CN113809200A - Laser drilling three-dimensional spherical electrode detector, design method and application - Google Patents
Laser drilling three-dimensional spherical electrode detector, design method and application Download PDFInfo
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- 238000005553 drilling Methods 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 title claims abstract description 23
- 238000013461 design Methods 0.000 title claims abstract description 18
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 41
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- 239000010703 silicon Substances 0.000 claims abstract description 41
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- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 19
- 229910052782 aluminium Inorganic materials 0.000 claims description 19
- 238000005530 etching Methods 0.000 claims description 16
- 239000000523 sample Substances 0.000 claims description 5
- 238000004080 punching Methods 0.000 claims description 3
- 230000007123 defense Effects 0.000 claims description 2
- 238000009206 nuclear medicine Methods 0.000 claims description 2
- 230000005684 electric field Effects 0.000 abstract description 20
- 239000004065 semiconductor Substances 0.000 abstract description 6
- 125000000623 heterocyclic group Chemical group 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 11
- 238000004088 simulation Methods 0.000 description 11
- 230000007547 defect Effects 0.000 description 8
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- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
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Abstract
The invention belongs to the technical field of semiconductor detectors, and discloses a laser drilling three-dimensional spherical electrode detector, a design method and application. The middle of the upper end of the N-type lightly doped silicon substrate is doped with an N-type heavily doped anode, and the outer side of the N-type heavily doped anode is doped with a plurality of P-type heavily doped upper surface rings which are arranged at equal intervals; the bottom of the N-type lightly doped silicon substrate is provided with a P-type heavily doped cathode, and the P-type heavily doped cathode is provided with a P-type heavily doped ring and a P-type heavily doped surface. The distances between the anode and the cathode are the same, so that the potential distribution in the detector is very uniform, and the charge collection rate of the novel detector unit is improved; the electric field distribution on the inner surface of the detector unit is more uniform due to the design of heavily doped heterocycle on the upper surface; according to the prior art, the spherical electrode can be realized by uniformly drilling holes by a laser and doping by ion diffusion.
Description
Technical Field
The invention belongs to the technical field of semiconductor detectors, and particularly relates to a laser drilling three-dimensional spherical electrode detector, a design method and application.
Background
At present, with the progress of society and the development of science and technology, the application of semiconductor materials has become an indispensable part of life, and detectors based on semiconductor materials are also produced. The traditional detector process is gradually improved, and in a large number of semiconductor detectors, silicon detectors are widely applied to the fields of aerospace, celestial body physics, high-energy physics, nuclear medicine, national defense and the like due to the superior performance and mature and advanced process technology of the silicon detectors.
Common types of silicon detectors include: the device comprises a silicon micro-strip detector, a silicon strip pixel detector, a silicon drift chamber detector, a three-dimensional columnar electrode detector, a three-dimensional groove electrode silicon detector and the like. With the evolution and development of various semiconductor detectors, the structure and performance of the detector are gradually improved and perfected from two dimensions to three dimensions.
The silicon detector works under reverse bias, when photons or other high-energy particles with certain energy are incident into a sensitive region of the detector, the energy is transferred to silicon-based atoms, electrons in the silicon-based atoms are transited from a valence band to a conduction band to form electron-hole pairs, the electrons drift to an anode and the holes drift to a cathode under the action of an internal and external electric field, and the electrons and the holes are collected and processed by corresponding electrodes respectively, and meanwhile, an electric signal generated by detector equipment is read by external electronic equipment.
Any three-dimensional type silicon detector device structure has the defect that the structure cannot be avoided, for example, the traditional three-dimensional groove electrode silicon detector can not completely penetrate through the whole silicon substrate because the etching substrate is required to be ensured not to fall off, and the groove electrode can only be etched to the depth of about 90% of the silicon substrate, so that compared with a laser drilling three-dimensional spherical electrode detector with the same size, the first defect of the traditional three-dimensional groove electrode silicon detector is that a dead zone exists and the proportion is overlarge. Dead zones are areas of weak or zero electric field. If the dead zone is large in the proportion of the detector substrate, it may result in poor electrical characteristics of the detector, such as uneven distribution of electric potential or electric field, and charge collection efficiency may also be affected. When the three-dimensional groove detector is processed and manufactured, due to process technical reasons, the base body cannot be completely etched to the bottom, namely, a certain thickness is reserved on the detector base body to be used as a substrate, so that the mechanical stability of a detector structural unit or an array is stabilized, and the base body is prevented from falling off due to etching. The substrate is a weak or zero electric field region, which cannot work normally when the detector device works, so that the substrate forms a dead region.
