Diamond internal micro-channel processing system based on femtosecond laser space shaping

Abstract

The invention provides a femtosecond laser space shaping-based diamond internal micro-channel processing system, which is used for pretreating a diamond, adding a protective layer on the surface of the diamond, processing a microgroove in the surface of the diamond by using a femtosecond laser space shaping light path, removing the protective layer and cleaning the diamond again. And finally, the diamond and the fused quartz are welded through a femtosecond laser space shaping light path. That is to say, the femtosecond laser space shaping technology and reasonable path planning are utilized, the surface rectangular microgrooves with the large depth-to-width ratio under the small-size condition and various microgroove structures in the complex trend can be obtained on the diamond surface, and on the basis of absorption of the protective layer, the microgrooves in the diamond surface can be obtained. The method has the advantages that the laser focusing is utilized, the phenomenon that the width of an inlet of a microgroove in the surface of the diamond is increased due to laser zooming is inhibited, heterogeneous material welding of the diamond and the fused quartz is achieved through the femtosecond laser space shaping technology, machining of a micro-channel in the diamond is achieved, and a guarantee is provided for heat dissipation of a high-frequency and high-power electronic chip.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of femtosecond laser micro-nano manufacturing technology, and particularly relates to a processing system for internal micro-channels of diamond based on spatial shaping of femtosecond laser. BACKGROUND

[0002] With the continuous improvement of the miniaturization and integration of power devices, the power density and heat production efficiency of new electronic chips have significantly increased. Studies have shown that up to 55% of electronic chip failures are directly attributed to excessively high operating temperatures. More seriously, when the chip temperature exceeds the critical point of 75℃, the reliability will decrease by 5% for every 1℃ increase in temperature. Therefore, developing more efficient and reliable heat dissipation solutions has become an urgent need to improve the performance and lifespan of chips.

[0003] Current mainstream chip heat dissipation technologies, such as air cooling and heat spreader cooling, have inherent defects such as limited heat dissipation efficiency, slow thermal response speed, and large space occupation, which have made it difficult to meet the increasingly stringent heat dissipation requirements of modern high-frequency and high-power chips. In contrast, liquid cooling technology has become the preferred solution for high-power density electronic chip heat dissipation due to its excellent heat dissipation efficiency, precise temperature control capability, and good spatial adaptability. The performance of a liquid cooling radiator depends on two key factors: the thermal conductivity of the heat dissipation substrate material and the design and processing precision of the radiator micro-channel structure.

[0004] In terms of heat dissipation materials, diamond, as the representative of the fourth generation of semiconductor materials, exhibits unparalleled advantages: its extremely high thermal conductivity (single crystal diamond can reach 2400 W / m·K) is significantly better than other semiconductor materials; at the same time, its extremely low thermal expansion coefficient (about 0.8 ppm / K) and excellent physical and chemical stability can effectively reduce thermal stress and significantly improve the overall reliability and service life of chips and radiators. In terms of micro-channel structure, its shape, direction, and size have a decisive influence on the heat dissipation performance. The structure of the flow channel directly affects the effective contact area between the heat dissipation fluid and the solid wall and the fluid dynamics characteristics (such as flow state and turbulence intensity), thereby affecting the heat exchange efficiency. Heat transfer theory indicates that under the condition of keeping the Nusselt number constant, reducing the characteristic size of the micro-channel helps to obtain a higher convective heat transfer coefficient. However, the reduction of micro-channel size will significantly increase the flow resistance of the fluid, leading to a decrease in flow rate, which may weaken the overall heat exchange efficiency. Therefore, optimizing the micro-channel structure must seek the best balance point between maximizing the convective heat transfer coefficient and minimizing the flow resistance to maintain sufficient flow rate.

