Germanium-silicon bonding type photoelectric device and preparation method thereof

Abstract

The invention discloses a germanium-silicon bonding type photoelectric device and a preparation method, the photoelectric device at least comprises a germanium-silicon bonding substrate, the germanium-silicon bonding substrate is formed by bombarding a germanium substrate and a silicon substrate by using a non-metal fast atomic beam at a first set pressure and a first set temperature, the surface of the germanium-silicon bonding substrate is activated, and the bonding capability is enhanced; the photoelectric device structurally comprises a germanium-silicon bonding type PIN detector, and the germanium-silicon bonding type PIN detector structurally comprises but is not limited to a germanium-silicon bonding substrate, an active region electrode, a first back electrode and a first passivation contact layer; the photoelectric device further comprises a germanium-silicon bonding type silicon drift detector, and the germanium-silicon bonding type silicon drift detector structurally comprises but is not limited to a germanium-silicon bonding substrate, a drift electrode, a collector electrode, a second back electrode and a second passivation contact layer. Compared with a traditional PIN detector with a silicon substrate or a germanium substrate and a silicon drift detector, the photoelectric device combines high energy resolution and scattering capability of germanium with low noise and high detection efficiency of silicon so as to realize better detection performance.

Description

Technical Field

[0001] This invention relates to the field of semiconductor device technology, and in particular to a germanium-silicon bonded optoelectronic device and its fabrication method. Background Technology

[0002] Germanium-silicon bonded optoelectronic devices are a type of high-end semiconductor detector. Typically, they include PIN detectors and silicon-based drift detectors (hereinafter referred to as drift detectors). Due to their advantages such as high count rate and high energy resolution, PIN detectors and drift detectors are widely used in energy dispersive X-ray fluorescence spectrometers (XRF) or X-ray energy dispersive spectrometers (EDS), medical equipment, high-energy physics research equipment, aerospace and other fields.

[0003] A germanium-silicon bonded PIN detector consists of a P-type semiconductor layer, an intrinsic semiconductor layer, and an N-type semiconductor layer, representing the anode, intermediate layer, and cathode, respectively. The working principle of the PIN detector is as follows: When radiation passes through the detector and strikes the intrinsic layer, electron-hole pairs are generated. Under the influence of an electric field, the electrons and holes are separated; the electrons move towards the N-type semiconductor layer, and the holes move towards the P-type semiconductor layer. During this movement, a current is generated, called the drift current. The drift current varies with the energy and intensity of the radiation and can be measured and recorded by an external circuit, thus enabling the detection and measurement of radiation.

[0004] Existing detectors using silicon alone exhibit relatively weak light absorption in the near-infrared band, while germanium displays a higher absorption coefficient in this band. Detectors without a germanium-silicon combination may have limited performance in certain applications (such as near-infrared optical communication); germanium typically possesses high energy resolution and scattering capabilities, which are particularly important in applications requiring precise measurement of radiant energy, while detectors using silicon alone may not provide the same high energy resolution. Furthermore, detectors using germanium alone may face greater difficulty and cost when integrated into existing electronic systems. Detectors without a germanium-silicon combination may not simultaneously meet multiple application requirements. For example, in applications requiring consideration of light absorption, energy resolution, and CMOS process compatibility, detectors using either silicon or germanium alone may not provide the optimal solution. Summary of the Invention

[0005] The purpose of this invention is to provide a germanium-silicon bonded optoelectronic device and its fabrication method, so as to solve the problems that pure germanium substrate photodetectors need to be used at liquid nitrogen temperature and that pure silicon substrate detectors have a small detection energy range.

[0006] To solve the above-mentioned technical problems, the basic concept of the technical solution adopted by the present invention is: a germanium-silicon bonding optoelectronic device, comprising a germanium-silicon bonding substrate; wherein the germanium-silicon bonding substrate is formed by bombarding a germanium substrate and a silicon substrate with a non-metallic fast atom beam at a first set pressure and a first set temperature.

[0007] Furthermore, the aforementioned optoelectronic device also includes a germanium-silicon bonding PIN detector.

[0008] The germanium-silicon bonded PIN detector includes: an active region electrode disposed on the front side of the germanium-silicon bonded substrate for collecting carriers in the substrate drift region;

[0009] A first passivation contact layer is disposed on the germanium-silicon bonding substrate to reduce device leakage current;

[0010] A first back electrode is disposed on the back side of the germanium-silicon bonded substrate, providing a reverse bias voltage that allows the charge carriers to move vertically into the substrate drift region.

[0011] Furthermore, the optoelectronic device further includes a germanium-silicon bonded silicon drift detector, which includes: a second passivation contact layer disposed on the germanium-silicon bonded substrate to reduce the leakage current of the optoelectronic device; a drift electrode located on the front side of the germanium-silicon bonded substrate, the drift electrode being used to form a drift region for charge carriers; a collector electrode located on the front side of the germanium-silicon bonded substrate and cooperating with the drift electrode, the collector electrode collecting charge carriers moving through the drift region, thereby converting them into a measurable electrical signal; and a second back electrode for providing a reverse bias voltage to enable the charge carriers to move vertically into the drift region.

[0012] Furthermore, the active region electrode is a doped region of the active region, and a first metal electrode ring is disposed on the active region electrode;

[0013] The first back electrode is a doped plane on the back side of the germanium-silicon bonded substrate, and a second metal electrode ring is disposed at the edge source of the doped plane.

[0014] Furthermore, the current collector electrode is a doped microstrip within the drift region, and a fourth metal electrode ring is disposed on the current collector electrode;

[0015] The second back electrode is a doped plane on the back side of the germanium-silicon bonded substrate, and a fifth metal electrode ring is disposed on the edge source of the doped plane.