Secondly, in the conventional three-dimensional trench electrode detector, the electrode spacing is different, which is also an important reason for the reduction of the charge collection rate. The position and angle of incidence of heavy ions are different, and the charge collection rate is also different. The electric field is lowest, as incident from the position of maximum electrode spacing, and therefore has the greatest charge trapping effect on the drifting electron-hole, so that the charge collection rate is lowest here. The charge collection rate is highest if incident at the position where the electrode spacing is smallest. The difference in electrode spacing has a large effect on the stability of the detector performance.
Aiming at the defects of the traditional three-dimensional groove detector, a novel semispherical shell type electrode silicon detector is proposed in recent years, and the structural model of the detector can really solve the defects of uneven electric field potential distribution, overlarge dead zone and the like of the traditional three-dimensional groove detector. As a detector unit, the structural performance of the spherical detector is very outstanding and can be realized in theoretical simulation, but the ideal spherical structure is relatively difficult in process manufacturing.
The laser drilling three-dimensional spherical electrode detector can utilize the prior process technology to uniformly drill a laser for multiple times to form a groove, and the groove is doped by an ion diffusion method to finally form the spherical electrode. The distance between the anode and the cathode is the same, and a plurality of heavily doped rings with equal intervals are added on the upper surface, so that the electric field potential distribution is more uniform, and the dead zone is reduced.
Through the above analysis, the problems and defects of the prior art are as follows:
the performance of the existing silicon detector is low, and the ideal spherical structure is relatively difficult in process manufacturing.
The difficulty in solving the above problems and defects is:
the traditional three-dimensional groove electrode detector has the defects which cannot be avoided, and the ideal spherical detector is extremely difficult to manufacture in the process.
The significance of solving the problems and the defects is as follows:
as a detector unit, the spherical detector has outstanding structural performance, and the spherical electrode design can be realized by using the existing technologies such as laser etching, ion diffusion and the like through ingenious structural design, so that the spherical electrode design is not only existed in theoretical simulation. And the heavily doped ring is added on the upper surface, so that the electric field is more uniform, and the dead zone is reduced. These techniques all lead to a significant improvement in the performance of silicon detectors.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a laser drilling three-dimensional spherical electrode detector, a design method and application.
The invention is realized in this way, a design method of a laser drilling three-dimensional spherical electrode detector, comprising:
and uniformly punching a hole for multiple times by using a laser to form a groove, and doping in the groove by using an ion diffusion method to finally form the spherical electrode.
The structural size and the internal configuration are calculated by formulas. The formula is as follows:
Given d＝R,pitch P,gap g＝βP
xi＝iP(i＝1,2,....N)
yN＝ξR(ξtakes a value of 0.9)
d＝R,xN＝R,yN＝ξR,(0<ξ<1),P,W,g
xi＝iP(i＝1,....,N)
wherein R is 200 μm, β is 0.8, P is 20 μm, W is 16, xiRepresents the distance from the center coordinate of the etching column to the origin, yiRepresents the height of the etched pillar, i represents the number of etched pillars, N represents the number, y10＝0.9*R。
The radius of the upper surface N-type collecting anode is 17.5 mu m, and the radius of the anode aluminum electrode contact layer is 17.5 mu m. The distance between the inner circle and the outer circle of all heavily doped rings on the upper surface is 17.5 mu m, and the distance between each two rings is 3.5 mu m.
