阅读说明：本技术 兆瓦级光导半导体器件及电极连接与绝缘封装方法 (Megawatt photoconductive semiconductor device and electrode connection and insulation packaging method ) 是由 荀涛 楚旭 赵昱鑫 伍麒霖 王日品 王朗宁 杨汉武 贺军涛 张军 于 2020-05-25 设计创作，主要内容包括：本发明具体涉及一种光子微波用兆瓦级光导半导体器件及电极的连接与绝缘封装方法。由绝缘封装盒、正电极、负电极、第二固定板、宽禁带光导半导体晶圆组成。本发明以光导半导体绝缘封装盒为主体结构,通过电极涂敷与绝缘胶灌封,很好的解决了微米级光导半导体器件和外接电极的欧姆接触和耐高压绝缘问题。通过优化电极结构,改进涂敷、灌封方式等措施,解决了光导半导体器件与外接电路的欧姆接触问题,大幅度减少了光导半导体器件的欧姆接触阻抗,同时也保证了欧姆接触的稳定性。本发明可以有效提高在几十ns脉宽、几十kV量级重复频率脉冲高压条件下,光导半导体器件的耐压绝缘特性和系统整体紧凑化程度,实现兆瓦量级光子微波输出。(The invention relates to a megawatt photoconductive semiconductor device for photonic microwave and a method for connecting and insulating and packaging electrodes. The device consists of an insulating packaging box, a positive electrode, a negative electrode, a second fixing plate and a wide bandgap photoconductive semiconductor wafer. The invention takes the photoconductive semiconductor insulating packaging box as a main structure, and well solves the problems of ohmic contact and high-voltage insulation of a micron-sized photoconductive semiconductor device and an external electrode through electrode coating and insulating glue encapsulation. By optimizing the electrode structure and improving the measures of coating, encapsulating and the like, the ohmic contact problem of the photoconductive semiconductor device and an external circuit is solved, the ohmic contact impedance of the photoconductive semiconductor device is greatly reduced, and the stability of ohmic contact is ensured. The invention can effectively improve the voltage-resistant insulating property of the photoconductive semiconductor device and the overall compactness of the system under the conditions of dozens of ns pulse width and dozens of kV magnitude repetition frequency pulse high voltage, and realizes the output of megawatt magnitude photon microwave.)

1. A megawatt-level photoconductive semiconductor device, comprising: the device consists of an insulating packaging box (1), a positive electrode (2), a negative electrode (3), a second fixing plate (5) and a wide bandgap photoconductive semiconductor wafer (6); the insulating packaging box (1) is a hollow cube, a deep groove is formed in one side face of the cube, the positive electrode (2) and the negative electrode (3) are clamped in the deep groove through grooves formed in the upper surface and the lower surface of the left side of the L-shaped I, and then the positive electrode and the negative electrode are pressed and fixed by a second fixing plate (5) with a bulge in the middle; the positive electrode (2) and the negative electrode (3) are in a shape like a Chinese character 'ji', hollow cylindrical contact electrodes are arranged at the right end of the shape like the Chinese character 'ji', and the wide bandgap photoconductive semiconductor wafer (6) is compacted and electrically contacted well through the two hollow cylindrical contact electrodes; electrode pins are arranged at the lower end of the horizontal line and the vertical line so as to be convenient for connecting an external circuit; threaded holes are formed in the crossed positions of the Chinese character 'factory' shapes, and the compression degree between the two hollow cylindrical contact electrodes is adjusted through fastening screws penetrating through the threaded holes; the hollow part of the cube is filled with insulating pouring sealant, so that the two contact electrodes and the wide bandgap photoconductive semiconductor wafer (6) are ensured to be immersed in the insulating pouring sealant, and the occurrence of electric breakdown is prevented.

2. A megawatt-level optical semiconductor device in accordance with claim 1, wherein: the semiconductor device is also provided with a first fixing plate (4), and the positive electrode (2) can be fixed on the other side of the insulating packaging box through the first fixing plate (4) according to the circuit connection requirement.

3. A megawatt-level optical semiconductor device in accordance with claim 1, wherein: the insulating packaging box (1), the first fixing plate (4), the second fixing plate (5) and the fastening screw are all made of nylon or polytetrafluoroethylene, and the positive electrode (2) and the negative electrode (3) are all made of brass.

4. A megawatt-level optical semiconductor device in accordance with claim 1, wherein: the wide-bandgap photoconductive semiconductor wafer (6) is a SiC wide-bandgap photoconductive semiconductor wafer coated with a zinc oxide transparent electrode.

