Three-dimensional trench electrode detector array and method of making same

Abstract

The application belongs to the technical field of three-dimensional detector, and particularly relates to a three-dimensional groove electrode detector array and a preparation method thereof. By reducing the area of each detection unit of the array at the junction and further reducing the etching depth at the junction, the three-dimensional groove electrode detector array bottom non-horizontal distribution state is effectively improved. It is favorable to improve the device bottom electric field distribution uniformity and further improve the collection of electrical signals. Therefore, the detector array designed in the application has a good application prospect in the fields of aerospace, deep space exploration, cosmic exploration, major physical experiments, medicine, X-ray imaging, military industry and the like.

Description

Technical Field

[0001] This application belongs to the field of three-dimensional detector technology, specifically relating to a three-dimensional trench electrode detector array and its fabrication method. Background Technology

[0002] Silicon detectors operate under reverse bias. When an external particle enters the detector's sensitive region, the resulting electron-hole pairs are separated under the reverse bias. Electrons move towards the positive electrode and are collected there, while holes move towards the negative electrode and are collected there. This process generates an electrical signal reflecting the particle's information in the external circuitry. Silicon detectors possess high detection sensitivity, fast response speed, strong radiation resistance, and are easy to integrate. They have significant application value in high-energy particle detection and X-ray detection, and show promising application prospects in high-energy physics and astrophysics.

[0003] The three-dimensional trench electrode silicon detector uses deep silicon etching technology to etch deep trenches in the silicon body, and then uses in-situ doping or ion implantation to form trench electrodes in the deep trenches. Compared with the traditional three-dimensional columnar electrode silicon detector, the saddle region (low electric field dead zone) between the same type of columnar electrodes disappears, the electric field distribution is more uniform, and because the trench electrode completely surrounds the central readout electrode, the crosstalk between adjacent pixel units is extremely low.

[0004] However, for a detector array composed of multiple three-dimensional trench electrode detection units, the etching depth at the junction formed by the detection units in the array is usually greater than that at other adjacent locations. This can easily lead to uneven electric field distribution at the bottom of the device, thus affecting the collection of electrical signals. Summary of the Invention

[0005] The technical objective of this application is to at least solve the problem that the relatively large etching depth at the junction of existing arrays composed of three-dimensional trench electrode detection units can easily cause uneven electric field distribution at the bottom of the device.

[0006] This objective is achieved through the following technical solutions:

[0007] In a first aspect, this application provides a three-dimensional trench electrode detector array, the array comprising detector units; each detector unit comprising:

[0008] Central electrode;

[0009] Trench electrode: includes a first trench wall and a second trench wall, wherein the first trench wall and the second trench wall are intersecting and form an intersection at the intersection;

[0010] The intersection has a width along a first direction and / or a second direction, the first trench wall has a width along the first direction, and the second trench wall has a width along the second direction;

[0011] Each width satisfies one or two of the following:

[0012] Along the first direction, the width of the intersection is not greater than the width of the first trench wall;

[0013] Along the second direction, the width of the intersection is not greater than the width of the second trench wall;

[0014] The first direction is different from the second direction.

[0015] This application selects that the width of the cross-position along the first and / or second directions is no greater than the width of the first trench wall and / or the width of the second trench wall. By reducing the area of ​​each detection unit at the interface of the array, and thus reducing its etching depth, the non-horizontal distribution state at the bottom of the three-dimensional trench electrode detector array is effectively improved. This is beneficial for improving the uniformity of the electric field distribution at the bottom of the device, thereby improving the collection of electrical signals. In addition, by increasing the breakdown voltage of the detector device, the probability of premature device breakdown caused by electric field concentration is reduced.

[0016] In some embodiments of this application, the first trench wall and / or the second trench wall have a first side end disposed near the intersection and a second side end disposed away from the intersection;

[0017] The gradient increases as the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction extends from the first side end to the second side end.

[0018] In this design, the trench wall width is greater than the cross-position width, which helps to reduce the area of ​​each detection unit in the array at the interface.

