Semiconductor single crystal detector and packaging method

Abstract

The invention discloses a semiconductor single crystal detector and a packaging method, and relates to the technical field of semiconductor single crystal detectors. The semiconductor single crystal detector comprises a single crystal, an intermediate layer and a substrate which are stacked, wherein the intermediary layer is used for forming an intermediary region so as to realize connection between the single crystal and the substrate; the first surface of the interposer is provided with bonding pads corresponding to the electrodes on the surface, close to the interposer, of the single crystal, so that the single crystal is connected with the first surface, and the distance between the adjacent electrodes on the surface, close to the interposer, of the single crystal is equal to the distance between the adjacent bonding pads corresponding to the first surface; the second surface is provided with electrodes corresponding to the bonding pads on the surface, close to the intermediary layer, of the substrate, so that the substrate is connected with the second surface, and the distance between the adjacent bonding pads on the surface, close to the intermediary layer, of the substrate is equal to the distance between the adjacent electrodes corresponding to the second surface; wherein the first surface is opposite to the second surface.

Description

Technical Field

[0001] The present disclosure relates to the technical field of semiconductor devices, and more specifically, to a semiconductor single crystal detector and a packaging method. Background Art

[0002] Semiconductor single crystal detectors are high-performance photoelectric or radiation detectors based on single crystal materials, and are widely used in optical communications, medical imaging, environmental monitoring, nuclear physics research and other fields.

[0003] Due to their highly ordered structure and excellent physical properties, single crystal materials can generate electron-hole pairs after absorbing photons or radiation energy, thereby realizing signal detection and conversion.

[0004] However, current semiconductor single crystal detectors usually need to work in an environment that is isolated from water and oxygen. However, existing packaging technology has shortcomings in practical applications. Water molecules and oxygen may penetrate into the material, affecting the stability and reliability of the detector. In addition, the substrate and the single crystal material are prone to inaccurate alignment during welding, which will cause electrode misalignment, thus seriously affecting the reliability and accuracy of signal transmission. Summary of the invention

[0005] In view of this, the present disclosure provides a semiconductor single crystal detector and a packaging method.

[0006] On the one hand, the present disclosure provides a semiconductor single crystal detector, comprising: a stacked single crystal, an intermediate layer and a substrate; wherein the intermediate layer is used to form an intermediate region to connect the single crystal to the substrate; the intermediate layer comprises: a first surface, provided with pads corresponding to electrodes on the surface of the single crystal close to the intermediate layer, so that the single crystal is connected to the first surface, and the spacing between adjacent electrodes on the surface of the single crystal close to the intermediate layer is the same as the spacing between adjacent pads corresponding to the first surface; a second surface, provided with electrodes corresponding to pads on the surface of the substrate close to the intermediate layer, so that the substrate is connected to the second surface, and the spacing between adjacent pads on the surface of the substrate close to the intermediate layer is the same as the spacing between adjacent electrodes corresponding to the second surface; wherein the first surface is opposite to the second surface.

[0007] According to an embodiment of the present disclosure, the semiconductor single crystal detector further includes: electrodes, which are arranged on a surface of the single crystal close to the intermediate layer and a surface away from the intermediate layer.

[0008] According to an embodiment of the present disclosure, the semiconductor single crystal detector further includes: a plurality of probes disposed on a surface of the substrate away from the intermediate layer.

[0009] According to an embodiment of the present disclosure, the semiconductor single crystal detector further includes: a connecting material for connecting an electrode of the single crystal away from the surface of the intermediate layer to the substrate.

[0010] According to an embodiment of the present disclosure, the connection material includes a gold wire, a tin wire or a flexible circuit board.

[0011] According to an embodiment of the present disclosure, the material of the electrode includes a metal material or an organic material.

[0012] Another aspect of the present disclosure discloses a method for packaging a semiconductor single crystal detector, comprising: placing the semiconductor single crystal detector in a mold; filling the mold with epoxy resin and curing it to complete the packaging of the semiconductor single crystal detector; wherein the semi-monomeric single crystal detector comprises: a stacked single crystal, an interposer and a substrate; the interposer is used to form an interposer region to achieve connection between the single crystal and the substrate; the interposer comprises: a first surface, provided with pads corresponding to electrodes on the surface of the single crystal close to the interposer, so that the single crystal is connected to the first surface, and the spacing between adjacent electrodes on the surface of the single crystal close to the interposer is the same as the spacing between adjacent pads corresponding to the first surface; a second surface, provided with electrodes corresponding to pads on the surface of the substrate close to the interposer, so that the substrate is connected to the second surface, and the spacing between adjacent pads on the surface of the substrate close to the interposer is the same as the spacing between adjacent electrodes corresponding to the second surface; wherein the first surface is opposite to the second surface.

