Device for carrying out ultrashort pulse laser trimming on chip resistor

Abstract

The invention relates to a device for carrying out ultra-short pulse laser trimming on a chip resistor, and belongs to the technical field of laser trimming resistance, and the device comprises a laser device which is used for generating initial laser which is an ultra-short pulse Gaussian spot; the beam expander is used for adjusting the diameter of the passed initial laser to a preset required diameter; the half-wave plate is used for adjusting the polarization direction of the passing initial laser to be horizontal polarization; the spatial light modulator is used for loading a set hologram and modulating initial laser into flat-topped light, and the flat-topped light acts on a machining area of the chip resistor in the light path direction; the monitoring module is used for acquiring the real-time resistance value of the chip resistor and sending the real-time resistance value to the control module; and the control module is used for controlling the laser emission work of the laser according to the relationship between the real-time resistance and the resistance threshold. According to the invention, the technical problems of large heat affected zone, poor groove morphology, micro-cracks and the like existing in laser resistance trimming of the chip resistor by using Gaussian light spots in the prior art are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser resistance trimming, and in particular to a device for trimming a chip resistor using ultrashort pulse laser. Background Art

[0002] As modern electronic information components continue to evolve towards miniaturization and monolithic integration, chip resistors, due to their numerous advantages, are widely used in various home appliances, electronic products, and smart cars. However, traditional trimming methods are increasingly unable to meet the precision and efficiency requirements of modern large-scale production. Laser trimming, with its high precision and non-contact characteristics, is becoming a key technology in this new era.

[0003] Due to the unique nature of chip resistor manufacturing, the initial resistance is often higher than the target value. Therefore, subsequent trimming processes (such as laser trimming) are required to precisely adjust the resistance to within a set range. Laser trimming utilizes a high-energy pulsed laser beam, focusing it into a tiny spot to precisely remove the printed paste from the resistor body. During this process, the removed resistor paste is instantly vaporized, effectively changing the shape and width of the resistor. Laser trimming offers advantages such as high precision, high efficiency, and low material consumption, and is gradually replacing traditional resistor trimming technologies.

[0004] Currently, Gaussian spot laser trimming is commonly used for laser resistance trimming. However, its uneven energy distribution leads to a large heat-affected zone (HAZ), poor cross-sectional morphology of the trimmed grooves, and defects such as microcracks. These defects lead to a poor temperature coefficient of resistance (TCR), increased resistance fluctuation with temperature, increased parasitic noise and voltage coefficient of resistance (VCR), and reduced resistor lifespan stability. Summary of the Invention

[0005] In view of this, it is necessary to provide a device for ultrashort pulse laser trimming of chip resistors to solve the technical problems in the existing technology of using Gaussian spot to perform laser trimming of chip resistors, such as large heat-affected zone, poor groove morphology and microcracks.

[0006] In order to solve the above problems, the present invention provides a device for ultrashort pulse laser trimming of chip resistors, comprising a control module, a monitoring module, and a laser, a beam expander, a half-wave plate, and a spatial light modulator connected in sequence along the laser light path;

[0007] The laser is used to generate initial laser light, and the initial laser light is an ultrashort pulse Gaussian spot;

[0008] The beam expander is used to adjust the diameter of the initial laser beam to a preset required diameter;

[0009] The half-wave plate is used to adjust the polarization direction of the passing initial laser light to horizontal polarization;

[0010] The spatial light modulator is used to load a set hologram and modulate the initial laser into a flat top light, and the flat top light acts on the processing area of the chip resistor along the optical path direction;

[0011] The monitoring module is used to obtain the real-time resistance value of the chip resistor and send the real-time resistance value to the control module;

[0012] The control module is used to control the laser emission operation of the laser according to the relationship between the real-time resistance value and the resistance threshold value.

[0013] In a possible implementation, a beam splitter prism is further included;

[0014] The beam splitter prism is arranged between the half-wave plate and the spatial light modulator along the laser light path direction, and is used to direct the initial laser light after passing through the half-wave plate to be incident on the spatial light modulator in a preset polarization direction.

