas of the object to be measured can be illuminated.
The imaging lens 200 is used for collecting light reflected and/or scattered by the object to be measured, and providing the light beam to the detector 300 after refracting the light beam.
The detector 300 may be a photoelectric detector for performing photoelectric conversion to form a detection image of the object to be detected.
In the embodiment of the present application, since the dome assembly 100 can provide a very rich illumination direction, a plurality of types of regions of the object to be measured can be subjected to rich illumination, so that imaging detection can be conveniently performed on the plurality of types of regions. Therefore, the detection accuracy of the object to be detected is improved, the angle of the object to be detected is prevented from being adjusted or the irradiation angle is prevented from being changed, and the detection efficiency and the detection quantity are improved.
The dome assembly 100 may be implemented in a variety of ways. In one possible implementation, the dome assembly 100 is a portion of a sphere, such as a quarter or a sixth of a sphere. When the dome assembly 100 is part of a sphere, each light emitting location of the dome assembly 100 emits light specifically toward the center of the sphere in which the dome assembly 100 is located. In an embodiment of the present application, the dome assembly 100 and the imaging lens 200 may be installed as follows:
The center of the sphere of the dome assembly 100 is located on the optical axis of the imaging assembly, i.e., the optical axis of the imaging assembly passes through the center of the sphere in which the dome assembly 100 is located.
When the object to be detected is detected, the object to be detected is placed on a working plane, the upper surface of the object to be detected is coincident with the focal plane of the imaging assembly, and the intersection point of the optical axis of the imaging assembly and the focal plane of the imaging assembly is the center of an imaging view field of the imaging assembly. In practical applications, the distance between the center of the imaging field of view and the center of the sphere is very close, and for a relatively thin object to be measured, the center of the sphere and the center of the imaging field of view may coincide. For an object to be measured with a certain thickness, the sphere center can be positioned in the center of the thickness of the object to be measured, namely, the distance between the sphere center and the center of the imaging view field is half of the thickness of the object to be measured. Therefore, in practical application, the distance between the center of the sphere and the center of the imaging field of view is less than or equal to half the thickness of the object to be measured.
In one possible implementation, the dome assembly 100 has a luminous spherical radius between 40mm and 60mm, for example 50mm; the angle of the dome assembly 100 at the sagittal plane is between 90 deg. and 150 deg., for example 120 deg., as shown in fig. 2.
In the detection device provided by the embodiment of the application, the illumination assembly further comprises: a coaxial assembly. The coaxial assembly includes: the coaxial light source, the imaging assembly further includes a beam splitter. Including the following two possibilities:
(1) Light emitted by the coaxial light source reaches the surface of the object to be detected after being reflected by the beam splitter, and light returned by the object to be detected reaches the detector 300 after being transmitted by the beam splitter.
(2) Light emitted by the coaxial light source reaches the surface of the object to be detected after being transmitted by the beam splitter, and light returned by the object to be detected reaches the detector 300 after being reflected by the beam splitter.
The two cases (1) and (2) can be regarded as the respective optical path transfer directions after the positions of the coaxial light source and the imaging component are mutually replaced. The device layout of case (1) is only schematically shown in the figure. The optical axis of the imaging assembly refers specifically to the central axis of the light beam collected by the imaging assembly. The elements of the detector 300 to the object under test on the collection path are part of the imaging assembly and therefore the beam splitter is also part of the imaging assembly.
In (1), the object to be measured is illuminated with the reflected light beam, and in this scenario, the reflected light beam split by the beam splitter is coaxial with the optical axis of the imaging assembly.
In (2), the object to be measured is illuminated with the transmitted beam, and in this scenario, the transmitted beam split by the beam splitter is coaxial with the optical axis of the imaging assembly.
The coaxial assembly may also be referred to as an outer coaxial light source, also for illumination. The coaxial assembly is particularly adapted for brightfield illumination of an object to be measured when illuminated. The coaxial light source may in particular be a fiber optic light source or an LED light source.
Two implementations of the coaxial assembly are described below in conjunction with the accompanying drawings.
Referring to fig. 1 and 2, a first implementation of the coaxial assembly is shown from two perspectives, respectively. In a first implementation, a coaxial assembly includes: a lamp box (not shown), a coupling optical fiber 400, a coupling lens 500, a first spectroscopic element 600, and a first extinction element 700.
