CN116160121A - Quartz vibration beam processing method based on frequency multiplication Bessel laser selective etching - Google Patents
Quartz vibration beam processing method based on frequency multiplication Bessel laser selective etching Download PDFInfo
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Abstract
The invention discloses a quartz vibration beam processing method based on selective etching of frequency doubling Bessel laser, and belongs to the technical field of femtosecond laser application. The invention etches a resonator pattern on the gold film by utilizing photoetching and plasma etching processes on the double-sided gold-plated film of the Z-cut alpha quartz wafer, and the resonator pattern is used as a protective layer in the etching process and also serves as a surface electrode of a subsequent accelerometer; the femtosecond laser Gaussian beam is spatially shaped into a Bessel beam with long focal depth by using a conical lens, the Bessel beam is condensed by using a 4F system consisting of a plano-convex lens and a focusing objective lens, and is focused in a quartz wafer, and scanning processing is performed along the contour of the resonator pattern. After the Z-cut quartz crystal is irradiated by the femtosecond laser, the amorphous structure of the quartz crystal in the irradiation area is caused, the etching rate of the irradiation area in hydrofluoric acid solution is accelerated, and the etched sample falls off along the modified profile to obtain the quartz vibrating beam. The invention has the advantages of high verticality of the side wall of the vibration beam, good uniformity, no side erosion and the like.
Description
Technical Field
The invention relates to a method for selectively etching and processing a quartz vibrating beam resonator by frequency multiplication Bessel laser, belonging to the technical field of femtosecond laser application.
Background
The quartz vibration beam accelerometer is an acceleration sensing device which depends on the piezoelectric effect of quartz crystals and takes a force-sensitive quartz vibration beam resonator as a core sensitive element, has the characteristics of direct output of digital signals, no need of digital-to-analog conversion, simple structure, small volume, high sensitivity, high frequency stability and the like, and is an important component of an inertial instrument. The core component is a quartz resonance beam, and the working principle is that the mass block is used for converting the acceleration to be measured into inertia force to act on the resonance beam, the resonance frequency of the resonance beam is changed, and the resonance circuit is used for detecting the resonance frequency change and outputting digital signals.
The traditional processing technology of the quartz vibrating beam accelerometer resonator is a wet etching technology based on a photoetching technology, and the basic processing steps mainly comprise: and (3) obtaining a quartz resonance beam pattern by using a photoetching technology, and etching a through groove on the quartz wafer by using wet etching. The method needs a specific mask plate, the process is complex, and the anisotropy of the traditional wet etching can cause the non-uniformity of resonance Liang Keshi, namely side etching of the side wall and the corner of the vibration beam is easy to occur, and the performance of the vibration beam is influenced.
After the femtosecond laser is focused into the quartz crystal, the crystal structure of the irradiation area is changed, a modified area appears, the etching rate of the modified area in hydrofluoric acid solution is faster, and the characteristic can be utilized to realize the selective etching of the specific area. However, the unirradiated area is etched by hydrofluoric acid to a certain thickness, and the surface is easy to have defects such as pits. The invention combines the photoetching technology and the femtosecond laser processing technology, adopts the plating of chrome and gold films on the surface of the Z-cut alpha quartz wafer and utilizes the photoetching technology to etch out resonator patterns as a protective layer in the hydrofluoric acid etching process, thereby preventing the thinning of an unmodified area and the generation of surface defects. The femtosecond laser with the wavelength of 800+/-20 nm can obtain 400+/-5 nm femtosecond laser after being multiplied by a frequency multiplication crystal (BBO) and filtered, and compared with the former, the latter has smaller ablation threshold value on alpha quartz crystal and smaller spot size after focusing. The Bessel beam has the characteristics of long focal depth and no diffraction, after 400nm frequency multiplication femtosecond laser is shaped into the Bessel beam, the radius of the beam center is smaller than that of the original 800nm femtosecond laser, and the energy deposition efficiency is higher when the laser acts on the inside of a quartz crystal, so that large-depth and high-efficiency surface modification can be realized by matching with the movement of a sample, the modified surface penetrates through the upper surface and the lower surface of the quartz wafer, and then a modified area is etched and removed by utilizing hydrofluoric acid solution, so that the etching and cutting of the quartz wafer are realized. By means of the method, the frequency doubling Bessel beam is scanned and modified along the outline of the resonator pattern obtained through photoetching by controlling the motion of the precise three-dimensional electronic control translation stage, and the closed outline area falls off by means of subsequent etching of hydrofluoric acid solution, so that a resonant beam array is left on a quartz wafer.