[0016] Furthermore, the drift electrode consists of at least two doped microstrips within the drift region, and each drift electrode is provided with a third metal electrode ring.

[0017] Furthermore, the first passivation contact layer and the second passivation contact layer are passivation layers covering the germanium-silicon bonded substrate and the substrate polycrystalline thin film, used to passivate the polycrystalline thin film and reduce the leakage current of the optoelectronic device.

[0018] Furthermore, the germanium-silicon bonded silicon drift detector also includes a high-resistance voltage divider;

[0019] The high-resistance voltage divider is disposed on the front side of the germanium-silicon bonding substrate and is located between two adjacent drift electrodes;

[0020] The high-resistance voltage divider is electrically connected to the two adjacent drift electrodes;

[0021] The grounding ring 36 is disposed outside the front and back protection zones of the germanium-silicon bonding substrate 1. The grounding ring 36 includes a doped grounding ring and a sixth metal electrode ring disposed on the grounding ring 36.

[0022] Furthermore, it also includes a first protection zone disposed outside the active region on the front side of the germanium-silicon bonding substrate and symmetrical with respect to the germanium-silicon bonding substrate, and a second protection zone disposed outside the first back electrode or the second back electrode of the germanium-silicon bonding substrate and symmetrical with respect to the germanium-silicon bonding substrate.

[0023] Alternatively, a third protection zone, symmetrical with respect to the germanium-silicon bonding substrate, may be located outside the drift region on the front side of the germanium-silicon bonding substrate and outside the back electrode of the germanium-silicon bonding substrate.

[0024] Each protection zone includes at least two doping protection rings and a sixth metal electrode ring disposed on the protection rings.

[0025] Furthermore, a method for fabricating a germanium-silicon bonded optoelectronic device, the method comprising,

[0026] S1. At a first set pressure and a first set temperature, a germanium-silicon bonded substrate is prepared by bombarding the surfaces of a germanium substrate and a silicon substrate with a non-metallic fast atom beam.

[0027] S2. Fabricating a germanium-silicon bonded PIN detector, comprising: forming a doped region of an active region electrode on the front side of the germanium-silicon bonded substrate by a doping process, and setting a first metal electrode ring on the active region electrode; forming a doped plane of a first back electrode on the back side of the germanium-silicon bonded substrate by a doping process, and setting a second metal electrode ring on the first back electrode.

[0028] S3. Fabrication of germanium-silicon bonded silicon drift detectors, including,

[0029] On the front side of the germanium-silicon bonded substrate, at least two drift electrode microstrips are formed by doping process and photolithography, and a third metal electrode ring is set on each drift electrode;

[0030] Within the drift region, doped microstrips of current collector electrodes are formed through a doping process, and a fourth metal electrode ring is disposed on them. On the back side of the germanium-silicon bonded substrate, a doped plane of the second back electrode is formed through a doping process, and a fifth metal electrode ring is disposed on its edge.

[0031] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art.

[0032] This application uses a germanium-silicon bonded substrate as the basis of the optoelectronic device of this invention. A precise bonding process tightly bonds the germanium and silicon layers, forming a composite structure with excellent optoelectronic properties. This structure fully utilizes the high light absorption coefficient of germanium in the near-infrared band and the mature technology of silicon in electronic integration. By precisely controlling the bonding process, carrier transport efficiency is improved, thereby ensuring the overall stable and reliable performance of the optoelectronic device. Furthermore, the germanium-silicon bonded PIN detector of this invention combines the high light absorption capability of germanium with the mature manufacturing process of silicon. The PIN detector can achieve efficient photoelectric conversion in the near-infrared and a wider spectral range. The germanium layer, as a light absorption layer, effectively captures photons and generates electron-hole pairs, while the silicon layer, through optimized electric field design, promotes the effective separation and collection of electrons and holes, significantly improving detection efficiency. Thanks to the excellent properties of germanium itself, the PIN detector exhibits excellent energy resolution in radiation detection, accurately distinguishing incident particles or photons of different energies, making it suitable for applications requiring extremely high measurement accuracy.

[0033] The structural design of the PIN detector in this invention enables it to respond quickly to radiation signals, achieve high-speed and continuous data acquisition, and meet the needs of real-time monitoring and analysis.

[0034] This invention, a germanium-silicon bonded silicon drift detector, utilizes the excellent conductivity of silicon-based materials and CMOS process compatibility to achieve efficient collection and processing of drift current. By optimizing the structure of the drift layer, it further enhances signal amplification and noise suppression capabilities, making the measurement results more accurate and reliable.

[0035] The specific embodiments of the present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0036] The accompanying drawings, as part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention, but do not constitute an undue limitation of the invention. Obviously, the drawings described below are merely some embodiments, and those skilled in the art can obtain other drawings based on these drawings without creative effort. In the drawings:

[0037] Figure 1 This is a top view schematic diagram of the structure of a germanium-silicon bonded PIN detector of a germanium-silicon bonded optoelectronic device according to the present invention;

[0038] Figure 2 This is a top view schematic diagram of the structure of a germanium-silicon bonded silicon drift detector of a germanium-silicon bonded optoelectronic device according to the present invention;

[0039] Figure 3 This is a schematic diagram of the AA cross-section structure of a germanium-silicon bonded PIN detector of a germanium-silicon bonded optoelectronic device according to the present invention.

[0040] Figure 4 This is a schematic diagram of the AA cross-section structure of a germanium-silicon bonded silicon drift detector, a germanium-silicon bonded optoelectronic device according to the present invention.

