Wafer detection device and wafer detection method

Abstract

The invention discloses a wafer detection device and a wafer detection method, and the device comprises a carrying platform which is used for carrying a wafer and carrying out the linear movement, and the wafer is provided with a substrate and a film layer covering the substrate; the first substrate imaging system comprises a first light source module and a first detection module, the first light source module is used for emitting illumination light to the surface of the wafer, and the first detection module is used for collecting a substrate image of the wafer; the first film layer imaging system comprises a second light source module and a second detection module, the second light source module is used for emitting illumination light to the surface of the wafer, and the second detection module is used for collecting a film layer image of the wafer; and the analysis module is electrically connected with the first substrate imaging system and the first film layer imaging system, and is used for analyzing the substrate image to obtain substrate defect information of the wafer and analyzing the film layer image to obtain film layer defect information of the wafer. According to the invention, defect detection can be carried out on the substrate and the surface film layer of the wafer at the same time, and the wafer detection efficiency is improved.

Description

Technical Field

[0001] The present application relates to the field of wafer detection technology, and in particular to a wafer detection device and a wafer detection method. Background Art

[0002] As a core fundamental material in the semiconductor and optoelectronics sectors, wafer processing quality directly impacts the performance of the final product. The complete wafer-to-chip process encompasses key steps such as oxidation, photolithography, grinding, etching, packaging, and testing, many of which harbor potential processing defects that could impact yield. During wafer manufacturing, surface defects often develop and damage the wafer due to contamination from dust, dirt, scratches, particulate matter, and other sources, as well as poor process flow. Furthermore, during grinding and dicing, protective films are applied to the front or back of the wafer for protection. This can lead to blistering defects due to poor adhesion, and the film itself may also harbor structural anomalies such as bumps and pits. These surface defects on the wafer substrate and film layer not only reduce the processing accuracy of the current process but also impact subsequent steps, ultimately severely impacting chip yield and product reliability. Therefore, detecting defects on the wafer surface and film layer is crucial.

[0003] At present, existing wafer inspections mainly include bright field inspection, dark field inspection, or a combination of bright field and dark field inspections. For bright field imaging, due to the transparency of the film layer, the difference in reflectivity between it and the wafer substrate is too large, resulting in the bright field imaging method being able to only capture the reflection signal on the surface of the wafer substrate, while the low reflectivity film layer cannot achieve bright field imaging. For dark field imaging, due to differences in physical properties, the scattered signals formed by the illumination light emitted by the same dark field light source on the wafer substrate and the film layer are different, resulting in the inability to accurately capture the film layer defect information. Therefore, in order to realize the detection of the film layer, it is necessary to add a set of detection devices and a detection process, which greatly reduces the efficiency of wafer detection. Summary of the Invention

[0004] In view of this, the present application provides a wafer inspection device and a wafer inspection method to solve the problem that it is difficult to achieve synchronous inspection of the wafer substrate and film layer in existing wafer inspection.

[0005] To solve the above technical problems, one technical scheme adopted by the present application is to provide a wafer detection device, which comprises: a carrier for loading a wafer and performing linear movement, the wafer having a substrate and a film layer covering the substrate; a first substrate imaging system comprising a first light source module and a first detection module, the first light source module being configured to emit illumination light to the surface of the wafer, and the first detection module being configured to acquire a substrate image of the wafer; a first film layer imaging system comprising a second light source module and a second detection module, the second light source module being configured to emit illumination light to the surface of the wafer, and the second detection module being configured to acquire a film layer image of the wafer; and an analysis module electrically connected to the first substrate imaging system and the first film layer imaging system, and configured to analyze the substrate image to obtain substrate defect information of the wafer, and analyze the film layer image to obtain film layer defect information of the wafer.

[0006] As a further improvement of the present application, the first light source module comprises a first bright field irradiation unit and a first dark field irradiation unit, the first bright field irradiation unit emits first illumination light to the surface of the wafer at a first incident angle, the first dark field irradiation unit emits second illumination light to the surface of the wafer at a second incident angle, and the first detection module is configured to acquire a bright field reflection image or a dark field scattering image of the substrate of the wafer; the second light source module comprises a second dark field irradiation unit, the second dark field irradiation unit emits third illumination light to the surface of the wafer at a third incident angle, and the second detection module is configured to acquire a film layer scattering image of the film layer on the surface of the wafer.

[0007] As a further improvement of the present application, the first bright field irradiation unit and the first dark field irradiation unit each have a corresponding adjustment device, which is configured to adjust at least one of a pitch angle, a horizontal position and a vertical position so that the first incident angle is within a first preset angle range and the second incident angle is within a second preset angle range, and the first preset angle range is smaller than the second preset angle range.

[0008] As a further improvement of the present application, the first detection module comprises a first imaging lens, a first linear array camera and a first camera adjustment device, the first imaging lens is configured to receive reflected light of the first illumination light on the substrate surface of the wafer or scattered light of the second illumination light on the substrate surface of the wafer, and transmit the received light beam to the first linear array camera, and the first camera adjustment device is configured to adjust at least one of a pitch angle, a horizontal position and a vertical position of the first imaging lens so that an optical axis of the first imaging lens is symmetrical to an optical axis of the first bright field irradiation unit about a normal line of the surface of the wafer.