Disclosure of Invention
In order to solve the problems of side etching defects, poor uniformity of the side wall of the quartz vibrating beam, low yield and the like caused by anisotropic etching characteristics of the traditional wet etching process of the quartz vibrating beam accelerometer resonator, the invention mainly aims to provide a method for selectively etching and processing the quartz vibrating beam by using frequency doubling Bessel laser, which can realize high-precision and high-side wall quality processing of the quartz vibrating beam, effectively eliminate the side etching defects and the like and improve the yield of the quartz vibrating beam.
The object of the present invention is achieved by the following technique.
The invention discloses a quartz vibration beam processing method based on frequency multiplication Bessel laser selective etching, which utilizes chromium plating and a gold film on the surface of a Z-cut alpha quartz wafer as a protective layer, and utilizes the property of frequency multiplication Bessel laser modification to realize hydrofluoric acid selective etching. Firstly plating chromium (Cr) with the thickness of 10-30 nm and gold (Au) with the thickness of 100-150 nm on the two sides of a quartz wafer, and then etching partial areas of the metal film by utilizing a photoetching technology and a plasma etching technology to expose areas of the quartz crystal to be etched, namely resonator patterns. And then, frequency doubling crystals (BBO) are adopted to multiply the femtosecond laser with the original wavelength of 800+/-20 nm of the laser into frequency doubling femtosecond laser with the central wavelength of 400nm, a band-pass filter is used for filtering to obtain wavelength components with the wavelength of 400+/-5 nm, then, the Gaussian-distributed femtosecond laser is spatially shaped into a diffraction-free Bessel beam with long focal depth, the Bessel beam after beam shrinking is focused in a quartz wafer sample, the movement of a translation table is controlled, the Bessel beam is enabled to scan a modified surface longitudinally penetrating through the quartz wafer in the quartz wafer, and the scanning track is the contour of a resonator pattern formed after the metal film is etched by the plasmas. By utilizing the characteristic that the etching rate of the quartz wafer modification area in hydrofluoric acid solution is accelerated, the selective etching of the specific modification area is realized, the etched surface penetrates through the upper surface and the lower surface of the quartz wafer, a closed contour part sample is fallen off after etching, a required resonator array is left on a quartz wafer substrate, and the high-precision and high-side wall quality processing of the quartz vibration beam is realized.
In order to ensure good adhesion between the gold film and the quartz substrate and the effect of plasma etching, it is preferable to plate chromium (Cr) with a thickness of 10nm and gold film (Au) with a thickness of 100nm on both sides of the quartz wafer.
In order to ensure the uniformity of the wavelength of the frequency multiplication laser, preferably, after the femtosecond laser with the original wavelength of 800+/-20 nm is frequency-multiplied, a band-pass filter with the wavelength of 400+/-5 nm is selected for filtering to obtain the frequency multiplication femtosecond laser with the wavelength of 400+/-5 nm.
The invention discloses a quartz vibration beam processing method based on frequency doubling Bessel laser selective etching, which comprises the following steps:
step one: respectively ultrasonically cleaning a Z-cut alpha quartz wafer sample with the thickness of 100-150 mu m and the side length of 20-40mm by adopting acetone, absolute ethyl alcohol and deionized water, drying the sample by utilizing compressed air, and plating a chromium film (Cr) and a gold film (Au) on the two sides of the quartz wafer sample in sequence by adopting a magnetron sputtering coating mode;
step two: respectively coating photoresist on two sides of an alpha quartz wafer sample in a suspension manner, and respectively photoetching photoresist resonator patterns on two sides of the alpha quartz wafer sample by utilizing a double-sided photoetching exposure and development technology; etching the gold (Au) and chromium (Cr) film layer exposed in the photoresist resonator pattern by using a plasma etching mode to expose the quartz substrate, thereby obtaining a resonator pattern with the gold-chromium film layer removed;
step three: constructing a frequency multiplication Bessel beam femtosecond laser processing system, wherein femtosecond laser with the wavelength of 400+/-5 nm is generated by frequency multiplication of 800+/-20 nm femtosecond laser through a frequency multiplication crystal (BBO), so as to obtain dual-wavelength mixed laser, and then filtering out 800nm wavelength components by using a band-pass filter, so as to obtain 400+/-5 nm femtosecond laser; the Bessel shaping device consists of a conical lens, a plano-convex lens and a focusing objective lens, wherein Gaussian femtosecond laser is shaped into a Bessel beam after passing through the conical lens, the plano-convex lens and the focusing objective lens jointly form a 4F beam shrinking system, and the Bessel beam formed after being shaped by the conical lens is further shrunk;
step four: fixing the Z-cut alpha quartz wafer sample with the gold-chromium film resonator pattern on a precise three-dimensional electric control translation table, focusing a frequency multiplication Bessel beam with the wavelength of 400nm inside the quartz wafer, and controlling the movement of the translation table to scan the Bessel beam along the contour of the resonator pattern, wherein the contour outline is a laser modification area;
step five: and respectively ultrasonically cleaning the processed quartz wafer sample by adopting acetone, ethanol and deionized water, drying by using compressed air, then placing in a hydrofluoric acid solution with the mass fraction of 5% for full etching until the modified profile is completely etched, removing a closed profile area, and leaving a Dan Yingzhen beam accelerometer resonator array on the quartz wafer sample.
Preferably, in step one, a thickness of 100 μm, 20X20mm, is selected 2 Ultrasonic cleaning is carried out on Z-cut alpha quartz wafer samples with the size by adopting acetone, absolute ethyl alcohol and deionized water respectively; the composite metal film selects a chromium film with the thickness of 10nm andthe gold film with the thickness of 100nm is used as an adhesion layer, so that the adhesion between the gold film and the quartz surface is increased, and the gold film is used as a protective layer for subsequent hydrofluoric acid etching and also as a final electrode of the quartz vibrating beam accelerometer resonator.
Preferably, the thickness of the SU-8 photoresist coated in the second step is 300nm, and the photoresist pattern and the gold film pattern etched by the plasma are the patterns of the areas to be removed of the resonator.
Preferably, the motion track of the translation stage in the fourth step is the contour of the pattern in the second step.
Preferably, the frequency doubling bessel beam femtosecond laser processing system in the third step comprises a femtosecond laser, an attenuation sheet set, an ultrafast reflector, a frequency doubling crystal (BBO), a band-pass filter (400+/-5 nm), a computer, a mechanical shutter, a conical lens, a plano-convex lens, a focusing objective lens, a dichroic mirror, a beam splitter, an illumination light source, a CCD imaging system, a precise three-dimensional electronic control translation stage, a manual pitching adjustment frame and a quartz wafer. The laser generated by the femtosecond laser controls the laser energy of a subsequent light path through an attenuation sheet group, the frequency multiplication of the femtosecond laser with the wavelength of 800+/-20 nm is carried out through a frequency multiplication crystal (BBO) to obtain mixed laser with the wavelength of 400nm and 800nm, the mixed laser is filtered through a bandpass filter to obtain frequency multiplication femtosecond laser with the wavelength of 400+/-5 nm, an ultrafast reflector controls the trend of the light path, a mechanical shutter controls the on-off of the light path, after the laser passes through a conical lens, a Gaussian beam is shaped into a Bessel beam, and after the Bessel beam passes through a 4f beam shrinking system consisting of the plano-convex lens and a focusing objective lens, the Bessel beam is shrunk to improve the energy density of the Bessel beam, and finally the Bessel beam is focused in a quartz wafer sample, the sample is fixed on a manual pitching adjusting frame, the level of the sample surface can be adjusted by utilizing the adjusting frame, and the laser focus is always positioned on the sample surface in the processing process; the white light source is arranged above the dichroic mirror, the white light irradiates the surface of the sample through the dichroic mirror, the reflected light on the surface of the sample is reflected into the CCD imaging system after passing through the focusing objective lens, the dichroic mirror and the beam splitter, so that the real-time detection of the sample processing process is realized, and the yield of the quartz vibration beam is ensured.
Preferably, the 400nm frequency-doubling light generating device in the third step comprises barium metaborate frequency-doubling crystal (BBO), and a band-pass filter (center wavelength 400nm, band-pass range 10 nm).
Preferably, the bessel beam-shaping device in step three includes a conic lens with a base angle of 2 °, a plano-convex lens with a focal length of 100mm, and a 50x focusing objective lens.
Preferably, the processing parameters in the fourth step are adopted to realize effective modification of the quartz wafer by the frequency doubling Bessel beam, ensure the processing precision of the outline of the resonance beam, realize effective etching in hydrofluoric acid solution, ensure that an etching surface penetrates through the quartz wafer, ensure the uniformity of modification, ensure the surface quality of the side wall surface of the resonance beam after etching, and avoid the occurrence of microcracks around a modification area caused by over-modification.
Preferably, the femtosecond laser frequency multiplication Bessel beam processing parameters are as follows: the pulse energy is 6-8 mu J, the laser central wavelength is 400nm, the pulse delay is 35fs, the scanning speed is 100-200 mu m/s, and the defocusing amount of the Bessel light beam light field center relative to the upper surface of the quartz wafer is 50-90 mu m.
Preferably, the etching agent in the fifth step is hydrofluoric acid solution with the mass fraction of 5%, and the etching condition is that the etching is performed for 10 hours at normal temperature.
Advantageous effects
1. According to the quartz vibration beam processing method based on frequency doubling Bessel laser selective etching, the chromium film (Cr) and the gold film (Au) are used as the protective layers, so that the laser unprocessed surface is protected from being etched by hydrofluoric acid when the alpha quartz crystal is etched in hydrofluoric acid solution, the high surface quality of a quartz wafer sample is maintained, and the thinning of the whole thickness of the sample can be avoided.
2. According to the quartz vibration beam processing method based on frequency multiplication Bessel laser selective etching, frequency multiplication is carried out on femtosecond laser with the wavelength of 800+/-20 nm by utilizing a frequency multiplication crystal (BBO), so that 400+/-5 nm femtosecond laser is obtained, the latter has a lower modification threshold value when the laser interacts with the quartz crystal, higher energy deposition efficiency is achieved, and the diameter of a focused central light field is smaller, so that high-efficiency processing with submicron size precision can be realized.
3. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching adopts a femtosecond laser auxiliary selective etching mode, so that the defects of side etching, convex edges and the like on the side wall caused by the traditional wet etching anisotropy are essentially overcome, and the processed side wall of the resonance beam is good in uniformity and high in surface quality. Compared with the original 800nm Bessel laser, the frequency multiplication Bessel laser has smaller diameter of the central light field, but the Bessel focal depth is unchanged, the depth-to-diameter ratio of the laser irradiation area is larger, and the processing precision is higher.
4. According to the quartz vibration beam processing method based on frequency doubling Bessel laser selective etching, disclosed by the invention, the movement of the three-dimensional electric control translation stage can be controlled through a computer, the processing track is regulated, and the flexible regulation of the size and the outline of the vibration beam can be realized.