5. A megawatt optical semiconductor device according to any one of claims 1 to 4, wherein:the structure size of the semiconductor device is as follows: r₁＝3.0mm，R₂＝3.0mm，R₃＝2.0mm，R₄＝3.0mm，R₅＝5.5mm，R₆＝2.5mm，R₇＝3.5mm，R₈＝0.2mm，R₉＝0.7mm，R₁₀＝3.0mm，R₁₁＝1.0mm，R₁₂＝1.6mm，R₁₃＝2.0mm，R₁₅＝2.0mm，Φ₁₄＝4.0mm，R₆₁＝2.5mm，R₇₁＝3.5mm，R₈₁＝0.2mm，R₉₁＝0.7mm，R₁₀₁＝3.0mm，R₁₁₁＝1.0mm，Φ₁₂₁＝3.2mm，R₁₃₁＝2.0mm，R₁₅₁＝2.0mm，Φ₁₄₁＝4.0mm，R₁₆＝1.75mm，R₁₆₁＝1.75mm，L₁＝30.0mm，L₂＝27.0mm，L₃＝42.0mm，L₄＝20.0mm，L₅＝22.0mm，L₆＝17.0mm，L₇＝2.3mm，L₈＝12.5mm，L₉＝5.0mm，L₁₀＝8.0mm，L₁₁＝7.5mm，L₁₂＝7.5mm，L₁₃＝3.5mm，L₁₄＝3.0mm，L₁₅＝5.0mm，L₁₆＝20.0mm，L₁₇＝5.0mm，L₁₈＝2.5mm，L₁₉＝3.0mm，L₂₀＝18.5mm，L₂₁＝3.0mm，L₂₂＝8.0mm，L₂₃＝9.0mm，L₂₄＝21.0mm，L₂₅＝2.5mm，L₂₆＝10.0mm，L₁₃₁＝3.5mm，L₁₄₁＝3.0mm，L₁₅₁＝5.0mm，L₁₆₁＝20.0mm，L₁₇₁＝5.0mm，L₁₈₁＝2.5mm，L₁₉₁＝3.0mm，L₂₀₁＝18.5mm，L₂₁₁＝3.0mm，L₂₂₁＝8.0mm，L₂₃₁＝9.0mm，L₂₄₁＝21.0mm，L₂₅₁＝2.5mm，L₂₆₁＝10.0mm，L₂₈＝20.0mm，L₂₉＝5.0mm，L₃₀＝5.0mm，L₃₁＝5.0mm，L₂₈₁＝20.0mm，L₂₉₁＝5.0mm，L₃₀₁＝5.0mm，L₃₁₁＝5.0mm，H₁＝30.0mm，H₂＝5.0mm，H₃＝20.0mm，H₄＝5.0mm，H₆＝3.0mm，H₇＝5.3mm，H₆₁＝3.0mm，H₇＝7.0mm。

6. A method for connecting and insulating and packaging an external electrode of an optical semiconductor device according to claim 1, wherein: the method mainly comprises eight steps of electrode coating treatment, conductive silver adhesive preparation, external electrode coating, inter-electrode ohmic contact, ohmic contact metallization, insulating pouring sealant preparation, insulating pouring sealant defoaming treatment and insulating pouring sealant curing, and the specific implementation mode is as follows:

(S1) electrode application: firstly, carrying out air dust removal on an electrode-coated area of a wide-bandgap photoconductive semiconductor wafer, and carrying out micro-wiping treatment on the electrode-coated area by using 4009A antistatic optical dust-free cloth and acetone; finally, the wide-bandgap photoconductive semiconductor wafer is placed in a dust-free vacuum drying oven for drying treatment;

(S2) conductive silver paste preparation: the type of the used conductive silver adhesive is EPO-TEK/H20E, and the conductive silver adhesive consists of two components A and B; a, B taking out the conductive silver colloid of the two components, weighing A, B with a precise electronic scale respectively to ensure the consistent weight, pouring A, B with consistent weight into a clean blending dish, and stirring fully and uniformly;

(S3) external electrode coating: uniformly coating the prepared conductive silver adhesive in the step S2 on the annular contact surfaces of the positive and negative electrode hollow cylindrical contact electrodes;