[0009] As a further improvement of the present application, the second dark field irradiation unit has a corresponding adjustment device, which is configured to adjust at least one of a pitch angle, a horizontal position and a vertical position so that the third incident angle is within a third preset angle range, and the third preset angle range is larger than the second preset angle range.

[0010] As a further improvement of the present application, the second detection module comprises a second imaging lens, a second linear array camera and a second camera adjusting device, the second imaging lens is used for receiving the scattered light of the third illumination light on the film layer of the wafer and transmitting the received light beam to the second linear array camera, and the second camera adjusting device is used for adjusting the pitch angle of the second imaging lens.

[0011] As a further improvement of the present application, the first light source module is used for emitting the illumination light of the first preset wavelength which can easily penetrate the film layer to reach the substrate, and the second light source module is used for emitting the illumination light of the second preset wavelength which can easily reflect or scatter on the surface of the film layer.

[0012] As a further improvement of the present application, the carrier comprises a bearing part and a driving part, the bearing part is arranged on the driving part, the bearing part is used for bearing and limiting the wafer, and the driving part is used for driving the bearing part to move to drive the wafer to linearly move.

[0013] As a further improvement of the present application, it further comprises a second substrate imaging system and a second film layer imaging system; the first substrate imaging system and the first film layer imaging system are arranged on one side of the wafer, and the second substrate imaging system and the second film layer imaging system are arranged on the other side of the wafer; the first light source module and the second light source module are both used for emitting the illumination light to the first to-be-detected position on the front surface of the wafer, the first detection module is used for collecting the substrate image at the first to-be-detected position, and the second detection module is used for collecting the film layer image at the first to-be-detected position; the second substrate imaging system comprises a third light source module and a third detection module, the third light source module is used for emitting the illumination light to the second to-be-detected position on the back surface of the wafer, and the third detection module is used for collecting the substrate image at the second to-be-detected position, the projection positions of the first to-be-detected position and the second to-be-detected position on the front surface or the back surface of the wafer are staggered with each other; the second film layer imaging system comprises a fourth light source module and a fourth detection module, the fourth light source module is used for emitting the illumination light to the second to-be-detected position, and the fourth detection module is used for collecting the film layer image at the second to-be-detected position; the analysis module is further electrically connected with the second substrate imaging system and the second film layer imaging system, and the analysis module is further used for analyzing the substrate images and the film layer images of the first to-be-detected position and the second to-be-detected position to obtain the defect information of the substrate and the film layer of the wafer.

[0014] To solve the above technical problems, another technical solution adopted by the present application is to provide a wafer detection method applied to one of the wafer detection devices; the method comprises the following steps: loading the wafer to be detected to the carrier; controlling the first light source module and the second light source module to be turned on, the first light source module and the second light source module emit the illumination light to the surface of the wafer, the carrier drives the wafer to linearly move, the first detection module obtains the substrate image of the wafer, and the second detection module obtains the film layer image of the wafer; and the analysis module analyzes the substrate image to obtain the substrate defect information of the wafer and analyzes the film layer image to obtain the film layer defect information of the wafer.

[0015] As a further improvement of the present application, the first light source module comprises a first bright field illumination unit and a first dark field illumination unit, and the second light source module comprises a second dark field illumination unit; the first light source module and the second light source module are controlled to be turned on, the first light source module and the second light source module emit illumination light to the wafer surface, the wafer is driven to perform linear motion by the stage, the first detection module acquires the substrate image of the wafer, and the second detection module acquires the film layer image of the wafer; the first bright field illumination unit is turned on and emits first illumination light to the wafer surface, and the second dark field illumination unit is turned on and emits third illumination light to the wafer surface; the wafer is driven to perform linear motion by the stage, the first detection module acquires the bright field reflection image of the wafer substrate, and the second detection module acquires the film layer scattering image of the wafer film layer; the first bright field illumination unit and the second dark field illumination unit are turned off, the first dark field illumination unit is turned on and emits second illumination light to the wafer surface; the wafer is driven to move from the dark field imaging position to the bright field imaging position by the stage, and the first detection module acquires the dark field scattering image of the wafer substrate.

[0016] As a further improvement of the present application, the first bright field illumination unit, the first dark field illumination unit and the second dark field illumination unit each have a corresponding adjusting device; after the first bright field illumination unit is turned on and emits first illumination light to the wafer surface, and the second dark field illumination unit is turned on and emits third illumination light to the wafer surface, the adjusting device further adjusts at least one of the pitch angle, the horizontal position and the vertical position of the first bright field illumination unit, so that the first incident angle of the first illumination light is within a first preset angle range; the adjusting device further adjusts at least one of the pitch angle, the horizontal position and the vertical position of the second dark field illumination unit, so that the third incident angle of the third illumination light is within a third preset angle range; after the first dark field illumination unit is turned on and emits second illumination light to the wafer surface, the adjusting device further adjusts at least one of the pitch angle, the horizontal position and the vertical position of the first dark field illumination unit, so that the second incident angle of the second illumination light is within a second preset angle range; the first preset angle range is smaller than the second preset angle range, and the third preset angle range is larger than the second preset angle range.