[0005] However, the application of diamond materials in high-efficiency micro-channel liquid cooling radiators faces two key and interrelated technical bottlenecks in the manufacturing process: Bottleneck one: difficulty in high-precision micro-machining of diamond surface - As one of the hardest materials known, it is extremely difficult to precisely machine the microstructure on the surface of diamond. Traditional mechanical machining methods are inefficient (the present invention uses laser machining, while existing methods use mechanical machining), have limited precision and are prone to introduce damage, while conventional laser machining may cause material graphitization or micro-cracks due to thermal effects, making it difficult to efficiently and accurately prepare complex micro-channel structures on the surface of diamond as required by design.

[0006] Bottleneck two: difficulty in high-efficiency forming of three-dimensional micro-channels inside diamond - The current mainstream methods for constructing closed micro-channels inside diamond (such as CVD diamond regrowth and diamond cumulative bonding) have fundamental limitations: extremely low processing efficiency, high cost, and inability to accurately control the three-dimensional morphology of the internal micro-channels (morphology is not faithful). These methods often fail to achieve complex, high-aspect-ratio, or specific three-dimensional micro-channels, resulting in significant deviations between the actual formed channel structure and the thermal design target, severely restricting the optimization potential of heat dissipation performance.

[0007] Therefore, there is an urgent need to develop a new manufacturing technology that can overcome the above bottlenecks and efficiently and accurately machine complex three-dimensional micro-channel structures with good shape retention inside diamond to meet the extreme heat dissipation performance requirements of the next generation of high-power chips. SUMMARY

[0008] To solve the above problems, the present invention provides a processing system for micro-channels inside diamond based on femtosecond laser spatial shaping, which can efficiently and accurately machine complex three-dimensional micro-channel structures with good shape retention inside diamond to meet the extreme heat dissipation performance requirements of the next generation of high-power chips.

[0009] A processing system for micro-channels inside diamond based on femtosecond laser spatial shaping, comprising a protective layer processing module, a micro-channel processing module, a cleaning module, and a welding module; The protective layer processing module is used to add a polyimide protective layer on the surface of the diamond to be processed; The micro-channel processing module is used to process a micro-channel with a set pattern on the surface of the diamond to be processed with a polyimide protective layer according to a set processing path; wherein the polyimide protective layer is used to absorb part of the energy of the femtosecond laser that contacts the entrance of the micro-channel when the femtosecond laser spot moves downward along the longitudinal direction of the diamond to ablate the micro-channel, so that the remaining energy of the femtosecond laser that contacts the entrance of the micro-channel is lower than the ablation energy corresponding to the ablation threshold of the diamond; The cleaning module is used to clean the remaining polyimide protective layer on the diamond with the micro-channel, obtaining a diamond micro-channel embryo; The welding module is used for welding the fused quartz on the micro-channel surface of the diamond micro-channel embryo to complete the packaging of the micro-channel.

[0010] Further, the greater the thickness of the polyimide protective layer, the more energy of the femtosecond laser absorbed, and the smaller the increment of the micro-channel entrance width ablated by the femtosecond laser.

[0011] Further, the thickness of the polyimide protective layer on each region of the surface to be machined of the diamond is the same, so that when the femtosecond laser energy during the machining process is constant, the entrance width of the micro-channel ablated by the femtosecond laser is the same.

[0012] Further, the thickness of the polyimide protective layer on each region of the surface to be machined of the diamond is the same, so that when the femtosecond laser energy during the machining process is changed, the increment of the entrance width of the micro-channel ablated by the femtosecond laser is not completely the same, wherein the greater the femtosecond laser energy, the greater the increment of the entrance width of the micro-channel, and the smaller the femtosecond laser energy, the smaller the increment of the entrance width of the micro-channel.

[0013] Further, the protective layer machining module first uses alcohol and deionized water solution to clean the diamond for 5 minutes before adding the polyimide protective layer on the surface to be machined of the diamond.

[0014] Further, the method for the cleaning module to clean the residual polyimide protective layer on the diamond with the micro-channel is: First, use alcohol to clean the diamond with the micro-channel for 30 minutes, and then use deionized water to clean the diamond after alcohol cleaning for 5 minutes.

