White light interferometer for measuring residual glue on bottom surface of transparent dielectric layer

Abstract

The utility model discloses a white light interferometer for measuring residual glue on the bottom surface of a transparent dielectric layer, which comprises a laser light source, a white light source, a convex lens I, a reference mirror, an optical filter, an optical signal detector, a lens, an objective lens, a sample table, a spectroscope I, a spectroscope II, a CCD (Charge Coupled Device) image sensor, a convex lens II and a computer, the first convex lens and the second convex lens are located at the transmitting ends of the laser light source and the white light source respectively. According to the utility model, the optical signal detector is additionally arranged in the optical path system, the optical signal detector can measure the intensity of received light, when the intensity of the light of the optical signal detector reaches the maximum value, the light emitted by the white light interferometer is focused on the surface of the residual glue at the bottom layer of the transparent medium, and observation is carried out according to the position information at the moment, so that the detection accuracy is improved. Alignment to the area of the bottom surface of the transparent medium layer can be imaged, the function of analyzing the residual glue on the bottom surface of the transparent medium layer is achieved, and the residual glue on the bottom surface of the transparent medium layer can be measured.

Description

Technical Field

[0001] The utility model relates to the technical field of superconducting quantum computing, in particular to a white light interferometer for measuring residual glue on the bottom surface of a transparent dielectric layer. Background Technique

[0002] With the rise of artificial intelligence, the demand for high computing power of computers has become increasingly prominent. Compared with traditional computers, the superiority of the computing power of superconducting quantum computers has been proven. Developing superconducting quantum computers with higher performance is an extremely urgent task at present. The expansion of the scale of quantum bits is an important factor restricting the improvement of superconducting quantum computing power. However, as the scale of superconducting quantum bit chips gradually increases, the back-end failure analysis of the chips becomes increasingly important. From the processing aspect, one of the main factors causing the failure of superconducting quantum computing chips is the residual thin photoresist. However, for the fabricated chips, the residual photoresist is often covered by a transparent dielectric layer and is extremely thin, with a general thickness of about 1 nm. At this time, it is impossible to successfully detect and characterize the residual glue using an optical microscope, an electron microscope, or even an EDS analyzer.

[0003] A white light interferometer uses the principle of light interference to measure the surface topography of a sample. The working principle is as follows: It is equipped with a group of white light sources. The white light emitted by the light source is split into two beams by a beam splitter: one beam irradiates on the surface of the sample, and the other beam irradiates on a reference mirror. When these two beams return, an optical path difference will be formed due to the reflection of the sample surface and the reference mirror. When the optical path difference of these two beams meets certain conditions, they will converge at a certain point in space and interfere, forming bright and dark interference fringes. The brightness or movement of these interference fringes is related to the topographic features of the sample surface. By measuring the changes in these interference fringes, the three-dimensional topography or other relevant physical quantities of the sample surface can be obtained. A white light interferometer is an instrument with extremely high precision in the height direction. Common white light interferometers on the market can generally reach an accuracy of 0.1 - 0.01 nm, which is an effective method for detecting extremely thin photoresist. However, current white light interferometers generally only respond to the undulations on the surface of the thin film. When performing the failure analysis of chips, it is difficult to directly analyze the residual glue at the bottom of the transparent dielectric. Content of the Utility Model

[0004] The purpose of the utility model is to provide a white light interferometer for measuring residual glue on the bottom surface of a transparent dielectric layer, so as to solve the problems raised in the above background technique.

[0005] To achieve the above purpose, the utility model provides the following technical solutions:

[0006] A white light interferometer for measuring residual glue on the bottom surface of a transparent medium layer, comprising: a laser light source, a white light source, a first convex lens, a reference mirror, a filter, an optical signal detector, a lens, an objective lens, a sample stage, a first beam splitter, a second beam splitter, a CCD image sensor, a second convex lens, and a computer. The first convex lens and the second convex lens are respectively located at the emission ends of the laser light source and the white light source, and a second beam splitter, a filter, a first beam splitter, an objective lens, and a sample stage are respectively arranged on the other sides of the first convex lens and the second convex lens. A lens is arranged on the other side of the first beam splitter, and an optical signal detector is arranged on the other side of the lens. A reference mirror and a CCD image sensor are respectively arranged on the other two sides of the second beam splitter.