[0041] Figure descriptions: 1. Germanium-silicon bonded substrate; 11. Silicon substrate; 12. Germanium substrate; 2. Germanium-silicon bonded PIN detector; 21. Active region electrode; 22. First back electrode; 23. First passivation contact layer; 3. Germanium-silicon bonded silicon drift detector; 31. Drift electrode; 32. Collector electrode; 33. Second back electrode; 34. Second passivation contact layer; 36. Grounding ring; 37. Guard ring;

[0042] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the invention in any way, but rather to illustrate the concept of the invention to those skilled in the art by referring to specific embodiments. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0044] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0045] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0046] Example 1

[0047] A germanium-silicon bonded optoelectronic device includes at least a germanium-silicon bonded substrate 1. The germanium-silicon bonded substrate 1 is formed by bombarding a germanium substrate 11 and a silicon substrate 12 with a non-metallic fast atom beam at a first set temperature and a pressure greater than a first set temperature. This substrate utilizes advanced non-metallic fast atom beam technology, where, under strictly controlled conditions at a first set temperature and a specific pressure environment above that temperature, a fast atom beam of an inert gas such as argon directly bombards the surfaces of the germanium substrate 11 and the silicon substrate 12, achieving high-strength, high-quality bonding between them. For example, the germanium-silicon bonded substrate 1 is formed by bombarding the germanium substrate 11 and the silicon substrate 12 with a non-metallic fast atom beam of argon.

[0048] Understandably, the use of non-metallic fast atomic beams in this application effectively removes the oxide layer, contamination layer, and micro-defects on the surface of germanium and silicon substrates, promoting direct atomic-level contact and rearrangement, thereby significantly improving the quality and strength of the bonding interface. This high-strength bonding ensures the stability and reliability of optoelectronic devices during long-term use.

[0049] Understandably, by precisely controlling the temperature, pressure, and parameters of the non-metallic fast atom beam (such as beam current intensity and bombardment time) during the bombardment process, a high degree of customization of the bonding process can be achieved, meeting the specific performance requirements of optoelectronic devices in different application scenarios. This technology is not only applicable to the bonding of germanium and silicon, but also has the potential to be applied to combinations of other semiconductor materials, providing a broader scope for material selection and performance optimization of optoelectronic devices.

[0050] Understandably, this application uses inert gas as the bombardment medium, making the entire bonding process non-toxic and pollution-free, aligning with the trend of green manufacturing. Furthermore, this technology facilitates the reuse of waste semiconductor materials, promoting the sustainable development of the semiconductor industry. Compared to traditional bonding technologies, non-metallic fast atom beam bombardment offers higher bonding efficiency and yield, helping to shorten production cycles and reduce manufacturing costs, which is of great significance for the large-scale industrial production of optoelectronic devices.

[0051] In this embodiment, the optoelectronic device further includes a germanium-silicon bonded PIN detector 2, which includes: an active region electrode 21 disposed on the front side of the germanium-silicon bonded substrate 1 for collecting carriers in the substrate drift region; its main function is to efficiently collect carriers generated by the substrate drift region. The optimized design of this electrode ensures rapid collection and transport of carriers, thereby improving the detector's response speed and sensitivity. A first passivation contact layer 23 is disposed on the germanium-silicon bonded substrate 1 to reduce device leakage current. By forming a high-quality passivation layer, unnecessary charge exchange between the substrate and the external environment is effectively isolated, reducing leakage current and thus improving the overall performance and stability of the detector. A first back electrode 22 is disposed on the back side of the germanium-silicon bonded substrate 1, providing a reverse bias voltage that allows the carriers to move vertically into the substrate drift region. Located on the back side of the germanium-silicon bonded substrate 1, it is designed to provide a vertical path for charge carriers to move smoothly into the substrate drift region and form a reverse bias in the region. This invention not only promotes the effective separation and collection of charge carriers, but also enhances the photoelectric conversion efficiency and dynamic range of the detector.

[0052] It is understood that this application enhances the collection efficiency and transmission speed of charge carriers by optimizing the design of the active region electrode 21 and the first back electrode 22, thereby significantly improving the photoelectric conversion efficiency of the germanium-silicon bonded PIN detector 2.

[0053] It is understood that the active region electrode 21 is a doped region of the active region, and a first metal electrode ring is disposed on the active region electrode 21; the first metal electrode ring covers the doped region, and this electrode ring not only provides good electrical contact but also ensures effective current transmission. The first back electrode 22 is a doped plane on the back side of the germanium-silicon bonding substrate 1, and a second metal electrode ring is disposed at the edge of the doped plane. In this application, in order to optimize edge effects and prevent current concentration, the second metal electrode ring is carefully disposed in the edge region of the doped plane. This design not only improves the conductivity uniformity of the back side but also enhances the reliability of the optoelectronic device and prevents performance degradation or damage caused by edge effects.

[0054] In one feasible implementation, the active region electrode 21 is an N-type heavily doped region disposed on the front side of the silicon substrate 11, and the first back electrode 22 is a P-type heavily doped planar region disposed on the back side of the germanium substrate 12. When the first back electrode 22 is connected to the negative terminal of a power supply and a reverse bias voltage is applied, the germanium substrate 12 not only forms a PN junction with the silicon substrate 11, but also provides an electric field for charge carriers to move vertically into the drift region. The active region electrode 21 can be used to collect charge carriers (in this case, electrons) coming from the drift region.