The substrate of the invention has ten etching rings (the cross section of the X axis is an etching column), the column width is 16 μm, and the column spacing is 4 μm. From inside to outside, the central abscissa and ordinate of each etching column are respectively:
x1＝20μm，y1＝1.0025μm；x2＝40μm，y2＝4.04μm；x3＝60μm，y3＝9.212μm；x4＝80μm，y4＝16.6969μm；x5＝100μm，y5＝26.7949μm；x6＝120μm，y6＝40.00μm；x7＝140μm，y7＝57.1714μm；x8＝160μm，y8＝80μm；x9＝180μm，y9＝112.822μm；x10＝200μm，y10＝180μm。
the radius of the cathode aluminum electrode contact layer on the lower surface is 200 μm.
Furthermore, in the spherical electrode, the distances between the anode and the cathode are the same, so that the potential distribution in the spherical electrode is uniform. As shown in fig. 14.
Another object of the present invention is to provide a laser drilling three-dimensional spherical electrode probe provided with:
n-type lightly doped silicon substrate;
the middle of the upper end of the N-type lightly doped silicon substrate is doped with an N-type heavily doped anode, and the outer side of the N-type heavily doped anode is doped with a plurality of P-type heavily doped upper surface rings which are arranged at equal intervals;
and a P-type heavily doped cathode is arranged at the bottom of the N-type lightly doped silicon substrate.
Furthermore, the P-type heavily doped cathode is provided with a P-type heavily doped ring and a P-type heavily doped surface, the P-type heavily doped ring is provided with a plurality of heavily doped rings which are arranged at equal intervals, and the P-type heavily doped surface is positioned at the bottom of the P-type heavily doped ring.
Furthermore, the doping depth of the plurality of P-type heavily doped rings in the N-type lightly doped silicon matrix is gradually increased from the middle to the outside.
Furthermore, the upper end of the N-type heavily doped anode and the lower end of the P-type heavily doped cathode are respectively connected with an anode aluminum electrode contact layer and a cathode aluminum electrode contact layer.
Furthermore, the upper end of the N-type lightly doped silicon substrate is covered with SiO on the upper surface outside the anode aluminum electrode contact layer2A layer, wherein the lower end of the N-type lightly doped silicon substrate is covered with a lower surface SiO on the outer side of the cathode aluminum electrode contact layer2And (3) a layer.
By combining all the technical schemes, the invention has the advantages and positive effects that:
the detector in the invention is designed in a spherical shape, and the distances from the anode to the cathode are the same, so that the potential distribution in the detector is very uniform (as shown in figure 14), and the charge collection rate of the novel detector unit is improved.
The design of heavily doped rings on the upper surface of the detector unit enables the electric field distribution on the inner surface of the detector unit to be more uniform.
According to the prior art, the spherical electrode can be realized by uniformly drilling holes through a laser and doping by ion diffusion.
The invention has small full depletion voltage and lower energy consumption, the full depletion voltage is 23V under the non-irradiation condition, the full depletion voltage is lower than that of the traditional three-dimensional groove detector with the same size, and the leakage current and the capacitance are smaller.
The existence of the whole surface electrode on the lower surface in the invention makes the whole surface electrode easier to be arranged in an array and greatly reduces the dead zone.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained from the drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a laser drilling three-dimensional spherical electrode detector provided by an embodiment of the invention.
Fig. 2 is a cross-sectional view of a laser drilled three-dimensional spherical electrode probe provided by an embodiment of the invention.
Fig. 3 is a schematic structural diagram of an anode aluminum electrode contact layer provided in an embodiment of the present invention.
Fig. 4 is a schematic view of a P-type heavily doped ring structure according to an embodiment of the present invention.
Fig. 5 is a schematic structural diagram of a cathode aluminum electrode contact layer provided in an embodiment of the invention.
In the figure: 1. an anodic aluminum electrode contact layer; 2. an N-type heavily doped anode; 3. a P-type heavily doped upper surface ring; 4. SiO on the upper surface2A layer; 5. n-type lightly doped silicon substrate; 6. a P-type heavily doped heterocycle; 7. a P-type heavily doped surface; 6 and 7 form a P-type heavily doped cathode; 8. a cathode aluminum electrode contact layer; 9. SiO on the lower surface2And (3) a layer.
Fig. 6 is a graph of electron concentration provided by an embodiment of the present invention.
Fig. 7 is a partially enlarged view of an electron concentration profile provided by an embodiment of the present invention.