(S4) electrode ohmic contact: the annular surface of the wide-bandgap photoconductive semiconductor wafer, which is coated with the electrodes, is ensured to be coaxial with the annular surfaces of the positive electrode and the negative electrode, the fastening screw is adjusted to fasten the ohmic contact between the wide-bandgap photoconductive semiconductor wafer electrode and the hollow cylindrical contact electrodes of the positive electrode and the negative electrode, and the second fixing plate 5 is adjusted to further reinforce the ohmic contact of the wide-bandgap photoconductive semiconductor wafer electrode;

(S5) ohmic contact metallization: putting the whole insulated packaging box assembled with the positive electrode, the negative electrode and the wide bandgap photoconductive semiconductor wafer into a vacuum drying box for drying; after the temperature in the drying oven is naturally cooled, injecting pure dry nitrogen into the vacuum drying oven, and taking out the nitrogen when the pressure is balanced with the room pressure;

(S6) preparing an insulating pouring sealant: the type of the used insulating pouring sealant is SYLGARD 184, the preparation ratio of the used main agent to the used auxiliary agent is 1:10, the main agent and the auxiliary agent are placed in a clean container vessel and are stirred uniformly until the main agent and the auxiliary agent are mixed fully;

(S7) defoaming the insulating pouring sealant: placing the uniformly mixed insulating pouring sealant in a vacuum box, performing vacuum air exhaust by using a vacuum pump, and taking out the insulating pouring sealant after all bubbles in the insulating pouring sealant are removed;

(S8) curing the insulating pouring sealant: pouring the defoamed insulating pouring sealant into the hollow part of the insulating packaging box, so that the positive electrode, the negative electrode and the wide-bandgap photoconductive semiconductor wafer are immersed in the insulating pouring sealant, then carrying out vacuum defoaming on the insulating packaging box poured with the insulating pouring sealant again, and then placing the insulating packaging box in a vacuum drying box for high-temperature curing; and after the temperature in the box is naturally cooled, taking out the box to obtain the final photoconductive semiconductor device.

Technical Field

The invention relates to the fields of optical technology, pulse power technology, high-power microwave technology and the like, in particular to a megawatt photoconductive semiconductor device for photon and microwave and a method for connecting and insulating and packaging electrodes.

Background

Photoconductive semiconductor devices are one of the key components in the field of pulse power technology for generating high power ultrashort picosecond pulses. The optical waveguide device has not only the advantage of a compact structure of a solid device but also its own unique advantages such as extremely fast on-time (picosecond magnitude), extremely small time jitter (picosecond magnitude), excellent synchronization accuracy (picosecond magnitude), low on-inductance (subnanohenry), photoelectric isolation, and the like. In particular, light guide devices have promising developments in terms of both power capacity (hundreds of megawatts) and repetition frequency (kilohertz). The unique advantages enable the photoconductive semiconductor device to have wide application prospects in the field of pulse power research such as solid compact pulse power sources, high-power ultra-wideband microwave radiation sources, dielectric wall accelerators, trigger systems of large pulse power devices, terahertz radiation and the like. With the development of science and technology, especially the rise of photoelectric technology, microwave technology and laser technology, people put higher and higher requirements on performance indexes of optical semiconductor devices, such as response speed, volume weight, working precision, power capacity, on-resistance and the like. At present, the generation mode of high-power and even high-power microwaves is being changed from a traditional electric vacuum device to a solid-state device, and the adoption of a wide-bandgap photoconductive semiconductor to generate radio frequency and microwaves with adjustable parameters is a brand new attempt and has important application prospects. Compared with the application of an ultra-wideband source and a compact pulse power system, the photoconductive semiconductor device made of the SiC material has good practicability because of the excellent characteristics of wide forbidden band, high critical breakdown electric field, high carrier mobility, high electron saturation drift velocity, high heat conductivity and the like.