[0015] Further, the micro-channel machining module includes a femtosecond laser (1), a mirror one (2), a mirror two (3), a half-wave plate (4), a polarization beam splitter (5), a mirror three (6), an optical diffraction element (7), a quarter-wave plate (8), a mirror four (9), a mirror five (10), a dichroic mirror (11), a focusing objective (12), a three-dimensional displacement table (14), a beam splitter (15), a white light source (16), and an imaging CCD (17), and the method for the micro-channel machining module to machine the micro-channel with the set pattern on the surface to be machined of the diamond with the polyimide protective layer by the femtosecond laser according to the set machining path is: The femtosecond laser (1) generates femtosecond laser pulses, which pass through the mirror one (2), the mirror two (3), the half-wave plate (4), the polarization beam splitter (5), the mirror three (6), the optical diffraction element (7), the quarter-wave plate (8), the mirror four (9), the mirror five (10), are reflected by the dichroic mirror (11) after being focused by the focusing objective (12), and then are focused on the diamond (13) surface to be processed with a polyimide protective layer. The diamond (13) is fixed on the three-dimensional displacement table (14); the white light source (16) passes through the beam splitter (15) and the dichroic mirror (11), is reflected by the beam splitter (15) and is incident into the imaging CCD (17). According to the set processing path, the three-dimensional displacement table (14) is translated and moved up and down, so that the femtosecond laser spot is focused at different positions inside the diamond for ablation until a microchannel with a set pattern is obtained.

[0016] Further, before ablation of the diamond by the femtosecond laser spot, the energy distribution of the femtosecond laser spot is first adjusted, and the adjustment method is as follows: The fluorescent card is placed on the three-dimensional displacement table, the position of the optical diffraction element (7) in the optical path is adjusted until the diffraction ring generated by the femtosecond laser on the fluorescent card covers the entire femtosecond laser spot; The beam quality analyzer is placed on the three-dimensional displacement table, the femtosecond laser spot is vertically incident on the beam quality analyzer, and then the position of the optical diffraction element (7) in the optical path is adjusted through the spot energy distribution on the computer connected to the beam quality analyzer until the uniformity of the femtosecond laser spot energy meets the requirements.

[0017] Further, the required microchannel of the diamond includes a surface straight microchannel and a patterned microchannel combined with curves and straight lines; wherein the processing path of the surface straight microchannel is first transverse and then longitudinal; the processing path of the patterned microchannel is to realize closed loop scanning on the surface of the diamond according to the contour of the pattern in a specific direction.

[0018] Advantages: 1. The application provides a kind of machining system of diamond internal microchannel based on femtosecond laser space shaping, diamond is pretreated, protective layer is added on the surface of diamond, microgroove is machined on the surface of diamond using femtosecond laser space shaping optical path, protective layer is removed, diamond is cleaned again, finally, diamond and fused quartz are welded using femtosecond laser space shaping optical path;That is to say, using femtosecond laser space shaping technology and reasonable path planning, surface rectangular microgroove of large depth-width ratio under small size condition and various complex microgroove structure can be obtained on the surface of diamond, based on the absorption of protective layer, the phenomenon that diamond surface microgroove entrance width increases due to laser zoom is inhibited, based on this, the heterogeneous material welding of diamond and fused quartz is realized using femtosecond laser space shaping technology, the machining of diamond internal microchannel is realized, and the heat dissipation of high-frequency, high-power electronic chip is guaranteed.

[0019] 2. The application provides a kind of machining system of diamond internal microchannel based on femtosecond laser space shaping, by controlling different laser processing energy, the machining of diamond surface rectangular microgroove under different sizes can be realized, by reasonable planning of processing path, the machining of diamond surface patterned rectangular microgroove can be realized, the diamond internal microchannel of size accurately controlled, microchannel topography controllable, large depth-width ratio under small size is obtained, and the heat dissipation of next-generation high-power chip is guaranteed. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is the machining flowchart of diamond internal microchannel using femtosecond laser space shaping technology; Figure 2 It is the energy absorption diagram of polyimide protective layer; Figure 3 It is the optical path diagram of femtosecond laser space shaping technology; Figure 4 It is the path planning diagram of diamond surface straight microgroove and patterned microgroove; Figure 5 It is the machining result of diamond surface straight rectangular microgroove and patterned microgroove; Figure 6 It is the fixture used for welding diamond and fused quartz using femtosecond laser space shaping technology, the positional relationship of diamond and fused quartz and welding path schematic diagram; Figure 7 It is the machining result display of diamond internal microchannel. DETAILED DESCRIPTION