[0015] In a possible implementation, a 4f optical path system is further included, and the 4f optical path system is arranged behind the spatial light modulator along the laser optical path direction; the 4f optical path system is used to transmit the flat-top light to the processing area of the chip resistor.

[0016] In a possible implementation, an objective lens is further included, which is arranged behind the 4f optical path system along the laser optical path. The objective lens is used to focus the flat-top light and transmit the focused flat-top light to the chip resistor processing area.

[0017] In one possible implementation, a Z-axis adjustment device is further included, which is arranged behind the spatial light modulator along the laser light path; the Z-axis adjustment device is used to adjust the focal position of the flat-top light so that the focus of the flat-top light acts on the chip resistor processing area.

[0018] In a possible implementation, a light spot analyzer is further included, wherein the light spot analyzer is used to collect the real-time peak value and real-time amplitude energy of the flat top light, and send the real-time peak value and real-time amplitude energy of the flat top light to the control module;

[0019] The control module is used to determine whether the real-time peak value and real-time amplitude energy of the flat top light meet the preset optimization requirements. If not, the hologram parameters are adjusted according to the real-time peak value and real-time amplitude energy of the flat top light.

[0020] In one possible implementation, the control module is also used to obtain the absorptivity curve of the resistance layer material at different wavelengths, and adjust the laser wavelength of the laser according to the absorptivity curve and preset optimization criteria; the optimization criteria include the size of the heat-affected zone, the uniformity of the groove cross-sectional morphology, and the generation of microcracks.

[0021] In one possible implementation, the control module is also used to obtain thickness information of the resistor material layer and compare the thickness information with a thickness threshold. When the thickness information is greater than the thickness threshold, the laser emitter is controlled to emit multiple low-energy lasers to process the resistor.

[0022] In a possible implementation, the control module is further configured to control the laser emitter to synchronously emit multiple laser beams.

[0023] In a possible implementation, a three-dimensional processing platform is further included, and the chip resistor to be processed is installed on the three-dimensional processing platform, and the three-dimensional processing platform can translate along the X and Y axes and rotate along the Z axis.

[0024] The beneficial effects of the present invention are as follows: the laser is controlled by the control module to emit an initial laser, the initial laser is adjusted to a preset diameter by a beam expander and then injected into a half-wave plate, the initial laser with the preset diameter is modulated into the required horizontal polarization direction by the half-wave plate and then reflected to the spatial light modulator, and the spatial light modulator modulates the horizontally polarized initial laser into a flat-top light with uniform energy distribution, the flat-top light acts on the processing area of the chip resistor along the optical path direction, and the chip resistor is processed with the flat-top light, which can optimize the problems such as severe heat-affected zone, poor trimming groove morphology, and microcracks caused by Gaussian light processing. Furthermore, the real-time resistance value of the chip resistor is obtained by the monitoring module and sent to the control module. The control module determines whether the chip resistor meets the requirements by comparing the real-time resistance value with the resistance threshold value. If the resistance requirement is met, the control module controls the laser to stop emitting the laser, thereby improving the efficiency of the resistance processing through real-time feedback from the monitoring module. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A system architecture diagram of an embodiment of a device for performing ultrashort pulse laser trimming on a chip resistor provided by the present invention;

[0026] Figure 2 A schematic diagram of the flat-top light modulation process in the device for performing ultrashort pulse laser trimming on a chip resistor provided by the present invention;

[0027] Figure 3 A schematic diagram of the resistor structure in the device for performing ultrashort pulse laser trimming on a chip resistor provided by the present invention;

[0028] Figure 4 This is a schematic diagram of flat-top multi-beam processing in the device for ultrashort pulse laser trimming of chip resistors provided by the present invention. DETAILED DESCRIPTION

[0029] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, and are not used to limit the scope of the present invention.

[0030] Before presenting the embodiments, the following terms are explained.