A wide bandgap photoconductive semiconductor wafer is generally composed of a pair of electrodes and a photoconductive wafer substrate. A bias voltage is applied to the electrodes, and incident light irradiates the wafer substrate to generate a photoconductive current between the two electrodes. The wide bandgap photoconductive semiconductor wafer can be classified into a coplanar type and an out-of-plane type according to the position of the electrode. For the same-surface type, the electrodes are positioned on the same surface of the wafer, the manufacturing is simple, the incident direction of the trigger light is vertical to the moving direction of the current carrier, and the corresponding speed is high. However, since the electrodes are on the same surface of the wafer, local strong current on the surface is easily formed, which causes surface breakdown, and the insulation strength is low, so that it is difficult to achieve a high power capacity of the device. Compared with the coplanar electrode structure, the two electrodes of the switch are respectively positioned at the upper side and the lower side of the wafer substrate, the body conduction of the device can be realized, the excellent characteristics of the photoconductive material are fully exerted, and the structure is compact. In order to fully utilize the excellent characteristics of the wafer substrate, the hetero-surface type optical waveguide structure needs to realize good electrode contact and insulation packaging. In the aspect of optical semiconductor materials, the main defects are that the mechanical strength is poor, the voltage resistance is poor, the requirement on high-voltage insulation is high, the adoption of an insulation packaging technology is beneficial to enhancing the mechanical strength of the materials, and the reduction of the service life of the materials caused by voltage flashover is avoided. In the aspect of contacting the electrodes, higher requirements are placed on ohmic contact between the electrodes and the semiconductor material and connection stability of an external circuit. Therefore, while the physical properties of the photoconductive semiconductor device are studied, the electrode ohmic contact process, the overall package connection design of the semiconductor device, and the high-voltage insulation encapsulation technology are also studied. The photoconductive semiconductor device subjected to insulation packaging and electrode optimization is used as an important module of a pulse power system, can be applied to the technical fields of a high-current accelerator, a pulse power system, a high-power microwave source and the like, has better military and industrial benefits, but has no related technical scheme at present.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the photoconductive semiconductor device for photon microwave based on the different-surface structure electrode of the wide-bandgap photoconductive semiconductor wafer and the external electrode metallization connection and high-insulation packaging method thereof are provided, the electrode contact problem is solved through reasonable design, the contact impedance between the photoconductive semiconductor device and the external electrode is reduced, the loop connection inductance and high-voltage insulation are reduced, the practical application of the photoconductive semiconductor device in a photoconductive circuit in a picosecond time domain is realized, the photoconductive semiconductor device achieves megawatt power capacity, and the technical support is laid for high-power photoconductive microwave.

In order to achieve the purpose, the invention adopts the following technical scheme:

a megawatt photoconductive semiconductor device comprises an insulating packaging box 1, a positive electrode 2, a negative electrode 3, a second fixing plate 5 and a wide bandgap photoconductive semiconductor wafer 6. The insulating packaging box 1 is a hollow cube, a deep groove is formed in one side face of the cube, the positive electrode 2 and the negative electrode 3 are clamped in the deep groove through the groove formed in the upper surface and the lower surface of the left side of the L-shaped I, and then the positive electrode and the negative electrode are pressed and fixed by a second fixing plate 5 with a bulge in the middle; the positive electrode 2 and the negative electrode 3 are in a shape like a Chinese character 'ji', hollow cylindrical contact electrodes are arranged at the right end of the shape like a Chinese character 'ji', and the wide bandgap photoconductive semiconductor wafer 6 is compacted by the two hollow cylindrical contact electrodes and is in good electric contact; electrode pins are arranged at the lower end of the horizontal line and the vertical line so as to be convenient for connecting an external circuit; threaded holes are formed in the crossed positions of the Chinese character 'factory' shapes, and the compression degree between the two hollow cylindrical contact electrodes is adjusted through fastening screws penetrating through the threaded holes. And the hollow part of the cube is filled with insulating pouring sealant, so that the two contact electrodes and the wide bandgap photoconductive semiconductor wafer 6 are ensured to be immersed in the insulating pouring sealant, and the occurrence of electric breakdown is prevented.

Further, the invention also has a first fixing plate 4, and the positive electrode 2 can be fixed on the other side of the insulating packaging box through the first fixing plate 4 according to the circuit connection requirement.

Furthermore, the insulating packaging box 1, the first fixing plate 4, the second fixing plate 5 and the fastening screw are made of nylon or polytetrafluoroethylene, and the positive electrode 2 and the negative electrode 3 are made of brass.

Further, the wide bandgap optical semiconductor wafer 6 of the present invention is a SiC wide bandgap optical semiconductor wafer covered with a zinc oxide transparent electrode.