Fig. 8 is a simulation diagram of the electric field distribution provided by the embodiment of the invention.
FIG. 9 is a simulation diagram of electric field distribution of a conventional three-dimensional trench detector of the same size according to an embodiment of the present invention.
Fig. 10 is a diagram of a potential distribution simulation provided by an embodiment of the present invention.
Fig. 11 is a graph showing a simulation of the potential distribution of a conventional three-dimensional trench detector with the same size according to an embodiment of the present invention.
Fig. 12 is a graph of leakage current provided by an embodiment of the present invention.
Fig. 13 is a comparison graph of leakage current magnitude of the conventional three-dimensional trench detector of the same size according to the present invention.
Fig. 14 is a diagram of the same distance between the anode and the cathode in the spherical electrode provided by the embodiment of the present invention, so that the potential distribution in the spherical electrode is uniform.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Aiming at the problems in the prior art, the invention provides a laser drilling three-dimensional spherical electrode detector, which is described in detail below with reference to the accompanying drawings.
The invention provides a design method of a laser drilling three-dimensional spherical electrode detector, which comprises the following steps:
and uniformly punching a hole for multiple times by using a laser to form a groove, and doping in the groove by using an ion diffusion method to finally form the spherical electrode.
In the spherical electrode, the distances from the anode to the cathode are the same, so that the potential distribution in the spherical electrode is uniform.
As shown in fig. 1 to 5, the laser drilling three-dimensional spherical electrode detector provided by the embodiment of the invention is provided with a 400 μm 200 μm cubic column N-type lightly doped silicon substrate 5, wherein the N-type lightly doped silicon substrate 5 is N-type lightly doped with a doping concentration of 1 × 1012/cm3The top layer of the N-type lightly doped silicon substrate 5 is an anode aluminum electrode contact layer 1 covering the N-type heavily doped anode 2 and used as a central anode signal output point.
The upper surface of the N-type lightly doped silicon substrate 5 is provided with eight P-type heavily doped upper surface rings 3 and a central heavily doped anode, and the doping concentration of each doping ring is 1 multiplied by 1018/cm3Is heavily doped in P type with a doping depth of 1 μm and an anode with a doping concentration of 1 × 1018/cm3The doping depth of the N-type heavy doping is 1 mu m.
The cathode consists of ten etching rings (the X-axis section is an etching column) and a heavily doped lower surface, the etching rings form a P-type heavily doped ring by an ion diffusion method, and the doping concentration is 1 multiplied by 1019/cm3The lower surface has a doping concentration of 1 × 1018/cm3The doping depth of the P-type heavily doped surface is 1 mu m, and the P-type heavily doped surface plays a role in connecting the etching rings, so that the cathode is integrated. The bottom is a cathode aluminum electrode contact layer 8 covering the heavily doped lower surface as a cathode voltage input point.
The laser drilling three-dimensional spherical electrode detector in the embodiment of the invention has the top layer and the bottom part which are not provided with the electrode contact layer covered with SiO2And (3) a layer. The contact layers of the aluminum electrodes on the upper and lower surfaces have the thickness of 1 mu m, and the SiO layer on the upper surface2Layer 4 and lower surface SiO2The layers 9 are each 0.5 μm thick.
In a preferred embodiment of the invention, the structural dimensions and internal configuration are calculated by formulas. The formula is as follows:
Given d＝R,pitch P,gap g＝βP
xi＝iP(i＝1,2,....N)
yN＝ξR(ξtakes a value of 0.9)
d＝R,xN＝R,yN＝ξR,(0<ξ<1),P,W,g
xi＝iP(i＝1,....,N)
wherein R is 200 μm, β is 0.8, P is 20 μm, W is 16, xiRepresents the distance from the center coordinate of the etching column to the origin, yiRepresents the height of the etched pillar, i represents the number of etched pillars, N represents the number, y10＝0.9*R。
The radius of the upper surface N-type collecting anode is 17.5 mu m, and the radius of the anode aluminum electrode contact layer is 17.5 mu m. The distance between the inner circle and the outer circle of all heavily doped rings on the upper surface is 17.5 mu m, and the distance between each two rings is 3.5 mu m.