[0031] Chip resistor: Surface mount resistor, consisting of substrate, electrodes, resistor layer and transparent protective layer;

[0032] Ultrashort pulse laser: pulse width is picoseconds (10- 12 seconds) or femtoseconds (10- 15 Second-order lasers suppress heat diffusion. Furthermore, the main differences between short pulses (such as nanosecond lasers) and ultrashort pulses (such as picosecond and femtosecond lasers) lie in pulse duration and energy release rate. These characteristics determine their effectiveness in processing metal materials. In nanosecond pulses, the more concentrated laser energy can rapidly heat the metal surface to the evaporation temperature, causing the material to evaporate or melt. Short-pulse lasers have a relatively long action time, so the heat conduction effect is more significant, leading to localized thermal damage. During the trimming process, the laser heats the metal locally to a high temperature, partially evaporating or melting it. The molten metal, in turn, forms sputtering and slag due to surface tension effects, increasing the roughness of the processed surface. Ultrashort-pulse lasers have extremely short pulse widths (typically picosecond or femtosecond levels). Due to the ultrashort timescale and the laser intensity coupled to the electronic system, nonlinear absorption occurs only at the focal point, leaving little time for thermal diffusion of the metal to occur. This avoids heat conduction effects, resulting in highly localized material ablation or modification, ensuring high machining accuracy and cleanliness. The laser trimming solution, which combines the advantages of ultrashort pulse width and uniform energy distribution, can reduce the negative effects caused by various defects in traditional laser resistance trimming.

[0033] Beam expander: used to adjust the diameter of the laser beam and enlarge or reduce the input Gaussian spot to a preset size to meet the spot size requirements of different processing scenarios;

[0034] Hologram: A phase pattern generated by an SLM to modulate the light field distribution;

[0035] A specific embodiment of the present invention discloses a device for performing ultrashort pulse laser trimming on chip resistors. Figure 1, including a control module 1, a monitoring module 2, and a laser 3, a beam expander 4, a half-wave plate 5 and a spatial light modulator 6 connected in sequence along the laser light path;

[0036] The laser 3 is used to generate an initial laser, which is an ultrashort pulse Gaussian spot;

[0037] The beam expander 4 is used to adjust the diameter of the initial laser beam to a preset required diameter;

[0038] The half-wave plate 5 is used to adjust the polarization direction of the initial laser light to horizontal polarization;

[0039] The spatial light modulator 6 is used to load a set hologram and modulate the initial laser light into a flat top light, which acts on the processing area of the chip resistor along the optical path direction;

[0040] The monitoring module 2 is used to obtain the real-time resistance value of the chip resistor and send the real-time resistance value to the control module 1;

[0041] The control module 1 is used to control the laser emission of the laser 3 according to the relationship between the real-time resistance value and the resistance threshold value.

[0042] It should be noted that the selection and parameters of the laser 3 are not limited here. In this embodiment, the laser 3 used is an ultrashort pulse laser, specifically including a picosecond (10 -12 seconds) or femtoseconds (10 -15 The extremely short action time of ultrashort pulse lasers significantly reduces the heat conduction effect, avoids thermal damage to the resistor layer (such as microcracks and slag residue), and improves processing accuracy and resistor performance. In a specific embodiment, fiber lasers or solid-state lasers are preferred.

[0043] It should be noted that the beam expander 4 is composed of a pair of confocal lenses, including a concave lens (negative lens) and a convex lens (positive lens). The beam size is continuously adjusted by changing the distance between the two lenses. In other embodiments, a zoom lens group or a tunable liquid crystal lens can be used instead of the beam expander 4 to adjust the laser diameter.

[0044] It should be noted that the core function of the half-wave plate 5 is to change the polarization state of the light beam by phase delay. In some embodiments of the present invention, such as Figure 1 As shown, it also includes a beam splitter prism 7;

[0045] The beam splitter prism 7 is arranged between the half-wave plate 5 and the spatial light modulator 6 along the laser light path. The beam splitter prism 7 is used to direct the initial laser light after passing through the half-wave plate 5 to be incident on the spatial light modulator 6 in a preset polarization direction.