[0021] In order to enable the personnel in the art to better understand the scheme of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application.

[0022] A processing system of diamond internal micro-channel based on femtosecond laser spatial shaping, comprising a protective layer processing module, a micro-channel processing module, a cleaning module and a welding module. As shown in the figure, the protective layer processing module is used to add a polyimide protective layer on the surface of the diamond to be processed. Figure 1 It is to be noted that the diamond surface roughness used in the present application is less than 20nm, and the protective layer processing module first cleans the diamond with alcohol and deionized water solution for 5 minutes before adding the polyimide protective layer on the surface of the diamond to be processed.

[0023] The micro-channel processing module is used to process a micro-channel with a set pattern on the surface of the diamond to be processed with a polyimide protective layer according to a set processing path. Figure 2 As shown in the figure, as the focus of femtosecond laser moves down, the diameter of femtosecond laser beam becomes larger and larger, and the part of femtosecond laser with large diameter will contact the polyimide protective layer at this time, and the energy will be absorbed by the polyimide protective layer, so that this part of femtosecond laser is not enough to ablate the diamond, greatly reducing the inlet width increment.

[0024] The cleaning module is used to clean the remaining polyimide protective layer on the diamond with micro-channel processed, to obtain a diamond micro-channel embryo.

[0025] The welding module is used to weld fused quartz on the surface of the micro-channel of the diamond micro-channel embryo, to complete the packaging of the micro-channel. It is to be noted that laser welding needs to use a special welding fixture to realize the close contact of the diamond and the fused quartz, and the welding fixture is placed on the displacement table to focus the femtosecond laser on the contact plane of the two samples, and the welding process is carried out according to a specific welding path.

[0026] Further, the greater the thickness of the polyimide protective layer, the more energy of the femtosecond laser absorbed, and the smaller the increment of the entrance width of the micro-channel ablated by the femtosecond laser. For example, the present application adds a 0.05 mm thick polyimide to the surface of the diamond, which serves as a protective layer to eliminate the phenomenon of widening of the entrance of the micro-channel on the surface of the diamond. Specifically, when the femtosecond laser energy is constant during the machining process, the entrance width of the micro-channel ablated by the femtosecond laser is constant, and when the femtosecond laser energy changes during the machining process, the increment of the entrance width of the micro-channel ablated by the femtosecond laser is not completely the same, wherein the greater the femtosecond laser energy, the greater the increment of the entrance width of the micro-channel, and the smaller the femtosecond laser energy, the smaller the increment of the entrance width of the micro-channel.

[0027] Further, as shown in Figure 3 The micro-channel machining module includes a femtosecond laser (1), a mirror (2), a mirror (3), a half-wave plate (4), a polarization beam splitter (5), a mirror (6), an optical diffraction element (7), a quarter-wave plate (8), a mirror (9), a mirror (10), a dichroic mirror (11), a focusing objective lens (12), a three-dimensional displacement stage (14), a beam splitter (15), a white light source (16), and an imaging CCD (17), wherein the focusing objective lens is a 10x objective lens with a numerical aperture of 0.30, and the laser is a femtosecond laser with a central wavelength of 1030 nm, a pulse width of 290 fs, and a repetition frequency of 1000 Hz.