[0019] In some embodiments of this application, the first trench wall and / or the second trench wall have a first side end disposed near the intersection and a second side end disposed away from the intersection;

[0020] When the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction extend from the first end to the second side end, the gradient first increases and then decreases.

[0021] In this design, the width of the trench wall is greater than or equal to the width of the cross position, which helps to reduce the area of ​​each detection unit in the array at the interface.

[0022] In some embodiments of this application, the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction vary linearly and / or non-linearly as they extend from the first side end to the second side end.

[0023] Preferably, the nonlinear change includes exponential or logarithmic changes.

[0024] In this design, the width of the trench wall is selected to satisfy the above-mentioned gradient change law, which can also reduce the area of ​​each detection unit of the array at the junction.

[0025] In some embodiments of this application, the detection units are formed on both sides of the first trench wall and both sides of the second trench wall, and the detection units form an M×N detector array, where M and N are both positive integers.

[0026] In some embodiments of this application, the intersection position is provided with a through hole;

[0027] Preferably, the central axis of the through hole is aligned with the axial direction of the trench electrode;

[0028] Preferably, the through hole is any one or more of the following: polygonal through hole, circular through hole, elliptical through hole, fan-shaped through hole, and cross-shaped through hole;

[0029] The polygonal through hole is preferably any one or more of the following: triangular through hole, square through hole, or hexagonal through hole.

[0030] In some embodiments of this application, the trench electrode is a hollow polygonal prism, which is any one of a triangular prism, a cube, or a hexagonal prism.

[0031] In some embodiments of this application, the central electrode and the trench electrode are made of semiconductor materials, which are one or more of Si, Ge, GaN, SiC, HgI2, GaAs, TiBr, CdTe, CdZnTe, CdSe, GaP, HgS, PbI2 or AlSb.

[0032] A second aspect of this application is to provide a method for fabricating a three-dimensional trench electrode detector array, the method comprising:

[0033] Provide a matrix;

[0034] The substrate is etched to form a first trench wall and a second trench wall, the first trench wall and the second trench wall are intersecting and forming an intersection at the intersection;

[0035] Continue etching so that the width of the intersection along the first direction and / or the second direction is not greater than the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction;

[0036] A central electrode is etched inside the detection unit formed by the first trench wall and the second trench wall;

[0037] An insulator is embedded between the central electrode and the trench wall.

[0038] In some embodiments of this application, the etching includes a deep silicon etching process, which includes a Bosch process.

[0039] The fabrication process designed in this application can be implemented without changing the existing trench electrode fabrication process or adding any additional process steps, so it is highly feasible. Attached Figure Description

[0040] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0041] Figure 1 A schematic diagram of the structure of a conventional detector array is shown.

[0042] Figure 2 schematically shown Figure 1 A partial structural diagram of the detector array;

[0043] Figure 3 schematically shown Figure 1 A schematic diagram of the structure of the trench wall located at the junction;

[0044] Figure 4 schematically shown Figure 3 Micro-observation attempts;

[0045] Figure 5 The diagram schematically illustrates the experimental results of trench etching with different widths;

[0046] Figure 6 A schematic diagram of the detector array according to an embodiment of this application is shown.

[0047] Figure 7 schematically shown Figure 6 A schematic diagram of the structure of the trench wall located at the junction;

[0048] Figure 8 schematically shown Figure 7 Top view;

[0049] Figure 9 schematically shown Figure 8 A magnified structural diagram of part C in the middle;

[0050] Figure 10 schematically shown Figure 8 A magnified structural diagram of part C in the middle;

[0051] Figure 11 schematically shown Figure 8 Another structural diagram of the C-section;

[0052] Figure 12 schematically shown Figure 6 A schematic diagram of a structure located on the trench wall at the junction;

[0053] Figure 13 schematically shown Figure 6 Another structural diagram of the trench wall located at the junction;

[0054] Figure 14 A simulation diagram is shown schematically;

[0055] Figure 15 A schematic diagram of the simulation results is shown.

[0056] Figure 16 A schematic diagram of the simulation results is shown.