[0017] As a further improvement of the present application, the first light source module and the second light source module emit illumination light to the wafer surface, including: the first light source module emits illumination light of a first preset wavelength that can easily penetrate the film layer to reach the substrate to the wafer surface, and the second light source module emits illumination light of a second preset wavelength that is easy to be reflected or scattered on the surface of the film layer to the wafer surface.

[0018] The present application has the following beneficial effects: The wafer detection device of the present application is provided with two groups of optical imaging systems of the first substrate imaging system and the first film layer imaging system, and the wafer substrate imaging and the film layer imaging are realized synchronously by the first detection module and the second detection module without interference between the two groups of optical imaging systems, so that the synchronous detection of the wafer substrate and the film layer is realized, and the efficiency of wafer detection is greatly improved. Moreover, the first bright field irradiation unit and the first dark field irradiation unit with different incident angles are arranged, the bright field detection and the dark field detection of the wafer surface are realized, the second dark field irradiation unit with another incident angle is arranged, the dark field detection of the film layer is realized, the multi-channel optical signal separation and the multi-camera cooperative imaging are realized, the imaging interference of the wafer high-reflective substrate to the low-reflective film layer is solved, the synchronous detection of the wafer surface defect and the film layer defect is realized, the wafer defect detection efficiency is improved, and the equipment cost is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 Fig. 1 is a structural schematic diagram of one embodiment of the wafer detection device of the present application; Figure 2 Fig. 1 is a structural schematic diagram of one embodiment of the wafer detection device of the present application; Figure 3 Fig. 1 is a structural schematic diagram of one embodiment of the wafer detection device of the present application; Figure 4 Fig. 1 is a structural schematic diagram of one embodiment of the wafer detection device of the present application; Figure 5 Fig. 1 is a structural schematic diagram of one embodiment of the wafer detection device of the present application; DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0021] The terms "first," "second," and "third" in this application are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features indicated. Therefore, a feature specified as "first," "second," or "third" may explicitly or implicitly include at least one of such features. In the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined. All directional designations in the embodiments of this application (such as up, down, left, right, front, back, etc.) are intended only to illustrate the relative spatial position and movement of components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional designations will also change accordingly. Furthermore, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to such process, method, product, or apparatus.

[0022] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0023] Figure 1 FIG is a schematic diagram of the structure of a wafer inspection device according to an embodiment of the present invention. Figure 1 As shown, the wafer inspection device includes: a carrier 1, a first substrate imaging system 2, a first film layer imaging system 3 and an analysis module 4 (see Figure 2 ).

[0024] The carrier 1 is used for loading a wafer and performing linear movement, and the wafer has a base and a film layer covering the base.

[0025] The first substrate imaging system 2 comprises a first light source module 21 and a first detection module 22, the first light source module 21 is used for emitting illumination light to the wafer surface, and the first detection module 22 is used for collecting the substrate image of the wafer. Specifically, the first substrate imaging system 2 comprises the first light source module 21 and the first detection module 22, the first light source module 21 comprises one light source or two light sources. If it is one light source, the light source can irradiate the wafer surface at a small incident angle (relative to the normal line), and the reflection light signal of the wafer surface is collected by the first detection module 22 for detection, so as to realize bright field detection; or the light source can irradiate the wafer surface at a large incident angle (relative to the normal line), and the scattering light signal of the wafer surface is collected by the first detection module 22 for detection, so as to realize dark field detection. If it is two light sources, the two light sources respectively irradiate the wafer surface at a small incident angle (relative to the normal line) and a large incident angle (relative to the normal line), and the reflection light signal and the scattering light signal of the wafer surface are collected by the first detection module 22, so as to realize the combined detection of bright field and dark field.

[0026] The first film layer imaging system 3 comprises a second light source module 31 and a second detection module 32, the second light source module 31 is used for emitting illumination light to the wafer surface, and the second detection module 32 is used for collecting the film layer image of the wafer. It should be noted that the wafer is usually made of materials such as silicon and gallium arsenide, which has a high reflectivity and can form a strong reflection light signal under the irradiation of light at a small angle, so the wafer substrate can be detected by using the bright field detection method; and for defects (such as scratches and particles) on the wafer surface, scattering signals (such as scattering light of scratches in a fan shape perpendicular to the direction of the scratches, and scattering light of particles in a ring shape) can be formed under the irradiation of light at a large angle, which is more conducive to identifying whether there is a defect and the specific type, so the wafer substrate can also be detected by using the dark field detection method. The film layer on the wafer surface is usually made of transparent epoxy resin / photoresist and other materials, which has a low reflectivity and is difficult to form an effective reflection light signal under the irradiation of a light source, so the bright field detection is not suitable for defect detection of the film layer; if the dark field detection is used, due to the difference in physical properties between the wafer and the film layer, the scattering signal intensity difference between the two is huge, the substrate defect produces strong directional scattering (such as the reflection of scratches at a specific angle), and the scattering signal is strong, while the light scattering of the film layer bubble and other defects is almost isotropic, and the scattering signal is weak. When the strong scattering signal (substrate scattering) and the weak scattering signal (film layer scattering) coexist, the setting of the camera parameters can only meet the collection needs of one of them, thereby leading to the distortion of the signal data of the other, and further affecting the final detection result. In view of this, the wafer detection device provided in the embodiment of the application adopts two independent imaging systems, the first substrate imaging system 2 is used for realizing imaging of the wafer substrate, and the first film layer imaging system 3 is used for realizing imaging of the film layer.