The substrate of the invention has ten etching rings (the cross section of the X axis is an etching column), the column width is 16 μm, and the column spacing is 4 μm. From inside to outside, the central abscissa and ordinate of each etching column are respectively:
x1＝20μm，y1＝1.0025μm；x2＝40μm，y2＝4.04μm；x3＝60μm，y3＝9.212μm；x4＝80μm，y4＝16.6969μm；x5＝100μm，y5＝26.7949μm；x6＝120μm，y6＝40.00μm；x7＝140μm，y7＝57.1714μm；x8＝160μm，y8＝80μm；x9＝180μm，y9＝112.822μm；x10＝200μm，y10＝180μm。
the radius of the cathode aluminum electrode contact layer on the lower surface is 200 μm.
The working principle of the invention is as follows:
according to the laser drilling three-dimensional spherical electrode detector provided by the embodiment of the invention, the grooves can be formed by uniformly drilling for multiple times through a laser by utilizing the existing process technology, and the spherical electrodes are finally formed by doping in the grooves by an ion diffusion method. The basic principle of the three-dimensional spherical electrode detector is a PN junction or a PIN junction, which is the same as the principle of many other types of detectors. According to the laser drilling three-dimensional spherical electrode detector provided by the embodiment of the invention, a PN junction is formed between the etching column and the silicon substrate, an external electric field is formed by applying a reverse bias voltage, electrons in the external electric field drift towards an anode, holes drift towards a cathode, and the electrons are collected by a central anode on the upper surface of the detector, so that the potential at the position is highest. And then the feedback current signal is processed by an external integrated circuit, so that information such as energy, position, motion track and the like of incident particles can be obtained.
In the research field of the silicon detector at present, the influence of parameters such as depletion voltage, capacitance, leakage current, potential, electric field, charge collection and the like on the energy resolution, collection efficiency, noise and energy consumption of the silicon detector is generally used as an index for evaluating whether the performance of the detector is superior or not.
By comparing the characteristics of the traditional three-dimensional groove detector with the same size in the aspect of electrical characteristics, such as leakage current, depletion voltage, electric field potential distribution and the like. The advantages of the laser drilling three-dimensional spherical electrode detector in structure and performance are illustrated. The reason for the formation of the leakage current is due to the surface effect of the PN junction; the device shows that the particle charges cause mirror charges to be generated inside the device, so that the PN junction generates surface induction to form a surface depletion region, the depletion region is changed, and surface leakage current is generated. Therefore, the smaller the leakage current, the smaller the influence on the depletion region, the smaller the noise of the detector, and the higher the energy resolution. By contrast, the leakage current of the laser drilling three-dimensional spherical electrode detector is three orders of magnitude smaller than that of a three-dimensional groove detector with the same size. In addition, the electric field distribution of the detector is uniform, the electric potential distribution symmetry is high, and the property of the detector is more stable. The electron drift trajectory will be more pronounced and the energy resolution and collection efficiency will be better. By contrast, the laser-drilled three-dimensional spherical electrode detector is superior to the three-dimensional groove detector with the same size and has smaller depletion voltage. The presence of the full-area electrodes on the lower surface of the detector allows sufficient space for the application of bias voltages and allows easier array and greatly reduced dead space.
The technical solution of the present invention is further described below with reference to simulation experiments.
Fig. 6 is a graph of electron concentration provided by an embodiment of the present invention. Fig. 7 is a partial enlarged view of an electron concentration profile provided by an embodiment of the present invention, with the electron concentration continuing to decrease (the depletion region of the detector continuing to expand) as the bias voltage increases from 0V to 33V until full depletion is reached. It can be seen that the electron concentration of the depletion region has begun to be 1X 10 lower than that of the silicon substrate when the voltage reaches 23V12/cm3Therefore, we judge the depletion voltage value to be 23V.
Fig. 8 is a simulation diagram of the electric field distribution provided by the embodiment of the invention.
Fig. 9 is a simulation diagram of the electric field distribution of the conventional three-dimensional trench detector with the same size, and it is obvious that the electric field distribution of the three-dimensional trench detector is more uniform than that of the conventional three-dimensional trench detector.
Fig. 10 is a simulation diagram of the potential distribution of the present invention.
