CN-122016811-A - Wafer bonding light source control method, wafer bonding device and computer readable storage medium

CN122016811ACN 122016811 ACN122016811 ACN 122016811ACN-122016811-A

Abstract

The application discloses a wafer bonding light source control method, a wafer bonding device and a computer readable storage medium, which relate to the technical field of wafer manufacturing, and are used for comparing a target spectrum value with a current spectrum value to obtain a spectrum difference value and obtain a spectrum threshold value. The arrangement can adjust the optical filter, so that the center band drifting problem is effectively restrained, and the illumination light spectrum irradiated to the wafer to be measured is ensured to be stable all the time and highly adapted to the process requirement. The method can ensure that the quality of the acquired mark image reaches the standard, provides a reliable basis for accurate identification and positioning of a vision system, improves the consistency of wafer detection of the same batch, and further effectively improves the process precision and alignment accuracy of wafer bonding.

Inventors

YE TONGDI
CHEN SHUBIN
JIANG RUIQIAN
ZHENG TAO
WU XIAOHONG
WU ZEGUANG
WANG YIHAO

Assignees

东莞触点智能装备有限公司

Dates

Publication Date: 20260512
Application Date: 20260212

Claims (12)

1. The wafer bonding light source control method is characterized by comprising the following steps of: acquiring a current optical parameter and a target optical parameter of a wafer to be detected, wherein the current optical parameter comprises a current spectrum value of the wafer to be detected, the target optical parameter comprises a target spectrum value of the wafer to be detected, and comparing the target spectrum value with the current spectrum value to obtain a spectrum difference value; Obtaining a spectrum threshold value, and controlling a driving piece to drive a filter rotating wheel to adjust the current spectrum value by switching a region of the filter rotating wheel, in which the filter filters illumination light, under the condition that the spectrum difference value is larger than the spectrum threshold value, and enabling the spectrum difference value to be smaller than or equal to the spectrum threshold value; and controlling a camera to acquire the image information of the wafer to be detected under the condition that the spectrum difference value is smaller than or equal to the spectrum threshold value.
2. The method for controlling a light source for wafer bonding according to claim 1, further comprising, before obtaining the current optical parameter and the target optical parameter of the wafer to be tested: And acquiring filter information of the wafer to be tested, and controlling the driving piece to drive the filter rotating wheel according to the filter information so that the corresponding filter is switched to the light path of the illumination light to form corresponding wave band light to irradiate the wafer to be tested.
3. The method for controlling a light source bonded to a wafer according to claim 2, wherein obtaining the filter information of the wafer to be tested comprises: And acquiring material information of the wafer to be tested, and determining filter information of the wafer to be tested through the material information of the wafer to be tested.
4. The method for controlling a light source for wafer bonding according to claim 1, further comprising, before controlling the camera to collect the image information of the wafer to be tested: Acquiring current optical parameters and target optical parameters of the wafer to be tested, wherein the target optical parameters further comprise target light intensity, the current optical parameters comprise current light intensity, and the current light intensity and the target light intensity are compared to obtain a light intensity difference value; And obtaining a light intensity threshold value, and adjusting a light intensity adjusting unit of the wafer bonding device according to the light intensity difference value and the light intensity threshold value so that the light intensity difference value is smaller than or equal to the light intensity threshold value.
5. The method for controlling a light source for wafer bonding according to any one of claims 1 to 4, wherein the obtaining the target optical parameter of the wafer to be tested comprises: Controlling the driving piece to drive the optical filter rotating wheel so that a plurality of optical filters on the optical filter rotating wheel sequentially filter the illumination light to form a plurality of wave band lights with different wave bands and irradiate a sample wafer; Under the condition that each wave band irradiates the sample wafer, controlling the camera to acquire an image of the sample wafer, and obtaining the current optical parameter corresponding to each piece of image information through a spectrum detection piece; Comparing the contrast of the images, determining the image with the highest contrast, determining the current optical parameter corresponding to the image as the target optical parameter corresponding to the wafer to be tested, and determining the corresponding optical filter information as the optical filter information corresponding to the wafer to be tested.
6. The method of claim 1, wherein the target spectral values include a center wavelength and a bandwidth of light impinging on the wafer; And/or the spectral threshold comprises a central wavelength threshold of 0.2nm and a bandwidth threshold of 0.3nm.
7. The wafer bonding device is characterized by comprising a full-band light source, a light filter rotating wheel, a driving piece, a spectrum detection piece and a camera, wherein the light filter is arranged on the light filter rotating wheel, the full-band light source emits illumination light to the light filter, the light filter is used for receiving and filtering the illumination light to form band light, the band light is used for illuminating a wafer, the camera is used for collecting image information of the wafer, the driving piece is in transmission connection with the light filter rotating wheel, and the spectrum detection piece is used for detecting current optical parameters of a region of the wafer irradiated by the band light; the wafer bonding device further comprises an acquisition module, an adjustment module and an image module, wherein: The acquisition module is used for acquiring current optical parameters and target optical parameters of a wafer to be detected, wherein the current optical parameters comprise current spectrum values, the target optical parameters comprise target spectrum values of the wafer to be detected, and the target spectrum values and the current spectrum values are compared to obtain spectrum difference values; the adjusting module is used for obtaining a spectrum threshold value, and controlling the driving piece to drive the optical filter rotating wheel to adjust the current spectrum value by switching the optical filter on the optical filter rotating wheel to filter the area of the illumination light under the condition that the spectrum difference value is larger than the spectrum threshold value, and enabling the spectrum difference value to be smaller than or equal to the spectrum threshold value; The image module is used for controlling the camera to acquire the image information of the wafer to be detected under the condition that the spectrum difference value is smaller than or equal to the spectrum threshold value.
8. The wafer bonding apparatus according to claim 7, further comprising a reflective sheet for reflecting the band light to the beam splitter sheet, and a beam splitter sheet for reflecting the band light to the wafer to form image light, the image light being transmitted through the beam splitter sheet and conducted to the camera.
9. The wafer bonding apparatus according to claim 7, wherein the full-band light source is a laser driving light source, and the range of the illumination light band emitted by the full-band light source is 190nm-1700nm; And/or the number of the optical filters is multiple, the optical filters are respectively used for filtering light of different wave bands, the wafer bonding device further comprises an optical filter rotating wheel, and the optical filters are arranged at intervals along the circumferential direction of the optical filter rotating wheel.
10. The wafer bonding apparatus according to claim 7, further comprising a light intensity adjusting unit for adjusting the light intensity of the illumination light and emitting the illumination light, and/or a spot shaping and homogenizing unit for collimating and homogenizing the illumination light.
11. The wafer bonding apparatus according to claim 10, wherein the spot shaping and homogenizing unit includes a microlens array and a field lens, the microlens array being disposed on an outgoing light path of the full-band light source, the microlens array receiving the illumination light and outgoing it to the field lens, the field lens receiving and outgoing the illumination light; And/or the light intensity adjusting unit comprises an iris diaphragm, and the iris diaphragm is used for receiving the illumination light, adjusting the light intensity of the illumination light and emitting the illumination light to the optical filter.
12. A computer-readable storage medium, wherein a program is stored in the medium, the program being capable of being loaded by a processor and executing the wafer-bonded light source control method according to any one of claims 1 to 6.