[0028] The micro-channel machining module is used to machine a micro-channel with a set pattern on the surface of a diamond to be machined having a polyimide protective layer according to a set machining path. Before ablation of the diamond with the femtosecond laser spot, the energy distribution of the femtosecond laser spot is first adjusted. The adjustment method is as follows: a fluorescent card is placed on the three-dimensional displacement stage, the position of the optical diffraction element (7) in the optical path is adjusted until the diffraction ring produced by the femtosecond laser on the fluorescent card covers the entire femtosecond laser spot; a beam quality analyzer is placed on the three-dimensional displacement stage, the femtosecond laser spot is vertically incident on the beam quality analyzer, and the position of the optical diffraction element (7) in the optical path is adjusted through the spot energy distribution on the computer connected to the beam quality analyzer until the uniformity of the energy of the femtosecond laser spot meets the requirements.

[0029] The femtosecond laser (1) generates femtosecond laser pulses, which pass through the mirror one (2), the mirror two (3), the half-wave plate (4), the polarization beam splitter (5), the mirror three (6), the optical diffraction element (7), the quarter-wave plate (8), the mirror four (9), the mirror five (10), are reflected by the dichroic mirror (11) after being focused by the focusing objective (12) to the diamond (13) surface to be processed with a polyimide protective layer, and the diamond (13) is fixed on the three-dimensional displacement table (14); the white light source (16) passes through the beam splitter (15) and the dichroic mirror (11), is reflected by the beam splitter (15) and is incident into the imaging CCD (17); According to the set processing path, the three-dimensional displacement table (14) is translated and moved up and down, so that the femtosecond laser spot is focused at different positions inside the diamond for ablation until the microchannel of the set pattern is obtained. Among them, the required microchannel of the diamond includes a surface straight microchannel and a patterned microchannel combined with curves and straight lines; the processing path of the surface straight microchannel is first transversely and then longitudinally, and is realized according to the processing method of sequentially circulating, the transverse and longitudinal moving distances are determined according to different laser processing parameters, the transverse moving distance of the displacement table ranges from 0.016 mm to 0.034 mm, and the longitudinal moving distance of the displacement table ranges from 0.03 mm to 0.13 mm; the processing path of the patterned microchannel is to realize closed loop scanning on the surface of the diamond according to the contour of the pattern in a specific direction, and then the displacement table is raised to increase the depth of the microchannel, and the raising distance of the displacement table ranges from 0.03 mm to 0.13 mm.

[0030] For example, the processing steps of the microchannel are as follows: Step 1: Adjust the position of the optical diffraction element in the optical path, and convert the laser into a flat-top beam from a Gaussian beam; adjust the angle of the quarter-wave plate, and convert the laser into circular polarization from linear polarization; wherein the angle of the quarter-wave plate is selected to be 45°, the pulse energy ranges from 5 to 50uj, and the scanning speed is 0.1 mm / s; Step 2: Plan the path according to the required microchannel structure; Step 3: Set the repetition frequency and energy of the laser, set the scanning speed, and perform femtosecond laser processing.

[0031] It should be noted that the processing parameters and the processing path need to be set before processing, and the processing parameters and the processing path corresponding to different structures are different, so here only the processing method of a 100um wide and 500um deep straight microchannel and a 100um wide and 500um deep patterned microchannel is listed. Adjust the laser energy so that the laser energy entering the objective 12 is 50 mw, and set the moving speed of the displacement table to 0.1 mm / s; for the processing path of the straight microchannel, such as Figure 4As shown in the left drawing, first, two parallel lines are arranged transversely on the diamond surface, and the interval is 0.034 mm; 6 times of the above two parallel lines are sequentially added in the longitudinal direction, and the longitudinal intervals are 0.13 mm, 0.09 mm, 0.09 mm, 0.09 mm, 0.09 mm and 0.09 mm respectively; for the processing path of the patterned micro groove, as shown in Figure 4 As shown in the right drawing, first, the contour curve of the required processing pattern is drawn by using CAD drawing software, and saved as a DXF file format, which is imported into the processing software, and the processing software will automatically generate the processing route, and a total of 7 times of scanning according to the contour curve in the longitudinal direction, and the longitudinal intervals are 0.13 mm, 0.09 mm, 0.09 mm, 0.09 mm, 0.09 mm and 0.09 mm respectively; after setting the processing parameters and the processing path, the diamond sample 13 is placed on the three-dimensional displacement table 14, and the surface structure is processed, and the processing result is as shown in Figure 5 .