[0057] The labels in the attached diagram are as follows:

[0058] 1000, detector array; 100, detector element; 200, substrate; 300, junction; 301, bottom tip;

[0059] 2000, Matrix;

[0060] 10. Trench electrode;

[0061] 11. First trench wall; 11a. First wall end; 11b. Second wall end; 11c. First side end; 11d. Second side end;

[0062] 12. Second trench wall;

[0063] 13. Cross position; 13a. First part; 13b. Second part; 13c. Third part; 13d. Fourth part;

[0064] 20. Central electrode;

[0065] 30. Through hole;

[0066] Section C: Magnified area;

[0067] η: The width of the first trench wall or the width of the second trench wall;

[0068] η1: The width of the first trench wall or the second trench wall at the first side end;

[0069] η nThe width of the first trench wall or the second trench wall at the second side end;

[0070] η x The width of the first trench wall or the second trench wall at the position between the first side end and the second side end;

[0071] n1: Width of the cross position along the first or second direction;

[0072] The x-axis direction: the width or length direction of the detection unit; it can also refer to the width or length direction of the trench wall.

[0073] The y-axis direction: the length or width direction of the detection unit; it can also refer to the width or length direction of the trench wall.

[0074] The z-axis direction: the height direction of the detection unit; it can also refer to the depth direction of the trench wall.

[0075] First direction: the x-axis or y-axis direction;

[0076] The second direction: the y-axis or the x-axis.

[0077] Terminology Explanation and English Abbreviations:

[0078] TCAD stands for Semiconductor Process and Device Simulation Software. TCAD is a numerical simulation tool built upon semiconductor physics. It can simulate different process conditions, replacing or partially replacing expensive and time-consuming process experiments; it can also design and optimize different device structures to obtain ideal characteristics; and it can simulate circuit performance and electrical defects. TCAD can reduce production costs by 40% by reducing the number of experiments and shortening development time.

[0079] Bosch: One of the deep silicon etching processes, invented by Laemer and Schilp and patented by Robert Bosch GmbH in 1996, is the alternating reciprocating process. It is currently the most widely used and mature deep silicon etching process. It adds an alternating deposition process to the simple reactive ion etching process, thereby protecting the sidewalls from being etched, obtaining high-depth vertical sidewalls, and achieving a higher aspect ratio while maintaining a high etching selectivity.

[0080] RIE-Lag: Localized etching gas consumption exceeds supply. Etching rate The effects of descent or uneven distribution include loading effects related to the etching aspect ratio. Detailed Implementation

[0081] Existing 3D trench electrode detectors utilize deep silicon etching technology to etch deep trenches into a substrate, such as silicon. These trenches, also known as grooves, are then doped in situ or by ion implantation to form trench electrodes. Compared to traditional 3D cylindrical electrode detectors, the saddle region between similar cylindrical electrodes disappears; this saddle region is also known as a low-electric-field dead region. After the saddle region disappears, the electric field distribution becomes more uniform, and because the trench electrode completely surrounds the central readout electrode, crosstalk between adjacent pixel units is extremely low.

[0082] like Figure 1 As shown, a traditional three-dimensional trench electrode detector array 1000 consists of multiple three-dimensional trench electrode detection units 100. Figure 1 A 2×2 array is illustrated. The three-dimensional trench electrode detection unit 100 includes a substrate 200, and trench electrodes 10 and a central electrode 20 located on the substrate 200. The trench electrodes 10 and the central electrode 20 are isolated by an insulator. In some embodiments of this application, the trench electrodes are n-type doped, the central electrode is p-type doped, and the insulator between the trench electrodes and the central electrode is a depletion region. When an external particle enters the depletion region, it will cause a series of electron-hole pairs. The electron-hole pairs drift under the action of an electric field. Electrons flow to the trench electrodes, and holes flow to the central electrode, forming a current. The current signal can be processed to obtain the relevant information of the incident particle. Therefore, the three-dimensional trench electrode detector array has good application prospects in aerospace, deep space exploration, space exploration, major physics experiments, medicine, X-ray imaging, and military industry.