[0013] According to an embodiment of the present disclosure, the method further includes: evaporating electrodes on a surface of the single crystal close to the intermediary layer and a surface far from the intermediary layer;

[0014] Connecting the electrode of the single crystal close to the surface of the intermediary layer to the first surface through a fusible alloy or silver paste;

[0015] connecting the electrode of the single crystal away from the surface of the interposer to the substrate through a connecting material;

[0016] Leading out a plurality of probes on a surface of the substrate away from the interposer;

[0017] A mold is placed on a surface of the substrate close to the interposer, wherein the surface of the substrate close to the interposer, the interposer and the single crystal are built into the mold.

[0018] According to an embodiment of the present disclosure, the melting point of the fusible alloy is lower than 100°C.

[0019] According to an embodiment of the present disclosure, the temperature of the curing treatment is 25° C.-60° C., and the curing time is 1 h-24 h.

[0020] According to the embodiments of the present disclosure, an intermediary layer is provided between the single crystal and the substrate, thereby effectively solving the problem of electrode misalignment caused by inaccurate alignment when the single crystal and the substrate are directly welded; and in the case where an array electrode is provided on the surface of the single crystal, precise welding can also be performed through the intermediary layer, thereby realizing the interconnection of multiple electrodes.

[0021] According to the embodiments of the present disclosure, by filling epoxy resin in the mold for packaging, water and oxygen can be effectively isolated, environmental stability can be improved, and the operation is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0023] Figure 1 A schematic diagram of the structure of a semiconductor single crystal detector according to an embodiment of the present disclosure is shown;

[0024] Figure 2 A schematic diagram shows a structure diagram of a semiconductor single crystal detector after packaging according to an embodiment of the present disclosure;

[0025] Figure 3 A schematic diagram of a semiconductor single crystal detector after packaging according to an embodiment of the present disclosure is shown;

[0026] Figure 4 A diagram schematically shows a light response attenuation test of a semiconductor single crystal detector according to an embodiment of the present disclosure after 10,000 cycles;

[0027] Figure 5 A light-dark current decay curve diagram of a semiconductor single crystal detector placed at a humidity of 80% according to an embodiment of the present disclosure is schematically shown;

[0028] Description of reference numerals:

[0029] 1. Probe; 2. Substrate; 3. Intermediary layer; 4. Single crystal; 5. Connection material; 6. Mold; 7. Epoxy resin. DETAILED DESCRIPTION

[0030] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known systems and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0031] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0032] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0033] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0034] Figure 1 The structure diagram of the semiconductor single crystal detector according to the embodiment of the present disclosure is schematically shown.

[0035] like Figure 1 As shown, on the one hand, the present disclosure provides a semiconductor single crystal detector, comprising: a stacked single crystal 4, an intermediate layer 3 and a substrate 2; wherein the intermediate layer 3 is used to form an intermediate region to achieve connection between the single crystal and the substrate; the intermediate layer 3 comprises: a first surface, provided with pads corresponding to electrodes on the surface of the single crystal 4 close to the intermediate layer 3, so that the single crystal 4 is connected to the first surface, and the spacing between adjacent electrodes on the surface of the single crystal close to the intermediate layer is the same as the spacing between adjacent pads corresponding to the first surface; a second surface, provided with electrodes corresponding to pads on the surface of the substrate 2 close to the intermediate layer 3, so that the substrate is connected to the second surface, and the spacing between adjacent pads on the surface of the substrate close to the intermediate layer is the same as the spacing between adjacent electrodes corresponding to the second surface; wherein the first surface is opposite to the second surface.

[0036] In the embodiments of the present disclosure, the surface of the single crystal is usually provided with array electrodes, and the solder joints are small and dense. During the manufacturing process of the substrate, a standardized design is adopted to adapt to different applications and equipment. Therefore, the position and spacing of the pads are pre-designed and fixed. After the substrate is manufactured, the spacing of the pads cannot be changed, and the flexibility is poor. For layouts that require multi-electrode connections, the fixed spacing of the pads can lead to difficulties in alignment and connection. Therefore, if the single crystal is directly connected to the substrate, since the spacing of the pads is greater than the spacing of the electrode solder joints on the single crystal, it will cause slight deviations in the welding position and cannot be accurately matched, which will lead to connection failure or short circuit.