[0055] In this technical solution, the synergistic effect of the electric field formed by the N-type heavily doped active region electrode 21 and the PN junction significantly enhances the electron transport efficiency from the drift region to the collection region, reducing carrier recombination and loss. Furthermore, the PN junction formed between the P-type heavily doped first back electrode 22 and the N-type heavily doped silicon substrate 11 in this application has a well-defined band structure and efficient carrier transport characteristics, providing a stable and efficient operating foundation for the optoelectronic device.

[0056] like Figure 1 and Figure 3 As shown, in one feasible embodiment, the square active region electrode 21 is disposed in the center of the front side of the silicon substrate 11 and is surrounded by a square protective ring 37. Figure 3 As shown, the optoelectronic device further includes a first protective zone symmetrically disposed relative to the silicon substrate 11, outside the active region on the front side of the silicon substrate 11 and outside the first back electrode 22 of the germanium substrate 12; the protective zone includes a plurality of doped protective rings 37 and a sixth metal electrode ring disposed on the protective rings 37. The doped protective rings 37 are also N-type heavily doped regions; preferably, the protective rings 37 and the metal electrodes in the protective zone are symmetrically disposed relative to the silicon substrate 11.

[0057] It is understood that this application effectively prevents external impurities and defects from intruding into the active region by setting an N-type heavily doped guard ring 37 around the active region, thereby improving the reliability and stability of the optoelectronic device. Furthermore, the N-type heavily doped guard ring 37 forms a good electrical isolation layer with the silicon substrate 11, reducing electrical interference between the active region and other regions and improving the electrical performance of the device.

[0058] It is understandable that the sixth metal electrode ring enhances the conductivity of the protection zone, enabling the protection zone to quickly conduct current or signals when needed, thereby improving the response speed and efficiency of the optoelectronic device.

[0059] like Figure 3 As shown, in this technical solution, the active region electrode 21 is a doped region of the active region, and a first metal electrode ring is disposed on the active region electrode 21; the first back electrode 22 is a doped plane on the back side of the germanium-silicon bonding substrate 1, and a second metal electrode ring is disposed at the edge of the doped plane. The first metal electrode ring and the second metal electrode ring are used to provide their respective required voltages; the metal electrodes can be made of various metals or conductive materials such as aluminum, silver, or gold. Additionally, as... Figure 1As shown, in this technical solution, a first passivation contact layer 23 for isolation and passivation is provided in the N-type heavily doped region below the active region electrode 21, between the N-type heavily doped region of the guard ring 37 and the silicon substrate 11, and on the back side of the germanium substrate 12, ultimately reducing the leakage current of the optoelectronic device. The first passivation contact layer 23 can be made of materials such as silicon oxide, silicon nitride, or aluminum oxide.

[0060] It is understood that this application simplifies the electrode structure and reduces resistance by directly placing the first metal electrode ring on the active region electrode 21, thereby improving the efficiency of electron collection. The extensive doping plane and edge design of the second metal electrode ring on the first back electrode 22 make voltage application more flexible and convenient, facilitating adjustments according to different application scenarios.

[0061] Understandably, the use of high-quality conductive materials such as aluminum, silver, and gold to make the metal electrode ring ensures stable and efficient voltage transmission and reduces energy loss. This application effectively isolates the functional areas by setting the first passivation contact layer 23, preventing mutual interference in electrical performance, and reducing leakage current of the optoelectronic device through its excellent passivation effect.

[0062] It is understood that the silicon substrate 11 and the germanium substrate 12 are lightly doped; the active region electrode 21 and the guard ring 37 are heavily doped.

[0063] In addition to the aforementioned optoelectronic devices, the optoelectronic devices described in this specification can be fabricated using any method in the prior art. For example, one method for fabricating the aforementioned optoelectronic devices includes, but is not limited to, the following steps:

[0064] I. A silicon substrate 11 of high purity and high resistance of type N and high purity of type P, which are polished on the front and back sides, is provided;

[0065] 2. The first passivation contact layer 23 is deposited on the front side of the semiconductor silicon substrate 11 and the back side of the germanium substrate 12, respectively;

[0066] 3. Photolithography is used to etch an N-type doped region on the front side of the semiconductor silicon substrate 11 to form an opening, exposing the area to be prepared later.

[0067] 4. Phosphorus or arsenic is injected into the formed opening to form the active region electrode 21 and the guard ring 37, which are N-type doped.

[0068] 5. Photolithography is performed on the front side of the semiconductor silicon substrate 11, and the metal electrode formation area is etched out to form an opening, exposing the area where the metal electrode needs to be deposited later.

[0069] 6. Metal is deposited on the front side of the semiconductor silicon substrate 11, and the front side is photolithographically etched to form metal electrodes;

[0070] Metal is deposited on the back side of the semiconductor germanium substrate 12, and the back side is photolithographically etched to form metal electrodes.

[0071] In this technical solution, the optoelectronic device further includes a germanium-silicon bonded silicon drift detector 3.

[0072] The germanium-silicon bonded silicon drift detector 3 includes: a second passivation contact layer 34 disposed on the germanium-silicon bonded substrate 1 to reduce the leakage current of the optoelectronic device; a drift electrode 31 located on the front side of the germanium-silicon bonded substrate 1, the drift electrode 31 being used to form a drift region for charge carriers; a collector electrode 32 located on the front side of the germanium-silicon bonded substrate 1 and cooperating with the drift electrode 31, the collector electrode 32 collecting charge carriers moving through the drift region, thereby converting them into a measurable electrical signal; and a second back electrode 33 used to provide a reverse bias voltage to enable the charge carriers to move vertically into the drift region, thereby increasing the sensitivity and response speed of the detector.