Description

Wafer bonding light source control method, wafer bonding device and computer readable storage medium Technical Field The present application relates to the field of wafer manufacturing technologies, and in particular, to a wafer bonding light source control method, a wafer bonding device, and a computer readable storage medium. Background Wafer-to-Wafer bonding is also known as Wafer direct bonding and generally refers to the process of bonding two wafers together. In the field of semiconductor technology, wafer-to-wafer three-dimensional integration can be realized by adopting a wafer direct bonding technology, namely bonding two or more wafers with the same or different functions. With the development of the era, the requirement on the bonding alignment precision between two wafers is also higher and higher. However, in the actual use process, the wafer bonding process is affected by the accuracy of the image acquired by the camera, mark (alignment mark) images acquired by the camera in the wafer bonding process are unclear, so that a visual algorithm can identify the positioning deviation and even failure of the bonding process, core defects such as wafer alignment error and bonding failure are caused, and serious consequences of yield drop, wafer scrapping and production line process interruption are caused. Disclosure of Invention The present application is directed to a wafer bonding light source control method, a wafer bonding device and a computer readable storage medium, which alleviate or solve the above-mentioned technical problems in the prior art. In a first aspect, an embodiment of the present application discloses a method for controlling a light source for wafer bonding, where the method includes obtaining a current optical parameter and a target optical parameter of a wafer to be tested, where the current optical parameter includes a current spectral value of the wafer to be tested, and the target optical parameter includes a target spectral value of the wafer to be tested, comparing the target spectral value with the current spectral value to obtain a spectral difference value, obtaining a spectral threshold, and controlling a driving element to drive a filter wheel when the spectral difference value is greater than the spectral threshold, so as to adjust the current spectral value by switching an area of a filter filtering illumination light on the filter wheel, and make the spectral difference value less than or equal to the spectral threshold, and controlling a camera to collect image information of the wafer to be tested when the spectral difference value is less than or equal to the spectral threshold. In a second aspect, an embodiment of the present application discloses a wafer bonding device, the wafer bonding device includes a full-band light source, a filter wheel, a driving member, a spectrum detecting member and a camera, the full-band light source emits illumination light to the filter, the filter wheel is provided with the filter, the filter is used for receiving and filtering the illumination light to form band light, the band light is used for illuminating a wafer, the camera is used for collecting image information of the wafer, the driving member is in transmission connection with the filter, the spectrum detecting member is used for detecting a current optical parameter of a region of the wafer illuminated by the band light, the wafer bonding device further includes an obtaining module, an adjusting module and an image module, the obtaining module is used for obtaining the current optical parameter and a target optical parameter of the wafer to be tested, the target optical parameter includes a target spectral value of the wafer to be tested, the target spectral value is compared with the current spectral value to obtain a spectral difference value, the adjusting module is used for obtaining a spectral threshold, under the condition that the spectral difference is greater than the spectral threshold, the driving member is controlled to drive the filter wheel to adjust the current value by switching the region of the filter on the filter wheel to filter illumination light, and the difference is made to be smaller than or equal to the threshold, the image is used for controlling the spectral information to be smaller than the image to be detected by the camera under the condition that the spectral information is smaller than the threshold. In a third aspect, an embodiment of the present application discloses a computer-readable storage medium in which a program is stored, the program being capable of being loaded by a processor and performing a method of controlling a light source as in the wafer bonding of the first aspect. The technical scheme adopted by the application can achieve the following beneficial effects: The full-band light source can emit illumination light, further, the full-band light source can be a Laser Driving Light Source (LDLS) and the like, and the e