[0083] Combination Figure 2 , Figure 3 , Figure 4 It is known that the etching depth at the junction 300 of each detector unit 100 in array 1000 is usually greater than that at other adjacent locations. This can easily lead to uneven electric field distribution at the bottom of the device, thus affecting the collection of electrical signals. In a more serious case, the larger etching depth at the array junction 300 causes a bottom tip 301, which may in turn cause electric field concentration, leading to premature breakdown of the device.

[0084] Reducing the etching depth at the junctions of the detector units in the array is a technical problem that urgently needs to be solved by those skilled in the art. The applicant has conducted relevant research, specifically using the Bosch process in deep silicon etching technology as an example. The etching principle of this process is as follows:

[0085] The principle of the first step etching process:

[0086]

[0087] The principle of the second passivation process:

[0088]

[0089] The principle of the third etching process:

[0090]

[0091]

[0092] Process parameters such as bottom electrode bias, cavity pressure, etching gas flow rate, etching time, etching RF power, and passivation gas flow rate all affect etching performance. Additionally, the loading effect in etching hysteresis (RIE-Lag) is related to the etching aspect ratio, manifesting as different etching depths for patterns of different sizes on the same substrate. Wide patterns are etched deeper, and narrow patterns are etched shallower. This application, with fixed process parameters, obtains... Figure 5 The images shown depict the etching results of trenches of different widths, combined with... Figure 5 It is known that, given a fixed process parameter, the trench etching depth is related to the trench width. In some embodiments of this application, the etching depth is selected as... Figure 1 or Figure 3 In the coordinate system, the z-axis represents the trench etching depth, and either the x-axis or y-axis represents the trench width. (See attached diagram.) Figure 5 It can be seen that the wider the groove, the greater the air intake and the deeper the etching depth; conversely, the narrower the groove, the smaller the air intake and the shallower the etching depth.

[0093] Further investigation revealed that, due to the influence of the aforementioned Bosch fabrication process, the air intake at the junction of the array is usually large, which leads to a large etching depth. If the air intake at the junction can be reduced, the etching situation at the junction can be improved.

[0094] Based on the above considerations, to address the issue that the relatively large etching depth at the interface of existing arrays composed of three-dimensional trench electrode detector units can easily lead to uneven electric field distribution at the bottom of the device, a three-dimensional trench electrode detector array and its fabrication method were obtained based on the above design concept and related experimental investigations.

[0095] First, this application provides a three-dimensional trench electrode detector array, which includes detector units; each detector unit includes a central electrode and a trench electrode; such as Figure 6 , Figure 7 The trench electrode includes a first trench wall 11 and a second trench wall 12, which intersect and form a cross position 13 at the intersection. The cross position 13 has a width along a first direction (x-axis) and / or a second direction (y-axis). The first trench wall 11 has a width along the first direction (x-axis), and the second trench wall 12 has a width along the second direction (y-axis).

[0096] Each width satisfies one or two of the following:

[0097] Along the first direction, the width of the intersection is not greater than the width of the first trench wall;

[0098] Along the second direction, the width of the intersection is no greater than the width of the second trench wall.

[0099] In this application, the first direction and the second direction are different. In some embodiments of this application, the first direction refers to the x-axis direction and the second direction refers to the y-axis direction.

[0100] In some embodiments of this application, the above-mentioned detection units are formed on both sides of the first trench wall and both sides of the second trench wall. The detection units form an M×N detector array, where M and N are both positive integers. In the above embodiments, this application only uses a 2×2 array as an illustration. Other arrays that meet the requirements are also within the protection scope of this application.

[0101] In this application, the first trench wall and the second trench wall are any two of the several trench walls constituting the trench electrode. These two trench walls are intersecting and form a cross-section at the intersection. Furthermore, detector array units are formed on both sides of the first trench wall and the second trench wall, and this cross-section serves as a common area for adjacent detector units. Combined with... Figure 8 It can be seen that the common part includes a first part 13a, a second part 13b, a third part 13c, and a fourth part 13d. The first part 13a and the second part 13b are located at opposite ends of the first direction (coordinate axis x-direction), and the third part 13c and the fourth part 13d are also located at opposite ends of the first direction (coordinate axis x-direction). The distance between the first part 13a and the second part 13b, or the distance between the third part 13c and the fourth part 13d, is the width of the intersection 13 along the second direction (coordinate axis y-direction). Similarly, the distance between the first part 13a and the third part 13c, or the distance between the second part 13b and the fourth part 13d, is the width of the intersection 13 along the first direction (coordinate axis x-direction).