[0046] In an embodiment of the present invention, the laser energy and polarization state can be adjusted using two optical devices: a half-wave plate 5 and a PBS (beam splitter prism 7). This ensures that the laser polarization direction is perpendicular to the processing direction (e.g., the X-axis), is adjusted to horizontal polarization, and irradiates the reflective pure phase modulation spatial light modulator 6 at an incident angle of less than 10°. This configuration can improve the removal efficiency of the resistive layer material because horizontally polarized light can more efficiently couple the material to absorb energy during transverse cutting. Furthermore, the beam splitter prism filters out other polarization components to ensure the polarization purity of the incident light, while the laser energy is adjusted in conjunction with the half-wave plate.

[0047] It should be noted that the polarization direction is consistent with the processing direction of the workpiece. In other embodiments, the ideal polarization direction may be a vertical direction or other oblique directions.

[0048] It should be noted that the spatial light modulator 6 is mainly used to adjust the phase or amplitude of the light beam to achieve the purpose of modulating the phase of the laser, thereby generating a flat top light with uniform energy. Figure 2 As shown, a hologram is simulated by a spatial light modulator 6. The cylindrical mirror hologram shapes the Gaussian spot into a flat-top line spot, while the blazed grating offsets the zero-order light from the flat-top line light to prevent it from affecting the actual processing. The spatial light modulator 6 can be an SLM or other light field modulation device, such as a diffractive optical element, a deformable mirror, or liquid crystal on silicon.

[0049] In this embodiment, the control module 1 controls the laser 3 to emit an initial laser. The initial laser is adjusted to a preset diameter by the beam expander 4 and then incident on the half-wave plate 5. The initial laser with the preset diameter is modulated to the required horizontal polarization direction by the half-wave plate 5 and then reflected to the spatial light modulator 6. The spatial light modulator 6 modulates the horizontally polarized initial laser into a flat top beam with uniform energy distribution. The flat top beam acts on the processing area of the chip resistor along the optical path. Processing the chip resistor with the flat top beam can improve the problems caused by Gaussian light processing, such as severe heat affected zone, poor trimming groove morphology, and microcracks. Furthermore, the real-time resistance value of the chip resistor is obtained by the monitoring module 2 and sent to the control module 1. The control module 1 determines whether the chip resistor meets the requirements by comparing the real-time resistance value with the resistance threshold. If the resistance requirement is met, the control module 1 controls the laser 3 to stop emitting the laser, thereby providing real-time feedback through the monitoring module 2, thereby improving the efficiency of the resistance processing.

[0050] In order to improve the stability of laser propagation, some embodiments of the present invention further include a 4f optical path system 8, which is arranged behind the spatial light modulator 6 along the direction of the laser optical path; the 4f optical path system 8 is used to transmit the flat-top light to the processing area of the chip resistor.

[0051] It should be noted that in this embodiment, the SLM near-field image is transmitted through the 4f optical path system 8 composed of lens 1 and lens 2. The position of the flat-top light modulated by the SLM is limited and not suitable for processing. Free propagation will lead to a decrease in beam quality. The 4f optical path system 8 can ensure the beam quality of the flat-top light for long-distance propagation. The 4f system eliminates the beam divergence caused by free propagation through conjugate imaging, maintains the uniform energy distribution of the flat-top light, and reduces the heat-affected zone (HAZ) and microcracks. Furthermore, the 4f optical path system 8 cooperates with the SLM to solve the problem of beam distortion during long-distance transmission of the flat-top light.

[0052] In order to improve the accuracy of laser processing, some embodiments of the present invention further include an objective lens 9, which is arranged behind the 4f optical path system 8 along the direction of the laser optical path. The objective lens 9 is used to focus the flat-top light and transmit the focused flat-top light to the chip resistor processing area.