[0027] Analysis module 4 is electrically connected to first substrate imaging system 2 and first film layer imaging system 3, and is configured to analyze substrate images to obtain substrate defect information of the wafer, and to analyze film layer images to obtain film layer defect information of the wafer. Specifically, analysis module 4 is configured to receive substrate images transmitted by first substrate imaging system 2 and film layer images transmitted by first film layer imaging system 3, and then analyze the substrate images and film layer images, respectively, to obtain substrate defect information and film layer defect information of the wafer.

[0028] Specifically, when using the wafer detection device to detect the wafer, the wafer is first placed on the carrier 1 and fixed, and then the first light source module 21 of the first substrate imaging system 2 and the second light source module 31 of the first film layer imaging system 3 are turned on. The carrier 1 then drives the wafer to perform linear motion. During the movement of the wafer, the first detection module 22 collects the substrate image of the wafer under the illumination of the first light source module 21, and the second detection module 32 collects the film layer image of the wafer under the illumination of the second light source module 31. Finally, the substrate image and the film layer image are sent to the analysis module 4 for analysis to obtain the wafer detection result.

[0029] The wafer inspection device of this embodiment respectively sets up two groups of optical imaging systems, namely the first substrate imaging system 2 and the first film layer imaging system 3. When the two groups of optical imaging systems do not interfere with each other, the first detection module 22 and the second detection module 32 are used to synchronously realize wafer substrate imaging and film layer imaging, thereby realizing synchronous detection of the wafer substrate and film layer, greatly improving the efficiency of wafer inspection.

[0030] Furthermore, in this embodiment, the first light source module 21 is used to emit illumination light of a first preset wavelength that is easy to penetrate the film layer and reach the substrate, and the second light source module 31 is used to emit illumination light of a second preset wavelength that is easy to be reflected or scattered on the surface of the film layer.

[0031] Specifically, when selecting the first light source module 21, it is preferred to choose a light source with strong penetration and good reflection effect on the substrate. For example, for silicon wafers, a light source with a wavelength range of 800-1100 nm can be used. When selecting the second light source module 31, it is preferred to choose a wavelength with a large scattering cross-section of the film material (such as a light source in the ultraviolet to visible light range), so that defects such as bubbles and scratches produce a significant scattering signal. In addition, ultraviolet light is strongly absorbed and weakly reflected by the silicon surface, which can better suppress interference from light reflected from the substrate.

[0032] Furthermore, in order to improve the accuracy of wafer surface defect detection, based on the above embodiment, in other embodiments, such as Figure 1As shown, the first light source module 21 comprises a first bright field irradiation unit 211 and a first dark field irradiation unit 212, the first bright field irradiation unit 211 emits first illumination light to irradiate the wafer surface at a first incident angle, the first dark field irradiation unit 212 emits second illumination light to irradiate the wafer surface at a second incident angle, and the first detection module 22 is configured to acquire a bright field reflection image or a dark field scattering image of the wafer substrate. The second light source module 31 comprises a second dark field irradiation unit 311, which emits third illumination light to irradiate the wafer surface at a third incident angle, and the second detection module 32 is configured to acquire a film layer scattering image of the film layer on the wafer surface.

[0033] The first light source module 21 comprises a first bright field irradiation unit 211 and a first dark field irradiation unit 212. The first bright field irradiation unit 211 is arranged at an angle relative to the wafer surface, so that the optical path of the first illumination light emitted by the first bright field irradiation unit 211 and the axis perpendicular to the wafer surface form a certain angle, and the angle is not 90°, i.e. the first illumination light emitted by the first bright field irradiation unit 211 is obliquely irradiated on the wafer surface at a first incident angle, and the first incident angle is not equal to 0°. The first dark field irradiation unit 212 is arranged at another angle relative to the wafer surface, so that the second illumination light emitted by the first dark field irradiation unit 212 is obliquely irradiated on the wafer surface at a second incident angle, and the second incident angle is not equal to 0°. It should be noted that the first incident angle and the second incident angle are not equal. It should be understood that the first bright field irradiation unit 211 is used for bright field detection of the wafer substrate, and the first dark field irradiation unit 212 is used for dark field detection of the wafer substrate. In order to maximize the contrast of wafer defects and suppress signal noise, the first illumination light is incident at an angle close to the normal (e.g. the angle between the first illumination light and the wafer surface is 70°), and the second illumination light is incident at an angle away from the normal (e.g. the angle between the second illumination light and the wafer surface is 25°). The first detection module 22 is arranged on the optical path of the reflected light of the first illumination light, so that the reflected light signal of the wafer surface to the first illumination light can be received, and the reflected light signal of the second illumination light is avoided, forming a bright field reflection image, and the scattering light signal of the wafer surface irradiated by the second illumination light can also be acquired by the first detection module 22, forming a dark field scattering image.