[0102] The first trench wall 11 and / or the second trench wall 12 in this application have two opposing sides, such as Figure 9 As shown, the first trench wall 11 includes a first wall end 11a and a second wall end 11b along the first direction (coordinate axis x direction), and the width of the first trench wall 11 along the first direction (coordinate axis x direction) is the distance between the first wall end 11a and the second wall end 11b.

[0103] Combination Figure 9As can be seen, taking the width of the intersection 13 along the first direction (x-axis) as an example, the distance between the second part 13b and the fourth part 13d is n1, and the width of the first trench wall 11 along the first direction (x-axis) is η, satisfying n1≤η. In some embodiments, this application also describes in detail that the width of the intersection 13 along the second direction (y-axis) is not greater than the width of the second trench wall along the second direction (y-axis).

[0104] In this application, by selecting that the width of the cross-position along the first direction (x-axis) and / or the second direction (y-axis) is no greater than the width of the first trench wall along the first direction (x-axis) and / or the width of the second trench wall along the second direction (y-axis), the air intake at the cross-position is reduced compared to existing designs, thus decreasing the etching depth at the cross-position. The probability of a bottom tip appearing at the cross-position is also reduced, effectively improving the non-horizontal distribution at the bottom of the three-dimensional trench electrode detector array. This further improves the uniformity of the electric field distribution at the bottom of the device, thereby enhancing the collection of electrical signals. Furthermore, by increasing the breakdown voltage of the detector device, the probability of premature device breakdown due to electric field concentration is reduced.

[0105] In some embodiments, this application discloses that a first trench wall or a second trench wall has a first side end located near the intersection and a second side end located away from the intersection; wherein the width of the first trench wall along the first direction or the width of the second trench wall along the second direction increases in gradient as it extends from the first end to the second side end.

[0106] Combination Figure 10 As can be seen, taking the width variation of the first trench wall 11 as an example, the first trench wall 11 has a first side end 11c located near the intersection and a second side end 11d located away from the intersection. The width of the first trench wall 11 at the first side end 11c is η1, and the width of the first trench wall 11 at the second side end 11d is η. n Satisfying: η1 < η n The width of the first trench wall 11 extends from η1 to η n The gradient increases. In some embodiments, this application also describes in detail the width variation of the second trench wall 12.

[0107] In some embodiments of this application, the first trench wall or the second trench wall has a first side end located near the intersection and a second side end located away from the intersection; the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction increases gradually from the first side end to the second side end and then decreases gradually.

[0108] Combination Figure 11As can be seen, taking the width variation of the first trench wall 11 as an example, the first trench wall 11 has a first side end 11c located near the intersection and a second side end 11d located away from the intersection. The width of the first trench wall 11 at the first side end 11c is η1, and the width of the first trench wall 11 at the second side end 11d is η. n The width of the first trench wall 11 at the position between the first side end 11c and the second side end 11d is η. x Satisfying η1 < η x η n <η x And η1 and η n The widths may be equal or unequal. This application also describes in detail the variation of the width of the second trench wall 12 in some embodiments.

[0109] In some embodiments of this application, the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction vary linearly and / or nonlinearly as they extend from the first side end to the second side end. Further, the nonlinear variation includes exponential or logarithmic variation.

[0110] This application is in Figure 10 The diagram illustrates that the width of the first trench wall and / or the width of the second trench wall change linearly as they extend from the first side end to the second side end. This application... Figure 11 The diagram illustrates that the width of the first trench wall and / or the width of the second trench wall vary non-linearly as they extend from the first side end to the second side end. Regardless of the variation, the width value of the intersection along the first or second direction is relatively small.