[0053] It should be noted that the objective lens 9 is capable of focusing the focus of the flat-top light. In this embodiment, the flat-top light can be processed more accurately by the objective lens 9 with a larger NA value. The larger the NA value of the objective lens 9, the smaller the focused spot, and the more precise the removal of the micro-nano structure. At the same time, the depth of focus will become smaller, and it will be more sensitive to the surface roughness of the processed material. If the surface roughness of the sample exceeds the depth of focus range, the processing effect will be unsatisfactory.

[0054] Therefore, in order to improve the processing accuracy when the surface roughness of the sample exceeds the focal depth range, some embodiments of the present invention further include a Z-axis adjustment device 10, which is arranged behind the spatial light modulator 6 along the direction of the laser light path; the Z-axis adjustment device 10 is used to adjust the focal position of the flat-top light so that the focus of the flat-top light acts on the chip resistor processing area.

[0055] In this embodiment, the focus can be moved up and down by the Z-axis adjustment device 10. For resistors with excessively rough surface, the focus can be moved so that the focus is always kept on the resistor surface.

[0056] In order to improve the processing efficiency, some embodiments of the present invention further include a light spot analyzer, which is used to collect the real-time peak value and real-time amplitude energy of the flat top light and send the real-time peak value and real-time amplitude energy of the flat top light to the control module 1;

[0057] The control module 1 is used to determine whether the real-time peak value and real-time amplitude energy of the flat top light meet the preset optimization requirements. If not, the hologram parameters are adjusted according to the real-time peak value and real-time amplitude energy of the flat top light.

[0058] In this embodiment, a spot analyzer (CCD camera and software) collects the real-time peak and amplitude energy distribution of the top-hat beam. Based on this collected data, the control module 1 modifies the hologram projected on the spatial light modulator 6. If the spot analyzer detects a top-hat beam appearing in the "one" direction, the spot length of the top-hat beam can be adjusted by adjusting the hologram's length parameter. If the left and right energy distribution of the top-hat beam is uneven, this can be adjusted by adjusting the hologram's offset parameter. If the energy distribution at the center and ends of the top-hat beam is uneven, this can be adjusted by adjusting the hologram's waist parameter: a larger waist indicates stronger energy in the center of the top-hat beam. Based on the data collected by the spot analyzer, the three parameters are adjusted to optimize the hologram until the spot energy distribution curve meets the processing requirements (uniform top-hat beam energy distribution). The hologram is then tested and verified through actual processing. Once verified, the values of the three parameter settings are recorded.

[0059] In a specific embodiment, the above steps are used to modulate flat-top lights with uniform energy distribution and lengths of 10 μm, 20 μm, 30 μm, 40 μm, and 50 μm, respectively, to meet the resistance adjustment requirements of different resistor products and the accuracy requirements of laser resistance adjustment. The damage thresholds of resistors of different materials are different during adjustment, and the energy required for laser resistance adjustment is different. It is only necessary to adjust the overall energy of the flat-top light. Increasing or decreasing the energy overall will not affect the energy distribution of the modulated flat-top light.

[0060] In some embodiments of the present invention, the control module 1 is also used to obtain the absorption rate curve of the resistance layer material at different wavelengths, and adjust the laser wavelength of the laser 3 according to the absorption rate curve and preset optimization criteria; the optimization criteria include the size of the heat-affected zone, the uniformity of the groove cross-sectional morphology and the generation of microcracks.

[0061] In this embodiment, the absorptivity curve of the resistor layer material at different wavelengths can be determined experimentally. Specifically, the wavelength absorptivity is divided into three ranges: low, medium, and high (usually comparing the three wavelength ranges of the infrared band, ultraviolet band, and visible light band), and three sets of comparative experiments are set as the basis. Preliminary experimental results are obtained by using an ultrashort pulse width laser to change laser process parameters such as the spot overlap rate, laser energy density, and laser repetition frequency. The experimental results are combined with the absorptivity curve, and the heat-affected zone (HAZ), groove cross-sectional morphology, microcracks, etc. are used as selection criteria to determine the laser with the appropriate wavelength range for resistance tuning (a current problem of laser resistance tuning technology). Based on the selected wavelength and ultrashort pulse width, the laser process parameters such as the spot overlap rate, laser energy density, and laser repetition frequency are further optimized. A larger spot overlap ratio can more effectively remove resistor layer material and create smoother sides and bottoms of the laser-trimmed grooves. It's recommended to conduct preliminary experiments with a spot overlap ratio of 60%-90% for resistors with thinner material layers (thick film <1µm), and 75%-95% for resistors with thicker material layers (thick film ≥1µm) to determine the appropriate spot overlap ratio. Given a fixed spot size (set based on the actual processing dimensions) and the same laser repetition rate, a larger overlap ratio requires a lower processing speed, which affects processing efficiency. Therefore, it's necessary to consider factors such as repetition rate and processing speed to ensure that the trimmed resistors meet production standards while maximizing production efficiency.