[0034] The second light source module 31 comprises a second dark field irradiation unit 311. The second dark field irradiation unit 311 is used for dark field imaging of the film layer on the wafer surface. The second dark field irradiation unit 311 is arranged at another angle relative to the wafer surface, so that the third illumination light emitted by the second dark field irradiation unit 311 is obliquely irradiated on the wafer surface at a third incident angle, which is not equal to 0°. It should be noted that the third incident angle and the second incident angle can be equal or not equal, which needs to be set according to the material, thickness and other parameters of the film layer on the wafer surface. It should be understood that the film layer on the wafer surface has high transmittance and poor reflection effect on the light signal, so the bright field detection method has poor defect detection effect on the film layer. Therefore, the embodiment adopts the dark field detection method for the film layer defect, uses the third illumination light emitted by the second irradiation unit to form a scattering light signal on the wafer surface at an angle away from the normal line (for example, the included angle between the third illumination light and the wafer surface is 20°), and forms a film layer scattering image of the wafer surface based on the scattering light signal. It should be noted that the analysis module 4 needs to correct the image distortion caused by the large incident angle before analyzing the film layer scattering image, and then detects the film layer defect.

[0035] Specifically, when scanning the wafer, first, the wafer to be detected is loaded onto the stage 1; second, the first bright field irradiation unit 211 is turned on and emits first illumination light to the wafer surface, and the second dark field irradiation unit 311 is turned on and emits third illumination light to the wafer surface; then, the stage 1 drives the wafer to move from the bright field imaging position to the dark field imaging position, the first detection module 22 acquires the bright field reflection image of the wafer substrate, and the second detection module 32 acquires the film layer scattering image of the wafer film layer; then, the first bright field irradiation unit 211 and the second dark field irradiation unit 311 are turned off, the first dark field irradiation unit 212 is turned on and emits second illumination light to the wafer surface, and the first detection module 22 acquires the dark field scattering image of the wafer substrate; finally, the analysis module 4 analyzes the bright field reflection image and the dark field scattering image to obtain the substrate defect information of the wafer, and analyzes the film layer scattering image to obtain the film layer defect information of the wafer.

[0036] The embodiment realizes multi-channel optical signal separation, multi-camera cooperative imaging by optimizing the optical system, solves the imaging interference of the wafer high-reflective substrate on the low-reflective film layer, synchronously detects the wafer surface defect and the film layer defect, improves the wafer defect detection efficiency, and reduces the equipment cost.

[0037] Further, the first bright field illumination unit 211, the first dark field illumination unit 212 and the second dark field illumination unit 311 in the embodiment can adopt light sources of various colors, such as white light sources, yellow light sources, red light sources, etc., which are not limited in the embodiment. It should be noted that the oblique illumination mode is easy to cause the deformation of the light spot shape, thereby affecting the image uniformity. Therefore, in the embodiment, the first bright field illumination unit 211, the first dark field illumination unit 212 and the second dark field illumination unit 311 all adopt narrow-band line light sources, and the length direction of the narrow-band line light source is orthogonal to the linear movement direction of the wafer, the narrow-band line light source emits a linear light beam, which can reduce the illumination width of the light source, avoid the deformation of the light spot, improve the imaging brightness and the image uniformity, and thus improve the image quality.

[0038] Further, in the above embodiment, as shown in Figure 1 the first bright field illumination unit 211 and the first dark field illumination unit 212 each have a corresponding adjusting device for adjusting at least one of the pitch angle, the horizontal position and the vertical position so that the first incident angle is within the first preset angle range and the second incident angle is within the second preset angle range.

[0039] Specifically, the first bright field illumination unit 211 is arranged on the first adjusting device 213, and the first adjusting device 213 is used to adjust at least one of the pitch angle, the horizontal position and the vertical position so that the first incident angle of the first illumination light is within the first preset angle range. The first dark field illumination unit 212 is arranged on the second adjusting device 214, and the second adjusting device 214 is used to adjust at least one of the pitch angle, the horizontal position and the vertical position so that the second incident angle of the second illumination light is within the second preset angle range.

[0040] It should be noted that the first preset angle range is smaller than the second preset angle range.

[0041] Further, the first detection module 22 includes a first imaging lens 221, a first line array camera 222 and a first camera adjusting device 223. The first imaging lens 221 is used to receive the reflected light of the first illumination light on the base surface of the wafer or the scattered light of the second illumination light on the base surface of the wafer, and transmit the received light beam to the first line array camera 222. The first camera adjusting device 223 is used to adjust at least one of the pitch angle, the horizontal position and the vertical position of the first imaging lens 221, so that the optical axis of the first imaging lens 221 is symmetrical to the optical axis of the first bright field illumination unit 211 about the normal of the surface of the wafer, so as to better acquire the reflected light signal of the first illumination light and the scattered light signal of the second illumination light.

[0042] Further, in the above embodiment, as shown in Figure 1As shown, the second dark-field illumination unit 311 has a corresponding adjusting device for adjusting at least one of the pitch angle, the horizontal position, and the vertical position so that the third incident angle is within a third preset angle range.

[0043] Specifically, the second dark-field illumination unit 311 is disposed on a third adjusting device 312, and the third adjusting device 312 adjusts at least one of the pitch angle, the horizontal position, and the vertical position so that the third incident angle of the third illumination light is within a third preset angle range.

[0044] Further, the second detection module 32 includes a second imaging lens 321, a second linear array camera 322, and a second camera adjusting device 323. The second imaging lens 321 is configured to receive the scattered light of the third illumination light on the film layer of the wafer and transmit the received light beam to the second linear array camera 322. The second camera adjusting device 323 is configured to adjust the pitch angle of the second imaging lens 321 so as to better acquire the scattered light signal of the third illumination light.