One end of the coupling optical fiber 400 is optically connected to the lamp box, and the other end is optically connected to the coupling lens 500. The coupling optical fiber 400 transmits light provided from the lamp box to the coupling lens 500.
The first beam splitter 600 is used for receiving the light beam passing through the coupling lens 500. The first light splitting element 600 is configured to reflect and transmit the received light beam, the reflected light is emitted to the object to be measured, and the transmitted light is emitted to the first extinction element 700. The first extinction element 700 is located on a side of the first light-splitting element 600 through which the light beam is transmitted, and specifically, the first extinction element 700 may be closely attached to the side of the first light-splitting element 600 through which the light beam is transmitted. The first extinction element 700 is configured to absorb and cancel light received (i.e., transmitted light from the first light splitting element 600).
In one possible implementation, the light emitting surface of the coupling fiber 400 is located at a first focal plane of the coupling lens 500, and at least one point of the surface of the object to be measured is located at a second focal plane of the coupling lens 500. The first focal plane is a front focal plane of the coupling lens 500, and the second focal plane is a back focal plane of the coupling lens 500. By adopting the Kohler illumination mode, higher illumination uniformity can be obtained, and the illumination uniformity is not affected by dirt or processing flaws on the luminous surface of the optical fiber.
The focal length of the coupling lens 500 is greater than the working distance of the imaging lens 200, and the difference between the focal length of the coupling lens 500 and the working distance of the imaging lens 200 is less than a preset second threshold. This facilitates the layout of the components within the inspection apparatus.
Fig. 3 is a schematic structural diagram of another detection device provided in an embodiment of the present application on a meridian plane. The figure illustrates a second implementation of the coaxial assembly. As shown, the coaxial assembly includes: a bright field light emitting diode 800, a second light splitting element 900 and a second extinction element 1000. The second spectroscopic element 900 has substantially the same function as the first spectroscopic element 600, and has both reflection and refraction functions.
The light beam emitted from the bright field light emitting diode 800 is split by the second splitting element 900, wherein the reflected light is provided to the object to be measured, and the transmitted light is provided to the second extinction element 1000. The second matting element 1000 functions substantially the same as the first matting element 700. Specifically, the second extinction element 1000 may be close to a surface of the second light splitting element 900 through which the light beam is transmitted. The second light extinction element 1000 is operative to absorb and eliminate received light (i.e., transmitted light from the second light splitting element 900).
The first and second beam splitter 600 and 900 may be beam splitters or beam splitters. The light splitting ratio of the first light splitting element 600 and the second light splitting element 900 may be 50%:50%, i.e. semi-reflective semi-transmissive. This allows a higher light efficiency to be obtained.
The optical axis of the coaxial assembly is coaxial with the optical axis of the imaging assembly. In the first and second implementations of the coaxial assembly, since the reflection and transmission effects of the first and second light-splitting elements 600 and 900 can be known, the reflected light is specifically provided to the object to be measured for illumination, and thus the optical axis is specifically that the optical axis of the reflected light path from the coaxial assembly to the object to be measured is coaxial with the optical axis of the imaging assembly. That is, in the first implementation, the optical axis of the optical path from the first spectroscopic element 600 to the object to be measured is coaxial with the optical axis of the imaging module; in the second implementation, the optical axis of the optical path from the second beam splitter 900 to the object is coaxial with the optical axis of the imaging component.
In a second implementation manner of the coaxial assembly, the bright field light emitting diode 800 is used as a light source in the coaxial assembly, so that the integration level of the illumination assembly part in the provided detection device is improved, and the whole volume of the detection device is reduced.
In some cases, it is also necessary to perform dark-field illumination and dark-field detection of the object to be measured by means of the detection device. For this reason, in the detection device provided by the embodiment of the present application, the lighting assembly may further include a first lighting assembly. When the first illumination assembly is lighted, the first illumination assembly is used for dark field illumination of the object to be measured.
In an embodiment of the present application, in order to perform sufficient dark field illumination on a detected area of an object to be detected, the first illumination assembly may provide at least two different illumination directions. For example, the first illumination assembly may include at least two lights providing different illumination directions, with the light exiting direction of the first illumination assembly having an acute included angle with the optical axis of the imaging assembly. The first lighting assembly may be a fiber optic light source or an LED light source.