Drawings
FIG. 1 is a flow chart of a quartz vibrating beam processing method based on selective etching of frequency-doubling Bessel laser;
FIG. 2 is a schematic diagram of a quartz vibrating beam processing method based on frequency doubling Bessel laser selective etching;
FIG. 3 is a schematic diagram showing the cross section of a quartz wafer sample and the variation of a chromium film and a gold film during the processing of the quartz vibration beam processing method based on frequency doubling Bessel laser selective etching;
FIG. 4 is a schematic diagram of the optical path of a frequency doubled Bessel beam femtosecond laser machining system;
FIG. 5 is a normalized intensity profile along the radial direction and a light field profile along the propagation direction for 400nm wavelength and 800nm wavelength Bessel beam light fields;
FIG. 6 is an optical microscopic imaging of a processed quartz resonant beam accelerometer resonator;
FIG. 7 is a scanning electron microscope image of a side wall of a resonant beam;
wherein: 1-femtosecond laser, 2-attenuation sheet set, 3-ultrafast reflector, 4-frequency doubling crystal (BBO), 5-bandpass filter, 6-computer, 7-mechanical shutter, 8-conical lens, 9-plano-convex objective lens, 10-focusing objective lens, 11-dichroic mirror, 12-beam splitter, 13-illumination light source, 14-CCD imaging system, 15-precise three-dimensional electric control translation stage, 16-manual pitching adjustment frame and 17-quartz wafer.
Detailed Description
The invention is further described below with reference to the drawings and examples.
Examples
As shown in fig. 1, the method for processing the quartz vibration beam based on selective etching of frequency-doubling bessel laser disclosed in the embodiment specifically comprises the following steps:
in the experimental processing process, the adopted femtosecond laser parameters are as follows: the initial femtosecond laser wavelength is 800+/-20 nm, the laser wavelength after frequency multiplication and filtering is 400+/-5 nm, the pulse width is 35fs, the pulse repetition frequency is 1kHz, the polarization state is linear polarization, and the focal depth length of the femtosecond laser frequency multiplication Bessel beam after beam contraction and focusing is about 220 mu m. The processed sample is 100 μm thick, 20x20mm 2 Is used for polishing the double-sided Z-cut quartz wafer.
Step one: 100 μm thick, 20X20mm 2 Ultrasonic cleaning is carried out on a Z-cut alpha quartz wafer sample with the size by adopting acetone, absolute ethyl alcohol and deionized water respectively, then the sample is dried by utilizing compressed air, and a chromium film (Cr) with the thickness of 10nm and a gold film (Au) with the thickness of 100nm are plated on the two sides of the quartz wafer sample in sequence by adopting a magnetron sputtering coating mode;
step two: respectively coating 300nm thick SU-8 photoresist on two sides of an alpha quartz wafer sample in a suspension manner, and respectively photoetching photoresist resonator patterns on the two sides of the alpha quartz wafer sample by utilizing a double-sided photoetching exposure and development technology; etching the gold (Au) and chromium (Cr) film layer exposed in the photoresist resonator pattern by using a plasma etching mode to expose the quartz substrate, thereby obtaining a resonator pattern with the gold-chromium film layer removed;
step three: the frequency multiplication Bessel beam femtosecond laser processing system is built and comprises a femtosecond laser 1, an attenuation sheet set 2, an ultrafast reflector 3, a frequency multiplication crystal 4 (BBO), a band-pass filter 5, a computer 6, a mechanical shutter 7, a conical lens 8, a plano-convex objective lens 9, a focusing objective lens 10, a dichroic mirror 11, a beam splitter 12, an illumination light source 13, a CCD imaging system 14, a precise three-dimensional electronic control translation stage 15, a manual pitching adjustment frame 16 and a quartz wafer 17. The method comprises the steps that after 800+/-20 nm femtosecond laser with the wavelength of 800+/-20 nm is subjected to frequency multiplication by a frequency multiplication crystal (BBO), 800nm and 400nm dual-wavelength mixed laser is obtained, 800nm wavelength components are filtered out by a band-pass filter, 400+/-5 nm femtosecond laser with the wavelength is obtained, wherein the energy of laser incident to the frequency multiplication crystal is controlled by an attenuation sheet group 2, the energy of the frequency multiplication 400nm femtosecond laser is further controlled, an ultrafast reflector 3 controls the trend of a light path, the on-off of the light path is controlled by a mechanical shutter 7, the intensity of laser energy is controlled by the attenuation sheet group 2 in the light path, 400nm wavelength frequency multiplication laser energy is regulated to a preset value and then enters a cone lens 8, a Gaussian beam is shaped into a Bessel beam, and after the Bessel beam passes through a 4f beam shrinking system consisting of a plano-convex lens 9 and a focusing objective lens 10, the Bessel beam is shrunk, the energy density of the Bessel beam is improved, and finally focused inside a quartz wafer sample 17, the sample is fixed on a manual pitching adjusting frame 16, the level of the sample surface can be adjusted by the adjusting frame, and the focal point of the sample surface in the processing process can be always located on the sample surface; the white light source 13 is arranged above the beam splitter 12, the white light irradiates the surface of the sample after passing through the beam splitter 12 and the dichroic mirror 11, and the reflected light on the surface of the sample is reflected into the CCD imaging system 14 after passing through the focusing objective lens 10, the dichroic mirror 11 and the beam splitter 12, so that the real-time detection of the sample processing process is realized.