[0045] It should be noted that the third preset angle range is greater than the second preset angle range.

[0046] Further, in the embodiment, the first preset angle range is set to [55°, 85°], and the first incident angle is preferably set to 70°. The second preset angle range is set to [10°, 40°], and the second incident angle is preferably set to 25°. The third preset angle range is set to [0°, 40°], and the third incident angle is preferably set to 20°.

[0047] Further, as shown, Figure 1 The carrier 1 includes a carrying part 11 and a driving part 12. The carrying part 11 is disposed on the driving part 12 and is configured to carry and define the wafer. The driving part 12 is configured to drive the carrying part 11 to move linearly so as to drive the wafer to move linearly.

[0048] Specifically, the driving part 12 includes one or more servo driving motors, and the carrying part 11 includes one or more wafer carrying blocks or vacuum chucks. The vacuum chuck is disposed on the output end of the servo driving motor and is configured to adsorb and fix the wafer. The servo driving motor is configured to drive the wafer carrying block or the vacuum chuck to move linearly.

[0049] Further, it should be noted that, in some embodiments, the second detection module 32 can also adjust the imaging angle of the second imaging lens 321 through the second camera adjusting device 323, so as to effectively detect different kinds of film layers.

[0050] Further, in some embodiments, the front side and the back side of the wafer can be covered with film layers, and the front side and the back side of the wafer need to be detected. In order to improve the detection efficiency, on the basis of the above-mentioned embodiments, in other embodiments, as shown in Figure 3 the wafer detection device further comprises a second substrate imaging system 5 and a second film layer imaging system 6, the first substrate imaging system 2 and the first film layer imaging system 3 are arranged on one side of the wafer, and the second substrate imaging system 5 and the second film layer imaging system 6 are arranged on the other side of the wafer. The first light source module 21 and the second light source module 31 are both used to emit illumination light to a first to-be-detected position on the front side of the wafer. The first detection module 22 is used to collect a substrate image at the first to-be-detected position. The second detection module 32 is used to collect a film layer image at the first to-be-detected position. The second substrate imaging system 5 comprises a third light source module 51 and a third detection module 52. The third light source module 51 is used to emit illumination light to a second to-be-detected position on the back side of the wafer. The third detection module 52 is used to collect a substrate image at the second to-be-detected position. The projection positions of the first to-be-detected position and the second to-be-detected position on the front side or the back side of the wafer are mutually staggered. The second film layer imaging system 6 comprises a fourth light source module 61 and a fourth detection module 62. The fourth light source module 61 is used to emit illumination light to the second to-be-detected position. The fourth detection module 62 is used to collect a film layer image at the second to-be-detected position. The analysis module 4 is further electrically connected with the second substrate imaging system 5 and the second film layer imaging system 6 (see Figure 4 ). The analysis module 4 is further used to analyze the substrate images and the film layer images of the first to-be-detected position and the second to-be-detected position, to obtain defect information of the wafer substrate and the film layer.

[0051] It should be noted that in the present embodiment, the working principle of the second substrate imaging system 5 is the same as that of the first substrate imaging system 2, and the working principle of the second film layer imaging system 6 is the same as that of the first film layer imaging system 3. For details, please refer to the above-mentioned embodiments, which will not be described here.

[0052] Specifically, in the present embodiment, by arranging the first substrate imaging system 2 and the first film layer imaging system 3 on the front side of the wafer, and arranging the second substrate imaging system 5 and the second film layer imaging system 6 on the back side of the wafer, the front side and the back side of the wafer can be detected at the same time, thereby improving the detection efficiency. Moreover, when detecting, the first to-be-detected position detected by the first substrate imaging system 2 and the first film layer imaging system 3 and the second to-be-detected position of the second substrate imaging system 5 and the second film layer imaging system 6 are mutually staggered, thereby effectively avoiding the problem of mutual interference of imaging light spots when detecting the front side and the back side of the wafer, thereby improving the detection efficiency while ensuring the detection accuracy.

[0053] Figure 5is a flowchart of a wafer detection method according to an embodiment of the present application. The wafer detection method is applied to the wafer detection device according to one of the above embodiments, and the wafer detection device comprises a stage, a first substrate imaging system, a first film layer imaging system and an analysis module. As shown in Figure 5 the wafer detection method comprises the following steps: S1: loading a wafer to be detected onto the stage; S2: controlling the first light source module and the second light source module to be turned on, the first light source module and the second light source module emitting illumination light to the surface of the wafer, the stage driving the wafer to perform linear motion, the first detection module acquiring a substrate image of the wafer, and the second detection module acquiring a film layer image of the wafer; S3: the analysis module analyzing the substrate image to obtain substrate defect information of the wafer, and analyzing the film layer image to obtain film layer defect information of the wafer.

[0054] It should be noted that the details of steps S1-S3 in this embodiment can be referred to the above-described wafer detection device embodiments, which will not be described here.

[0055] The wafer detection method according to the present application synchronously realizes substrate imaging and film layer imaging of the wafer by using the first substrate imaging system and the first film layer imaging system respectively, thereby realizing synchronous detection of the substrate and the film layer of the wafer, and greatly improving the efficiency of wafer detection.