[0111] In some embodiments, this application discloses the width of the first trench wall along a first direction and / or the width of the second trench wall along a second direction, which simultaneously include the aforementioned linear and nonlinear variations.

[0112] In some embodiments of this application, a through hole is provided at the intersection. The central axis of the through hole is aligned with the axial direction of the trench electrode.

[0113] This application can further reduce the air intake volume at the cross position by designing a through hole.

[0114] In some embodiments of this application, the through hole includes, but is not limited to, any one or more of polygonal through holes, circular through holes, elliptical through holes, fan-shaped through holes, and cross-shaped through holes; wherein, polygonal through holes are preferably any one or more of triangular through holes, square through holes, or hexagonal through holes.

[0115] This application discloses, in some embodiments, the design of through holes in a detection array where the width of the first trench wall along a first direction or the width of the second trench wall along a second direction increases as it extends from a first side end to a second side end. For example... Figure 11 Indication.

[0116] This application discloses, in some embodiments, the design of through holes in a detection array where the width of the first trench wall along the first direction or the width of the second trench wall along the second direction first increases and then decreases as it extends from the first side end to the second side end. For example... Figure 12 , Figure 13 Indication.

[0117] This application also discloses, in some embodiments, the design of through holes in a detector array that simultaneously satisfies the above conditions.

[0118] The above only lists the partial through holes formed at some intersections. Through holes with other configurations and shapes are also within the scope of protection of this application. The number, position, size, etc. of the through holes need to be designed in detail in conjunction with each detection unit, which will not be elaborated in this application.

[0119] In some embodiments of this application, the trench electrode is a hollow polygonal prism, which includes, but is not limited to, any one of a triangular prism, a cube, or a hexagonal prism. This application has used a cube as an example in the above embodiments to illustrate the technical solution of this application, but triangular prisms or hexagonal prisms also meet the design requirements of this application.

[0120] In some embodiments of this application, the central electrode and the trench electrode are made of semiconductor materials, including but not limited to one or more of Si, Ge, GaN, SiC, HgI2, GaAs, TiBr, CdTe, CdZnTe, CdSe, GaP, HgS, PbI2 or AlSb.

[0121] In some embodiments of this application, a trench electrode is disclosed located on the outer periphery of a central electrode and forms an internal hollow structure. An insulator is provided inside the internal hollow structure. The insulator can be made of silicon dioxide or other insulating materials.

[0122] Furthermore, this application also provides a method for fabricating a three-dimensional trench electrode detector array, the method comprising:

[0123] A substrate is provided; then the substrate is etched to form a central electrode, trench electrodes, and a substrate; the central electrode and trench electrodes are heavily doped by ion diffusion or in-situ doping, and the substrate is lightly doped.

[0124] Specifically, the trench walls of the trench electrode are etched to form a first trench wall and a second trench wall, which are intersected and form a cross position at the intersection; etching continues so that the width of the cross position along the first direction and / or the second direction is not greater than the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction; a central electrode is etched inside the first trench wall and the second trench wall; an insulator is embedded between the central electrode and the trench wall.

[0125] In some embodiments of this application, in-situ doping or ion diffusion processes are all conventional forms in the art and will not be described in detail here.

[0126] In some embodiments of the application, the deep silicon etching process includes the Bosch process. The Bosch process is any conventional form in the art and will not be described in detail here.

[0127] In some embodiments of the application, the substrate material includes, but is not limited to, a silicon substrate.

[0128] In some embodiments of the application, the substrate is a silicon substrate, which includes, but is not limited to, ultrapure high-resistivity silicon, epitaxial silicon, or SOI.

[0129] Figure 14 The model established for the detection unit of this application, Figure 15 , Figure 16 To utilize simulation results from conventional simulation models in this field, such as TACD, and combine them with... Figure 14 and Figure 15 , Figure 16 It can be seen that the optimal drift surface of the detector array in this application is a horizontal plane perpendicular to the electrodes. It can be observed that when the bottom angle θ is large, the electric field and potential distribution at the bottom of the detector are non-uniform, which slows down carrier collection and reduces charge collection. As tan(θ) decreases, it can be seen that the electric field and potential distribution gradually become uniform, and the consistency improves from top to bottom. This further demonstrates that improving the non-horizontal structure at the bottom of the array has a significant effect on improving the overall performance of the device.