[0037] Based on this, in the embodiments of the present disclosure, an intermediary layer is provided to form an intermediary region, and the solder joints on the single crystal are first aligned and fixed with the pads on the first surface of the intermediary layer, and then the second surface is connected to the substrate by providing solder joints corresponding to the pads on the substrate on the second surface, thereby effectively realizing the flip-chip soldering process of the single crystal. Since the intermediary layer is an independent component that can be designed and manufactured separately, it can be precisely aligned according to the layout of the single crystal electrodes to accommodate single crystal electrodes of different sizes and layouts. Therefore, if an array electrode is provided on the single crystal, when the spacing between adjacent electrodes is smaller than the spacing between adjacent pads corresponding to the substrate, the limitation brought by the fixed spacing between the substrate pads can be overcome by designing the intermediary layer, and the adjustability of the pad spacing can be realized, so that single crystal electrodes of different sizes and layouts can be precisely aligned and connected, thereby improving the reliability and stability of the connection.

[0038] According to an embodiment of the present disclosure, a prefabricated area with a pad is provided on the substrate, and a gold wire can be punched or a flying wire can be connected on the surface of the substrate.

[0039] According to an embodiment of the present disclosure, the interposer may be a substrate having a shape close to that of a single crystal.

[0040] According to an embodiment of the present disclosure, the semiconductor single crystal detector further includes: electrodes, which are arranged on a surface of the single crystal close to the intermediate layer and a surface away from the intermediate layer.

[0041] According to an embodiment of the present disclosure, the material of the electrode includes a metal material or an organic material.

[0042] According to an embodiment of the present disclosure, the metal material includes gold, silver, chromium, etc., and the organic material includes bathocuproine (BCP for short), fullerene (C60), and poly(3,4-ethylenedioxythiophene) (PEDOT).

[0043] According to an embodiment of the present disclosure, the semiconductor single crystal detector further includes: a plurality of probes 1, which are arranged on a surface of the substrate away from the intermediate layer.

[0044] According to the embodiments of the present disclosure, the number of probes can be set as needed.

[0045] In the embodiments of the present disclosure, when using existing large-volume semiconductor single crystal detectors, it is usually necessary to manually connect the wires to the electrodes of the detectors. However, manual connection has low timeliness and is difficult to ensure alignment accuracy. It also has poor interchangeability and requires reconnection and recalibration when using different detectors.

[0046] Based on this, the embodiment of the present disclosure is provided with a plurality of probes on the surface of the substrate away from the interposer, and a pre-buried circuit is provided inside the substrate, and the spacing between the lead-out probes can be adjusted as needed, which can meet the requirements of plug-and-play and is portable to use.

[0047] According to an embodiment of the present disclosure, the semiconductor single crystal detector further includes: a connecting material for connecting an electrode of the single crystal away from the surface of the intermediate layer to the substrate.

[0048] According to an embodiment of the present disclosure, the connection material includes a gold wire, a tin wire or a flexible circuit board.

[0049] In the embodiments of the present disclosure, when the number of electrodes of a single crystal is small, gold wires and tin wires can be selected for connection; when an electrode array is provided on a single crystal, a flexible printed circuit board is more concise.

[0050] According to an embodiment of the present disclosure, the single crystal may be a perovskite single crystal, and the chemical formula is ABX3, wherein A is an organic or inorganic cation, B is a metal cation, and X is a halogen anion. The organic or inorganic cation includes methylamine, formamidinium, and cesium ions, the metal cation includes lead, tin, or germanium ions, and the halogen anions include chloride, bromide, and iodide.

[0051] According to an embodiment of the present disclosure, the perovskite single crystal may be MAPbBr3 or CsPbBr3.

[0052] In the embodiments disclosed herein, the perovskite material has excellent optoelectronic properties such as adjustable direct band gap, high carrier mobility, and high absorption coefficient due to its unique crystal and electronic structure, and has great development prospects in the fields of solar cells, light-emitting diodes, photodetectors, etc. For the common perovskite material lead halide, since it contains high atomic number elements such as Pb, Br, and I, it has a high absorption coefficient for high-energy rays, which can greatly reduce the longitudinal thickness of the absorption layer, which is beneficial to improving the performance of the radiation detector, and can be used for both visible light detection and radiation detection.

[0053] Figure 2 The structure diagram of a semiconductor single crystal detector after packaging according to an embodiment of the present disclosure is schematically shown.