[0056] Further, the first light source module comprises a first bright field irradiation unit and a first dark field irradiation unit, the second light source module comprises a second dark field irradiation unit, and step S2 specifically comprises: 1. The first bright field irradiation unit is turned on and emits first illumination light to the surface of the wafer, and the second dark field irradiation unit is turned on and emits third illumination light to the surface of the wafer.

[0057] 2. The stage drives the wafer to perform linear motion, the first detection module acquires a bright field reflection image of the substrate of the wafer, and the second detection module acquires a film layer scattering image of the film layer of the wafer.

[0058] 3. The first bright field irradiation unit and the second dark field irradiation unit are turned off, the first dark field irradiation unit is turned on and emits second illumination light to the surface of the wafer.

[0059] 4. The stage drives the wafer to move from the dark field imaging position to the bright field imaging position, and the first detection module acquires a dark field scattering image of the substrate of the wafer.

[0060] Further, the first bright field irradiation unit, the first dark field irradiation unit and the second dark field irradiation unit each have a corresponding adjusting device.

[0061] Therefore, after the step of the first bright field illumination unit being turned on and emitting the first illumination light to the wafer surface, and the second dark field illumination unit being turned on and emitting the third illumination light to the wafer surface, the method further comprises: 1.1, the adjusting device adjusts at least one of the pitch angle, the horizontal position and the vertical position of the first bright field illumination unit, so that the first incident angle of the first illumination light is in a first preset angle range.

[0062] 1.2, the adjusting device adjusts at least one of the pitch angle, the horizontal position and the vertical position of the second dark field illumination unit, so that the third incident angle of the third illumination light is in a third preset angle range.

[0063] After the step of the first dark field illumination unit being turned on and emitting the second illumination light to the wafer surface, the method further comprises: 3.1, the adjusting device adjusts at least one of the pitch angle, the horizontal position and the vertical position of the first dark field illumination unit, so that the second incident angle of the second illumination light is in a second preset angle range.

[0064] It should be noted that in the embodiment, the first preset angle range is smaller than the second preset angle range, and the third preset angle range is larger than the second preset angle range.

[0065] Further, in the step S2, the operation of the first light source module and the second light source module emitting the illumination light to the wafer surface specifically comprises: The first light source module emits the illumination light of the first preset wavelength which is easy to penetrate the film layer to reach the substrate to the wafer surface, and the second light source module emits the illumination light of the second preset wavelength which is easy to reflect or scatter on the surface of the film layer to the wafer surface.

[0066] It should be understood that the detailed contents of the steps in each embodiment of the wafer detection method are referred to the contents of each embodiment of the wafer detection device, which will not be repeated here.

[0067] The above is only the embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation using the contents of the specification and drawings of the present application, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A wafer inspection device, characterized in that: It includes: A carrier, used for carrying a wafer, wherein the wafer has a base and a film layer covering the base; A first substrate imaging system includes a first light source module and a first detection module, wherein the first light source module is used to emit illumination light to the surface of the wafer, and the first detection module is used to collect a substrate image of the wafer; A first film layer imaging system includes a second light source module and a second detection module, wherein the second light source module is used to emit illumination light to the surface of the wafer, and the second detection module is used to collect the film layer image of the wafer; The analysis module is electrically connected to the first substrate imaging system and the first film layer imaging system respectively, and is used to analyze the substrate image to obtain substrate defect information of the wafer, and to analyze the film layer image to obtain film layer defect information of the wafer.

2. The wafer inspection device according to claim 1, wherein: The first light source module includes a first bright field illumination unit and a first dark field illumination unit, wherein the first illumination light emitted by the first bright field illumination unit is illuminated onto the wafer surface at a first incident angle, and the second illumination light emitted by the first dark field illumination unit is illuminated onto the wafer surface at a second incident angle, and the first detection module is used to obtain a bright field reflection image or a dark field scattering image of the wafer substrate; The second light source module includes a second dark field illumination unit, and the third illumination light emitted by the second dark field illumination unit is irradiated to the wafer surface at a third incident angle. The second detection module is used to obtain a film scattering image of the film layer on the wafer surface.

3. The wafer inspection device according to claim 2, wherein: The first bright field illumination unit and the first dark field illumination unit both have corresponding adjustment devices, which are used to adjust at least one of the pitch angle, horizontal position, and vertical position so that the first incident angle is within a first preset angle range and the second incident angle is within a second preset angle range, and the first preset angle range is smaller than the second preset angle range.

4. The wafer inspection device according to claim 3, wherein: The first detection module includes a first imaging lens, a first line array camera and a first camera adjustment device. The first imaging lens is used to receive the reflected light of the first illumination light on the base surface of the wafer or the scattered light of the second illumination light on the base surface of the wafer, and transmit the received light beam to the first line array camera. The first camera adjustment device is used to adjust at least one of the pitch angle, horizontal position and vertical position of the first imaging lens so that the optical axis of the first imaging lens and the optical axis of the first bright field illumination unit are symmetrical about the normal of the surface of the wafer.

5. The wafer inspection device according to claim 3, wherein: The second dark field illumination unit has a corresponding adjustment device for adjusting at least one of the pitch angle, horizontal position, and vertical position so that the third incident angle is within a third preset angle range, and the third preset angle range is greater than the second preset angle range.