Step four: an alpha quartz wafer sample with a quartz vibrating beam accelerometer resonator pattern is fixed on a precise three-dimensional electronic control translation stage, a frequency multiplication Bessel beam is focused in the quartz wafer, a resonator pattern profile numerical control code file generated in advance is operated through computer control software, the precise three-dimensional electronic control translation stage is controlled to move along a gold film resonator pattern profile, meanwhile, the movement speed of the translation stage is set within the range of 100-200 mu m/s, the energy of femtosecond laser pulses is adjusted to be 8-10 mu J by an attenuation sheet group, the defocusing amount of the Bessel beam center relative to the upper surface of the quartz wafer is set to be 50-90 mu m, and the Bessel beam is enabled to scan the resonator profile shape in the quartz wafer, namely a laser modification area.
Step five: and respectively ultrasonically cleaning the processed quartz wafer sample by adopting acetone, ethanol and deionized water, drying by using compressed air, and then placing in a hydrofluoric acid solution with the mass fraction of 5% for full etching until the modified profile is completely etched, namely separating quartz materials at two sides of the profile, and closing the profile area to fall off, thereby leaving a resonant beam array on the quartz wafer sample.
Step six: the scanning electron microscope is used for scanning electron imaging of the side wall of the quartz resonance beam, and the result shows that the processed resonance beam processing surface, namely the side wall has better uniformity, lower surface roughness, no side etching convex edges and other structures, and high yield.
According to the embodiment of the invention, the chromium film and the gold film are used as the protective layers, the unprocessed area of the alpha quartz wafer can be effectively prevented from being etched by hydrofluoric acid solution, the high quality of the surface is maintained, and secondly, the quartz vibrating beam resonator is processed by the mode of modifying the frequency doubling femtosecond laser Bessel beam and assisting chemical etching, so that the advantages of lower modification threshold value of the frequency doubling femtosecond laser on the quartz crystal, higher energy deposition efficiency and better quality of the processed side wall can be fully utilized, and meanwhile, the processing precision is higher. Compared with the traditional wet etching process, the method has the advantages that the processed resonance beam has no side etching easily occurring in the traditional etching process, the side wall has convex edges and the like, and the processed side wall has high surface quality and good uniformity.
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
Claims (9)
1. A quartz vibration beam processing method based on frequency multiplication Bessel laser selective etching is characterized by comprising the following steps:
step one: cleaning a Z-cut alpha quartz wafer sample, and plating a chromium film with the thickness of 10-30 nm and a gold film with the thickness of 100-150 nm on both sides to serve as a protective layer for subsequent hydrofluoric acid etching;
step two: etching part of the chromium film and the gold film by using a plasma etching technology of a photoetching process to obtain a quartz resonator pattern;
step three: the frequency doubling crystal BBO is utilized to multiply and filter the femtosecond laser with the wavelength of 800+/-20 nm to obtain the frequency-doubled laser with the wavelength of 400+/-5 nm;
step four: shaping the initial Gaussian distribution femtosecond laser into a long focal depth Bessel beam by using a conical lens, and condensing and focusing the Bessel beam by using a 4F system consisting of a plano-convex lens and an objective lens;
step five: focusing Bessel beams in the quartz wafer, and controlling a translation stage to scan along the contour of the resonator pattern obtained in the second step, wherein the contour is a laser modified surface penetrating through the upper surface and the lower surface of the quartz wafer;
step six: etching by using 5-10% hydrofluoric acid solution, removing the modified surface by etching, and removing the laser scanning profile to obtain the quartz vibrating beam structure.
2. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching as claimed in claim 1, wherein the method comprises the following steps: in the first step, preferably, the thickness of the chromium plating film on both sides of the quartz wafer is 10nm, and the thickness of the gold plating film is 100nm, and the quartz wafer is used as a hydrofluoric acid etching protective layer.
3. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching as claimed in claim 1, wherein the method comprises the following steps: in the second step, the mask pattern, namely the exposure area, is a resonator pattern, the photoresist is SU-8 photoresist, and the chromium film and the gold film in the exposure area are etched and removed in the plasma etching process to expose the quartz substrate.
4. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching as claimed in claim 1, wherein the method comprises the following steps: in the third step, the laser is frequency multiplication femtosecond laser with the wavelength of 400+/-5 nm, the frequency multiplication is carried out on the femtosecond laser with the wavelength of 800+/-20 nm through a frequency multiplication crystal BBO, and the laser is obtained after filtering through a band-pass filter (400+/-5 nm), and compared with the femtosecond laser with the initial center wavelength of 800nm, the laser has lower ablation threshold value on quartz crystals, stronger energy absorption and higher processing precision.
5. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching as claimed in claim 1, wherein the method comprises the following steps: in the fourth step, the cone lens is a cone lens with a base angle of 2 degrees, and the focal depth of the focal length Bessel beam of the plano-convex lens is 180-220 mu m after being focused by a 4F beam shrinking system.
6. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching as claimed in claim 1, wherein the method comprises the following steps: in the fourth step, the Bessel beam needs to select proper laser output power and repetition frequency, the repetition frequency is 1kHz, and the laser output power is 7-9mW.
7. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching as claimed in claim 1, wherein the method comprises the following steps: in the fifth step, the Bessel beam is focused into the quartz wafer, for the quartz wafer with the thickness of 100 μm, the defocus amount of the focal depth center of the Bessel beam from the upper surface of the quartz wafer is selected to be 50-80 μm, the number of scanning layers in the vertical direction is 1, the track is controlled by numerical control programming codes, and the movement speed of the translation stage, namely the laser scanning speed, is selected to be 150-250 μm/s.
8. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching as claimed in claim 1, wherein the method comprises the following steps: in the fourth step, preferably, the etchant is hydrofluoric acid solution, and the mass fraction is 5%.
9. The quartz vibration beam processing method based on frequency doubling Bessel laser selective etching as claimed in claim 1, wherein the method comprises the following steps: in the fourth step, the etching time of the processed quartz wafer in hydrofluoric acid is 10 hours.
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| CN116374947A (en) * | 2023-06-02 | 2023-07-04 | 中国工程物理研究院电子工程研究所 | Fused quartz cantilever beam-mass block structure and processing method thereof |
| CN116690199A (en) * | 2023-08-07 | 2023-09-05 | 湖南天羿领航科技有限公司 | Method and device for processing resonant structure of micro hemispherical gyroscope with skirt teeth |
| CN117226254A (en) * | 2023-11-02 | 2023-12-15 | 武汉华日精密激光股份有限公司 | Laser drilling device and method based on ultrafast laser-long pulse laser combination |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN116374947A (en) * | 2023-06-02 | 2023-07-04 | 中国工程物理研究院电子工程研究所 | Fused quartz cantilever beam-mass block structure and processing method thereof |
| CN116374947B (en) * | 2023-06-02 | 2023-08-25 | 中国工程物理研究院电子工程研究所 | Fused quartz cantilever beam-mass block structure and processing method thereof |
| CN116690199A (en) * | 2023-08-07 | 2023-09-05 | 湖南天羿领航科技有限公司 | Method and device for processing resonant structure of micro hemispherical gyroscope with skirt teeth |
| CN116690199B (en) * | 2023-08-07 | 2023-10-03 | 湖南天羿领航科技有限公司 | Method and device for processing resonant structure of micro hemispherical gyroscope with skirt teeth |
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