[0073] It is understood that by providing the second passivation contact layer 34 on the germanium-silicon bonding substrate 1, this application can effectively isolate the influence of impurities and defects on the internal structure of the optoelectronic device and reduce the leakage current of the optoelectronic device. This improvement of this application can not only improve the energy efficiency of the device, but also extend its service life.

[0074] It is understood that the drift electrode 31 of this application is disposed on the front side of the germanium-silicon bonded substrate 1, forming a highly efficient carrier drift region, which enables the carriers to move rapidly along a predetermined path under the action of an electric field, reducing recombination and scattering, and improving the carrier collection efficiency.

[0075] Understandably, the current collector electrode 32 and the drift electrode 31 work closely together to efficiently collect charge carriers moving through the drift region and convert them into measurable electrical signals. This process is not only fast and accurate but also enhances the signal output capability of the detector. Furthermore, the second back electrode 33 provides a reverse bias voltage to the detector, allowing charge carriers to move vertically into the drift region. This bias voltage not only increases the detector's sensitivity but also accelerates the movement speed of the charge carriers, thereby significantly improving the detector's response speed.

[0076] In one feasible implementation, the current collector 32 is a doped microstrip in the drift region, and a fourth metal electrode ring is disposed on the current collector 32; the second back electrode 33 is a doped plane on the back side of the germanium-silicon bonding substrate 1, and a fifth metal electrode ring is disposed on the edge source of the doped plane.

[0077] In one feasible implementation, the drift electrode 31 is at least two doped microstrips within the drift region, and each drift electrode 31 is provided with a third metal electrode ring.

[0078] In this technical solution, the first passivation contact layer 23 and the second passivation contact layer 34 of the germanium-silicon bonded PIN detector 2 and the germanium-silicon bonded silicon drift detector 3 are passivation layers covering the germanium-silicon bonded substrate 1 and the substrate polycrystalline thin film, used to passivate the polycrystalline thin film and reduce the leakage current of the optoelectronic device.

[0079] In one feasible implementation, the current collector 32 is designed as a doped microstrip within the drift region. This structure helps to more precisely control the collection path of charge carriers and reduce carrier losses during transport. Simultaneously, the fourth metal electrode ring on the current collector 32 not only provides good electrical contact but also enhances the output capability of the electrical signal, enabling the collected charge carriers to be more effectively converted into electrical signals.

[0080] In one feasible implementation, the drift electrode 31 is designed as at least two doped microstrips within the drift region, and each drift electrode is provided with the third metal electrode ring. This multi-electrode design allows for more flexible control of the electric field distribution within the drift region, thereby optimizing the drift path and velocity of charge carriers. Furthermore, the multi-electrode structure can reduce electric field inhomogeneities within the drift region, lower noise and interference, and improve the signal-to-noise ratio of the detector.

[0081] In this technical solution, the germanium-silicon bonded silicon drift detector 3 further includes a high-resistance voltage divider; the high-resistance voltage divider is disposed on the front side of the germanium-silicon bonded substrate 1 and located between two adjacent drift electrodes 31; the high-resistance voltage divider is electrically connected to the two adjacent drift electrodes.

[0082] Understandably, the high-resistivity voltage divider is disposed on the front side of the germanium-silicon bonded substrate 1, located between two adjacent drift electrodes 31, and electrically connected to them. This design in this application helps to form a more uniform and precise electric field distribution within the drift region. The uniformity of the electric field is crucial for the drift path and velocity of charge carriers, directly affecting the sensitivity and resolution of the detector. Furthermore, the high-resistivity voltage divider ensures that incident particles of different energies generate drift paths of different lengths during drift, thereby being more accurately identified and distinguished, improving the energy resolution of the detector.

[0083] It is understood that the high-resistance voltage divider introduced in this application also helps to reduce noise and interference inside the detector, thereby improving detection accuracy.

[0084] In one feasible implementation, the collector electrode 32 is an N-type heavily doped region disposed on the front side of the silicon substrate 11. When the collector electrode 32 is connected to the positive terminal of the power supply and subjected to zero bias, the collector electrode 32 can be used to collect charge carriers (in this case, the charge carriers are electrons) coming from the drift region.

[0085] In this technical solution, the drift electrode 31 is disposed on the front side of the substrate 11 and is used to form a drift region for charge carriers. It is understood that the substrate 11 is a high-resistivity N-type lightly doped silicon substrate. Correspondingly, the drift electrode 31 is a P-type heavily doped region disposed on the front side of the substrate 11. When the drift electrode 31 is connected to the negative terminal of a power supply and a reverse bias voltage is applied, a PN junction is formed between the drift electrode 31 and the substrate 11, and a lateral electric field is also provided for the movement of charge carriers towards the collector electrode 32 within the drift region.

[0086] Understandably, the collector electrode 32 is designed as an N-type heavily doped region and connected to the positive terminal of the power supply with zero bias, effectively promoting the flow of electrons (charge carriers) from the drift region to the collector electrode 32. The heavily doped N-type region provides a low-resistance path, enabling electrons to be collected quickly and efficiently, thereby improving the current handling capability and efficiency of the optoelectronic device. The drift electrode 31, as a P-type heavily doped region, is disposed on the front side of the silicon substrate 11 and connected to the negative terminal of the power supply with reverse bias, forming a PN junction together with the lightly doped N-type substrate 11. This structure not only achieves unidirectional current conduction but also enhances the depletion layer width of the PN junction through reverse bias, providing a stronger electric field driving force for the lateral movement of charge carriers in the drift region. This electric field control mechanism enhances the device's ability to control the direction and speed of charge carrier movement, helping to optimize the switching characteristics and stability of the optoelectronic device.