6. The wafer inspection device according to claim 5, characterized in that: The second detection module includes a second imaging lens, a second linear array camera and a second camera adjustment device. The second imaging lens is used to receive the scattered light of the third illumination light on the film layer of the wafer and transmit the received light beam to the second linear array camera. The second camera adjustment device is used to adjust the pitch angle of the second imaging lens.

7. The wafer inspection device according to claim 1, wherein: The first light source module is used to emit illumination light of a first preset wavelength that is easy to penetrate the film layer and reach the substrate, and the second light source module is used to emit illumination light of a second preset wavelength that is easy to be reflected or scattered on the surface of the film layer.

8. The wafer inspection device according to claim 1, wherein: The carrier includes a bearing portion and a driving portion, wherein the bearing portion is disposed on the driving portion, the bearing portion is used to bear and limit the wafer, and the driving portion is used to drive the bearing portion to move so as to drive the wafer to move linearly.

9. The wafer inspection device according to claim 1, wherein: It also includes a second substrate imaging system and a second film layer imaging system; The first substrate imaging system and the first film layer imaging system are arranged on one side of the wafer, and the second substrate imaging system and the second film layer imaging system are arranged on the other side of the wafer; The first light source module and the second light source module are both used to emit illumination light to a first position to be measured on the front side of the wafer, the first detection module is used to collect a substrate image at the first position to be measured, and the second detection module is used to collect a film layer image at the first position to be measured; The second substrate imaging system includes a third light source module and a third detection module, wherein the third light source module is used to emit illumination light to a second position to be measured on the back of the wafer, and the third detection module is used to collect a substrate image at the second position to be measured, and the projection positions of the first position to be measured and the second position to be measured on the front or back of the wafer are staggered. The second film layer imaging system includes a fourth light source module and a fourth detection module, wherein the fourth light source module is used to emit illumination light to the second position to be measured, and the fourth detection module is used to collect the film layer image at the second position to be measured; The analysis module is also electrically connected to the second substrate imaging system and the second film layer imaging system respectively. The analysis module is also used to analyze the substrate image and film layer image of the first and second test positions to obtain defect information of the wafer substrate and film layer.

10. A wafer detection method, characterized in that: It is applied to the wafer detection device according to any one of claims 1 to 8; the method comprises: Loading the wafer to be inspected onto the stage; Controlling the first light source module and the second light source module to be turned on, so that the first light source module and the second light source module emit illumination light to the surface of the wafer, the stage drives the wafer to perform linear motion, the first detection module acquires a base image of the wafer, and the second detection module acquires a film layer image of the wafer; The analysis module analyzes the substrate image to obtain substrate defect information of the wafer, and analyzes the film layer image to obtain film layer defect information of the wafer.

11. The wafer detection method according to claim 10, characterized in that: The first light source module includes a first bright field illumination unit and a first dark field illumination unit, and the second light source module includes a second dark field illumination unit; Controlling the first light source module and the second light source module to turn on, the first light source module and the second light source module to emit illumination light to the surface of the wafer, the stage driving the wafer to perform linear motion, the first detection module acquiring a base image of the wafer, and the second detection module acquiring a film layer image of the wafer, including: The first bright field illumination unit is turned on and emits a first illumination light to the wafer surface, and the second dark field illumination unit is turned on and emits a third illumination light to the wafer surface; The carrier drives the wafer to move linearly, the first detection module obtains a bright field reflection image of the wafer substrate, and the second detection module obtains a film layer scattering image of the wafer film layer; The first bright field illumination unit and the second dark field illumination unit are turned off, and the first dark field illumination unit is turned on and emits a second illumination light to the wafer surface; The stage drives the wafer to move from a dark field imaging position to a bright field imaging position, and the first detection module acquires a dark field scattering image of the wafer substrate.

12. The wafer detection method according to claim 11, characterized in that: The first bright field illumination unit, the first dark field illumination unit, and the second dark field illumination unit all have corresponding adjustment devices; After the first bright field illumination unit is turned on and emits the first illumination light to the wafer surface, and the second dark field illumination unit is turned on and emits the third illumination light to the wafer surface, the method further includes: the adjustment device adjusts at least one of the pitch angle, horizontal position, and vertical position of the first bright field illumination unit so that the first incident angle of the first illumination light is within a first preset angle range; the adjustment device adjusts at least one of the pitch angle, horizontal position, and vertical position of the second dark field illumination unit so that the third incident angle of the third illumination light is within a third preset angle range; After the first dark field illumination unit is turned on and emits the second illumination light to the wafer surface, the method further includes: the adjustment device adjusts at least one of the pitch angle, horizontal position, and vertical position of the first dark field illumination unit so that the second incident angle of the second illumination light is within a second preset angle range; The first preset angle range is smaller than the second preset angle range, and the third preset angle range is larger than the second preset angle range.

13. The wafer detection method according to claim 10, wherein: The first light source module and the second light source module emit illumination light to the wafer surface, including: The first light source module emits illumination light of a first preset wavelength that can easily penetrate the film layer and reach the substrate to the wafer surface, and the second light source module emits illumination light of a second preset wavelength that can easily be reflected or scattered on the film layer surface to the wafer surface.

Images