[0054] like Figure 2As shown, another aspect of the present disclosure discloses a packaging method for a semiconductor single crystal detector, comprising: placing a semiconductor single crystal detector in a resin mold 6; filling the resin mold with epoxy resin 7 and curing it to complete the packaging of the semiconductor single crystal detector; wherein the semi-monomeric single crystal detector comprises: a stacked single crystal 4, an intermediate layer 3 and a substrate 2; the intermediate layer is used to form an intermediate region to achieve connection between the single crystal and the substrate; the intermediate layer comprises: a first surface, provided with pads corresponding to electrodes on the surface of the single crystal close to the intermediate layer, so that the single crystal is connected to the first surface, and the spacing between adjacent electrodes on the surface of the single crystal close to the intermediate layer is the same as the spacing between adjacent pads corresponding to the first surface; a second surface, provided with electrodes corresponding to pads on the surface of the substrate close to the intermediate layer, so that the substrate is connected to the second surface, and the spacing between adjacent pads on the surface of the substrate close to the intermediate layer is the same as the spacing between adjacent electrodes corresponding to the second surface; wherein the first surface is opposite to the second surface.

[0055] According to an embodiment of the present disclosure, when the semiconductor single crystal detector is a photoelectric detector, it is packaged using a transparent epoxy resin; when the semiconductor single crystal detector is a radiation detector, it is packaged using an opaque epoxy resin.

[0056] In the embodiments of the present disclosure, the semiconductor single crystal detector is packaged with epoxy resin, which effectively isolates water and oxygen and improves the stability of the detector.

[0057] According to an embodiment of the present disclosure, it also includes: evaporating electrodes on the surface of the single crystal close to the intermediary layer and the surface away from the intermediary layer; connecting the electrode on the surface of the single crystal close to the intermediary layer to the first surface through a fusible alloy or silver paste; connecting the electrode on the surface of the single crystal away from the intermediary layer to the substrate through a connecting material; leading out a plurality of probes 1 on the surface of the substrate away from the intermediary layer; placing a mold on the surface of the substrate close to the intermediary layer, wherein the surface of the substrate close to the intermediary layer, the intermediary layer and the single crystal are built into the mold.

[0058] According to an embodiment of the present disclosure, the mold is a 3D printed resin mold, and the shape of the resin mold can be a square hole type, and the size is close to that of the substrate.

[0059] According to an embodiment of the present disclosure, the melting point of the fusible alloy is lower than 100°C.

[0060] According to the embodiment of the present disclosure, the curing temperature is 25°C-60°C and the curing time is 1h-24h.

[0061] In the embodiments of the present disclosure, a low temperature solidification process is adopted to avoid the influence of higher temperature on the single crystal characteristics.

[0062] Figure 3 The figure schematically shows a semiconductor single crystal detector after packaging according to an embodiment of the present disclosure.

[0063] Figure 4 The optical response attenuation test diagram of the semiconductor single crystal detector according to the embodiment of the present disclosure after 10,000 cycles is schematically shown.

[0064] Figure 5 The light-dark current decay curve of the semiconductor single crystal detector according to the embodiment of the present disclosure is schematically shown when placed in a humidity of 80%.

[0065] like Figure 3 As shown, a possible embodiment of the present disclosure provides a semiconductor single crystal detector, comprising:

[0066] Step 1: Vapor-deposit gold electrodes on the surface of the single crystal close to the interposer and the surface away from the interposer.

[0067] Step 2: Connect the electrode on the surface of the single crystal close to the intermediary layer to the first surface through silver paste.

[0068] Step 3: Connect the electrode of the single crystal away from the surface of the interposer to the substrate through a connecting material.

[0069] Step 4: Lead out a plurality of probes on a surface of the substrate away from the interposer.

[0070] Step 5: Place a 3D printed resin mold on the surface of the substrate close to the interposer and fix it on the substrate as a shell, wherein the surface of the substrate close to the interposer, the interposer and the single crystal are built into the mold.

[0071] Step 6: Fill the resin mold with transparent epoxy resin and cure it at low temperature to complete the packaging.

[0072] The single crystal is MAPbBr3, the length and width of the single crystal are both 1mm-20mm, and a circuit connected to the surface of the single crystal is pre-buried in the substrate.