[0007] As a further solution of the utility model: a sample to be measured is placed on the surface of the sample stage, and a Z-direction control device is installed on the sample stage.

[0008] As a still further solution of the utility model: the CCD image sensor is electrically connected to the computer.

[0009] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0010] The utility model adds a laser as an auxiliary light source in the traditional white light interferometer to work together with the white light source, and adds an optical signal detector in the optical path system. The optical signal detector can measure the intensity of the received light. When the intensity of the light of the optical signal detector reaches the maximum value, it indicates that the light emitted from the white light interferometer has been focused on the surface of the residual glue at the bottom layer of the transparent medium. By observing according to the position information at this time, imaging of the area aligned with the bottom surface of the transparent medium layer can be achieved, so as to analyze the residual glue on the bottom surface of the transparent layer, which helps to measure the residual glue at the bottom layer of the transparent medium. Description of the Drawings

[0011] Figure 1 It is a schematic structural diagram of a white light interferometer for measuring residual glue on the bottom surface of a transparent medium layer.

[0012] In the figure: 1 - laser light source, 2 - white light source, 3 - first convex lens, 4 - reference mirror, 5 - filter, 6 - optical signal detector, 7 - lens, 8 - objective lens, 9 - sample to be measured, 10 - sample stage, 11 - Z-direction control device, 12 - first beam splitter, 13 - second beam splitter, 14 - CCD image sensor, 15 - second convex lens, 16 - computer. Detailed Embodiment

[0013] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0014] Embodiment 1

[0015] Please refer to Figure 1 , a white light interferometer for measuring residual glue on the bottom surface of a transparent dielectric layer, comprising: a laser light source 1, a white light source 2, a first convex lens 3, a reference mirror 4, a filter 5, an optical signal detector 6, a lens 7, an objective lens 8, a sample stage 10, a first beam splitter 12, a second beam splitter 13, a CCD image sensor 14, a second convex lens 15 and a computer 16. The first convex lens 3 and the second convex lens 15 are respectively located at the emission ends of the laser light source 1 and the white light source 2, and on the other sides of the first convex lens 3 and the second convex lens 15, there are respectively arranged a second beam splitter 13, a filter 5, a first beam splitter 12, an objective lens 8 and a sample stage 10. On the other side of the first beam splitter 12, there is a lens 7, and on the other side of the lens 7, there is an optical signal detector 6. On the other two sides of the second beam splitter 13, there are respectively arranged a reference mirror 4 and a CCD image sensor 14.

[0016] Preferably, a sample to be measured 9 is placed on the surface of the sample stage 10, and a Z-direction control device 11 is installed on the sample stage 10.

[0017] Preferably, the CCD image sensor 14 is electrically connected to the computer 16.

[0018] Specifically: The laser light source 1 can emit laser light of a fixed wavelength; the white light source 2 can emit white light; the first convex lens 3 can convert the light from the white light source 2 into parallel light; the parallel light reaches the reference mirror 4 after being reflected by the second beam splitter 13, and reaches the CCD image sensor 14 after being reflected by the reference mirror 4; the filter 5 can filter out light with the same wavelength as the laser; the optical signal detector 6 can measure the intensity of the light reflected from the first beam splitter 12; the lens 7 at the front end of the optical signal detector 6 can focus the parallel light into the optical signal detector 6; the objective lens 8 can focus the light from the dual light sources on the surface of the sample to be measured 9; the Z-direction control device 11 can move the sample stage 10 in the Z direction; the first beam splitter 12 can achieve the transmission and reflection of incident light. The light from the dual light sources passes through the first beam splitter 12 and irradiates the surface of the sample to be measured 9, and after reflection, it can enter the optical signal detector 6 through the first beam splitter 12; the light from the dual light sources can pass through the second beam splitter 13 and irradiate the surface of the sample to be measured 9. At the same time, the white light emitted by the white light source 1 can also reach the reference mirror 4 after being reflected by the second beam splitter 13. In addition, the light reflected from the surface of the sample to be measured 9 enters the CCD image sensor 14 after being reflected by the second beam splitter 13; the CCD image sensor 14 can convert the optical image into an electrical signal to form an image of the sample. The light reflected from the reference mirror 4 and the light reflected from the surface of the sample 9 will form interference, which is then collected by the CCD image sensor 14 and converted into an electrical signal; the second convex lens 15 can convert the light from the laser light source 2 into parallel light; the computer 16 can analyze the electrical signal of the CCD image sensor 14 to form the surface topography of the sample.