The first lighting assembly may include a first sub-assembly and a second sub-assembly, which in the examples below are both fiber optic light sources.
In one possible implementation, the first illumination assembly includes a first dark field optical fiber 301 and a second dark field optical fiber 302 as shown in fig. 3. The first dark field optical fiber 301 and the second dark field optical fiber 302 may be connected to a dark field light box (not shown in the figure), wherein a first end of the optical fiber is optically connected to the dark field light box, and a second end is used for emitting a light beam to a surface of the object to be measured. The illumination direction provided by the first dark field optical fiber 301 to the object to be measured is different from the illumination direction provided by the second dark field optical fiber 302 to the object to be measured.
The first dark field optical fiber 301 and the second dark field optical fiber 302 may be connected to the same dark field light box, e.g. the dark field light box comprises two output ports, which are connected to different dark field optical fibers, respectively. In addition, the first dark field optical fiber 301 and the second dark field optical fiber 302 may also be connected to different dark field light boxes, respectively. For example, a first end of the first dark field fiber 301 is optically connected to a first light box (not shown), and a first end of the second dark field fiber 302 is optically connected to a second light box (not shown).
The light box to which the first dark field optical fiber 301 and the second dark field optical fiber 302 are connected may have different spectral divisions, for example 1 blue, 1 green light box. And flexibly adjusting according to different wafer processes. Different wafer processes result in different surface optical reflection characteristics: spectral reflectance differences, surface roughness differences, overall reflectance, etc. That is, in practical application, a suitable processing technology may be selected to process the wafer according to the requirement of the optical reflection characteristic, or a suitable light box with a spectrum may be selected according to the processing technology of the wafer. Thus, the desired illumination and detection effect is achieved.
Fig. 4 illustrates an internal structural diagram of a dark field fiber. As can be seen from fig. 4, the dark field optical fiber has a cylindrical mirror inside, and the light emitting surface of the optical fiber is imaged on the wafer surface, so that the highest illuminance is obtained. The optical axes of the first and second dark field fibers 301, 302, respectively, may be coplanar with the illumination optical axis of the coaxial assembly (or the optical axis of the imaging assembly, or the imaging optical path). Optionally, the optical axes of the first and second dark field fibers 301, 302 are at an acute angle, e.g., 70 ° angle, to the optical axis of the imaging assembly.
In one possible implementation, the power of the first lighting assembly is higher than the power of the on-axis assembly, so the first lighting assembly may provide a high brightness dark field lighting condition.
In one possible implementation, the imaging lens 200 is operated at a distance of 110mm, and the overall dimensions of the coaxial assembly and the dome assembly in the direction of the optical axis do not exceed 110mm. Meanwhile, considering the safety of upper and lower pieces of an object to be measured (such as a wafer), the illumination distances of the first dark field optical fiber 301 and the second dark field optical fiber 302 are 70mm, and the minimum distance between the structures of the first dark field optical fiber 301 and the second dark field optical fiber 302 and the object to be measured is larger than 24mm. If the object is a wafer, the center of the field of view of the imaging lens 200 is located 147.5mm from the center of the wafer in this embodiment.
In this embodiment, the detector 300 in the detecting device is a 3-line true color line scanning detector, the length of the line scanning array is perpendicular to the plane shown in fig. 1, and the scanning direction is the horizontal direction shown in fig. 1. The wafer rotates by taking the center of the circle as the center, and the line scanning camera can image the edge of the wafer completely. Therefore, the effect of high-speed acquisition can be achieved, the obtained image is a true color RGB image, multispectral defect identification can be conveniently carried out in the later stage, and the identification rate is improved. According to the scanning direction of the line scanning camera, the meridian plane of bright field illumination is preferably coincident with the cross section of the dome assembly, so that the imaging uniformity is ensured.
Fig. 5 is a schematic perspective view of a detecting device for detecting an edge of a wafer according to an embodiment of the present application. Fig. 6 is a top view of the three-dimensional structure shown in fig. 5. In addition, the first lighting assembly may also be a ring LED light source.