[0087] In one feasible implementation, the second back electrode 33 is a heavily p-doped planar region disposed on the back side of the substrate 12. When the second back electrode 33 is connected to the negative terminal of a power supply and a reverse bias is applied, the back electrode 33, the germanium substrate 12, and the silicon substrate 11 not only form a PN junction, but also provide an electric field for the vertical movement of charge carriers into the drift region.

[0088] In one feasible implementation, when the PN junction formed between the drift electrode 31 and the substrate 11 is reverse-biased, the substrate 11 is continuously depleted from the front towards its interior. Conversely, when the PN junction formed between the second back electrode 33, the germanium substrate 12, and the silicon substrate 11 is reverse-biased, the germanium substrate 12 and the substrate 11 are continuously depleted from the interior towards both sides. By setting a reasonable reverse voltage for the drift electrode 31 and the second back electrode 33, a complete depletion layer can be formed on the entire germanium substrate 12 and the silicon substrate 11, with a carrier drift region forming in the middle region of the complete depletion layer. When high-energy rays irradiate the drift region via the second back electrode 33, the holes in the electron-hole pairs formed by their ionization are rapidly absorbed by the back electrode 33, while free electrons move towards the collector electrode 32 and are collected under the influence of the vertical and transverse electric fields in the drift region.

[0089] like Figure 2 As shown, in one feasible embodiment, the circular current collector 32 is disposed in the center of the front drift region of the silicon substrate 11 and is surrounded by the annular drift electrode 31, with an annular protective ring 37 and a grounding ring 36 on the periphery.

[0090] like Figure 2 As shown, in this technical solution, the optoelectronic device further includes a third protective zone symmetrically arranged relative to the silicon substrate 11, located outside the drift region on the front side of the silicon substrate 11 and outside the second back electrode 33 of the germanium substrate 12. The third protective zone includes multiple doped protective rings 37 and a sixth metal electrode disposed on the protective rings 37. The doped protective rings 37 are also heavily p-type doped regions. In this technical solution, the protective rings 37 and the sixth metal electrode in the third protective zone are symmetrically arranged relative to the silicon substrate 11.

[0091] It is understood that the guard ring 37 described in this application, as a heavily p-type doped region, can effectively suppress edge effects and reduce electric field concentration and leakage current occurring in the edge region of the optoelectronic device. This application helps to improve the breakdown voltage and reverse leakage current characteristics of the device, thereby improving the reliability and stability of the optoelectronic device. In addition, the symmetrical arrangement of multiple guard rings 37 can further optimize the electric field distribution inside the optoelectronic device, making the electric field more uniform inside the device, which helps to reduce the thermal effects and potential breakdown risk caused by electric field concentration, while improving the switching speed and efficiency of the device.

[0092] like Figure 2As shown, in one feasible embodiment, the optoelectronic device further includes a grounding ring 36 disposed outside the protection zones on the front side of the silicon substrate 11 and the back side of the germanium substrate 12. The grounding ring 36 is also an N-type heavily doped region and is symmetrically disposed relative to the germanium substrate 12.

[0093] In this technical solution, the grounding ring 36 can conduct the static charge inside the optoelectronic device to the ground, reducing the damage of static electricity to the internal structure of the optoelectronic device. Furthermore, due to the symmetrical arrangement of the grounding ring 36, this application can optimize the current distribution inside the optoelectronic device, reducing the thermal effects and local damage caused by uneven current distribution.

[0094] It is understood that the grounding ring 36, as an N-type heavily doped region, has good conductivity, which helps to quickly dissipate the heat generated during device operation and reduce the device temperature through thermal diffusion, preventing performance degradation or damage caused by excessive temperature.

[0095] In one feasible implementation, such as Figure 2 As shown, the N-type heavily doped region below the current collector 32, the P-type heavily doped region below the drift electrode 31, the P-type heavily doped region in the guard ring 37 and the ground ring 36 between the P-type heavily doped region and the silicon substrate 11, and the back side of the germanium substrate 12 are all provided with a second passivation contact layer 34 for isolation and passivation, ultimately reducing the leakage current of the optoelectronic device. The second passivation contact layer 34 can be made of materials such as silicon oxide, silicon nitride, or aluminum oxide.

[0096] The second passivation contact layer 34 of this application is made of materials such as silicon oxide, silicon nitride, or aluminum oxide, which have good insulation properties. It effectively isolates the heavily doped N-type region below the current collector 32, the heavily doped P-type region below the drift electrode 31, the heavily doped P-type region in the guard ring 37 and the ground ring 36 from the silicon substrate 11, and the back surface of the germanium substrate 12. This application significantly reduces the leakage current that may be generated during the operation of the optoelectronic device, improving the overall performance and stability of the optoelectronic device.

[0097] It is understood that in the optoelectronic device, the drift electrode 31, the collector electrode 32, the guard ring 37, the ground ring 36, and the second back electrode 33 can be formed by various processes already available in the semiconductor manufacturing field, such as ion implantation, diffusion, and deposition of N-type amorphous silicon followed by high-temperature propulsion.

[0098] In this technical solution, the silicon substrate 11 and the germanium substrate 12 are lightly doped; the drift electrode 31, the collector electrode 32, the guard ring 37, the ground ring 36, and the second back electrode 33 are all heavily doped.