Fig. 11 is a simulation diagram of potential distribution of a conventional three-dimensional trench detector with the same size, which clearly shows that the potential distribution of the three-dimensional trench detector is more symmetrical than that of the conventional three-dimensional trench detector.
Fig. 12 is a graph of leakage current provided by an embodiment of the present invention.
Fig. 13 is a comparison graph of leakage current magnitude of the conventional three-dimensional trench detector of the same size according to the present invention. It can be clearly seen that the leakage current of the invention is much smaller than that of the conventional three-dimensional trench detector.
In a preferred embodiment of the present invention, as shown in fig. 14, the distance between the anode and the cathode is the same in the spherical electrode, so that the potential distribution in the spherical electrode is uniform.
In the description of the present invention, "a plurality" means two or more unless otherwise specified; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The above description is only for the purpose of illustrating the present invention and the appended claims are not to be construed as limiting the scope of the invention, which is intended to cover all modifications, equivalents and improvements that are within the spirit and scope of the invention as defined by the appended claims.
Claims (10)
1. A design method of a laser drilling three-dimensional spherical electrode detector is characterized by comprising the following steps:
and uniformly punching a hole for multiple times by using a laser to form a groove, and doping in the groove by using an ion diffusion method to finally form the spherical electrode.
2. The design method of the laser drilling three-dimensional spherical electrode detector as claimed in claim 1, wherein the distances between the anode and the cathode of the spherical electrode are the same, so that the potential distribution in the spherical electrode is uniform.
3. The method of claim 1, wherein the method further comprises designing the structural size and internal structure, and the method is calculated by the following formula:
Given d＝R,pitch P,gap g＝βP
xi＝iP(i＝1,2,....N)
yN＝ξR(ξtakes a value of 0.9)
d＝R,xN＝R,yN＝ξR,(0<ξ<1),P,W,g
xi＝iP(i＝1,....,N)
wherein R is 200 μm, β is 0.8, P is 20 μm, W is 16, xiRepresents the distance from the center coordinate of the etching column to the origin, yiRepresents the height of the etched pillar, i represents the number of etched pillars, N represents the number, y10＝0.9*R；
4. A laser-drilled three-dimensional spherical electrode detector is characterized in that the laser-drilled three-dimensional spherical electrode detector is provided with:
n-type lightly doped silicon substrate;
the middle of the upper end of the N-type lightly doped silicon substrate is doped with an N-type heavily doped anode, and the outer side of the N-type heavily doped anode is doped with a plurality of P-type heavily doped upper surface rings which are arranged at equal intervals;
and a P-type heavily doped cathode is arranged at the bottom of the N-type lightly doped silicon substrate.
5. The laser-drilled three-dimensional spherical electrode detector as claimed in claim 4, wherein the P-type heavily doped cathode is provided with a P-type heavily doped ring and a P-type heavily doped face, the P-type heavily doped ring is provided with a plurality of rings arranged at equal intervals, and the P-type heavily doped face is positioned at the bottom of the P-type heavily doped ring.
6. The laser drilled three-dimensional ball electrode probe of claim 5, wherein the doping depth of the plurality of P-type heavily doped rings in the N-type lightly doped silicon substrate gradually increases from the center to the outside.
7. The laser drilling three-dimensional spherical electrode detector as claimed in claim 4, wherein the upper end of the N-type heavily doped anode and the lower end of the P-type heavily doped cathode are respectively connected with an anode aluminum electrode contact layer and a cathode aluminum electrode contact layer.
8. The laser drilled three-dimensional spherical electrode probe as claimed in claim 7, wherein the upper end of the N-type lightly doped silicon substrate is covered with SiO on the upper surface outside the anode aluminum electrode contact layer2A layer, wherein the lower end of the N-type lightly doped silicon substrate is covered with a lower surface SiO on the outer side of the cathode aluminum electrode contact layer2And (3) a layer.
9. Use of a design method according to any one of claims 1 to 3 in the design of an aerospace probe.
10. The application of the design method as claimed in any one of claims 1 to 3 in the design of detectors in the fields of celestial physics, high-energy physics, nuclear medicine and national defense.
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