[0032] In the light path used in the present application, first, the laser energy is adjusted, so that the laser energy entering the objective lens 12 is 50 mw, and the moving speed of the displacement table is 0.07 mm / s; according to the above-mentioned micro groove structure, the welding path is set, for the structure of a straight micro groove with a width of 100 um and a depth of 500 um, the welding path is as shown in Figure 6 the middle drawing, and the interval is 100 um, and the welding starting point is the edge of the sample to the midpoint of the first micro groove; for the structure of the patterned micro groove with a width of 100 um and a depth of 500 um, the welding path is as shown in Figure 6 the right drawing, the welding outer contour is 1.2 times larger than the processing outer contour, and the welding inner contour is 1.2 times smaller than the processing inner contour; after setting the processing parameters and the welding path, the welding jig as shown in Figure 6 the left drawing is used to make the diamond sample and the fused quartz in close contact, and then it is placed on the three-dimensional displacement table 14, so that the femtosecond laser is focused at the contact edge of the two samples, and the welding of the two samples is started, and the welding result is as shown in Figure 7 .

[0033] In summary, the present application provides a processing system for diamond internal micro flow channel based on femtosecond laser spatial shaping, first, based on the absorption of the protective layer, the phenomenon that the width of the micro groove inlet of the diamond surface increases due to laser zooming is inhibited; secondly, through the femtosecond laser hetero-material welding of the diamond and the fused quartz, the processing of the diamond internal micro flow channel can be realized; the present application adopts the femtosecond laser spatial shaping technology, realizes the processing of the diamond internal micro flow channel, and provides a guarantee for the heat dissipation of high-frequency and high-power electronic chips; that is, the present application can obtain a diamond internal micro flow channel with size controllable, controllable micro flow channel morphology and large depth-width ratio under small size, which provides a guarantee for the heat dissipation of the next generation of high-power chips.

[0034] Of course, the present application can have other various embodiments, and those skilled in the art can certainly make various corresponding changes and modifications according to the present application without departing from the spirit and essence of the present application, but these corresponding changes and modifications shall all belong to the protection scope of the claims attached to the present application.

Claims

1. A diamond internal microchannel processing system based on femtosecond laser spatial shaping, characterized in that, This includes a protective layer processing module, a microchannel processing module, a cleaning module, and a welding module; The protective layer processing module is used to add a polyimide protective layer to the surface of the diamond to be processed; The microchannel processing module is used to process microchannels with a set pattern on the diamond surface to be processed with a polyimide protective layer using a femtosecond laser according to a set processing path; wherein, the polyimide protective layer is used to absorb part of the energy of the femtosecond laser that comes into contact with the entrance of the microchannel when the femtosecond laser spot moves down along the depth direction of the diamond to ablate the microchannel, so that the remaining energy of the femtosecond laser that comes into contact with the entrance of the microchannel is lower than the ablation energy corresponding to the ablation threshold of the diamond. The cleaning module is used to clean the remaining polyimide protective layer on the diamond with microchannels to obtain a diamond microchannel preform. The welding module is used to weld fused silica onto the microchannel surface of the diamond microchannel preform, thereby completing the encapsulation of the microchannel.

2. The diamond internal microchannel processing system based on femtosecond laser spatial shaping as described in claim 1, characterized in that, The greater the thickness of the polyimide protective layer, the more energy the femtosecond laser absorbs, and the smaller the increase in the width of the microchannel inlet etched by the femtosecond laser.

3. The diamond internal microchannel processing system based on femtosecond laser spatial shaping as described in claim 1, characterized in that, If the thickness of the polyimide protective layer is the same in all regions of the diamond surface to be processed, then when the femtosecond laser energy is constant during the processing, the entrance width of the microchannels ablated by the femtosecond laser will be the same.