[0099] In addition to the aforementioned optoelectronic devices, the optoelectronic devices described in this specification can be fabricated using any method in the prior art. One method for fabricating the aforementioned optoelectronic devices is provided herein, including but not limited to the following steps:

[0100] 1. Provide an N-type high-purity, high-resistivity silicon substrate 11 and a P-type high-purity germanium substrate 11 with polished front and back sides; deposit the second passivation contact layer 34 on the front side of the semiconductor silicon substrate 11 and the back side of the germanium substrate 12, respectively;

[0101] 2. Photolithography is used to etch an N-type doped region on the front side of the silicon substrate 11 to form an opening, exposing the area to be prepared later.

[0102] 3. Inject phosphorus or arsenic into the formed opening to form the current collector 32 and the grounding ring 36, which are of the N-type doping type;

[0103] 4. Photolithography is used to etch a P-type doped region on the front side of the silicon substrate 11 to form an opening, exposing the area to be prepared later.

[0104] 5. Inject boron or gallium into the formed opening to form the drift electrode 31 with a doping type of P and the protective ring 37 on the front side;

[0105] 6. Photolithography is used to etch the front side of the silicon substrate 11 to form a metal electrode formation area, forming an opening to expose the area where metal electrodes need to be deposited subsequently.

[0106] 7. Metal is deposited on the front side of the silicon substrate 11 of the semiconductor, and the front side is photolithographically etched and etched to form metal electrodes;

[0107] Metal is deposited on the back side of the germanium substrate 12 of the semiconductor, and the back side is photolithographically etched to form metal electrodes.

[0108] In one feasible embodiment, the optoelectronic device further includes a first protection zone disposed outside the active region on the front side of the germanium-silicon bonding substrate 1 and symmetrical with respect to the germanium-silicon bonding substrate 1, and a second protection zone disposed outside the first back electrode 22 or the second back electrode 33 of the germanium-silicon bonding substrate 1 and symmetrical with respect to the germanium-silicon bonding substrate 1; or a third protection zone disposed outside the drift region on the front side of the germanium-silicon bonding substrate 1 and symmetrical with respect to the germanium-silicon bonding substrate 1 outside the back electrode of the germanium-silicon bonding substrate 1; each protection zone includes at least two doping protection rings 37 and a sixth metal electrode ring disposed on the protection rings 37.

[0109] In this technical solution, the germanium-silicon bonded silicon drift detector 3 further includes a grounding ring 36, which is disposed outside the front and back protection zones of the germanium-silicon bonded substrate 1; the grounding ring 36 includes a doped grounding ring and a sixth metal electrode ring disposed on the grounding ring 36.

[0110] Example 2

[0111] A method for fabricating a germanium-silicon bonded optoelectronic device, the method comprising: S1, preparing a germanium-silicon bonded substrate 1 by bombarding the surfaces of a germanium substrate 11 and a silicon substrate 12 with a non-metallic fast atom beam at a first set pressure and a first set temperature;

[0112] In one feasible implementation, the method further includes fabricating the germanium-silicon bonding PIN detector 2, specifically including:

[0113] I. A silicon substrate 11 of high purity and high resistance of type N and high purity of type P, which are polished on the front and back sides, is provided;

[0114] 2. The first passivation contact layer 23 is deposited on the front side of the semiconductor silicon substrate 11 and the back side of the germanium substrate 12, respectively;

[0115] 3. Photolithography is used to etch an N-type doped region on the front side of the semiconductor silicon substrate 11 to form an opening, exposing the area to be prepared later.

[0116] 4. Phosphorus or arsenic is injected into the formed opening to form the active region electrode 21 and the guard ring 37, which are N-type doped.

[0117] 5. Photolithography is performed on the front side of the semiconductor silicon substrate 11, and the metal electrode formation area is etched out to form an opening, exposing the area where the metal electrode needs to be deposited later.

[0118] 6. Metal is deposited on the front side of the semiconductor silicon substrate 11, and the front side is photolithographically etched to form metal electrodes;

[0119] Metal is deposited on the back side of the semiconductor germanium substrate 12, and the back side is photolithographically etched to form metal electrodes.

[0120] In one feasible implementation, the method further includes fabricating the germanium-silicon bonded silicon drift detector 3, specifically including:

[0121] 1. Provide an N-type high-purity, high-resistivity silicon substrate 11 and a P-type high-purity germanium substrate 11 with polished front and back sides; deposit the second passivation contact layer 34 on the front side of the semiconductor silicon substrate 11 and the back side of the germanium substrate 12, respectively;

[0122] 2. Photolithography is used to etch an N-type doped region on the front side of the silicon substrate 11 to form an opening, exposing the area to be prepared later.

[0123] 3. Inject phosphorus or arsenic into the formed opening to form the current collector 32 and the grounding ring 36, which are of the N-type doping type;

[0124] 4. Photolithography is used to etch a P-type doped region on the front side of the silicon substrate 11 to form an opening, exposing the area to be prepared later.

[0125] 5. Inject boron or gallium into the formed opening to form the drift electrode 31 with a doping type of P and the protective ring 37 on the front side;

[0126] 6. Photolithography is used to etch the front side of the silicon substrate 11 to form a metal electrode formation area, forming an opening to expose the area where metal electrodes need to be deposited subsequently.

[0127] 7. Metal is deposited on the front side of the silicon substrate 11 of the semiconductor, and the front side is photolithographically etched and etched to form metal electrodes;

[0128] Metal is deposited on the back side of the germanium substrate 12 of the semiconductor, and the back side is photolithographically etched to form metal electrodes.

[0129] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. The implementation schemes in the above embodiments can also be further combined or replaced. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A germanium-silicon bonding type optoelectronic device, characterized in that, include, Germanium-silicon bonded substrate (1), The germanium-silicon bonded substrate (1) is formed by bombarding a germanium substrate (11) and a silicon substrate (12) with a non-metallic fast atom beam at a first set pressure and a first set temperature.