[0062] In some embodiments of the present invention, the control module 1 is also used to obtain thickness information of the resistor material layer and compare the thickness information with the thickness threshold. When the thickness information is greater than the thickness threshold, the laser emitter is controlled to emit multiple low-energy lasers to process the resistor.

[0063] In this example, see Figure 3 The chip resistor structure shown is targeted at resistors with thicker layers of resistive material (thick film ≥ 1μm). Low energy density lasers are insufficient to vaporize the substrate thick film material. When the laser energy density is too high, cracks will form in the resistor. Since cracks are one of the main defects affecting the final performance of the resistor, they should be avoided. Based on the effect of different laser energy densities on the processed resistor material, the control module 1 controls the laser emitter to emit lower energy densities (which have a material removal effect but cannot completely remove the entire resistor layer) to perform multiple variable focus processing on the resistor. That is, the laser focus position is determined during the initial processing, and then the laser focus position is adjusted accordingly based on the depth removed by each low energy until the resistor layer is completely removed. This step can be ignored for resistors with thinner layers of resistive material (thick film < 1μm).

[0064] In some embodiments of the present invention, the control module 1 is further configured to control the laser emitter to synchronously emit multiple laser beams.

[0065] In this embodiment, after confirming the laser parameters such as laser wavelength, pulse width, energy, repetition frequency, spot overlap rate, and number of scans, the spatial light modulator 6 is used to modulate a plurality of flat top lights that meet the processing requirements (the specific number depends on the number of scans). The spatial distribution of the flat top lights is as follows: Figure 4 As shown, assuming four top-hat beams (1, 2, 3, and 4 in the figure) are required and the processing direction is along the positive x-axis, the focus position of top-hat beam No. 1 is set as the processing focus. There is a processing direction difference (x-direction) between top-hat beams No. 1 and No. 2. Therefore, top-hat beam No. 1 first contacts the surface of the resistor layer to process and remove material. The removal depth is set to the focus difference between top-hat beams No. 1 and No. 2 (z-direction). At this time, the focus of top-hat beam No. 2 is exactly on the surface of the groove to be removed to a certain depth. Top-hat beams No. 3 and No. 4 are arranged in sequence according to this spatial distribution pattern, thereby realizing real-time detection of resistance value changes during laser trimming and improving processing efficiency.

[0066] It should be noted that laser resistance trimming requires a process of removing the resistor layer. Through a specific scanning path, the area through which the current passes is reduced, thereby increasing the resistance value. As mentioned earlier, removing layer by layer is a process of finding parameters. After the number of layers is determined, the flat-top light arranged in a specific space can completely remove the resistor layer material at one time along a specific route. The real-time resistance value of the resistance trimming process can be obtained based on the resistance-voltage-current relationship.

[0067] In some embodiments of the present invention, a three-dimensional processing platform is further included, and the chip resistor to be processed is installed on the three-dimensional processing platform, and the three-dimensional processing platform can translate along the X and Y axes and rotate along the Z axis.

[0068] In this embodiment, the resistor is mounted on a three-dimensional processing platform (translational motion on the X and Y axes and rotational motion on the U axis) below the objective lens 9 (used to focus the light spot and achieve energy convergence for processing). A real-time resistance monitoring instrument is installed on the resistor (see the optical path diagram: a power supply and a voltmeter are connected to the positive and negative terminals of the resistor. As the resistor layer is removed, the resistance value increases. When the desired resistance value is reached, the computer controls the laser to stop processing).