4. The diamond internal microchannel processing system based on femtosecond laser spatial shaping as described in claim 1, characterized in that, If the thickness of the polyimide protective layer is the same in all regions of the diamond surface to be processed, then when the femtosecond laser energy changes during the processing, the increment of the inlet width of the microchannel ablated by the femtosecond laser will not be exactly the same. Specifically, the higher the femtosecond laser energy, the larger the increment of the inlet width of the microchannel, and the lower the femtosecond laser energy, the smaller the increment of the inlet width of the microchannel.

5. The diamond internal microchannel processing system based on femtosecond laser spatial shaping as described in claim 1, characterized in that, Before adding a polyimide protective layer to the diamond surface to be processed, the protective layer processing module first cleans the diamond with alcohol and deionized water for 5 minutes each.

6. The diamond internal microchannel processing system based on femtosecond laser spatial shaping as described in claim 1, characterized in that, The method for cleaning the residual polyimide protective layer on the diamond with microchannels using the cleaning module is as follows: First, clean the diamond with microchannels using alcohol for 30 minutes, then clean the diamond with deionized water for 5 minutes.

7. The diamond internal microchannel processing system based on femtosecond laser spatial shaping as described in claim 1, characterized in that, The microchannel processing module includes a femtosecond laser (1), a first reflector (2), a second reflector (3), a half-wave plate (4), a polarizing beam splitter (5), a third reflector (6), an optical diffraction element (7), a quarter-wave plate (8), a fourth reflector (9), a fifth reflector (10), a dichroic mirror (11), a focusing objective (12), a three-dimensional displacement stage (14), a beam splitter (15), an illumination white light source (16), and an imaging CCD (17). The method by which the microchannel processing module processes a microchannel with a set pattern on a diamond surface with a polyimide protective layer using a femtosecond laser according to a set processing path is as follows: A femtosecond laser (1) generates a femtosecond laser pulse. The femtosecond laser pulse passes through mirror one (2), mirror two (3), half-wave plate (4), polarizing beam splitter (5), mirror three (6), optical diffraction element (7), quarter-wave plate (8), mirror four (9), and mirror five (10). After being reflected by dichroic mirror (11), it is focused by focusing objective lens (12) onto the surface of diamond (13) with polyimide protective layer. Diamond (13) is fixed on three-dimensional displacement stage (14). Illumination white light source (16) passes through beam splitter (15) and dichroic mirror (11), and is reflected by beam splitter (15) into imaging CCD (17). The three-dimensional displacement stage (14) is moved up and down according to the set processing path, so that the femtosecond laser spot is focused on different positions inside the diamond for ablation until the microchannel with the set pattern is obtained.

8. The diamond internal microchannel processing system based on femtosecond laser spatial shaping as described in claim 7, characterized in that, Before ablation of diamond using a femtosecond laser spot, the energy distribution of the femtosecond laser spot must first be adjusted. The adjustment method is as follows: Place the fluorescent card on the three-dimensional displacement stage and adjust the position of the optical diffraction element (7) in the optical path until the diffraction ring generated by the femtosecond laser on the fluorescent card covers the entire femtosecond laser spot. Place the beam quality analyzer on a three-dimensional displacement stage, so that the femtosecond laser spot is incident perpendicularly onto the beam quality analyzer. Then, adjust the position of the optical diffraction element (7) in the optical path according to the energy distribution of the spot on the computer connected to the beam quality analyzer until the uniformity of the femtosecond laser spot energy meets the requirements.

9. The diamond internal microchannel processing system based on femtosecond laser spatial shaping as described in claim 1, characterized in that, The microchannels required for diamond processing include straight microgrooves and patterned microgrooves that combine straight and curved surfaces. The processing path for straight microgrooves is first horizontal and then vertical. The processing path for patterned microgrooves is to perform a closed-loop scan on the diamond surface according to the outline of the pattern in a specific direction.

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