[0019] Working principle: Turn on the white light source 2, remove the filter 5 and the first beam splitter 12. The light is irradiated onto the surface of the sample to be measured 9 through the objective lens 8 and then reflected. The reflected optical signal is collected and imaged by the CCD image sensor 14 through the second beam splitter 13. Move the sample stage 10 (in the XY direction) to find the area to be observed; turn on the laser light source 1, insert the filter 5 and the first beam splitter 12. The light emitted by the laser light source 1 and the white light source 2 will irradiate the surface of the sample to be measured 9 through the second beam splitter 13, the filter 5, the first beam splitter 12 and the objective lens 8. The light reflected from the surface of the sample to be measured 9 will be reflected by the first beam splitter 12 and reach the optical signal detector 6; adjust the Z-direction control device 11 to change the distance of the sample stage 10 in the Z direction, and at the same time pay attention to observing the value of the optical signal detector 6. When the value of the optical signal detector 6 reaches the maximum, stop adjusting the Z-direction control device 11. At this time, the light has been focused on the surface of the residual glue at the bottom layer of the transparent medium; turn off the laser light source 1, remove the filter 5 and the first beam splitter 12, and perform the test with the white light source 2; read the signal of the CCD image sensor 14 from the computer 16, and convert the signal into an image signal to obtain the image information of the residual glue at the bottom surface of the transparent layer, so as to measure the residual glue at the bottom layer of the transparent medium.

[0020] It should be particularly noted that: In this utility model, a laser is added as an auxiliary light source in a traditional white light interferometer to work together with the white light source 2, and an optical signal detector 6 is added in the optical path system. The optical signal detector 6 can measure the intensity of the received light. When the intensity of the light of the optical signal detector 6 reaches the maximum value, it indicates that the light emitted from the white light interferometer has been focused on the surface of the residual glue at the bottom layer of the transparent medium. By observing according to the position information at this time, imaging of the area aligned with the bottom surface of the transparent medium layer can be achieved, serving the purpose of analyzing the residual glue on the bottom surface of the transparent layer, and helping to realize the measurement of the residual glue at the bottom layer of the transparent medium.

[0021] For those skilled in the art, it is obvious that this utility model is not limited to the details of the above-mentioned exemplary embodiments, and without departing from the spirit or basic characteristics of this utility model, this utility model can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of this utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within this utility model.

[0022] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A white light interferometer for measuring adhesive residue on the bottom surface of a transparent medium layer, comprising: A laser light source (1), a white light source (2), a convex lens 1 (3), a reference mirror (4), a filter (5), an optical signal detector (6), a lens (7), an objective lens (8), a sample stage (10), a beam splitter 1 (12), a beam splitter 2 (13), a CCD image sensor (14), a convex lens 2 (15) and a computer (16), wherein the convex lens 1 (3) and the convex lens 2 (15) are respectively located at the emitting ends of the laser light source (1) and the white light source (2), and the convex lens 1 (3) and the convex lens 2 (15) are respectively located at the emitting ends of the laser light source (1) and the white light source (2), and the convex lens 1 (3) and the convex lens 2 (15 ) are respectively provided on the other side with a second spectroscope (13), a filter (5), a first spectroscope (12), an objective lens (8) and a sample stage (10); a lens (7) is provided on the other side of the first spectroscope (12); a light signal detector (6) is provided on the other side of the lens (7); a reference mirror (4) and a CCD image sensor (14) are respectively provided on the other two sides of the second spectroscope (13); a sample to be tested (9) is placed on the surface of the sample stage (10), and a Z-direction control device (11) is installed on the sample stage (10).

2. The white light interferometer for measuring adhesive residue on the bottom surface of a transparent medium layer according to claim 1, characterized in that: The CCD image sensor (14) is electrically connected to a computer (16).

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