[0069] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A device for performing ultrashort pulse laser trimming on a chip resistor, characterized in that: It includes a control module, a monitoring module, and a laser, a beam expander, a half-wave plate and a spatial light modulator connected in sequence along the laser light path; The laser is used to generate initial laser light, and the initial laser light is an ultrashort pulse Gaussian spot; The beam expander is used to adjust the diameter of the initial laser beam to a preset required diameter; The half-wave plate is used to adjust the polarization direction of the passing initial laser light to horizontal polarization; The spatial light modulator is used to load a set hologram and modulate the initial laser into a flat top light, and the flat top light acts on the processing area of the chip resistor along the optical path direction; The monitoring module is used to obtain the real-time resistance value of the chip resistor and send the real-time resistance value to the control module; The control module is used to control the laser emission operation of the laser according to the relationship between the real-time resistance value and the resistance threshold value.

2. The device for performing ultrashort pulse laser trimming on a chip resistor according to claim 1, characterized in that: Also included is a beam splitter prism; The beam splitter prism is arranged between the half-wave plate and the spatial light modulator along the laser light path direction, and is used to direct the initial laser light after passing through the half-wave plate to be incident on the spatial light modulator in a preset polarization direction.

3. The device for performing ultrashort pulse laser trimming on a chip resistor according to claim 1, wherein: It also includes a 4f optical path system, which is arranged behind the spatial light modulator along the laser optical path direction; the 4f optical path system is used to transmit the flat-top light to the processing area of the chip resistor.

4. The device for performing ultrashort pulse laser trimming on a chip resistor according to claim 3, wherein: It also includes an objective lens, which is arranged behind the 4f optical path system along the laser optical path direction. The objective lens is used to focus the flat-top light and transmit the focused flat-top light to the chip resistor processing area.

5. The device for performing ultrashort pulse laser trimming on a chip resistor according to claim 1, wherein: It also includes a Z-axis adjustment device, which is arranged behind the spatial light modulator along the laser light path; the Z-axis adjustment device is used to adjust the focal position of the flat-top light so that the focus of the flat-top light acts on the chip resistor processing area.

6. The device for performing ultrashort pulse laser trimming on a chip resistor according to claim 1, wherein: It also includes a light spot analyzer, which is used to collect the real-time peak value and real-time amplitude energy of the flat top light and send the real-time peak value and real-time amplitude energy of the flat top light to the control module; The control module is used to determine whether the real-time peak value and real-time amplitude energy of the flat top light meet the preset optimization requirements. If not, the hologram parameters are adjusted according to the real-time peak value and real-time amplitude energy of the flat top light.

7. The device for performing ultrashort pulse laser trimming on a chip resistor according to claim 1, wherein: The control module is also used to obtain the absorptivity curve of the resistance layer material at different wavelengths, and adjust the laser wavelength of the laser according to the absorptivity curve and preset optimization criteria; the optimization criteria include the size of the heat-affected zone, the uniformity of the groove cross-sectional morphology, and the generation of microcracks.

8. The device for performing ultrashort pulse laser trimming on a chip resistor according to claim 1, wherein: The control module is also used to obtain thickness information of the resistor material layer and compare the thickness information with a thickness threshold. When the thickness information is greater than the thickness threshold, the control module controls the laser emitter to emit multiple low-energy lasers to process the resistor.

9. The device for performing ultrashort pulse laser trimming on a chip resistor according to claim 1, wherein: The control module is also used to control the laser emitter to synchronously emit multiple laser beams.

10. The device for performing ultrashort pulse laser trimming on a chip resistor according to any one of claims 1 to 9, characterized in that: It also includes a three-dimensional processing platform, on which the chip resistor to be processed is installed. The three-dimensional processing platform can move translationally along the X and Y axes and rotate along the Z axis.

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