[0073] In the embodiments of the present disclosure, the single crystal material is a perovskite single crystal, which has a complete lattice structure and is generally more stable than a thin film material. However, when exposed to air for a long time, the surface of the single crystal may still react with water and oxygen in the air, resulting in an increase in the dark current of the detector and a deterioration in the light response. In addition, in the readout circuit, the detector is often directly connected to the preamplifier, which requires that the resistance of the detector remain substantially constant.

[0074] Therefore, in a specific embodiment of the present disclosure, epoxy resin is used to encapsulate the perovskite single crystal, which effectively isolates water and oxygen; and Figure 4 It can be seen that after the packaged detector was tested for 10,000 cycles, the normalized intensity remained at a relatively stable level and did not fluctuate much during the entire cycle, indicating high stability. Figure 5It can be seen that in an environment with a humidity of 80%, the photocurrent and dark current change little with the increase of time, and have excellent stability in the photo-oxygen environment.

[0075] It will be appreciated by those skilled in the art that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations and / or combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways without departing from the spirit and teachings of the present disclosure. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0076] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A semiconductor single crystal detector, characterized in that: include: A single crystal, an intermediary layer and a substrate are stacked; wherein the intermediary layer is used to form an intermediary region to achieve connection between the single crystal and the substrate; The intermediate layer includes: The first surface is provided with pads corresponding to the electrodes on the surface of the single crystal close to the intermediary layer, so that the single crystal is connected to the first surface, and the spacing between adjacent electrodes on the surface of the single crystal close to the intermediary layer is the same as the spacing between adjacent pads corresponding to the first surface; The second surface is provided with electrodes corresponding to the pads on the surface of the substrate close to the interposer, so that the substrate is connected to the second surface, and the spacing between adjacent pads on the surface of the substrate close to the interposer is the same as the spacing between adjacent electrodes corresponding to the second surface; wherein the first surface is opposite to the second surface.

2. The semi-monomeric single crystal detector according to claim 1, characterized in that: Also includes: Electrodes are arranged on a surface of the single crystal close to the intermediate layer and a surface far from the intermediate layer.

3. The semi-monomeric single crystal detector according to claim 1, characterized in that: Also includes: A plurality of probes are arranged on a surface of the substrate away from the intermediate layer.

4. The semi-monomeric single crystal detector according to claim 2, characterized in that: Also includes: A connecting material is used to connect the electrode of the single crystal away from the surface of the interposer to the substrate.

5. The semi-monomeric single crystal detector according to claim 4, characterized in that: The connection material includes gold wire, tin wire or flexible circuit board.

6. The semi-monomeric single crystal detector according to claim 5, characterized in that: The material of the electrode includes a metal material or an organic material.

7. A method for packaging a semiconductor single crystal detector, characterized in that: include: placing a semiconductor single crystal detector in a mold; Filling the mold with epoxy resin and curing it to complete the packaging of the semiconductor single crystal detector; The semi-monocrystalline detector comprises: a stacked single crystal, an intermediate layer and a substrate; the intermediate layer is used to form an intermediate region to achieve connection between the single crystal and the substrate; The intermediate layer includes: The first surface is provided with pads corresponding to the electrodes on the surface of the single crystal close to the intermediary layer, so that the single crystal is connected to the first surface, and the spacing between adjacent electrodes on the surface of the single crystal close to the intermediary layer is the same as the spacing between adjacent pads corresponding to the first surface; The second surface is provided with electrodes corresponding to the pads on the surface of the substrate close to the interposer, so that the substrate is connected to the second surface, and the spacing between adjacent pads on the surface of the substrate close to the interposer is the same as the spacing between adjacent electrodes corresponding to the second surface; wherein the first surface is opposite to the second surface.

8. The method for packaging a semiconductor single crystal detector according to claim 7, characterized in that: Also includes: Vapor depositing electrodes on a surface of the single crystal close to the intermediary layer and a surface far from the intermediary layer; Connecting the electrode of the single crystal close to the surface of the intermediary layer to the first surface through a fusible alloy or silver paste; Connecting the electrode of the single crystal away from the surface of the interposer to the substrate through a connecting material; Leading out a plurality of probes on the substrate away from the surface of the interposer; The mold is placed on a surface of the substrate close to the intermediary layer, wherein the surface of the substrate close to the intermediary layer, the intermediary layer and the single crystal are built into the mold.

9. The packaging method of a semiconductor single crystal detector according to claim 8, characterized in that: The melting point of the fusible alloy is lower than 100°C.

10. The packaging method of a semiconductor single crystal detector according to claim 7, characterized in that: The curing temperature is 25°C-60°C, and the curing time is 1h-24h.

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