The invention also provides a method for connecting and insulating and packaging the external electrode of the photoconductive semiconductor device, which mainly comprises eight steps of electrode coating treatment, conductive silver colloid preparation, external electrode coating, ohmic contact between electrodes, ohmic contact metallization, insulating pouring sealant preparation, insulating pouring sealant defoaming treatment and insulating pouring sealant curing, and the specific implementation mode is as follows:

(S1) electrode application: firstly, carrying out air dust removal on an electrode-coated area (an area contacted with a positive electrode and a negative electrode) of the wide-bandgap photoconductive semiconductor wafer, and carrying out micro-wiping treatment on the electrode-coated area by using 4009A antistatic optical dust-free cloth and matching with acetone so as to clean the surface of the electrode-coated area and form good electric connection with an external metal electrode; finally, the wide bandgap photoconductive semiconductor wafer is placed in a dust-free vacuum drying oven for drying treatment;

(S2) conductive silver paste preparation: the type of the used conductive silver adhesive is EPO-TEK/H20E, and the conductive silver adhesive consists of two components A and B; a, B taking out the conductive silver colloid of the two components, weighing A, B with a precise electronic scale respectively to ensure the consistent weight, pouring A, B with consistent weight into a clean blending dish, and stirring fully and uniformly;

(S3) external electrode coating: uniformly coating the prepared conductive silver adhesive in the step S2 on the annular contact surfaces of the positive and negative electrode hollow cylindrical contact electrodes;

(S4) electrode ohmic contact: ensuring that the annular surface of the wide-bandgap photoconductive semiconductor wafer, which is coated with the electrodes, is coaxial with the annular surfaces of the positive electrode and the negative electrode, adjusting the fastening screw to fasten ohmic contact between the wide-bandgap photoconductive semiconductor wafer electrode and the hollow cylindrical contact electrodes of the positive electrode and the negative electrode, and adjusting the second fixing plate 5 to further reinforce the ohmic contact of the wide-bandgap photoconductive semiconductor wafer electrode;

(S5) ohmic contact metallization: putting the whole insulated packaging box assembled with the positive electrode, the negative electrode and the wide bandgap photoconductive semiconductor wafer into a vacuum drying box for drying; after the temperature in the drying oven is naturally cooled, injecting pure dry nitrogen into the vacuum drying oven, and taking out the nitrogen when the pressure is balanced with the room pressure;

(S6) preparing an insulating pouring sealant: the type of the used insulating pouring sealant is SYLGARD 184, the preparation ratio of the used main agent to the used auxiliary agent is 1:10, the main agent and the auxiliary agent are placed in a clean container vessel and are stirred uniformly until the main agent and the auxiliary agent are mixed fully;

(S7) defoaming the insulating pouring sealant: placing the uniformly mixed insulating pouring sealant in a vacuum box, performing vacuum air exhaust by using a vacuum pump, and taking out the insulating pouring sealant after all bubbles in the insulating pouring sealant are removed;

(S8) curing the insulating pouring sealant: pouring the defoamed insulating pouring sealant into the hollow part of the insulating packaging box, dipping the positive electrode, the negative electrode and the wide bandgap photoconductive semiconductor wafer into the insulating pouring sealant, then carrying out vacuum defoaming on the insulating packaging box poured with the insulating pouring sealant again, and then placing the insulating packaging box in a vacuum drying box for high-temperature curing; and after the temperature in the box is naturally cooled, taking out the box to obtain the final optical semiconductor packaging device.

The invention can achieve the following technical effects:

the invention takes the photoconductive semiconductor insulating packaging box as a main structure, and well solves the problems of ohmic contact and high-voltage insulation of a micron-sized photoconductive semiconductor device and an external electrode through electrode coating and insulating glue encapsulation. By optimizing the electrode structure and improving the measures of coating, encapsulating and the like, the ohmic contact problem of the photoconductive semiconductor device and an external circuit is solved, the ohmic contact impedance of the photoconductive semiconductor device is greatly reduced, and the stability of ohmic contact is ensured. The invention can effectively improve the voltage-resistant insulating property of the photoconductive semiconductor device and the overall compactness of the system under the conditions of dozens of ns pulse width and dozens of kV magnitude repetition frequency pulse high voltage, and realizes the output of megawatt magnitude photon microwave.

