Photoelectric detector and manufacturing method thereof

Abstract

The embodiment of the invention discloses a photoelectric detector and a manufacturing method thereof. The photoelectric detector comprises a substrate; the first electrode structure, the light absorption layer and the second electrode structure are sequentially stacked on the substrate; the first electrode structure comprises a plurality of first conductive parts which are arranged at intervals in the first direction; the first conductive part extends along a second direction; wherein the first conductive part is configured to receive a first voltage, so that a first doped region is formed in the light absorption layer; the second direction and the first direction are parallel to the plane where the substrate is located and intersect with each other; the second electrode structure comprises a plurality of second conductive parts which are arranged at intervals in the first direction, and the second conductive parts extend in the second direction; wherein the second conductive part is configured to receive a second voltage, so that a second doped region is formed in the light absorption layer; the second voltage is different from the first voltage; the second doped region and the first doped region are different in conductive type and at least partially contact.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the field of optoelectronic technology, and in particular, to a photoelectric detector and a method for manufacturing the same. Background Art

[0002] As one of the key optoelectronic devices in optical communication, optical interconnection and optoelectronic integration technology, photodetectors are currently widely used in various fields of military and national economy.

[0003] However, current silicon-based photodetectors have problems such as narrow response band, low responsivity, and complex and time-consuming manufacturing process. Summary of the invention

[0004] According to a first aspect of an embodiment of the present disclosure, there is provided a photodetector, comprising:

[0005] substrate;

[0006] A first electrode structure, a light absorbing layer, and a second electrode structure stacked sequentially on the substrate;

[0007] The first electrode structure comprises a plurality of first conductive portions spaced apart along a first direction; the first conductive portions extend along a second direction; wherein the first conductive portions are configured to receive a first voltage so as to form a first doped region in the light absorbing layer; the second direction and the first direction are parallel to the plane where the substrate is located, and the second direction and the first direction intersect;

[0008] The second electrode structure includes a plurality of second conductive portions spaced apart along the first direction, and the second conductive portions extend along the second direction; wherein the second conductive portions are configured to receive a second voltage so as to form a second doped region in the light absorbing layer; the second voltage is different from the first voltage; and the second doped region and the first doped region have different conductivity types and are at least partially in contact.

[0009] In some embodiments, an orthographic projection of the second conductive portion and an orthographic projection of the first conductive portion at least partially overlap.

[0010] In some embodiments, the orthographic projections of the plurality of second conductive portions and the orthographic projections of the plurality of first conductive portions are alternately arranged along the first direction.

[0011] In some embodiments, the first electrode structure further includes a third conductive portion extending along the first direction; the second electrode structure further includes a fourth conductive portion extending along the first direction;

[0012] Among them, the third conductive part and the fourth conductive part are respectively located on two opposite sides of the light absorbing layer along the second direction; one end of the first conductive part away from the fourth conductive part is connected to the third conductive part, and one end of the second conductive part away from the third conductive part is connected to the fourth conductive part.

[0013] In some embodiments, the photodetector further includes: a first contact electrode and a second contact electrode; wherein the first contact electrode and the second contact electrode are respectively located on two opposite sides of the light absorbing layer along the first direction and connected to the light absorbing layer.

[0014] In some embodiments, the material of the light absorbing layer includes at least one of graphene, molybdenum disulfide, black phosphorus, perovskite or quantum dot materials.

[0015] According to a second aspect of an embodiment of the present disclosure, a method for manufacturing a photodetector is provided, comprising:

[0016] providing a substrate;

[0017] A first electrode structure is formed on the substrate; wherein the first electrode structure comprises a plurality of first conductive portions spaced apart along a first direction; the first conductive portions extend along a second direction; the second direction and the first direction are parallel to the plane where the substrate is located, and the second direction and the first direction intersect;

[0018] forming a light absorbing layer on the first electrode structure;

[0019] A second electrode structure is formed on the light absorbing layer; wherein the second electrode structure includes a plurality of second conductive portions spaced apart along the first direction, and the second conductive portions extend along the second direction; the first conductive portion is configured to receive a first voltage so as to form a first doped region in the light absorbing layer; the second conductive portion is configured to receive a second voltage so as to form a second doped region in the light absorbing layer; the second voltage is different from the first voltage; the second doped region and the first doped region have different conductivity types and are at least partially in contact.

[0020] In some embodiments, forming a first electrode structure on the substrate includes:

[0021] forming a first conductive material layer covering the substrate;

[0022] Forming a patterned first photoresist layer on the first conductive material layer; wherein the first photoresist layer comprises a plurality of first openings spaced apart along a first direction, and the first openings expose the first conductive material layer;

[0023] Etching the first conductive material layer according to the patterned first photoresist layer to form a plurality of first conductive portions;

[0024] The forming of a second electrode structure on the light absorbing layer comprises:

[0025] forming a second conductive material layer covering the light absorbing layer;

[0026] Forming a patterned second photoresist layer on the second conductive material layer; wherein the second photoresist layer comprises a plurality of second openings spaced apart along a second direction, and the second openings expose the second conductive material layer;

[0027] The second conductive material layer is etched according to the patterned second photoresist layer to form a plurality of second conductive parts.

[0028] In some embodiments, an orthographic projection of the second opening and an orthographic projection of the first opening at least partially overlap.

[0029] In some embodiments, the orthographic projections of the plurality of second openings and the orthographic projections of the plurality of first openings are alternately arranged along the first direction.

[0030] In the embodiments of the present disclosure, a first electrode structure, a light absorbing layer, and a second electrode structure are stacked in sequence on a substrate; the first electrode structure includes a plurality of first conductive portions spaced apart along a first direction, the first conductive portions are configured to receive a first voltage, so that a first doped region is formed in the light absorbing layer; the second electrode structure includes a plurality of second conductive portions spaced apart along the first direction, the second conductive portions are configured to receive a second voltage, so that a second doped region is formed in the light absorbing layer; since the second doped region and the first doped region have different conductivity types and are at least partially in contact, a PN junction can be formed at the contact interface between the first doped region and the second doped region, so that an energy band bending occurs in the light absorbing layer, and the generated energy band bending will help separate electron-hole pairs, form photocurrent, and realize broadband-light detection.

[0031] Furthermore, compared to silicon-based photodetectors, the photodetector provided by the embodiments of the present disclosure has a simple manufacturing process, is beneficial for reducing process processing time and production costs, and is easy to integrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a cross-sectional view of a photodetector according to an embodiment of the present disclosure;

[0033] Figure 2 is a top view of a photodetector according to an embodiment of the present disclosure;

[0034] Figure 3 is a schematic diagram of an energy band of a photodetector according to an embodiment of the present disclosure;

[0035] Figure 4 is a flow chart of a method for manufacturing a photodetector according to an embodiment of the present disclosure;

[0036] Figure 5 A schematic diagram of a photodetector manufacturing process according to an embodiment of the present disclosure is shown in FIG. Figure 1 ;

[0037] Figure 6 A schematic diagram of a photodetector manufacturing process according to an embodiment of the present disclosure is shown in FIG. Figure 2 ;

[0038] Figure 7 A schematic diagram of a photodetector manufacturing process according to an embodiment of the present disclosure is shown in FIG. Figure 3 ;

[0039] Figure 8 is a top view of a first conductive portion according to an embodiment of the present disclosure;

[0040] Fig. 9 A schematic diagram of a photodetector manufacturing process according to an embodiment of the present disclosure is shown in FIG. Figure 4 ;

[0041] Fig.10 A schematic diagram of a photodetector manufacturing process according to an embodiment of the present disclosure is shown in FIG. Figure 5 ;

[0042] Fig.11 A schematic diagram of a photodetector manufacturing process according to an embodiment of the present disclosure is shown in FIG. Figure 6 ;

[0043] Fig.12 A schematic diagram of a photodetector manufacturing process according to an embodiment of the present disclosure is shown in FIG. Figure 7 . DETAILED DESCRIPTION

[0044] The technical solution of the present disclosure will be further described in detail below in conjunction with the accompanying drawings and embodiments. Although the exemplary implementation methods of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the implementation methods described here. On the contrary, these implementation methods are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0045] The present disclosure is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the present disclosure will become more apparent from the following description and claims. It should be noted that the drawings are in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present disclosure.

[0046] It will be understood that the meaning of “on,” “over,” and “over” of the present disclosure should be interpreted in the broadest manner, so that “on” not only means that it is “on” something with no intervening features or layers (i.e., directly on something), but also includes the meaning that it is “on” something with intervening features or layers.

[0047] In the embodiments of the present disclosure, the terms "first", "second", "third", etc. are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0048] In the disclosed embodiments, the term "layer" refers to a material portion including an area having a thickness. A layer may extend over the entirety of a lower or upper structure, or may have an extent less than the extent of a lower or upper structure. In addition, a layer may be an area of ​​a homogeneous or inhomogeneous continuous structure having a thickness less than the thickness of a continuous structure. For example, a layer may be located between the top and bottom surfaces of a continuous structure, or a layer may be between any horizontal faces at the top and bottom surfaces of a continuous structure. A layer may extend horizontally, vertically, and / or along an inclined surface. A layer may include multiple sublayers.

[0049] It should be noted that the technical solutions described in the embodiments of the present disclosure can be arbitrarily combined without conflict.

[0050] Silicon-based photodetectors are limited in detecting wider wavelengths (e.g., wavelengths greater than 980 nanometers) because they respond in the visible light range (400 nanometers to 780 nanometers). In addition, the manufacturing process of silicon-based photodetectors is complex and time-consuming, for example, doping and etching of high-aspect-ratio contact holes are required.

[0051] By applying two-dimensional layered materials (e.g., graphene, etc.), wavelengths from visible light to infrared can be detected. In addition, due to the nano-nature of graphene, not only can traditional silicon-based semiconductor manufacturing methods be applied, but also the recipe process time (RPT) and the complexity of the manufacturing process can be minimized. Therefore, graphene-based photodetectors show good application prospects.

[0052] However, due to the zero bandgap property of graphene, the electron-hole pairs generated by the absorbed photons will quickly recombine, resulting in zero photocurrent, which limits the application of graphene in the field of light detection.

[0053] In view of this, an embodiment of the present disclosure provides a photodetector and a method for manufacturing the same.

[0054] Figure 1is a cross-sectional view of a photodetector 100 according to an embodiment of the present disclosure; Figure 2 is a top view of a photodetector 100 according to an embodiment of the present disclosure; Figure 3 is a schematic diagram of an energy band of a photodetector 100 according to an embodiment of the present disclosure. Figure 1 , Figure 2 and Figure 3 The photodetector 100 provided in the embodiment of the present disclosure is further described.

[0055] Reference Figure 1 As shown, the photodetector 100 includes: a substrate 101; a first electrode structure 110, a light absorbing layer 130 and a second electrode structure 120 stacked on the substrate 101 in sequence. The material of the substrate 101 includes: silicon, silicon nitride or a transparent material. For example, the substrate 101 can be quartz, glass or indium tin oxide. The material of the light absorbing layer 130 includes: at least one of graphene, molybdenum disulfide, black phosphorus, perovskite or quantum dot materials.

[0056] Reference Figure 2 As shown, the first electrode structure 110 includes a plurality of first conductive portions 111 spaced apart along a first direction; the first conductive portions 111 extend along a second direction; wherein the first conductive portions 111 are configured to receive a first voltage so that a first doped region is formed in the light absorbing layer 130; the second direction and the first direction are parallel to the plane where the substrate 101 is located, and the second direction and the first direction intersect; the second electrode structure 120 includes a plurality of second conductive portions 121 spaced apart along the first direction, and the second conductive portions 121 extend along a second direction; wherein the second conductive portions 121 are configured to receive a second voltage so that a second doped region is formed in the light absorbing layer 130; the second voltage is different from the first voltage; the second doped region and the first doped region have different conductivity types and are at least partially in contact.

[0057] In some embodiments, by applying a first voltage to the first conductive portion 111 and a second voltage to the second conductive portion 121, the concentration of carriers in the light absorbing layer 130 may be changed, thereby achieving doping of the light absorbing layer 130. For example, a P-type doping region and an N-type doping region that are at least partially in contact are formed, thereby forming a PN junction in the light absorbing layer 130.

[0058] Taking the light absorption layer 130 as graphene as an example, by applying a negative voltage to the first conductive part 111, a P-type doped region can be formed in the graphene adjacent to the first conductive part 111; by applying a positive voltage to the second conductive part 121, an N-type doped region can be formed in the graphene adjacent to the second conductive part 121; at least part of the P-type doped region is in contact with the N-type doped region, and a PN junction is formed at the contact interface between the P-type doped region and the N-type doped region, so that the graphene generates energy band bending. The energy band diagram of graphene is shown in FIG. Figure 3 When light is irradiated, the resulting band bending will help separate electron-hole pairs and form photocurrent; and because graphene can detect wavelengths from visible light to infrared, broadband light detection can be achieved.

[0059] In other embodiments, a positive voltage may be applied to the first conductive portion 111, and a negative voltage may be applied to the second conductive portion 121, so that the graphene generates energy band bending. It is understood that the first voltage includes a positive voltage or a negative voltage, the second voltage includes a negative voltage or a positive voltage; the first doped region includes an N-type doped region or a P-type doped region, and the second doped region includes a P-type doped region or an N-type doped region.

[0060] In some embodiments, the absolute value of the difference between the first voltage and the second voltage is greater than 0 and less than a preset value. For example, the preset value is 1 V. Here, 1 V is only an example to convey the present disclosure to those skilled in the art, and the value of the preset value is not limited thereto.

[0061] In some embodiments, the materials of the first conductive part 111 and the second conductive part 121 include conductive materials, such as graphene, tungsten, copper, aluminum, gold or platinum, etc. In this embodiment, the first conductive part 111 and the second conductive part 121 are both made of graphene as an example.

[0062] In some embodiments, a size of the first conductive portion 111 in the first direction includes 10 nanometers to 20 nanometers; a size of the second conductive portion 121 in the first direction includes 10 nanometers to 20 nanometers.

[0063] It should be noted that the sizes of the first conductive portion 111 and the second conductive portion 121 in the first direction may be the same or different; the sizes of at least two of the multiple first conductive portions in the first direction may be the same or different; the sizes of at least two of the multiple second conductive portions in the first direction may be the same or different, and the present disclosure has no special restrictions on this.

[0064] In some embodiments, the spacing between two adjacent first conductive parts 111 is 50 nanometers to 100 nanometers; the spacing between two adjacent second conductive parts 121 is 50 nanometers to 100 nanometers. It should be noted that the spacing between two adjacent first conductive parts and the spacing between two adjacent second conductive parts can be the same or different, and there is no special limitation in the present disclosure.

[0065] In some embodiments, the second doped region partially contacts the first doped region. In other embodiments, the second doped region completely contacts the first doped region.

[0066] It should be noted that the first direction, the second direction and the third direction used in the present disclosure are respectively represented as the y direction, the x direction and the z direction; the first direction and the second direction are parallel to the plane where the substrate is located, and the third direction is perpendicular to the plane where the substrate is located; the first direction and the second direction intersect, and the angle between the first direction and the second direction includes an acute angle, a right angle or an obtuse angle, which will not be described in detail hereinafter. In this example, the angle between the first direction and the second direction is a right angle.

[0067] In the embodiments of the present disclosure, a first electrode structure, a light absorbing layer, and a second electrode structure are stacked in sequence on a substrate; the first electrode structure includes a plurality of first conductive portions spaced apart along a first direction, the first conductive portions are configured to receive a first voltage, so that a first doped region is formed in the light absorbing layer; the second electrode structure includes a plurality of second conductive portions spaced apart along the first direction, the second conductive portions are configured to receive a second voltage, so that a second doped region is formed in the light absorbing layer; since the second doped region and the first doped region have different conductivity types and are at least partially in contact, a PN junction can be formed at the contact interface between the first doped region and the second doped region, so that an energy band bending occurs in the light absorbing layer, and the generated energy band bending will help separate electron-hole pairs, form photocurrent, and realize broadband-light detection.

[0068] Furthermore, compared to silicon-based photodetectors, the photodetector provided by the embodiments of the present disclosure has a simple manufacturing process, is beneficial for reducing process processing time and production costs, and is easy to integrate.

[0069] In some embodiments, the orthographic projection of the second conductive portion 121 at least partially overlaps with the orthographic projection of the first conductive portion 111. It can be understood that when the orthographic projection of the second conductive portion 121 partially overlaps with the orthographic projection of the first conductive portion 111, in the xy plane, the orthographic projection of the second conductive portion 121 covers part of the orthographic projection of the first conductive portion 111; when the orthographic projection of the second conductive portion 121 completely overlaps with the orthographic projection of the first conductive portion 111, in the xy plane, the orthographic projection of the second conductive portion 121 covers the orthographic projection of the first conductive portion 111, that is, the orthographic projection of the second conductive portion 121 and the orthographic projection of the first conductive portion 111 coincide.

[0070] In some embodiments, in combination Figure 2 As shown, the orthographic projections of the plurality of second conductive portions 121 and the orthographic projections of the plurality of first conductive portions 111 are alternately arranged along the first direction.

[0071] In some embodiments, reference Figure 1 and Figure 2As shown, the first electrode structure 110 also includes a third conductive portion 112 extending along the first direction; the second electrode structure 120 also includes a fourth conductive portion 122 extending along the first direction; wherein the third conductive portion 112 and the fourth conductive portion 122 are respectively located on two opposite sides of the light absorbing layer 130 along the second direction; one end of the first conductive portion 111 away from the fourth conductive portion 122 is connected to the third conductive portion 112, and one end of the second conductive portion 121 away from the third conductive portion 112 is connected to the fourth conductive portion 122.

[0072] The third conductive portion 112 is connected to the plurality of first conductive portions 111, and the first voltage can be applied to the plurality of first conductive portions 111 respectively through the third conductive portion 112. Here, the third conductive portion 112 extending along the first direction and the plurality of first conductive portions 111 extending along the second direction can constitute a "interdigitated" first electrode structure 110.

[0073] Similarly, the fourth conductive portion 122 is connected to the plurality of second conductive portions 121, and the second voltage can be applied to the plurality of second conductive portions 121 respectively through the fourth conductive portion 122. Here, the fourth conductive portion 122 extending along the first direction and the plurality of second conductive portions 121 extending along the second direction can constitute a "interdigitated" second electrode structure 120.

[0074] In some embodiments, the material of the third conductive portion 112 and the fourth conductive portion 122 includes a conductive material, such as titanium, tungsten, copper, aluminum, gold, platinum, or the like.

[0075] In the embodiment of the present disclosure, by respectively arranging the third conductive part and the fourth conductive part on the two sides opposite to each other along the second direction of the light absorbing layer, a plurality of first conductive parts can be led out through the third conductive part, and a plurality of second conductive parts can be led out through the fourth conductive part, which is helpful to reduce the difficulty of manufacturing the photodetector; and by arranging a "forked finger-shaped" electrode structure, it is helpful to increase the light response area of ​​the light absorbing layer, thereby increasing the photocurrent.

[0076] In some embodiments, reference Figure 2 As shown, the photodetector 100 further includes: a first contact electrode 151 and a second contact electrode 152 ; wherein the first contact electrode 151 and the second contact electrode 152 are respectively located at two opposite sides of the light absorbing layer 130 along the first direction and connected to the light absorbing layer 130 .

[0077] The materials of the first contact electrode 151 and the second contact electrode 152 include conductive materials, such as titanium, tungsten, copper, aluminum, gold or platinum. A bias voltage can be applied to the light absorbing layer 130 through the first contact electrode 151 and the second contact electrode 152. Under the action of the bias voltage, the separated electron-hole pairs move in a directional manner to form a photocurrent, thereby realizing broadband-light detection. The bias voltage can be 0.1 V. The 0.1 V here is only an example, used to convey the present disclosure to those skilled in the art, and the value of the bias voltage is not limited thereto.

[0078] In some embodiments, the photodetector 100 further includes: a first dielectric layer 141, located between the first electrode structure and the light absorbing layer 130; and a second dielectric layer 142, located between the second electrode structure and the light absorbing layer 130. The material of the first dielectric layer 141 and the second dielectric layer 142 includes a dielectric material, for example, at least one of silicon oxide, silicon nitride, silicon oxynitride or hafnium oxide. In the embodiments of the present disclosure, the first dielectric layer 141 and the second dielectric layer 142 are silicon oxide as an example for description.

[0079] In some embodiments, the photodetector 100 is applied in the field of sensing, for example, lidar, car autonomous driving or laser, etc.

[0080] Based on the above-mentioned photoelectric detector, an embodiment of the present disclosure further provides a method for manufacturing the photoelectric detector.

[0081] Figure 4 is a flow chart of a method for manufacturing a photodetector according to an embodiment of the present disclosure. Figure 4 As shown, the manufacturing method at least comprises the following steps:

[0082] S210: providing a substrate;

[0083] S220: forming a first electrode structure on the substrate; wherein the first electrode structure comprises a plurality of first conductive portions spaced apart along a first direction; the first conductive portions extend along a second direction; the second direction and the first direction are parallel to a plane where the substrate is located, and the second direction and the first direction intersect;

[0084] S230: forming a light absorbing layer on the first electrode structure;

[0085] S240: forming a second electrode structure on the light absorbing layer; wherein the second electrode structure comprises a plurality of second conductive portions spaced apart along a first direction, and the second conductive portions extend along a second direction; the first conductive portion is configured to receive a first voltage so as to form a first doped region in the light absorbing layer; the second conductive portion is configured to receive a second voltage so as to form a second doped region in the light absorbing layer; the second voltage is different from the first voltage; the second doped region and the first doped region have different conductivity types and are at least partially in contact.

[0086] It should be noted that Figure 4 The steps shown in the operation are not exclusive, and other steps may be performed before, after or between any steps in the operation shown; Figure 4 The steps shown in the figure can be adjusted in sequence according to actual needs.

[0087] Figures 5 to 12 FIG. 1 is a schematic diagram of a photoelectric detector manufacturing process according to an embodiment of the present disclosure. Figure 4 , Figures 5 to 12 The method for manufacturing the photodetector provided in the embodiment of the present disclosure is described in detail.

[0088] In step S210, refer to Figure 5 As shown, a substrate 101 is provided. The material of the substrate 101 includes: silicon, silicon nitride or a transparent material. For example, the substrate 101 can be quartz, glass or indium tin oxide.

[0089] In step S220, refer to Figure 6 and Figure 7 As shown, a first electrode structure 110 is formed on a substrate 101; wherein the first electrode structure 110 includes a plurality of first conductive portions 111 spaced apart along a first direction; the first conductive portions 111 extend along a second direction; the second direction and the first direction are parallel to the plane where the substrate 101 is located, and the second direction and the first direction intersect.

[0090] In some embodiments, the above step S220 includes: forming a first conductive material layer 111' covering the substrate, such as Figure 6 As shown; a patterned first photoresist layer (not shown in the figure) is formed on the first conductive material layer 111'; wherein the first photoresist layer includes a plurality of first openings spaced apart along a first direction, and the first openings expose the first conductive material layer; the first conductive material layer 111' is etched according to the patterned first photoresist layer to form a plurality of first conductive portions 111, such as Figure 7 and Figure 8 Here, the plurality of first openings are used to define the formation positions of the plurality of first conductive portions.

[0091] The formation process of the first conductive material layer 111' includes: a transfer process or a thin film deposition process, for example, wet transfer or physical vapor deposition. The material of the first conductive material layer 111' includes a conductive material, for example, graphene, tungsten, copper, aluminum, gold or platinum. In this embodiment, the material of the first conductive material layer 111' is graphene as an example for description.

[0092] In some embodiments, reference Figure 8As shown, the dimension d2 of the first conductive portion 111 in the first direction is 10 to 20 nanometers, and the spacing d3 between two adjacent first conductive portions 111 is 50 to 100 nanometers. The first conductive portion 111 is configured to receive a first voltage to form a first doped region in the subsequently formed light absorbing layer 130.

[0093] In some embodiments, reference Figure 7 As shown, the above step S220 further includes: forming a third conductive portion 112 extending along the first direction on the substrate 101. The third conductive portion 112 is connected to the plurality of first conductive portions 111, and a first voltage can be applied to the plurality of first conductive portions 111 respectively through the third conductive portion 112. Here, the third conductive portion 112 extending along the first direction and the plurality of first conductive portions 111 extending along the second direction can constitute a "forked-finger" first electrode structure 110.

[0094] In some embodiments, a dimension d1 of the third conductive portion 112 in the third direction is comprised between 10 nanometers and 20 nanometers.

[0095] In some embodiments, the above manufacturing method further includes: forming a first dielectric layer 141 covering the substrate and the first electrode structure, such as Fig. 9 The material of the first dielectric layer 141 includes a dielectric material, for example, at least one of silicon oxide, silicon nitride, silicon oxynitride or hafnium oxide. In the embodiment of the present disclosure, the first dielectric layer 141 is silicon oxide as an example for description.

[0096] In some embodiments, the size of the first dielectric layer 141 in the first direction includes 10 nanometers to 30 nanometers. The formation process of the first dielectric layer 141 includes: a thin film deposition process, for example, atomic layer deposition.

[0097] In step S230, refer to Fig.10 As shown, a light absorbing layer 130 is formed on the first electrode structure. The formation process of the light absorbing layer 130 includes: a transfer process or a thin film deposition process. The material of the light absorbing layer 130 includes: at least one of graphene, molybdenum disulfide, black phosphorus, perovskite or quantum dot materials.

[0098] In a specific embodiment, the size W1 of the light absorbing layer 130 in the first direction includes but is not limited to 10 micrometers, and the size W2 of the light absorbing layer 130 in the second direction includes but is not limited to 5 micrometers.

[0099] In some embodiments, the above-mentioned manufacturing method further includes: forming a first contact electrode 151 on one side of the light absorbing layer 130 opposite to the first direction, and the first contact electrode 151 is connected to the light absorbing layer 130; forming a second contact electrode 152 on the other side of the light absorbing layer 130 opposite to the first direction, and the second contact electrode 152 is connected to the light absorbing layer 130.

[0100] The formation process of the first contact electrode 151 and the second contact electrode 152 includes but is not limited to evaporation. The material of the first contact electrode 151 and the second contact electrode 152 includes a conductive material, such as titanium, tungsten, copper, aluminum, gold or platinum.

[0101] In some embodiments, the above manufacturing method further includes: forming a second dielectric layer 142 covering the light absorbing layer, such as Fig.11 The material of the second dielectric layer 142 includes a dielectric material, for example, at least one of silicon oxide, silicon nitride, silicon oxynitride or hafnium oxide. In the embodiment of the present disclosure, the second dielectric layer 142 is described as silicon oxide.

[0102] In some embodiments, the size of the second dielectric layer 142 in the first direction is 10 nanometers to 30 nanometers. The formation process of the second dielectric layer 142 includes: a thin film deposition process, for example, atomic layer deposition.

[0103] In step S240, refer to Fig.12 As shown, a second electrode structure 120 is formed on the light absorbing layer; wherein the second electrode structure 120 includes a plurality of second conductive portions 121 spaced apart along a first direction, and the second conductive portions 121 extend along a second direction; the second conductive portions 121 are configured to receive a second voltage so as to form a second doped region in the light absorbing layer 130; the second voltage is different from the first voltage; the second doped region and the first doped region have different conductivity types and are at least partially in contact.

[0104] It should be emphasized that an insulating dielectric layer is further disposed between the plurality of second conductive parts 121 and the first contact electrode 151 and between the plurality of second conductive parts 121 and the second contact electrode 152 , which is not shown in the figure for the sake of illustration.

[0105] In some embodiments, the above step S240 includes: forming a second conductive material layer covering the light absorbing layer 130; forming a patterned second photoresist layer on the second conductive material layer; wherein the second photoresist layer includes a plurality of second openings spaced apart along the second direction, and the second openings expose the second conductive material layer; etching the second conductive material layer according to the patterned second photoresist layer to form a plurality of second conductive portions 121. Here, the plurality of second openings are used to define the formation positions of the plurality of second conductive portions. The formation process of the plurality of second conductive portions can refer to the plurality of first conductive portions, and will not be repeated here.

[0106] In some embodiments, an orthographic projection of the second opening and an orthographic projection of the first opening at least partially overlap.

[0107] In some embodiments, the orthographic projections of the plurality of second openings and the orthographic projections of the plurality of first openings are alternately arranged along the first direction.

[0108] The formation process of the second conductive material layer includes: a transfer process or a thin film deposition process, for example, wet transfer or physical vapor deposition. The material of the second conductive material layer includes a conductive material, for example, graphene, tungsten, copper, aluminum, gold or platinum. In this embodiment, the material of the second conductive material layer is graphene as an example for description.

[0109] In some embodiments, reference Fig.12 As shown, the size of the second conductive portion 121 in the first direction is 10 nanometers to 20 nanometers; and the distance between two adjacent second conductive portions 121 is 50 nanometers to 100 nanometers.

[0110] In some embodiments, reference Fig.12 As shown, the above step S240 also includes: forming a fourth conductive portion 122 extending along the first direction on the light absorbing layer; wherein the third conductive portion and the fourth conductive portion are respectively located on two opposite sides of the light absorbing layer along the second direction; one end of the first conductive portion away from the fourth conductive portion is connected to the third conductive portion, and one end of the second conductive portion away from the third conductive portion is connected to the fourth conductive portion.

[0111] In the embodiment of the present disclosure, by arranging a first contact electrode and a second contact electrode on opposite sides of the light absorbing layer along a first direction, and arranging a third conductive portion and a fourth conductive portion on opposite sides of the light absorbing layer along a second direction, the layout of the photodetector can be optimized, which is beneficial to reducing the planar size of the photodetector and improving the integration.

[0112] The above is only a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A photoelectric detector, characterized in that: include: substrate; A first electrode structure, a light absorbing layer, and a second electrode structure stacked sequentially on the substrate; The first electrode structure comprises a plurality of first conductive portions spaced apart along a first direction; the first conductive portions extend along a second direction; wherein the first conductive portions are configured to receive a first voltage so as to form a first doped region in the light absorbing layer; the second direction and the first direction are parallel to the plane where the substrate is located, and the second direction and the first direction intersect; The second electrode structure includes a plurality of second conductive portions spaced apart along the first direction, and the second conductive portions extend along the second direction; wherein the second conductive portions are configured to receive a second voltage so as to form a second doped region in the light absorbing layer; the second voltage is different from the first voltage; and the second doped region and the first doped region have different conductivity types and are at least partially in contact.

2. The photodetector according to claim 1, characterized in that: The orthographic projection of the second conductive portion and the orthographic projection of the first conductive portion at least partially overlap.

3. The photodetector according to claim 1, characterized in that: The orthographic projections of the plurality of second conductive portions and the orthographic projections of the plurality of first conductive portions are alternately arranged along the first direction.

4. The photodetector according to claim 1, characterized in that: The first electrode structure further includes a third conductive portion extending along the first direction; the second electrode structure further includes a fourth conductive portion extending along the first direction; Among them, the third conductive part and the fourth conductive part are respectively located on two opposite sides of the light absorbing layer along the second direction; one end of the first conductive part away from the fourth conductive part is connected to the third conductive part, and one end of the second conductive part away from the third conductive part is connected to the fourth conductive part.

5. The photodetector according to claim 1 or 4, characterized in that: The photodetector further includes: a first contact electrode and a second contact electrode; wherein the first contact electrode and the second contact electrode are respectively located at two opposite sides of the light absorbing layer along the first direction and connected to the light absorbing layer.

6. The photodetector according to claim 1, characterized in that: The material of the light absorbing layer includes at least one of graphene, molybdenum disulfide, black phosphorus, perovskite or quantum dot materials.

7. A method for manufacturing a photoelectric detector, characterized in that: include: providing a substrate; A first electrode structure is formed on the substrate; wherein the first electrode structure comprises a plurality of first conductive portions spaced apart along a first direction; the first conductive portions extend along a second direction; the second direction and the first direction are parallel to the plane where the substrate is located, and the second direction and the first direction intersect; forming a light absorbing layer on the first electrode structure; A second electrode structure is formed on the light absorbing layer; wherein the second electrode structure includes a plurality of second conductive portions spaced apart along the first direction, and the second conductive portions extend along the second direction; the first conductive portion is configured to receive a first voltage so as to form a first doped region in the light absorbing layer; the second conductive portion is configured to receive a second voltage so as to form a second doped region in the light absorbing layer; the second voltage is different from the first voltage; the second doped region and the first doped region have different conductivity types and are at least partially in contact.

8. The method according to claim 7, characterized in that: The step of forming a first electrode structure on the substrate comprises: forming a first conductive material layer covering the substrate; Forming a patterned first photoresist layer on the first conductive material layer; wherein the first photoresist layer comprises a plurality of first openings spaced apart along a first direction, and the first openings expose the first conductive material layer; Etching the first conductive material layer according to the patterned first photoresist layer to form a plurality of first conductive parts; The forming of a second electrode structure on the light absorbing layer comprises: forming a second conductive material layer covering the light absorbing layer; A patterned second photoresist layer is formed on the second conductive material layer; wherein the second photoresist layer includes a plurality of second openings spaced apart along a second direction, and the second openings expose the second conductive portions.

9. The manufacturing method according to claim 8, characterized in that: The orthographic projection of the second opening and the orthographic projection of the first opening at least partially overlap.

10. The manufacturing method according to claim 8, characterized in that: The orthographic projections of the plurality of second openings and the orthographic projections of the plurality of first openings are alternately arranged along the first direction.

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