CN108526627A - A kind of semi-conducting material laser electrochemical copolymerization micro-processing method and device - Google Patents

Abstract

The invention discloses a semiconductor material laser electrochemical composite micromachining method and device, which belong to the field of special processing. The method uses the characteristic that the conductivity of semiconductor materials such as single crystal silicon increases significantly with the increase of temperature, and heats the semiconductor material by laser beams. Materials, enhance the electrical conductivity of the material near the processing area in a localized manner, and form a conductive channel through which the current passes preferentially. On this basis, electrolytic processing is introduced in the form of a biased electro-hydraulic beam to realize laser electrochemical "self-coupling" composite processing near the processing area. , no need for "knife setting", not only to ensure that there is no surface residue adhesion during laser processing, but also to strengthen the cooling effect, to reduce thermal damage, reduce residual stress, and improve the quality of the processed surface; the device includes a laser, an external optical path, electrolytic Power supply, stable jet generating device; the device can generate stable low-voltage electrolyte jet, and realize the adjustment of impact angle and position, so as to ensure the precise adjustment of the relative position between the laser beam and the impact jet.

Description

A semiconductor material laser electrochemical composite micromachining method and device

technical field

The invention relates to a processing method and device for processing structures such as micro-slits, holes, and grooves in the field of special processing, and in particular to a laser electrolytic composite processing method realized by utilizing the temperature sensitivity of the conductivity of semiconductor materials such as single crystal silicon and the like. device.

Background technique

Semiconductor materials represented by silicon and germanium have good structural and functional properties, and are widely used in chips, photovoltaics, medical devices, micro-electromechanical systems and other fields. Processing microstructures with specific morphology on the surface of semiconductor materials can achieve multiple functions, for example: submicron-scale periodic microgroove structure can enhance the anti-reflection performance of the material surface; honeycomb densely distributed smooth micropit groups can form microconcave lenses Array; the surface regular microstructure helps to change the hydrophilic properties of the material, and realizes superhydrophilic and superhydrophobic functions; the difference in hydrophilicity caused by different microtopography produces a difference in surface tension at the critical area, which can drive the autonomous movement of droplets .

Due to the high brittleness and low fracture toughness of semiconductor materials, the machinability of materials is poor, and micromachining is more difficult. Thanks to years of exploration by domestic and foreign scientific research institutions, gratifying progress has been made in the micromachining of such materials. At present, there are mainly microturning/milling processing, electrolytic processing, photolithography processing, chemical etching processing, laser processing, etc. The above processing methods have their own characteristics, applicable occasions and limitations. For example, when micro-end milling is used to process single crystal silicon, in order to ensure that material removal occurs in the ductile area to avoid cracks, it is necessary to control the single-step feed rate below 250nm, resulting in low material removal efficiency; At the same time, the process is more complicated, the requirements for lithography machines and other equipment are high, and different types of base materials with different crystal orientations have different requirements for etchant, so it is more suitable for stable metal materials, resulting in low processing efficiency; traditional laser processing of semiconductor materials is always accompanied by Large-scale production of obvious thermal damage; when using electrochemical dissolution method, limited by the characteristics of semiconductor materials, the current density is often lower than that of gold, and the advanced ultrafast laser represented by femtosecond laser has low removal efficiency. , expensive equipment and other deficiencies.

For the micromachining of semiconductor materials, some composite processing methods have been proposed at home and abroad, which combine mechanical force, laser, electrochemical anodic dissolution, electrochemical discharge, chemical corrosion, water jet impact and other means to achieve the purpose of micromachining.

After searching the existing technology, it was found that the scholar Tangwarodomnukun V et al. proposed a laser-water jet hybrid processing technology to realize micro-grooving processing of single crystal silicon materials in the article "Aninvestigation of hybrid laser-waterjet ablation of silicon substrates". This technology uses nanosecond pulsed laser to heat brittle materials, and the softened materials are then impacted and removed by biased high-pressure water jets, which can effectively avoid micro-cracks. At the same time, high-pressure jets have a forced cooling effect, which is conducive to thermal damage control. Unilateral thermal damage was controlled within 20 μm. However, this technology also has its own limitations, which are manifested in the roughness of the surface edge and inner wall of the microgrooves, and the large fluctuations in the depth of the groove bottom. At the same time, due to the intervention of high-pressure jet impact, there may be residual stress on the processed surface.