Drawings

Fig. 1 is a schematic structural diagram of an optical semiconductor package according to the present invention, wherein fig. (a) is a packaging diagram of the same side of an electrode, and fig. (b) is a packaging diagram of the opposite side of the electrode;

FIG. 2 is an exploded view of a photoconductive semiconductor package according to the present invention, wherein (a) is a packaging diagram of the same side of the electrodes and (b) is a packaging diagram of the opposite side of the electrodes;

FIG. 3(a) is a schematic structural view of the optical semiconductor insulating package 1 of the present invention, FIG. 3(b) is a front view of the structure, FIG. 3(c) is a cross-sectional view taken along AA ', and FIG. 3(d) is a cross-sectional view taken along BB';

FIG. 4(a) is a schematic structural view of the positive contact electrode 2 of the present invention, FIG. 4(b) is a front structural view, FIG. 4(c) is a cross-sectional view taken along AA', and FIG. 4(d) is a cross-sectional view taken along BB;

FIG. 5(a) is a schematic structural view of the negative contact electrode 3 of the present invention, FIG. 5(b) is a front structural view, FIG. 5(c) is a cross-sectional view taken along AA ', and FIG. 5(d) is a cross-sectional view taken along BB';

FIG. 6(a) is a schematic structural view of the first fixing plate structure 4 of the present invention, and FIG. 6(b) is a cross-sectional view taken along AA';

FIG. 7(a) is a schematic structural view of a second fixing plate structure 5 of the present invention, and FIG. 7(b) is a cross-sectional view taken along AA';

fig. 8 is an output waveform obtained in an experiment of the photoconductive semiconductor device according to the present invention.

Detailed Description

The following detailed description of embodiments of the invention is provided in connection with the accompanying drawings.

As shown in figure 1, the invention consists of an insulating packaging box 1, a positive electrode 2, a negative electrode 3, a first fixing plate 4, a second fixing plate 5 and a SiC wide bandgap photoconductive semiconductor wafer 6 covered with a zinc oxide transparent electrode. The insulating packaging box 1 is a hollow cube, a deep groove is formed in one side face of the cube, the positive electrode 2 and the negative electrode 3 are clamped in the deep groove through the groove formed in the upper surface and the lower surface of the left side of the L-shaped I, and then the positive electrode and the negative electrode are pressed and fixed by a second fixing plate 5 with a bulge in the middle; the positive electrode 2 and the negative electrode 3 are in a shape like a Chinese character 'ji', hollow cylindrical contact electrodes are arranged at the right end of the shape like a Chinese character 'ji', and the SiC wide bandgap photoconductive semiconductor wafer 6 is compacted by the two hollow cylindrical contact electrodes and is in good electric contact; two grooves are arranged on the upper and lower surfaces of the left side of the I, and electrode pins are arranged at the lower end of the L-shaped vertical lines for facilitating the fixed connection of circuits. Threaded holes are formed in the crossed positions of the Chinese character 'factory' shapes, and the compression degree between the two hollow cylindrical contact electrodes is adjusted through fastening screws penetrating through the threaded holes. And the hollow part of the cube is filled with insulating pouring sealant, so that the positive electrode, the negative electrode and the SiC wide bandgap photoconductive semiconductor wafer are immersed in the insulating pouring sealant, and the electric breakdown is prevented.

The insulating packaging box 1, the first fixing plate 4, the second fixing plate 5 and the fastening screw are made of nylon or polytetrafluoroethylene, and the positive electrode 2 and the negative electrode 3 are made of brass.

Fig. 3(a) is a schematic structural view of the photoconductive semiconductor insulating package 1 of the present invention. Wherein FIG. 3(b) is a structural elevation view; FIG. 3(c) is a cross-sectional view taken along AA'; FIG. 3(d) is a cross-sectional view taken along line DD'. The insulating packaging box 1 is of a hollow square platform structure and is of an axisymmetric structure along AA'. The height of the front end face is H₁Width of L₁The top end of the left end face has a length L₂The length of the base is L₃Height of H₂The radius of the top edge fillet is R₁The radius of the fillet of the edge at the rear side of the base is R₂. The bottom end of the hollow groove in the inner part is flush with the upper end surface of the base of the insulation packaging box 1, and the length of the front end surface is L₄Height of H₃The depth of the empty groove is L₅The radius of the round corners of the four edges of the empty nest on the positive end surface is R₃. The left and right end surfaces are respectively dug with fixed square grooves which penetrate along the left and right end surfaces and have a width L₅Satisfy the followingColumn relationship L₅＝(L₁-L₄) A height of H,/2₄The depth of the left end face is L₆Right end face depth of L₇. Four identical threaded holes are respectively distributed in axial symmetry with AA 'and DD' and have a distance L from AA₈And is at a distance L from DD₉The specification of the threaded hole is M phi₄Depth of L₁₀. Two through holes are dug at the rear side of the base, and the radius of each through hole is R₅And a distance L from the rear edge of the base₁₁At a distance L from the plane of symmetry AA₁₂。