For a scenario in which a wafer is used as an object to be measured, the wafer to be measured includes: flat, sloped, and open regions of various types. Fig. 7 is a schematic view of a wafer flat, sloped, and open regions. In order to achieve illumination and detection of multiple types of regions, different combinations of illumination assemblies may be used for illumination, respectively.
The detection device is used for carrying out bright field illumination and imaging detection on the flat area, the inclined area and the opening area when the coaxial assembly, the dome assembly and the first illumination assembly are simultaneously lightened;
The detection device is used for carrying out bright field illumination and imaging detection on the flat area and carrying out dark field illumination and imaging detection on the inclined area and the opening area when only the coaxial assembly is lighted;
the detection device is used for carrying out bright field illumination and imaging detection on the inclined area and the opening area and carrying out dark field illumination and imaging detection on the flat area when only the dome assembly is lightened;
the detection device is used for carrying out dark field illumination and imaging detection on the inclined area and the opening area when the coaxial assembly and the first illumination assembly are simultaneously lightened;
the detection device is used for dark field illumination and imaging detection of the flat area when the dome assembly and the first illumination assembly are illuminated simultaneously.
According to the illumination and detection requirements of different areas of the detected object, the 5 illumination working schemes are adjusted according to actual conditions, and the combination scheme is optimized, so that the effects of highest detection speed and highest defect detection sensitivity can be achieved. Fig. 8 is a schematic diagram of a simulation of illumination and imaging of a flat region, an open region, and an inclined region of a wafer using a detection apparatus according to an embodiment of the present application. As can be seen from fig. 8, the above-mentioned illumination assembly is used for illumination, so that illumination of various areas of the wafer can be covered, and effective detection of the wafer can be realized.
Method embodiment
Based on the device embodiment provided by the previous embodiment, the application correspondingly provides a detection method. As shown in fig. 9, the figure is a flow chart of a detection method. The method specifically comprises the step of utilizing the detection device provided by the device embodiment to realize illumination and detection.
The detection method shown in fig. 9 includes:
step 901: illuminating a region to be measured of the object to be measured by utilizing the illumination assembly;
Step 902: collecting light reflected and/or scattered by the object to be detected by using the imaging lens and providing the light to the detector;
Step 903: and forming a detection image of the object to be detected by using the detector according to the light collected by the imaging lens.
Because the dome assembly can provide very rich illumination directions, various types of areas of the object to be detected can be subjected to rich illumination, and imaging detection is facilitated on the various types of areas. Therefore, the detection accuracy of the object to be detected is improved, the angle of the object to be detected is prevented from being adjusted or the irradiation angle is prevented from being changed, and the detection efficiency and the detection quantity are improved.
The intersection point of the optical axis of the imaging component and the focal plane of the imaging component is the center of the imaging field of view of the imaging component; the distance between the center of the imaging view field and the sphere center of the sphere where the dome assembly is located is smaller than or equal to the thickness of the object to be detected;
before the step S901 is performed, the method may further include: and enabling the to-be-detected area of the to-be-detected object to cover the center of the imaging view field.
If the object to be measured is a wafer to be measured, the area to be measured of the object to be measured is an edge area of the wafer, and the edge area of the wafer to be measured comprises: a flat region, an inclined region, and an opening region;
step 901 may specifically include one or a combination of steps of:
the coaxial assembly, the dome assembly and the first illumination assembly are lightened, and the flat area, the inclined area and the opening area are subjected to imaging detection through the detection device, so that bright field images of the flat area, the inclined area and the opening area are obtained;
the coaxial assembly is lightened, the flat area is subjected to imaging detection through the detection device to obtain bright field images of the flat area, and the inclined area and the opening area are subjected to imaging detection to obtain dark field images of the inclined area and the opening area;
The dome assembly is lightened, the inclined area and the opening area are detected and imaged through the detection device, bright field images of the inclined area and the opening area are obtained, imaging detection is carried out on the flat area, and dark field images of the flat area are obtained;
Illuminating the coaxial assembly and the first illumination assembly, and performing imaging detection on the inclined area and the opening area through the detection device to obtain dark field images of the inclined area and the opening area; and the dome assembly and the first illumination assembly are lightened, the flat area is subjected to imaging detection through the detection device, and a dark field image of the flat area is obtained.
It should be noted that, in the present specification, each embodiment is described in a progressive manner, and identical and similar parts of each embodiment are all referred to each other, and each embodiment is mainly described in a different point from other embodiments. In particular, for the apparatus and system embodiments, since they are substantially similar to the method embodiments, the description is relatively simple, with reference to the description of the method embodiments in part. The above-described apparatus and system embodiments are merely illustrative, in which elements illustrated as separate elements may or may not be physically separate, and elements illustrated as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art will understand and implement the present invention without undue burden.
The foregoing is only one specific embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the technical scope of the present application should be included in the scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims (14)
1. A detection apparatus, characterized by comprising: an illumination assembly and an imaging assembly; the lighting assembly comprises: a dome assembly; the imaging assembly includes: an imaging lens and a detector;
When the dome assembly is lighted, the dome assembly is used for illuminating an object to be detected; the dome assembly is positioned on one side of an optical axis of the imaging assembly, and the dome assembly is recessed toward a direction away from the optical axis; the dome assembly is a part of a sphere, and the sphere center of the dome assembly is positioned on the optical axis of the imaging assembly;
The intersection point of the optical axis of the imaging component and the focal plane of the imaging component is the center of the imaging field of view of the imaging component; the distance between the center of the imaging view field and the center of the sphere is less than or equal to half of the thickness of the object to be detected;
the imaging lens is used for collecting light reflected and/or scattered by the object to be detected and providing the light to the detector;
the detector is used for forming a detection image of the object to be detected according to the light collected by the imaging lens.
2. The detection device of claim 1, wherein the dome assembly has a luminous spherical radius in the interval 40mm to 60mm and an angle in the sagittal plane in the interval 90 ° to 150 °.
3. The detection apparatus according to claim 1 or 2, wherein the illumination assembly further comprises: a coaxial assembly; the coaxial assembly includes: a coaxial light source; the imaging component further comprises a beam splitter, wherein light emitted by the coaxial light source reaches the surface of the object to be detected after being reflected by the beam splitter, and light returned by the object to be detected reaches the detector after being transmitted by the beam splitter; or the light emitted by the coaxial light source reaches the surface of the object to be detected after being transmitted by the beam splitter, and the light returned by the object to be detected reaches the detector after being reflected by the beam splitter.
4. A detection device according to claim 3, wherein the coaxial light source is a fiber optic light source or an LED light source.
5. A detection device according to claim 3, wherein the light emitted from the coaxial light source reaches the surface of the object to be detected after being reflected by the beam splitter, and the light returned by the object to be detected reaches the detector after being transmitted by the beam splitter; the coaxial assembly further comprises: and the extinction element is used for absorbing the light emitted by the coaxial light source and transmitted by the beam splitter.
6. The detection apparatus of claim 4, wherein the fiber optic light source comprises: the light-emitting surface of the coupling optical fiber is positioned at a first focal plane of the coupling lens, and at least one point on the surface of the object to be detected is positioned at a second focal plane of the coupling lens.
7. The detection apparatus according to claim 6, wherein a focal length of the coupling lens is larger than a working distance of the imaging lens.
8. A detection device according to claim 3, wherein the illumination assembly further comprises: a first lighting assembly; when the first illumination assembly is lightened, the first illumination assembly is used for illuminating the object to be detected; the light emergent direction of the first illumination assembly and the optical axis of the imaging assembly form an acute included angle.
9. The detection apparatus of claim 8, wherein the first illumination assembly comprises: a first sub-assembly, a second sub-assembly; the light emergent directions of the first subassembly and the second subassembly are different.
10. The detection device of claim 9, wherein the light exit direction of the first subassembly, the light exit direction of the second subassembly, and the optical axis of the imaging assembly are in the same plane, and the light exit direction of the first subassembly and the light exit direction of the second subassembly are symmetrical about the optical axis of the imaging assembly; the dome assembly is located on one side of the plane.
11. The test device of claim 9, wherein the first subassembly and the second subassembly are each fiber optic light sources.
12. A detection method, characterized in that the detection device according to any one of claims 8 to 11 is applied, the method comprising:
Illuminating a region to be measured of the object to be measured by utilizing the illumination assembly;
Collecting light reflected and/or scattered by the object to be detected by using the imaging lens and providing the light to the detector;
and forming a detection image of the object to be detected by using the detector according to the light collected by the imaging lens.
13. The method of claim 12, wherein an intersection of an optical axis of the imaging assembly and a focal plane of the imaging assembly is a center of an imaging field of view of the imaging assembly; the distance between the center of the imaging view field and the sphere center of the sphere where the dome assembly is located is less than or equal to half of the thickness of the object to be detected;
before illuminating the area to be measured of the object to be measured with the illumination assembly, the method further includes: and enabling the to-be-detected area of the to-be-detected object to cover the center of the imaging view field.
14. The inspection method according to claim 12 or 13, wherein the object to be inspected is a wafer to be inspected, and the area to be inspected is an edge area of the wafer to be inspected; the edge area of the wafer to be tested comprises: a flat region, an inclined region, and an opening region;
the illuminating module is used for illuminating the region to be detected of the object to be detected, and specifically comprises one or a combination of the following steps:
the coaxial assembly, the dome assembly and the first illumination assembly are lightened, and the flat area, the inclined area and the opening area are subjected to imaging detection through the detection device, so that bright field images of the flat area, the inclined area and the opening area are obtained;
the coaxial assembly is lightened, the flat area is subjected to imaging detection through the detection device to obtain bright field images of the flat area, and the inclined area and the opening area are subjected to imaging detection to obtain dark field images of the inclined area and the opening area;
The dome assembly is lightened, the inclined area and the opening area are detected and imaged through the detection device, bright field images of the inclined area and the opening area are obtained, imaging detection is carried out on the flat area, and dark field images of the flat area are obtained;
Illuminating the coaxial assembly and the first illumination assembly, and performing imaging detection on the inclined area and the opening area through the detection device to obtain dark field images of the inclined area and the opening area; and the dome assembly and the first illumination assembly are lightened, the flat area is subjected to imaging detection through the detection device, and a dark field image of the flat area is obtained.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6552783B1 (en) * | 2000-06-28 | 2003-04-22 | Teradyne, Inc. | Optical system |
| TW200935041A (en) * | 2007-10-31 | 2009-08-16 | Canon Kk | Measurement apparatus, exposure apparatus, and device manufacturing method |
| TW201018895A (en) * | 2008-11-07 | 2010-05-16 | Utechzone Co Ltd | Detection device and method of obtaining detection image |
| CN102878956A (en) * | 2012-10-22 | 2013-01-16 | 中国科学院光电技术研究所 | Measuring device for central error based on equal-thickness interference method |
| CN202757891U (en) * | 2012-07-30 | 2013-02-27 | 由田新技股份有限公司 | Observation system |
| WO2014036120A1 (en) * | 2012-08-28 | 2014-03-06 | Kla-Tencor Corporation | Multi directional illumination for a microscope and microscope |
| CN110658198A (en) * | 2018-06-29 | 2020-01-07 | 由田新技股份有限公司 | Optical detection method, optical detection device and optical detection system |
-
2020
- 2020-08-24 CN CN202010857187.2A patent/CN114184138B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6552783B1 (en) * | 2000-06-28 | 2003-04-22 | Teradyne, Inc. | Optical system |
| TW200935041A (en) * | 2007-10-31 | 2009-08-16 | Canon Kk | Measurement apparatus, exposure apparatus, and device manufacturing method |
| TW201018895A (en) * | 2008-11-07 | 2010-05-16 | Utechzone Co Ltd | Detection device and method of obtaining detection image |
| CN202757891U (en) * | 2012-07-30 | 2013-02-27 | 由田新技股份有限公司 | Observation system |
| WO2014036120A1 (en) * | 2012-08-28 | 2014-03-06 | Kla-Tencor Corporation | Multi directional illumination for a microscope and microscope |
| CN102878956A (en) * | 2012-10-22 | 2013-01-16 | 中国科学院光电技术研究所 | Measuring device for central error based on equal-thickness interference method |
| CN110658198A (en) * | 2018-06-29 | 2020-01-07 | 由田新技股份有限公司 | Optical detection method, optical detection device and optical detection system |
Non-Patent Citations (1)
| Title |
|---|
| 基于多点光源的金属表面三维缺陷检测方法;徐科;王磊;向境;周鹏;;中国科技论文(第04期);全文 * |
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