2. The germanium-silicon bonding optoelectronic device according to claim 1, characterized in that, The aforementioned optoelectronic device also includes a germanium-silicon bonded PIN detector (2). The germanium-silicon bonded PIN detector (2) includes: an active region electrode (21) disposed on the front side of the germanium-silicon bonded substrate (1) for collecting carriers in the substrate drift region; A first passivation contact layer (23) is disposed on the germanium-silicon bonding substrate (1) to reduce device leakage current; A first back electrode (22) is disposed on the back side of the germanium-silicon bonded substrate (1) and provides a reverse bias voltage that allows the charge carriers to move vertically into the substrate drift region.

3. A germanium-silicon bonding optoelectronic device according to claim 2, characterized in that, The aforementioned optoelectronic device also includes a germanium-silicon bonded silicon drift detector (3). The germanium-silicon bonded silicon drift detector (3) includes: The second passivation contact layer (34) is disposed on the germanium-silicon bonding substrate (1) to reduce the leakage current of the optoelectronic device; A drift electrode (31) is located on the front side of the germanium-silicon bonding substrate (1), and the drift electrode (31) is used to form a drift region for charge carriers; The collector electrode (32) is located on the front side of the germanium-silicon bonded substrate (1) and cooperates with the drift electrode (31). The collector electrode (32) collects the charge carriers that move through the drift region and converts them into a measurable electrical signal. The second back electrode (33) is used to provide a reverse bias to enable the charge carriers to move vertically into the drift region.

4. A germanium-silicon bonding optoelectronic device according to claim 2, characterized in that, The active region electrode (21) is a doped region of the active region, and a first metal electrode ring is provided on the active region electrode (21); The first back electrode (22) is a doped plane on the back side of the germanium-silicon bonding substrate (1), and a second metal electrode ring is provided at the edge of the doped plane.

5. A germanium-silicon bonding optoelectronic device according to claim 3, characterized in that, The current collector (32) is a doped microstrip in the drift region, and a fourth metal electrode ring is provided on the current collector (32); The second back electrode (33) is a doped plane on the back side of the germanium-silicon bonding substrate (1), and a fifth metal electrode ring is provided on the edge source of the doped plane.

6. A germanium-silicon bonding optoelectronic device according to claim 3, characterized in that, The drift electrode (31) consists of at least two doped microstrips within the drift region, and each drift electrode (31) is provided with a third metal electrode ring.

7. A germanium-silicon bonding optoelectronic device according to any one of claims 2-3, characterized in that, The first passivation contact layer (23) and the second passivation contact layer (34) are passivation layers covering the germanium-silicon bonding substrate (1) and the substrate polycrystalline thin film, used to passivate the polycrystalline thin film and reduce the leakage current of the optoelectronic device.

8. A germanium-silicon bonding optoelectronic device according to claim 6, characterized in that, The germanium-silicon bonded silicon drift detector (3) also includes a high-resistance voltage divider and a grounding ring (36); The high-resistance voltage divider is disposed on the front side of the germanium-silicon bonding substrate (1) and is located between two adjacent drift electrodes (31); The high-resistance voltage divider is electrically connected to the two adjacent drift electrodes; The grounding ring (36) is disposed outside the front and back protection zones of the germanium-silicon bonding substrate (1); The grounding ring (36) includes a doped grounding ring and a sixth metal electrode ring disposed on the grounding ring (36).

9. A germanium-silicon bonding optoelectronic device according to claim 7, characterized in that, It also includes a first protection zone disposed outside the active region on the front side of the germanium-silicon bonding substrate (1) and symmetrical with respect to the germanium-silicon bonding substrate (1), and a second protection zone disposed outside the first back electrode (22) or the second back electrode (33) of the germanium-silicon bonding substrate (1) and symmetrical with respect to the germanium-silicon bonding substrate (1). Alternatively, a third protection zone, symmetrical with respect to the germanium-silicon bonding substrate (1), may be provided outside the drift region on the front side of the germanium-silicon bonding substrate (1) and outside the back electrode of the germanium-silicon bonding substrate (1). Each protected zone includes at least two doped protective rings (37) and a sixth metal electrode ring disposed on the protective rings (37).

10. A method for fabricating a germanium-silicon bonded optoelectronic device, wherein the fabrication method employs a germanium-silicon bonded optoelectronic device as described in any one of claims 1-9, characterized in that... The method includes, S1. At a first set pressure and a first set temperature, a germanium-silicon bonded substrate (1) is prepared by bombarding the surfaces of a germanium substrate (11) and a silicon substrate (12) with a non-metallic fast atom beam. S2, Fabrication of a germanium-silicon bonded PIN detector (2), including, On the front side of the germanium-silicon bonding substrate (1), a doped region of an active region electrode (21) is formed by a doping process, and a first metal electrode ring is disposed on the active region electrode (21). On the back side of the germanium-silicon bonding substrate (1), a doped plane of the first back electrode (22) is formed by a doping process, and a second metal electrode ring is disposed on the first back electrode (22); S3. Fabrication of germanium-silicon bonded silicon drift detector (3), including, On the front side of the germanium-silicon bonding substrate (1), at least two doped microstrips of drift electrodes (31) are formed by doping processes and photolithography, and a third metal electrode ring is disposed on each drift electrode. Within the drift region, doped microstrips of the current collector electrode (32) are formed through a doping process, and a fourth metal electrode ring is disposed on them. On the back side of the germanium-silicon bonded substrate (1), a doped plane of a second back electrode (33) is formed by a doping process, and a fifth metal electrode ring is provided at its edge source.

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