[0130] Therefore, this application effectively improves the non-horizontal distribution state at the bottom of the three-dimensional trench electrode detector array. This is beneficial for improving the uniformity of the electric field distribution at the bottom of the device, thereby enhancing the collection of electrical signals. Thus, the detector array designed in this application has promising application prospects in aerospace, deep space exploration, space exploration, major physics experiments, medicine, X-ray imaging, and military industries.

[0131] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a specific order as described or illustrated, unless the order of execution is explicitly indicated. It should also be understood that additional or alternative steps may be used. The above descriptions are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A three-dimensional trench electrode detector array, characterized in that, The array includes detection units; each detection unit includes: Central electrode; Trench electrode: includes a first trench wall and a second trench wall, the first trench wall and the second trench wall are intersecting and forming an intersection at the intersection, and a through hole is provided on the intersection; The intersection has a width along a first direction and / or a second direction, the first trench wall has a width along the first direction, and the second trench wall has a width along the second direction; Each width satisfies one or two of the following: Along the first direction, the width of the intersection is less than the width of the first trench wall; Along the second direction, the width of the intersection is less than the width of the second trench wall; The first direction is different from the second direction.

2. The array according to claim 1, characterized in that, The first trench wall and / or the second trench wall have a first side end disposed near the intersection and a second side end disposed away from the intersection; The gradient increases as the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction extends from the first side end to the second side end.

3. The array according to claim 1, characterized in that, The first trench wall and / or the second trench wall have a first side end disposed near the intersection and a second side end disposed away from the intersection; When the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction extend from the first side end to the second side end, the gradient first increases and then decreases.

4. The array according to claim 2 or 3, characterized in that, The width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction vary linearly and / or nonlinearly as they extend from the first side end to the second side end.

5. The array according to claim 4, characterized in that, The nonlinear changes include exponential or logarithmic changes.

6. The array according to any one of claims 1 to 3, characterized in that, The detection units are formed on both sides of the first trench wall and both sides of the second trench wall, and the detection units form an M×N detector array, where M and N are both positive integers.

7. The array according to any one of claims 1 to 3, characterized in that, The central axis of the through hole is aligned with the axial direction of the trench electrode.

8. The array according to any one of claims 1 to 3, characterized in that, The through hole is any one or more of the following: polygonal through hole, circular through hole, elliptical through hole, fan-shaped through hole, and cross-shaped through hole. The polygonal through hole is any one or more of the following: triangular through hole, square through hole, or hexagonal through hole.

9. The array according to any one of claims 1 to 3, characterized in that, The groove electrode is a hollow polygonal prism, which can be any one of a triangular prism, a cube, or a hexagonal prism.

10. The array according to any one of claims 1 to 3, characterized in that, The central electrode and the trench electrode are made of semiconductor materials, which are one or more of Si, Ge, GaN, SiC, HgI2, GaAs, TiBr, CdTe, CdZnTe, CdSe, GaP, HgS, PbI2 or AlSb.

11. A method for fabricating a three-dimensional trench electrode detector array, characterized in that, The method includes: Provide a matrix; The substrate is etched to form a first trench wall and a second trench wall, the first trench wall and the second trench wall are intersecting and forming an intersection at the intersection; Continue etching to make the width of the intersection along the first direction and / or the second direction smaller than the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction, and form a through hole on the intersection; A central electrode is etched inside the detection unit formed by the first trench wall and the second trench wall; An insulator is embedded between the central electrode and the trench wall.

12. The method according to claim 11, characterized in that, The etching that forms the first trench wall and the second trench wall, and the etching that makes the width of the intersection along the first direction and / or the second direction smaller than the width of the first trench wall along the first direction and / or the width of the second trench wall along the second direction, both include deep silicon etching processes, which include Bosch processes.

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