The US Patent Publication No. US2017/0120345A1 discloses a method and device for laser enhanced diamond drilling. In this method, diamond and other materials with high hardness and good light transmission are embedded in the core of the metal drill bit. During the processing, the laser can pass through almost non-destructively, irradiate the surface of the material to be processed, heat and soften the material near the contact area of the drill bit, and make the local hard and brittle. The material is transformed into a ductile material, which increases drilling efficiency, improves hole quality, and reduces tool wear. The method can be used to process hard and brittle materials such as ceramics and semiconductors, and realizes the production of 1mm drill bits. However, the diameter of the hole drilled by this method depends on the size of the drill bit, and the structure of the embedded diamond material in the drill bit makes the production more complicated, and it is difficult to further reduce the diameter of the drill bit, which may limit the application of this method in the field of micromachining.

The Chinese patent with publication number CN106735866A discloses a device and method for back-facing multi-focus laser and electrochemical composite processing of semiconductor materials. In this method, the parameter-adjustable laser beam is applied to the back of the semiconductor sample from bottom to top, and a large number of photogenerated holes are excited from the semiconductor sample, and the holes move to the surface of the semiconductor sample to participate in the electrochemical reaction, forming a material erosion remove. At the same time, the tool electrode is used as the cathode, and the semiconductor sample is used as the anode. By controlling the potential between the two electrodes, EDM at high potential and electrochemical erosion at low potential can be realized. In this method, the multi-focus laser and electrochemical compound act on the semiconductor sample, which can improve the etching efficiency and the surface quality of the through hole. However, in this method, the laser beam and the electrode must be accurately "knife-set" to achieve composite processing, which requires high device accuracy.

The Chinese patent with the publication number CN1919514A discloses a coaxial composite processing method of jetting liquid beam and laser. This method draws on the water-guided laser processing technology, and introduces a high-speed jetting liquid beam coaxial with the laser beam on the basis of laser processing. Electrolytic removal of material to eliminate recast layers, microcracks and residual stress. This method focuses on the high-quality and efficient processing of small holes, slots, slots and other structures with a size between 0.25mm and 1.5mm involved in aerospace, weaponry and other fields. It takes metal materials as the processing object and does not involve semiconductor materials. nature. In addition, limited to the diameter and quality of the jet, the beam quality will decrease during the coaxial transmission of the laser beam in the jet, which may cause the spot to diverge, making it difficult to further reduce the processing size.

Scholars Morin F J and Maita J P pointed out in the article "Electrical properties of silicon containing arsenic and boron" that in the temperature range between normal temperature and melting point of single crystal silicon, its electrical conductivity shows a trend of increasing sharply with increasing temperature (the electrical conductivity at 328 ° C About 25.6S/m, the conductivity at 1335°C is about 27372.2S/m). Based on this characteristic, if a local temperature field can be generated in the single crystal silicon material, the conductivity of the material can be locally enhanced, thereby realizing localized electrolytic processing of semiconductor materials. However, no relevant technical literature has been found.

Contents of the invention

Based on the characteristic that the conductivity of semiconductor materials such as silicon increases with temperature, the present invention proposes to use short-pulse laser irradiation to induce a localized conductivity-enhanced region near the processing area to form an instantaneous localized conductive channel through which current preferentially passes. Localized enhanced electrolysis; at the same time, the laser can ablate the passivation layer that may be generated in time, and continuously realize the coordinated processing of laser thermal effect and electrochemical anode dissolution self-coupling, so as to obtain a high processing efficiency, small thermal damage, and good surface quality. The microfabrication method of the method provides a special processing device for the method at the same time.

In order to achieve the above-mentioned purpose of the invention, the present invention is achieved through the following technical solutions:

A laser electrochemical composite micromachining method for semiconductor materials, which utilizes the characteristic that the conductivity of semiconductor materials increases with temperature, generates a local temperature field by focusing the laser beam, and introduces electrochemical anode dissolution at the same time, and dissolves in the laser and electrochemical anode Under the joint action of the laser, the recasting layer and residual stress can be effectively eliminated, and the processing quality can be improved; it is characterized in that the laser beam emitted by the laser is irradiated on the semiconductor material, and a metal thin film layer is arranged on the lower end surface of the semiconductor material; the metal thin film layer It is connected with the positive electrode of the DC pulse power supply, so that the potential of the lower surface of the semiconductor material is evenly distributed; the negative electrode of the DC pulse power supply is connected with the metal needle, so that the electrolyte in the metal needle is "cathodeized"; the electrolyte is on the semiconductor material A thin electrolyte layer is formed on the surface; the metal thin film layer is isolated from the outside world through an insulating layer, so that the localized conductive channel between the positive and negative electrodes of the DC pulse power supply only passes through the semiconductor material.

Further, the semiconductor material is a semiconductor material whose electrical conductivity is positively correlated with temperature, especially single crystal silicon.

Further, the electrolyte in the metal needle is a high-concentration neutral saline solution with a mass fraction of 25%-40%.

A semiconductor material laser electrochemical composite micromachining device, including an optical path system, a stable low-pressure jet flow generation and adjustment system, and an electrolytic processing system; the optical path system includes a laser, an optical gate, a beam expander, a vibrating mirror, and a mirror; The laser beam emitted by the laser passes through the optical gate, then passes through the beam expander, is reflected by two mirrors set at 45°, and then irradiates the semiconductor material through the vibrating mirror; the electrolytic processing system includes a DC pulse power supply, a metal film layer and an insulating layer; the metal thin film layer is arranged on the lower surface of the semiconductor material; the metal thin film layer is isolated from the outside world through the insulating layer, so that the localized conductive channel between the positive and negative electrodes of the DC pulse power supply can only be produced by the semiconductor material; the stable The low-pressure jet generation system includes a metal needle, and an electrolyte is passed through the metal needle, and the electrolyte forms a thin electrolyte layer on the upper surface of the semiconductor material.

Further, the stable low-pressure jet generation and adjustment system also includes a servo motor, a ball screw, an electrolyte cylinder and a piston rod; the servo motor is connected to the ball screw through a coupling; The block drives the piston rod to move left and right; the end of the piston rod is provided with a piston; the piston cooperates with the electrolyte cylinder; the electrolyte in the electrolyte cylinder enters the metal needle through the hose to form a smooth low-pressure jet.

Further, the electrolyte cylinder is equipped with a first one-way valve and a second one-way valve; when the servo motor rotates in the reverse direction, the ball screw drives the piston rod to retreat smoothly, the first one-way valve is closed, and the one-way valve The second opening, the electrolyte in the electrolyte tank enters the electrolyte cylinder through the filter under the action of the pressure difference; when the servo motor rotates forward, the ball screw drives the piston rod to advance steadily, the first one-way valve opens, the second The one-way valve is closed, and the electrolyte in the electrolyte tank is driven by the piston rod and enters the metal needle through the hose to form a smooth low-pressure jet.

Further, an angle adjuster is installed at one end of the metal needle, so that the impact angle of the jet can be adjusted, and the impact position of the jet can be adjusted by the XYZ three-way adjustment platform.

Further, it also includes an infrared camera, a high-speed camera, a hydrophone and a current probe; the signal changes detected by the current probe and the hydrophone are presented by an oscilloscope, and the imaging signals detected by the high-speed CCD camera and the infrared camera can be presented by a computer.

Further, the laser is a nanosecond or picosecond pulsed laser.

Further, the electrolyte recovery filter device is used for electrolyte recovery.

Beneficial effect:

(1) In view of the poor processing technology of semiconductor materials such as single crystal silicon, the conductivity of semiconductor materials such as single crystal silicon increases with the increase of temperature, and laser processing and electrochemical anodic dissolution are combined to achieve a A processing method with high processing efficiency, small thermal damage, and good surface quality solves the problems of small seams, holes, and holes with a size between 30 and 200 μm that exist in large quantities in the packaging and cutting of integrated circuit chips and the processing and manufacturing of micro-electromechanical system semiconductor micro-components. Difficulties in processing structures such as grooves.

(2) The present invention utilizes the sensitivity of the electrical conductivity of semiconductor materials such as monocrystalline silicon to temperature to convert the local high-temperature region generated by laser irradiation inside the material into a high-conductivity region, forming a localized conductive channel through which current preferentially passes , where the current density is much higher than the surrounding room temperature material area, thereby limiting the electrochemical anodic dissolution near the laser irradiation area, realizing the self-coupling cooperative processing of the laser thermal effect and the electrochemical anodic dissolution, and improving the processing localization. Improve the processing quality, and at the same time avoid the shortage of strictly relying on the "tool setting" step to achieve compound processing.

(3) The method of the present invention is based on laser processing, and at the same time rationally utilizes the characteristics that the conductivity of semiconductor materials such as single crystal silicon increases with temperature, and introduces electrolytic processing through a low-voltage electrolyte beam to realize laser processing and electrochemical anode dissolution Composite processing can not only ensure high processing efficiency, but also effectively reduce laser thermal damage and eliminate recasting layer and residual stress through electrochemical anodic dissolution. During the processing, the laser can ablate the possible passivation layer in time to ensure the continuous operation of electrolytic processing. At the same time, the impact of the low-voltage electrolyte beam on the adjacent position of the processing area, the surface of the material is subject to continuous forced cooling, which helps to further reduce thermal damage; in addition, laser irradiation induces plasma in the thin electrolyte layer above the processing area The body generates local strong micro-agitation through bubble collapse and other methods, which helps to take away the processed products, improve the flow field, and improve the processing quality.

(4) Utilize the localization of laser heating to form an instantaneous localized high temperature region along the laser beam axis in semiconductor materials such as single crystal silicon; use the impact electrolyte beam to introduce an external electric field near the processing area, and the current will take priority inside the material Through the enhanced conductivity region, an "instantaneous localized conductive channel" is formed, which realizes localized enhancement of current density and accelerates localized electrochemical anodic dissolution. In addition, within the laser pulse gap, due to the continuity of the temperature field change during the cooling process, the high-temperature area in the material will still exist for a period of time, and the localized electrolytic processing can be continued to achieve post-processing of the laser-processed surface to reduce thermal damage. The purpose of reducing residual stress and improving surface quality.

(5) The processing system of the present invention has perfect functions and is easy to assemble and realize. The designed stable low-pressure jet flow generation system has a simple structure and is easy to install and repair.

Description of drawings

Accompanying drawing 1 is the system schematic diagram of the laser electrolytic composite processing method that the present invention relates to;

Accompanying drawing 2 is the structure diagram of the stable low-pressure jet generation system involved in Fig. 1 of the present invention.

The reference signs are as follows:

1. Laser, 2. Laser beam, 3. Optical gate, 4. Beam expander, 5. Galvanometer, 6. Mirror, 7. Stable low-pressure jet generation and adjustment system, 8. Metal needle, 9. Thin electrolyte Layer, 10. Semiconductor material, 11. Insulation protection layer, 12. Metal film layer, 13. DC pulse power supply, 14. Current probe, 15. Localized conductive channel, 16. Hydrophone, 17. Oscilloscope, 18. Electrolysis Liquid recovery filter device, 19, high-speed CCD camera, 20, computer, 21, infrared camera, 8, metal needle, 22, jet angle regulator, 23, adjustable connecting rod, 24, hose, 25, first one-way Valve, 26, electrolyte cylinder, 27, piston, 28, piston rod, 29, slider, 30, ball screw, 31, first support seat, 32, servo motor, 33, coupling, 34, second Support seat, 35, second one-way valve, 36, electrolyte tank, 37, filter, 38, XYZ three-way adjustment platform.

Detailed ways

For doing further understanding to the present invention, now in conjunction with accompanying drawing, do further description:

Embodiment 1: This embodiment is a semiconductor material laser electrolytic composite processing method based on a localized conductive channel. The laser beam 2 generated by the laser 1 is adjusted and transmitted by an external optical path and then focused on the surface of the semiconductor material 10, and the thermal effect of the laser is used to process high-efficiency materials. Removal, complete micro-hole, micro-groove processing. At the same time, the thermal effect of the laser generates a local temperature field around the microholes, which locally enhances the conductivity of semiconductor materials such as single crystal silicon. On this basis, the stable low-voltage electrolyte beam generation and adjustment device is used to introduce a biased electrolyte beam, and in the region where the conductivity is enhanced around the laser irradiation area, electrochemical anodic dissolution is introduced locally, which can effectively eliminate the recast layer, Residual stress, improve processing quality. During composite processing, the thermal effect of the laser beam can destroy and eliminate the passivation layer that may be produced during electrolytic processing, ensuring continuous processing of composite processing.

The electrolyte is a neutral saline solution, which can also produce acidic solutions such as dilute hydrochloric acid; the neutral saline solution is a neutral saline solution with an appropriate concentration, and the mass fraction is 20%-40%; the dilute hydrochloric acid solution is 5%-15% by mass .

Embodiment 2: In combination with accompanying drawing 1, this embodiment is a semiconductor material laser electrolytic composite processing system based on a localized conductive channel, including an optical path system, a stable low-pressure jet generation and adjustment system, and an electrolytic processing system; the optical path system includes a laser 1 and an external The optical path, wherein the external optical path includes an optical gate 3, a beam expander 4, a vibrating mirror 5 and a mirror 6. The laser 1 outputs the laser beam 2, passes through the shutter 3 of the protection device, expands the diameter of the laser beam by the beam expander 4, adjusts the direction through the reflector 6, and finally controls the movement form of the beam by the vibrating mirror 5, irradiates the surface of the semiconductor material 10, and A localized conductive channel 15 is formed within the semiconductor material 10 . Both the generation of the laser beam 2 and the movement of the galvanometer 5 are controlled by the computer 20 .

This example also includes a stable low-pressure jet generation and adjustment system 7, the generated constant-speed electrolyte passes through the metal needle 8 to form a stable low-pressure jet, and impinges on the surface of the semiconductor material 10 to form a thin electrolyte layer 9.

In this example, an electrolyte recovery and filtering device 18 is also provided, which is beneficial to the recovery and utilization of the electrolyte.

This example also includes an electrolytic processing system, including a DC pulse power supply 13, the cathode of the power supply is connected to the metal needle 8 to make the jet "cathodeization", and the anode is connected to the metal thin film layer 12 on the lower surface of the semiconductor material 10, so that the potential of the lower surface is evenly distributed . The metal thin film layer 12 is covered with an insulating layer 11 to ensure that the conductive path between electrodes can only be generated through the semiconductor material 10 .

This example also includes a compound process detection system, including a current probe 14, a hydrophone 16, a high-speed CCD camera 19, and an infrared camera 21, wherein the signal changes detected by the current probe 14 and the hydrophone 16 can be presented by an oscilloscope 17, and the high-speed CCD Imaging signals detected by camera 19 and infrared camera 21 may be presented by computer 20 .

Embodiment 3: In combination with accompanying drawing 2, the embodiment is a stable low-pressure jet generation and adjustment system, including a servo motor 32 driving a ball screw 30 to rotate through a coupling 33, and the two ends of the ball screw 30 pass through the first support seat 32 and the second Supported by two supporting bases 35; the rotation of the ball screw 30 is converted into the linear motion of the piston rod 28 through the slider 29 matched with the ball screw 30, thereby pushing the electrolyte in the electrolyte cylinder 26 to output at a constant speed. The electrolyte flows into the metal needle 8 through the first one-way valve 25 and the hose 24 to form a stable low-pressure jet. The angle of the low-pressure jet can be adjusted by the angle regulator 22 , and the impact position of the jet can be adjusted by the XYZ three-way fine-tuning platform 38 . The first one-way valve 25 and the second one-way valve 35 can cooperate with the forward and reverse movement of the ball screw 30 to realize the electrolyte output and intake. When the servo motor 32 drives the piston rod 28 to move forward through the ball screw 30, the first one-way valve 25 is opened, the second one-way valve 35 is closed, and the electrolyte enters the hose 24 under the push of the piston 27; The ball screw 30 drives the piston rod 28 to move in reverse, the first one-way valve 25 is closed, the second one-way valve 35 is opened, and the electrolyte in the electrolyte tank 36 is sucked into the electrolyte tank 26 through the filter 37 .

work process:

Step 1, the servo motor 32 drives the piston rod 28 to retreat at a constant speed through the shaft coupling 33 and the ball screw 30, the first one-way valve 25 is closed, the second one-way valve 35 is opened, and the electrolyte in the electrolyte tank 36 is released under air pressure. Inhaled in the electrolyte cylinder 26 under the action of difference;

Step 2, the servo motor 32 drives the piston rod 28 to advance at a constant speed through the shaft coupling 33 and the ball screw 30, the first one-way valve 25 is opened, the second one-way valve 35 is closed, and the electrolyte in the electrolyte cylinder 26 is softened The tube 24 enters the metal needle 8, forming a steady electrolyte jet;

Step 3, the stable electrolyte jet impacts the surface of the semiconductor material 10, forming a thin electrolyte layer 9 with a stable thickness near the impact area; using the angle regulator 22 and the XYZ three-way adjustment platform 38 to adjust the position of the jet impact area;

Step 4, switch on the DC pulse power supply 13 to form an electrolytic machining current loop;

Step five, control the output of the laser beam 2 through the computer 20, adjust the radiation position of the laser beam to the vicinity of the impact position of the stable liquid beam through optical elements such as the beam expander 4, the mirror 6, and the vibrating mirror 5, and pass through the thin electrolyte layer 9 focus on the surface of semiconductor material 10;

Step 6, use the vibrating mirror 5 to control the movement of the laser beam, and process the required microstructures such as holes, grooves, and seams;

Step 7, during the processing, use high-speed CCD cameras 19, infrared cameras 21, current probes 14, hydrophones 16 and other detection instruments to observe phenomena such as heat and mass transfer, current changes, etc., thereby realizing the monitoring of the processing process;

Step 8, after the processing is finished, turn off the laser 1 and the DC pulse power supply 13, and stop the rotation of the servo motor 32;

The described embodiment is a preferred implementation of the present invention, but the present invention is not limited to the above-mentioned implementation, without departing from the essence of the present invention, any obvious improvement, replacement or modification that those skilled in the art can make Modifications all belong to the protection scope of the present invention.

Claims (10)

1. A laser electrochemical compound micromachining method for semiconductor materials, which uses the characteristic that the conductivity of semiconductor materials increases with temperature, generates a local temperature field by focusing the laser beam, and introduces electrochemical anode dissolution at the same time. Under the combined action of anode dissolution, the recast layer and residual stress are effectively eliminated, and the processing quality is improved; it is characterized in that the laser beam (2) emitted by the laser (1) is irradiated on the semiconductor material (10), and the semiconductor material ( 10) A metal thin film layer (12) is arranged on the lower end surface; the metal thin film layer (12) is connected to the positive electrode of the DC pulse power supply (13), so that the potential of the lower surface of the semiconductor material (10) is evenly distributed; the DC pulse power supply (13) ) is connected to the metal needle (8), so that the electrolyte in the metal needle (8) is "cathodeized"; the electrolyte forms a thin electrolyte layer (9) on the upper surface of the semiconductor material (10); the The metal film layer (12) is isolated from the outside world through the insulating layer (11), so that the localized conductive channel (15) between the positive and negative electrodes of the DC pulse power supply (13) only passes through the semiconductor material (10). 2 . The laser electrochemical composite micromachining method for semiconductor materials according to claim 1 , wherein the semiconductor material is a semiconductor material whose electrical conductivity is positively correlated with temperature, especially single crystal silicon. 3. The semiconductor material laser electrochemical composite micromachining method according to claim 1, characterized in that the electrolyte in the metal needle (8) is a high-concentration neutral saline solution with a mass fraction of 25%-40%. 4. A semiconductor material laser electrochemical composite micromachining device, comprising optical path system, stable low-pressure jet generation and adjustment system (7) and electrolytic processing system; it is characterized in that, described optical path system includes laser (1), optical gate ( 3), beam expander (4), vibrating mirror (5) and reflective mirror (6); the laser beam (2) that described laser (1) sends passes through after shutter (3), then passes through beam expander (4) ) after being reflected by two mirrors (6) set at 45°, and irradiated on the semiconductor material (10) through the vibrating mirror (5); ) and an insulating layer (11); the metal thin film layer (12) is arranged on the lower surface of the semiconductor material (10); the metal thin film layer (12) is isolated from the outside world by the insulating layer (11), so that the DC pulse power supply (13) The localized conductive channel (15) between the positive and negative electrodes can only be produced by the semiconductor material (10); the stable low-pressure jet generation system (7) includes a metal needle (8), and an electrolyte is passed through the metal needle (8). The electrolyte forms a thin electrolyte layer (9) on the upper surface of the semiconductor material (10). 5. semiconductor material laser electrochemical composite micromachining device according to claim 4, is characterized in that, described stable low-pressure jet generation and adjustment system (7) also comprise servomotor (32), ball screw (30), Electrolyte cylinder (26) and piston rod (28); Described servomotor (32) is connected with ball screw (30) by coupling (33); Described ball screw (30) is connected by slide block (29) ) drives the piston rod (28) to move left and right; the end of the piston rod (28) is provided with a piston (27); the piston (27) cooperates with the electrolyte cylinder (26); the electrolysis in the electrolyte cylinder (26) The liquid enters the metal needle (8) through the hose (24) to form a smooth low-pressure jet. 6. semiconductor material laser electrochemical composite micromachining device according to claim 5, is characterized in that, first check valve (25) and second check valve (35) are installed on described electrolyte cylinder (26) ); when the servo motor (32) rotates in the reverse direction, the ball screw (30) drives the piston rod (28) to retreat smoothly, the first one-way valve (25) is closed, the second one-way valve (35) is opened, and the electrolyte The electrolyte in the tank (36) enters the electrolyte cylinder (26) through the filter (37) under the action of the pressure difference; when the servo motor (32) rotates forward, the ball screw (30) drives the piston rod (28) Advance steadily, the first one-way valve (25) is opened, the second one-way valve (35) is closed, and the electrolyte in the electrolyte cylinder (26) enters the metal needle through the hose (24) under the push of the piston rod (28) (8), forming a smooth low-pressure jet. 7. The semiconductor material laser electrochemical composite micromachining device according to claim 5 or 6, characterized in that an angle adjuster (22) is installed at one end of the metal needle (8), so that the jet impact angle can be adjusted, and the jet The impact position is regulated by the XYZ three-way adjustment platform (38). 8. semiconductor material laser electrochemical composite micromachining device according to claim 4, is characterized in that, also comprises infrared camera (21), high-speed camera (19), hydrophone (16) and current probe (14); The signal changes detected by the current probe (14) and the hydrophone (16) are presented by the oscilloscope (17), and the imaging signals detected by the high-speed CCD camera (19) and the infrared camera (21) can be presented by the computer (20). 9. The semiconductor material laser electrochemical composite micromachining device according to claim 4, characterized in that the laser (1) is a nanosecond or picosecond pulse laser. 10. The semiconductor material laser electrochemical composite micromachining device according to claim 4, characterized in that the electrolyte recovery filter device (18) is used for electrolyte recovery.