Fig. 4(a) is a schematic view of the structure of the positive contact electrode 2 of the present invention. Wherein FIG. 4(b) is a front view of the structure, FIG. 4(c) is a cross-sectional view along AA', and FIG. 4(d) is a cross-sectional view along BB. The positive contact electrode 2 is mainly composed of a hollow cylindrical electrode 201, a fixing hole 202, a base 203, a fixing groove 204, a fixing beam 205, and a support beam 206. The hollow cylindrical electrode 201 is axially symmetrical along AA ', and the distance between the two ends of the electrode and the symmetrical plane of AA' is L₁₃. The electrode 201 has an outer diameter R₆Inner diameter of R₇Inner edge fillet radius of R₈The radius of the external edge fillet is R₉. The fixing hole 202 is connected with the hollow cylindrical electrode 201 through a fixing beam 205 structure, and the fixing beam 205 is externally connected with the hollow cylindrical electrode 201. Width L of fixed beam 205₁₄Thickness of L₁₅The distance between BB' surface and the edge of the support beam 206 is L₁₆. The radius of the fillet of the outer edge of the connection between the fixed beam 205 and the support beam 206 is R₁₀The radius of the inner edge fillet is R₁₁. The width of the fixing groove 204 is L₁₇A distance L from the left edge of the support beam₁₈Radius R₁₂. The base 203 and the fixing hole 202 are connected by a support beam 206 structure, and the support beam 206 has a width L₁₉The distance between the upper edge of the base 203 and the fixed beam 205 is L₂₀The height of the base 203 is L₂₁Length of L₂₂Width of L₂₃. The radius of the fillet of three vertical edges of the base except the supporting beam is R₁₃. The distance between the section CC 'and the section BB' is L₂₄. A through threaded hole is dug on the base 203, the threaded hole is symmetrical about the CC' section axis, and the distance from the front end surface of the base is L₂₅Screw threadThe specification of the grain hole is M phi₁₄The radius of the upper edge fillet is R₁₅. The fixing groove 204 is located on the fixing beam 205 and is used for connecting and fixing the insulating packaging box 1 and the positive contact electrode 2. The distance between the right side of the fixing groove 204 and the BB' section is L₂₆。

Fig. 5(a) is a schematic view of the structure of the negative contact electrode 3 of the present invention. Wherein FIG. 5(b) is a front view of the structure, FIG. 5(c) is a cross-sectional view along AA ', and FIG. 5(d) is a cross-sectional view along BB'. The negative contact electrode 3 is mainly composed of a hollow cylindrical electrode 301, a threaded fixing hole 302, a base 303, a fixing groove 304, a fixing beam 305 and a support beam 306. The hollow cylindrical electrode 301 structure is axisymmetric along AA ', and the distance between the electrode end and the symmetry plane of AA' is L₁₃₁. Electrode 301 has an outer diameter R₆₁Inner diameter of R₇₁The radius of the inner edge fillet is R₈₁The radius of the external edge fillet is R₉₁. The fixing hole 302 is connected with the hollow cylindrical electrode 301 through a fixing beam 305 structure, and the fixing beam 305 is externally tangent with the hollow cylindrical electrode 301. Width L of fixed beam 305₁₄₁Thickness of L_151,The distance between BB' surface and the edge of the support beam 306 is L₁₆₁. The radius of the round corner of the outer edge connecting the fixed beam 305 and the support beam 306 is R₁₀₁The radius of the inner edge fillet is R₁₁₁. The groove 304 has a length L₁₇₁A distance L from the left edge of the support beam₁₈₁The specification of the thread hole is M phi₁₂₁. The base 303 and the fixing hole 302 are connected by a support beam 306 structure, and the support beam 306 has a width L₁₉₁The distance between the upper edges of the base 303 and the fixed beam 305 is L₂₀₁The height of the base 303 is L₂₁₁Length of L₂₂₁Width of L₂₃₁. The radius of the fillet of three vertical edges of the base except the supporting beam is R₁₃₁. The distance between the section CC 'and the section BB' is L₂₄₁. A through threaded hole is dug on the base 303, the threaded hole is symmetrical about the CC' section axis, and the distance from the front end surface of the base is L₂₅₁The specification of the threaded hole is M phi₁₄₁The radius of the upper edge fillet is R₁₅₁. The fixing groove 304 is located on the fixing beam 305, and is used for connecting and fixing the insulating packaging box 1 and the negative contact electrode 3. The distance between the right side of the fixed groove 304 and the BB' section is L₂₆₁。

Fig. 6(a) is a schematic structural view of the first fixing plate structure 4 of the present invention. Wherein FIG. 6(b) is a top view of the structure. The first fixing plate 4 has an axisymmetric structure along AA ', BB'. The length of the bottom edge of the front end surface of the first fixing plate 4 is L₂₈Width of L₂₉Height of H₆The length of the protruding part is L₃₀Height of H₇. Two through holes are symmetrical about BB ', and the distance from the symmetry plane of BB' is L₃₁Radius of the through hole is R₁₆。

Fig. 7(a) is a schematic structural view of a second fixing plate structure 5 of the present invention. Wherein FIG. 7(b) is a top view of the structure. The second fixing plate 5 has an axisymmetric structure along AA ', BB'. The length of the bottom edge of the front end surface of the second fixing plate 4 is L₂₈₁Width of L₂₉₁Height of H₆₁The length of the protruding part is L₃₀₁Height of H₇₁. Two through holes are symmetrical about BB ', and the distance from the symmetry plane of BB' is L₃₁₁Radius of the through hole is R₁₆₁。

The national defense science and technology university prepares a photoconductive semiconductor wafer based on the SiC wide bandgap according to the structure of the invention, and realizes the electrode optimized connection and the insulation packaging of the megawatt-level photon microwave photoconductive system. The response sizes of the implementation examples are: r₁＝3.0mm， R₂＝3.0mm，R₃＝2.0mm，R₄＝3.0mm，R₅＝5.5mm，R₆＝2.5mm，R₇＝3.5mm，R₈＝0.2mm，R₉＝0.7mm， R₁₀＝3.0mm，R₁₁＝1.0mm，R₁₂＝1.6mm，R₁₃＝2.0mm，R₁₅＝2.0mm，Φ₁₄＝4.0mm，R₆₁＝2.5mm， R₇₁＝3.5mm，R₈₁＝0.2mm，R₉₁＝0.7mm，R₁₀₁＝3.0mm，R₁₁₁＝1.0mm，Φ₁₂₁＝3.2mm，R₁₃₁＝2.0mm， R₁₅₁＝2.0mm，Φ₁₄₁＝4.0mm，R₁₆＝1.75mm，R₁₆₁＝1.75mm，L₁＝30.0mm，L₂＝27.0mm，L₃＝42.0mm， L₄＝20.0mm，L₅＝22.0mm，L₆＝17.0mm，L₇＝2.3mm，L₈＝12.5mm，L₉＝5.0mm，L₁₀＝8.0mm， L₁₁＝7.5mm，L₁₂＝7.5mm，L₁₃＝3.5mm，L₁₄＝3.0mm，L₁₅＝5.0mm，L₁₆＝20.0mm，L₁₇＝5.0mm， L₁₈＝2.5mm，L₁₉＝3.0mm，L₂₀＝18.5mm，L₂₁＝3.0mm，L₂₂＝8.0mm，L₂₃＝9.0mm，L₂₄＝21.0mm， L₂₅＝2.5mm，L₂₆＝10.0mm，L₁₃₁＝3.5mm，L₁₄₁＝3.0mm，L₁₅₁＝5.0mm，L₁₆₁＝20.0mm，L₁₇₁＝5.0mm， L₁₈₁＝2.5mm，L₁₉₁＝3.0mm，L₂₀₁＝18.5mm，L₂₁₁＝3.0mm，L₂₂₁＝8.0mm，L₂₃₁＝9.0mm，L₂₄₁＝21.0mm， L₂₅₁＝2.5mm，L₂₆₁＝10.0mm，L₂₈＝20.0mm，L₂₉＝5.0mm，L₃₀＝5.0mm，L₃₁＝5.0mm，L₂₈₁＝20.0mm， L₂₉₁＝5.0mm，L₃₀₁＝5.0mm，L₃₁₁＝5.0mm，H₁＝30.0mm，H₂＝5.0mm，H₃＝20.0mm，H₄＝5.0mm，H₆＝3.0mm，H₇＝5.3mm，H₆₁＝3.0mm，H₇＝7.0mm。

Fig. 8 is an output waveform obtained in an experiment using the photoconductive semiconductor device obtained by the present patent. By designing an external electrode structure and insulating packaging, megawatt-level photon microwave repetition frequency output of high voltage 18kV and high power 10.65MW can be realized under the condition that the triggering light energy is about 25 mJ.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention.