Display substrate, manufacturing method thereof and display device

Abstract

The display substrate, the manufacturing method thereof and the display device provided by the present disclosure comprise: a substrate substrate; a plurality of light emitting devices arranged in an array on the substrate substrate; a plurality of drive transistors located between the layer where the plurality of light emitting devices are located and the substrate substrate, the plurality of drive transistors being electrically connected with the plurality of light emitting devices; and a plurality of photosensitive transistors arranged in the same layer as the plurality of drive transistors, and each photosensitive transistor being located at least part of the gap of each drive transistor, the photosensitive transistor being used for collecting reflected light of the lines.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and in particular to a display substrate, a method for manufacturing the substrate, and a display device. Background Technology

[0002] With the rapid development of the information industry, biometric technology has been increasingly widely used. In particular, because different users have different fingerprints, it facilitates user identification; therefore, fingerprint recognition has become a standard feature on mobile phones. Fingerprint recognition technology is divided into under-display fingerprint recognition and in-cell fingerprint recognition. Under-display fingerprint recognition is achieved by attaching the fingerprint recognition module under the display screen, while in-cell fingerprint recognition integrates the photosensitive device (sensor) directly into the display screen, thus allowing for thinner and lighter phones. As flagship phones gradually move towards curved and foldable screens, organic light-emitting diode (OLED) displays have become the choice for most flagship models. Therefore, OLED in-screen fingerprint recognition technology is an important research direction for future mobile phone unlocking. Summary of the Invention

[0003] This disclosure provides a display substrate, a method for manufacturing the same, and a display device to reduce the number of masking processes for in-screen fingerprint recognition, thereby reducing costs and increasing production capacity.

[0004] Therefore, the display substrate provided in this embodiment includes:

[0005] Substrate;

[0006] Multiple light-emitting devices are arranged in an array on the substrate.

[0007] Multiple driving transistors are located between the layer containing the multiple light-emitting devices and the substrate, and the multiple driving transistors are electrically connected to the multiple light-emitting devices;

[0008] Multiple phototransistors are disposed on the same layer as the multiple driving transistors, and each phototransistor is located at at least a portion of the gap between the driving transistors. The phototransistors are used to collect reflected light from the texture.

[0009] In some embodiments, in the display substrate provided in the present disclosure, the active layer of the phototransistor is located between the gate layer of the phototransistor and the substrate.

[0010] The gate of the phototransistor includes a first metal portion, each of the first metal portions including at least one first light-transmitting hole, the orthogonal projection of the at least one first light-transmitting hole on the substrate being located within the orthogonal projection of the channel region of the phototransistor on the substrate.

[0011] In some embodiments, in the display substrate provided in the present disclosure, the gate of the phototransistor further includes a first transparent conductive portion, the first transparent conductive portion being located between the layer containing the first metal portion and the substrate, and the orthogonal projection of the first transparent conductive portion on the substrate substantially coincides with the orthogonal projection of the first metal portion on the substrate.

[0012] In some embodiments, in the display substrate provided in the present disclosure, the gate of the driving transistor includes a second metal portion, and the second metal portion is disposed in the same layer as the first metal portion.

[0013] In some embodiments, in the display substrate provided in the present disclosure, the gate of the driving transistor further includes a second transparent conductive portion, and the second transparent conductive portion is disposed in the same layer as the first transparent conductive portion.

[0014] In some embodiments, in the display substrate provided in the present disclosure, each of the first metal portions includes: one first light-transmitting hole, two first light-transmitting holes arranged in a row direction, two first light-transmitting holes arranged in a column direction, four first light-transmitting holes arranged in an array, or four first light-transmitting holes arranged in a rhombus.

[0015] In some embodiments, the display substrate provided in this disclosure further includes at least one light-shielding layer, wherein the at least one light-shielding layer is located on the side of the active layer of the phototransistor away from the substrate.

[0016] Each of the light-shielding layers includes a plurality of second light-transmitting holes, each of which corresponds to a first light-transmitting hole, and the orthographic projection of the second light-transmitting hole on the substrate overlaps with the orthographic projection of the corresponding first light-transmitting hole on the substrate.

[0017] In some embodiments, the display substrate provided in this disclosure further includes a black matrix, which is located on the side of the layer where the plurality of light-emitting devices are located away from the substrate, and the orthographic projection of the black matrix on the substrate is located within the orthographic projection of the gap between each of the light-emitting devices on the substrate.

[0018] The at least one light-shielding layer shares a film layer with at least one of the black matrix, the anode of the light-emitting device, and the source / drain of the phototransistor.

[0019] In some embodiments, in the display substrate provided in the present disclosure, both the phototransistor and the driving transistor are low-temperature polycrystalline silicon transistors.

[0020] Based on the same inventive concept, this disclosure provides a display device including the display substrate provided in the above-described embodiments.

[0021] Based on the same inventive concept, this disclosure provides a method for manufacturing the above-mentioned display substrate, including:

[0022] Provide a substrate;

[0023] A plurality of driving transistors are formed on the substrate, and a plurality of phototransistors are formed at at least a portion of the gaps between each driving transistor, the phototransistors being used to collect reflected light from the texture.

[0024] Multiple light-emitting devices are formed on the layer containing the multiple driving transistors, wherein the multiple light-emitting devices are electrically connected to the multiple driving transistors.

[0025] In some embodiments, in the fabrication method provided in this disclosure, a plurality of driving transistors are formed on the substrate, and a plurality of phototransistors are formed at at least a portion of the gaps between each driving transistor, specifically including:

[0026] A plurality of first low-temperature polycrystalline silicon active layers and a plurality of second low-temperature polycrystalline silicon active layers are formed on the substrate, wherein each of the first low-temperature polycrystalline silicon active layers is located at at least a portion of the gap between each of the second low-temperature polycrystalline silicon active layers.

[0027] A transparent conductive layer and a metal layer are sequentially formed on the plurality of first low-temperature polycrystalline silicon active layers and the plurality of second low-temperature polycrystalline silicon active layers;

[0028] The metal layer and the transparent conductive layer are etched to form a first transparent conductive portion and a first metal portion located above each of the first low-temperature polysilicon active layers, and a second transparent conductive portion and a second metal portion located above each of the second low-temperature polysilicon active layers;

[0029] At least one first light-transmitting hole is formed in each of the first metal portions;

[0030] Multiple first source / drain electrodes are formed on each of the first metal portions, and multiple second source / drain electrodes are formed on each of the second metal portions. The first source / drain electrodes are electrically connected to the first low-temperature polysilicon active layer in a one-to-one correspondence, and the second source / drain electrodes are electrically connected to the second low-temperature polysilicon active layer in a one-to-one correspondence.

[0031] The first low-temperature polycrystalline silicon active layer, the first transparent conductive portion and the first metal portion stacked together, and the first source / drain electrode constitute a phototransistor, and the second low-temperature polycrystalline silicon active layer, the second transparent conductive portion and the second metal portion stacked together, and the second source / drain electrode constitute a driving transistor.

[0032] In some embodiments, in the fabrication method provided in this disclosure, a plurality of driving transistors are formed on the substrate, and a plurality of phototransistors are formed at at least a portion of the gaps between each driving transistor, specifically including:

[0033] A plurality of first low-temperature polycrystalline silicon active layers and a plurality of second low-temperature polycrystalline silicon active layers are formed on the substrate, wherein each of the first low-temperature polycrystalline silicon active layers is located at at least a portion of the gap between each of the second low-temperature polycrystalline silicon active layers.

[0034] A transparent conductive layer is formed on the plurality of first low-temperature polysilicon active layers and the plurality of second low-temperature polysilicon active layers, and the transparent conductive layer is etched to form a first transparent conductive portion located above each of the first low-temperature polysilicon active layers;

[0035] A metal layer is formed on the layer containing the first transparent conductive portion, and the metal layer is etched to form a first metal portion above each of the first transparent conductive portions and a second metal portion above each of the second low-temperature polycrystalline silicon active layers; wherein each first metal portion includes at least one first light-transmitting hole;

[0036] Multiple first source / drain electrodes are formed on each of the first metal portions, and multiple second source / drain electrodes are formed on each of the second metal portions. The first source / drain electrodes are electrically connected to the first low-temperature polysilicon active layer in a one-to-one correspondence, and the second source / drain electrodes are electrically connected to the second low-temperature polysilicon active layer in a one-to-one correspondence.

[0037] The first low-temperature polycrystalline silicon active layer, the first transparent conductive portion and the first metal portion stacked together, and the first source / drain electrode constitute a phototransistor, and the second low-temperature polycrystalline silicon active layer, the second metal portion, and the second source / drain electrode constitute a driving transistor.

[0038] The beneficial effects of this disclosure are as follows:

[0039] The display substrate, its fabrication method, and display device provided in this disclosure include: a substrate; multiple light-emitting devices arranged in an array on the substrate; multiple driving transistors located between the layer containing the multiple light-emitting devices and the substrate, and electrically connected to the multiple light-emitting devices; and multiple phototransistors disposed on the same layer as the multiple driving transistors, with each phototransistor located at least a portion of the gap between each driving transistor, and the phototransistors being used to collect reflected light from patterns. By using phototransistors disposed on the same layer as the driving transistors to collect reflected light from patterns (e.g., fingerprints) for pattern recognition, good compatibility with the manufacturing process of the driving transistors is achieved, avoiding the separate fabrication of photosensitive devices, thereby reducing the number of masking operations, lowering costs, and increasing production capacity. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the structure of a display substrate provided in an embodiment of this disclosure;

[0041] Figure 2 For along Figure 1 A schematic diagram of a cross-sectional structure of the Middle I-II line;

[0042] Figure 3 For along Figure 1 Another cross-sectional structural diagram of the Middle I-II line;

[0043] Figure 4 For along Figure 1 Another cross-sectional structural diagram of the Middle I-II line;

[0044] Figure 5 An arrangement diagram of the first light-transmitting hole on the first metal part provided in an embodiment of this disclosure;

[0045] Figure 6 Another arrangement of the first light-transmitting hole on the first metal part provided in the embodiments of this disclosure;

[0046] Figure 7 Another arrangement of the first light-transmitting hole on the first metal part provided in the embodiments of this disclosure;

[0047] Figure 8 Another arrangement of the first light-transmitting hole on the first metal part provided in the embodiments of this disclosure;

[0048] Figure 9 Another arrangement of the first light-transmitting hole on the first metal part provided in the embodiments of this disclosure;

[0049] Figure 10 For along Figure 1 Another cross-sectional structural diagram of the Middle I-II line;

[0050] Figure 11 For along Figure 1 Another cross-sectional structural diagram of the Middle I-II line;

[0051] Figure 12 A flowchart illustrating a method for manufacturing a display substrate according to an embodiment of this disclosure. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. It should be noted that the dimensions and shapes of the figures in the drawings do not reflect actual proportions and are only intended to illustrate the content of this disclosure. Furthermore, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout the drawings.

[0053] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure and the claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as “inner,” “outer,” “upper,” and “lower” are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0054] The photosensitive device in the related technology includes a stacked bottom electrode (SD2), an N-type semiconductor layer, an I-type semiconductor layer (also known as an intrinsic semiconductor layer), a P-type semiconductor layer, and a top electrode (ITO). This structure of photosensitive device has a very sensitive light response capability. When integrating the above-mentioned photosensitive device into an OLED screen, five masking processes need to be added to the existing OLED screen manufacturing process. These processes are used to fabricate the insulating layer (PVX1 & PVX2) between the photosensitive device and the driving circuit layer, the first planarization layer (PLN1), the bottom electrode (SD2), the top electrode (ITO), and the protective layer covering the top electrode (ITO). Furthermore, the same masking process is used to fabricate the top electrode (ITO), the N-type semiconductor layer, the I-type semiconductor layer (also known as an intrinsic semiconductor layer), and the P-type semiconductor layer. Therefore, integrating a photosensitive device into an OLED screen for fingerprint recognition in this related technology requires introducing a large number of masking processes, resulting in higher costs and a significant impact on production capacity.

[0055] To address the aforementioned technical problems in related technologies, this disclosure provides a display substrate, such as... Figures 1 to 3 As shown, it includes:

[0056] Substrate 101;

[0057] Multiple light-emitting devices 102 are arranged in an array on a substrate 101. Each light-emitting device 102 may include an anode 1021, a light-emitting functional layer 1022, and a cathode 1023 stacked together. The light-emitting functional layer 1022 includes, but is not limited to, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting material layer, a hole blocking layer, a hole transport layer, and an electron injection layer. The light-emitting devices 102 may include red light-emitting devices R, green light-emitting devices G, and blue light-emitting devices B, etc.

[0058] Multiple driving transistors 103 are located between the layer containing multiple light-emitting devices 102 and the substrate 101, and the multiple driving transistors 103 are electrically connected to the multiple light-emitting devices 102; optionally, the driving transistors 103 and the light-emitting devices 102 are electrically connected in a one-to-one correspondence.

[0059] Multiple phototransistors 104 are disposed on the same layer as multiple driving transistors 103, and each phototransistor 104 is located at least part of the gap between each driving transistor 103. The phototransistors 104 are used to collect reflected light from patterns (e.g., fingerprints). Optionally, the phototransistors 104 can be located in the row gaps between each driving transistor 103. The specific position can be set according to the actual required fingerprint recognition resolution. For example, the higher the resolution, the more phototransistors 104 need to be set, and the more gaps they occupy between each driving transistor 103.

[0060] It should be noted that, in this disclosure, "same-layer setup" refers to a layer structure formed using the same film deposition process to create a film layer for a specific pattern, and then using the same mask to form a single patterning process. That is, one patterning process corresponds to one mask (also called a photomask). Depending on the specific pattern, a single patterning process may include multiple exposure, development, or etching processes. The specific pattern in the formed layer structure can be continuous or discontinuous; these specific patterns may be at the same height or have the same thickness, or they may be at different heights or have different thicknesses.

[0061] In the display substrate provided in the embodiments of this disclosure, by using a photosensitive transistor 104 disposed on the same layer as the driving transistor 103 to collect the reflected light of the texture (e.g., fingerprint) for texture recognition, good compatibility with the manufacturing process of the driving transistor 103 in related technologies is achieved, avoiding the separate fabrication of the photosensitive device (Sensor), thereby reducing the number of masking steps, lowering costs, and increasing production capacity.

[0062] In some embodiments, in the display substrate provided in the present disclosure, such as Figures 4 to 9As shown, the active layer P1 of the phototransistor 104 is located between the layer containing the gate G1 of the phototransistor 104 and the substrate 101, that is, the phototransistor 104 is a top-gate transistor, and the gate G1 of the phototransistor 104 may include a first metal portion G. 11 (e.g., the first metal part G) 11 This structure can be composed of stacked titanium metal layers, aluminum metal layers, and titanium metal layers, with each first metal part G 11 It includes at least one first light-transmitting hole H1, and the orthogonal projection of the first light-transmitting hole H1 on the substrate 101 is located within the orthogonal projection of the channel region A of the phototransistor 104 on the substrate 101. The presence of the first light-transmitting hole H1 ensures that the reflected light from the fingerprint can illuminate the channel region A of the phototransistor 104 to generate an electrical signal.

[0063] In some embodiments, in the display substrate provided in the present disclosure, such as Figure 2 and Figure 3 As shown, the gate G1 of the phototransistor 104 may further include a first transparent conductive portion G. 12 (e.g., the first transparent conductive part G) 12 The material can be indium tin oxide (ITO, etc.), and the first transparent conductive part G 12 Located in the first metal part G 11 Between the layer and the substrate 101, the first transparent conductive part G 12 The orthographic projection on the substrate 101 and the first metal part G 11 The orthographic projections on the substrate 101 roughly coincide, meaning that due to limitations in process conditions or the influence of other factors such as measurement, the first transparent conductive part G... 12 The orthographic projection on the substrate 101 and the first metal part G 11 The orthographic projections on the substrate 101 may coincide exactly, or they may deviate slightly (e.g., with a deviation of ±2 μm). Therefore, the first transparent conductive portion G... 12 The orthographic projection on the substrate 101 and the first metal part G 11 The relationship of "approximately coincidence" between the orthographic projections on the substrate 101 is within the protection scope of this disclosure as long as the error is permissible.

[0064] First Metal Section G 11 Having a first light-transmitting hole H1 will make the first metal part G 11 When the gate voltage is applied, the position in channel region A corresponding to the first light-transmitting hole H1 cannot be driven by the gate voltage, affecting the response of channel region A to fingerprint reflected light. This is achieved through the first metal part G... 11 The lower contact is provided with a first transparent conductive part G of similar size. 12 This allows the first transparent conductive part G to be utilized.12 A gate voltage is provided at all locations in the channel region A, thereby improving the sensitivity of the channel region A to the response of fingerprint reflected light.

[0065] In some embodiments, in the display substrate provided in the present disclosure, such as Figures 2 to 4 As shown, the gate G2 of the driving transistor 103 includes a second metal portion G. 21 Second metal part G 21 With the first metal part G 11 The same layer setting saves on masking processes, reduces the number of film layers, lowers production costs, and increases production capacity.

[0066] In some embodiments, in the display substrate provided in the present disclosure, such as Figure 2 As shown, the gate G2 of the driving transistor 103 may further include a second transparent conductive portion G. 22 Second transparent conductive part G 22 With the first transparent conductive part G 12 The same layer setting saves on masking processes, reduces the number of film layers, lowers production costs, and increases production capacity.

[0067] In some embodiments, in the display substrate provided in the present disclosure, such as Figures 5 to 9 As shown, each first metal part G 11 This can include: a first light-transmitting hole H1, two first light-transmitting holes H1 arranged along the row direction X, two first light-transmitting holes H1 arranged along the column direction Y, four first light-transmitting holes H1 arranged in an array, or four first light-transmitting holes H1 arranged in a rhombus (for example, the center lines of the four first light-transmitting holes H1 form a rhombus). Optionally, the row direction X can be the length (L) direction of the channel region A, and the column direction Y can be the width (W) direction of the channel region A. It should be noted that in this disclosure, the first light-transmitting hole H1 is in each first metal part G. 11 The number, arrangement, and position of the items are not limited to... Figures 5 to 9 The embodiment shown. In addition, the first light-transmitting hole H1 can be entirely round, entirely square, or partially round and partially square, etc., without specific limitations. Figures 5 to 9 The via H is used to realize the electrical connection between the active layer P1 of the phototransistor 104 and the source / drain S1 / D1.

[0068] In some embodiments, in the display substrate provided in the present disclosure, such as Figures 2 to 4As shown, it may further include at least one light-shielding layer 105, with all light-shielding layers 105 located on the side of the active layer P1 of the phototransistor 104 away from the substrate 101. Each light-shielding layer 105 includes a plurality of second light-transmitting holes H2, with each second light-transmitting hole H2 corresponding to a first light-transmitting hole H1. The orthographic projection of the second light-transmitting hole H2 onto the substrate 101 overlaps with the orthographic projection of the corresponding first light-transmitting hole H1 onto the substrate 101, thereby forming a collimation structure between the corresponding first light-transmitting holes H1 and H2. This enables the collection of light at small angles (e.g., -10° to 10°), avoids interference from large-angle stray light, and improves the accuracy of fingerprint recognition. In specific implementations, the aperture of the first light-transmitting hole H1 may be smaller than or equal to the aperture of the second light-transmitting hole H2.

[0069] In some embodiments, in the display substrate provided in the present disclosure, such as Figure 10 As shown, it may also include a black matrix 106, which is located on the side of the layer containing the plurality of light-emitting devices 102 away from the substrate 101. The orthographic projection of the black matrix 106 on the substrate 101 lies within the orthographic projection of the gaps between the light-emitting devices 102 on the substrate 101. That is, the black matrix 103 has an opening K at the position corresponding to each light-emitting device 102. The opening K may be filled with a color resist 107 so that the emitted light from each light-emitting device 102 is selectively emitted through the color resist 107, thereby improving color purity and reducing reflection of ambient light.

[0070] In some embodiments, such as Figures 2 to 4 , Figure 10 and Figure 11 As shown, the light-shielding layer 105 provided in this disclosure can share a film layer with at least one of the black matrix 106, the anode 1021 of the light-emitting device 102, and the source / drain S1 / D1 of the phototransistor 104, thereby saving masking processes, reducing the number of film layers, lowering production costs, and increasing production capacity. Specifically, this disclosure uses the example of a single layer of light-shielding layer 105 for illustration. Figures 2 to 4 The diagram shows that the light-shielding layer 105 and the anode 1021 share the same conductive film layer, and the light-shielding layer 105 is disconnected from the adjacent anode 1021 to avoid signal crosstalk on different anodes 1021; for example, in Figure 10 The diagram shows that the light-shielding layer 105 and the black matrix 106 share the same black resin layer. Since no electrical signal is loaded on the black matrix 106, the black matrix 106 and the light-shielding layer 105 can be reused; for example, in... Figure 11 The diagram shows that the light-shielding layer 105 and the source / drain S1 / D1 of the phototransistor 104 share the same conductive film layer, and the light-shielding layer 105 is disconnected from the source / drain S1 / D1 to avoid signal crosstalk on the source / drain S1 / D1.

[0071] It should be understood that there is also an OLED screen in the related technology that does not use color resist 107 and black matrix 106 to reduce the reflection of external ambient light, but uses a circular polarizer for the reduction of reflection. In this case, the light-shielding layer 105 can share a film layer with at least one of the anode 1021 of the light-emitting device 102 and the source / drain S1 / D1 of the phototransistor 104.

[0072] In some embodiments, in the display substrate provided in this disclosure, both the phototransistor 104 and the driving transistor 103 can be low-temperature polysilicon transistors, that is, the active layer material of both is low-temperature polysilicon (Poly-Si). Low-temperature polysilicon transistors have high mobility, low power consumption, and high reliability, which is beneficial for improving the display quality and fingerprint imaging quality.

[0073] In some embodiments, in the display substrate provided in the present disclosure, such as Figures 2 to 4 , Figure 10 and Figure 11 As shown, the substrate may further include: a first buffer layer 108, a first gate insulating layer 109, a second gate insulating layer 110, a gate metal layer 111, an interlayer dielectric layer 112, a first planarization layer 113, a pixel defining layer 114, a support layer 115, an encapsulation layer 116, a second buffer layer 117, a second planarization layer 118, a protective cover plate 119, and a read transistor 120, etc. The structure of the read transistor 120 may be the same as that of the driving transistor 103. The encapsulation layer 116 may include a first inorganic encapsulation layer (CVD1), an organic encapsulation layer (IJP), and a second inorganic encapsulation layer (CVD2) stacked together. Other essential components of the display substrate are understood by those skilled in the art and will not be described in detail here, nor should they be construed as limiting the scope of this disclosure.

[0074] Based on the same inventive concept, this disclosure provides a method for manufacturing the above-mentioned display substrate. Since the principle of this manufacturing method in solving the problem is similar to that of the above-mentioned display substrate in solving the problem, the implementation of the manufacturing method provided in this disclosure can refer to the implementation of the above-mentioned display substrate provided in this disclosure, and repeated details will not be described again.

[0075] Specifically, the method for manufacturing the display substrate provided in the embodiments of this disclosure is as follows: Figure 12 As shown, the following steps may be included:

[0076] S1201, Provide a substrate;

[0077] S1202. A plurality of driving transistors are formed on a substrate, and a plurality of phototransistors are formed at at least a portion of the gaps between each driving transistor. The phototransistors are used to collect reflected light from the texture.

[0078] S1203. Multiple light-emitting devices are formed on the layer containing multiple driving transistors, wherein the multiple light-emitting devices are electrically connected to the multiple driving transistors.

[0079] In some embodiments, in the fabrication method provided in this disclosure, step S1202, which involves forming a plurality of driving transistors on a substrate and forming a plurality of phototransistors at at least a portion of the gaps between each driving transistor, can be implemented in the following two ways:

[0080] The first implementation method includes the following steps:

[0081] Step 1: A plurality of first low-temperature polysilicon active layers (i.e., P1) and a plurality of second low-temperature polysilicon active layers P2 are formed on the substrate 101, wherein each first low-temperature polysilicon active layer (i.e., P1) is located at least a portion of the gaps between each second low-temperature polysilicon active layer P2.

[0082] Step 2: A transparent conductive layer and a metal layer are sequentially formed on multiple first low-temperature polycrystalline silicon active layers (i.e., P1) and multiple second low-temperature polycrystalline silicon active layers P2.

[0083] Step 3: Etch the metal layer and the transparent conductive layer to form the first transparent conductive portion G located above each first low-temperature polysilicon active layer (i.e., P1). 12 and the first metal part G 11 and the second transparent conductive portion G located above each of the second low-temperature polycrystalline silicon active layers P2 22 Second metal part G 21 In some embodiments, the metal layer may be etched first using a dry etching method, and then the transparent conductive layer may be etched using a wet etching method.

[0084] Step 4: In each first metal part G 11 The first metal part G is formed inside. 11 At least one first light-transmitting hole H1 is provided, and the metal portions of other transistors (e.g., drive transistor 103 and read transistor 120) are not etched with vias.

[0085] Step 5: At each of the first metal parts G 11 Multiple first source / drain electrodes (i.e., S1 / D1) are formed on the layer, and simultaneously in each second metal part G 21 Multiple second source / drain electrodes S2 / D2 are formed on the layer. The first source / drain electrode (i.e., S1 / D1) is electrically connected to the first low-temperature polycrystalline silicon active layer (i.e., P1) in a one-to-one correspondence. The second source / drain electrode S2 / D2 is electrically connected to the second low-temperature polycrystalline silicon active layer P2 in a one-to-one correspondence. Among them, the first low-temperature polycrystalline silicon active layer (i.e., P1) and the first transparent conductive part G are stacked together. 12 and the first metal part G11 The phototransistor 104 is composed of a first source / drain electrode (i.e., S1 / D1), a second low-temperature polysilicon active layer P2, and a second transparent conductive portion G stacked on top of each other. 22 Second metal part G 21 The first source / drain (S1 / D1) and the second source / drain (S2 / D2) constitute the driving transistor 103. Specifically, the first source / drain (S1 / D1) and the first low-temperature polysilicon active layer (P1) are connected by... Figures 5 to 9 The via H is electrically connected to the second low-temperature polysilicon active layer P2, which penetrates the first gate insulating layer 109, the second gate insulating layer 110, and the interlayer dielectric layer 112. Similarly, the second source / drain S2 / D2 is also electrically connected to the second low-temperature polysilicon active layer P2 through a via penetrating the first gate insulating layer 109, the second gate insulating layer 110, and the interlayer dielectric layer 112.

[0086] As can be seen from the above, compared with the prior art which completes the fabrication of the gate G2 of the driving transistor 103 through a single masking process, this disclosure adds a masking process for fabricating the first light-transmitting hole H1; however, compared with the five masking processes required for fabricating photosensitive devices, this disclosure reduces four masking processes.

[0087] The second implementation method includes the following steps:

[0088] Step 1: A plurality of first low-temperature polysilicon active layers (i.e., P1) and a plurality of second low-temperature polysilicon active layers P2 are formed on the substrate 101, wherein each first low-temperature polysilicon active layer (i.e., P1) is located at least a portion of the gaps between each second low-temperature polysilicon active layer P2.

[0089] Step 2: A transparent conductive layer is formed on multiple first low-temperature polysilicon active layers (i.e., P1) and multiple second low-temperature polysilicon active layers P2, and the transparent conductive layer is etched to form a first transparent conductive portion G located above each first low-temperature polysilicon active layer (i.e., P1). 12 .

[0090] Step 3: In the first transparent conductive part G 12 A metal layer is formed on the layer in which it is located, and the metal layer is etched to form the first transparent conductive part G located on each layer. 12 The first metal part G above 11 and the second metal portion G located above each of the second low-temperature polycrystalline silicon active layers P2 21 ; wherein, each first metal part G 11 It includes at least one first light-transmitting hole H1.

[0091] Step 4: Form multiple first source / drain electrodes (i.e., S1 / D1) on the layer where each first metal part G11 is located, and simultaneously form multiple first source / drain electrodes (i.e., S1 / D1) on each second metal part G11. 21Multiple second source / drain electrodes S2 / D2 are formed on the layer. The first source / drain electrode (i.e., S1 / D1) is electrically connected to the first low-temperature polycrystalline silicon active layer (i.e., P1) in a one-to-one correspondence. The second source / drain electrode S2 / D2 is electrically connected to the second low-temperature polycrystalline silicon active layer P2 in a one-to-one correspondence. Among them, the first low-temperature polycrystalline silicon active layer (i.e., P1) and the first transparent conductive part G are stacked together. 12 and the first metal part G 11 The phototransistor 104 is composed of a first source / drain electrode (i.e., S1 / D1), a second low-temperature polysilicon active layer P2, and a second metal part G. 21 The first source / drain (S1 / D1) and the second source / drain (S2 / D2) constitute the driving transistor 103. Specifically, the first source / drain (S1 / D1) and the first low-temperature polysilicon active layer (P1) are connected by... Figures 5 to 9 The via H is electrically connected to the second low-temperature polysilicon active layer P2, which penetrates the first gate insulating layer 109, the second gate insulating layer 110, and the interlayer dielectric layer 112. Similarly, the second source / drain S2 / D2 is also electrically connected to the second low-temperature polysilicon active layer P2 through a via penetrating the first gate insulating layer 109, the second gate insulating layer 110, and the interlayer dielectric layer 112.

[0092] As can be seen from the above, compared with the prior art which completes the fabrication of the gate G2 of the driving transistor 103 through a single mask process, this disclosure adds a step to fabricate the first transparent conductive part G. 12 The process involves a masking process and a masking process for creating the first light-transmitting hole H1; however, compared to the five additional masking processes required for fabricating photosensitive devices, this disclosure reduces the number of masking processes by three.

[0093] It should be noted that the fabrication of the light-emitting device 102 and other films in this embodiment is the same as in related technologies, and will not be described in detail here.

[0094] Furthermore, in the fabrication method provided in the embodiments of this disclosure, the patterning processes involved in forming each layer structure may include not only some or all of the processes such as deposition, photoresist coating, masking, exposure, development, etching, and photoresist stripping, but may also include other processes, depending on the actual pattern formed during the fabrication process, and are not limited here. For example, a post-baking process may be included after development and before etching.

[0095] The deposition process can be chemical vapor deposition, plasma-enhanced chemical vapor deposition, or physical vapor deposition, and is not limited here; the mask used in the masking process can be a half-tone mask, a single-slit mask, or a gray-tone mask, and is not limited here; the etching can be dry etching or wet etching, and is not limited here.

[0096] Based on the same inventive concept, this disclosure also provides a display device, including the display substrate described in the embodiments of this disclosure, which can be an OLED display substrate. Since the principle by which this display device solves the problem is similar to that of the display substrate described above, the implementation of this display device can refer to the embodiments of the display substrate described above, and repeated details will not be elaborated upon. Other essential components of the display substrate are those that should be understood by those skilled in the art, and will not be described in detail here, nor should they be construed as limiting this disclosure.

[0097] In some embodiments, the display device provided in this disclosure can be any product or component with display functionality, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, navigator, smartwatch, fitness wristband, or personal digital assistant. The display device provided in this disclosure may also include, but is not limited to, components such as a radio frequency unit, network module, audio output unit, input unit, sensor, display unit, user input unit, interface unit, memory, processor, and power supply. Those skilled in the art will understand that the composition of the above-described display device does not constitute a limitation on the display device; the display device may include more or fewer of the above-described components, or combine certain components, or have different component arrangements.

[0098] Obviously, although preferred embodiments of this disclosure have been described, those skilled in the art can make various modifications and variations to the embodiments of this disclosure without departing from the spirit and scope of the embodiments of this disclosure. Therefore, this disclosure is also intended to include such modifications and variations if they fall within the scope of the claims of this disclosure and their equivalents.

Claims

1. A display substrate, characterized in that, include: Substrate; Multiple light-emitting devices are arranged in an array on the substrate. Multiple driving transistors are located between the layer containing the multiple light-emitting devices and the substrate, and the multiple driving transistors are electrically connected to the multiple light-emitting devices; Multiple phototransistors are disposed on the same layer as the multiple driving transistors, and each phototransistor is located at at least a portion of the gap between each driving transistor. The phototransistors are used to collect reflected light from the texture. The active layer of the phototransistor is located between the gate layer of the phototransistor and the substrate. The gate of the phototransistor includes a first metal portion and a first transparent conductive portion. Each first metal portion includes at least one first light-transmitting hole. The orthogonal projection of the at least one first light-transmitting hole on the substrate is located within the orthogonal projection of the channel region of the phototransistor on the substrate. The first transparent conductive portion is disposed in contact with the first metal portion on the side of the first metal portion facing the substrate, and the orthographic projection of the first transparent conductive portion on the substrate coincides with the orthographic projection of the first metal portion on the substrate.

2. The display substrate as described in claim 1, characterized in that, The gate of the driving transistor includes a second metal portion, which is disposed in the same layer as the first metal portion.

3. The display substrate as described in claim 2, characterized in that, The gate of the driving transistor also includes a second transparent conductive portion, which is disposed in the same layer as the first transparent conductive portion.

4. The display substrate according to any one of claims 1 to 3, characterized in that, Each of the first metal portions includes: one first light-transmitting hole, two first light-transmitting holes arranged in a row direction, two first light-transmitting holes arranged in a column direction, four first light-transmitting holes arranged in an array, or four first light-transmitting holes arranged in a rhombus.

5. The display substrate according to any one of claims 1 to 3, characterized in that, It also includes at least one light-shielding layer, the at least one light-shielding layer being located on the side of the active layer of the phototransistor away from the substrate. Each of the light-shielding layers includes a plurality of second light-transmitting holes, each of which corresponds to a first light-transmitting hole, and the orthographic projection of the second light-transmitting hole on the substrate overlaps with the orthographic projection of the corresponding first light-transmitting hole on the substrate.

6. The display substrate as described in claim 5, characterized in that, It also includes a black matrix, which is located on the side of the layer where the plurality of light-emitting devices are located away from the substrate, and the orthographic projection of the black matrix on the substrate is located within the orthographic projection of the gap between each of the light-emitting devices on the substrate; The at least one light-shielding layer shares a film layer with at least one of the black matrix, the anode of the light-emitting device, and the source / drain of the phototransistor.

7. The display substrate according to any one of claims 1 to 3, 6, characterized in that, Both the phototransistor and the driving transistor are low-temperature polycrystalline silicon transistors.

8. A display device, characterized in that, Includes the display substrate as described in any one of claims 1 to 7.

9. A method for manufacturing a display substrate as described in any one of claims 1 to 7, characterized in that, include: Provide a substrate; A plurality of driving transistors are formed on the substrate, and a plurality of phototransistors are formed at at least a portion of the gaps between each driving transistor, the phototransistors being used to collect reflected light from the texture. Multiple light-emitting devices are formed on the layer containing the multiple driving transistors, wherein the multiple light-emitting devices are electrically connected to the multiple driving transistors.

10. The manufacturing method as described in claim 9, characterized in that, A plurality of driving transistors are formed on the substrate, and a plurality of phototransistors are formed at at least a portion of the gaps between each of the driving transistors, specifically including: A plurality of first low-temperature polycrystalline silicon active layers and a plurality of second low-temperature polycrystalline silicon active layers are formed on the substrate, wherein each of the first low-temperature polycrystalline silicon active layers is located at at least a portion of the gap between each of the second low-temperature polycrystalline silicon active layers. A transparent conductive layer and a metal layer are sequentially formed on the plurality of first low-temperature polycrystalline silicon active layers and the plurality of second low-temperature polycrystalline silicon active layers; The metal layer and the transparent conductive layer are etched to form a first transparent conductive portion and a first metal portion located above each of the first low-temperature polysilicon active layers, and a second transparent conductive portion and a second metal portion located above each of the second low-temperature polysilicon active layers; At least one first light-transmitting hole is formed in each of the first metal portions; Multiple first source / drain electrodes are formed on each of the first metal portions, and multiple second source / drain electrodes are formed on each of the second metal portions. The first source / drain electrodes are electrically connected to the first low-temperature polysilicon active layer in a one-to-one correspondence, and the second source / drain electrodes are electrically connected to the second low-temperature polysilicon active layer in a one-to-one correspondence. The first low-temperature polycrystalline silicon active layer, the first transparent conductive portion and the first metal portion stacked together, and the first source / drain electrode constitute a phototransistor, and the second low-temperature polycrystalline silicon active layer, the second transparent conductive portion and the second metal portion stacked together, and the second source / drain electrode constitute a driving transistor.

11. The manufacturing method as described in claim 9, characterized in that, A plurality of driving transistors are formed on the substrate, and a plurality of phototransistors are formed at at least a portion of the gaps between each of the driving transistors, specifically including: A plurality of first low-temperature polycrystalline silicon active layers and a plurality of second low-temperature polycrystalline silicon active layers are formed on the substrate, wherein each of the first low-temperature polycrystalline silicon active layers is located at at least a portion of the gap between each of the second low-temperature polycrystalline silicon active layers. A transparent conductive layer is formed on the plurality of first low-temperature polysilicon active layers and the plurality of second low-temperature polysilicon active layers, and the transparent conductive layer is etched to form a first transparent conductive portion located above each of the first low-temperature polysilicon active layers; A metal layer is formed on the layer containing the first transparent conductive portion, and the metal layer is etched to form a first metal portion above each of the first transparent conductive portions and a second metal portion above each of the second low-temperature polycrystalline silicon active layers; wherein each first metal portion includes at least one first light-transmitting hole; Multiple first source / drain electrodes are formed on each of the first metal portions, and multiple second source / drain electrodes are formed on each of the second metal portions. The first source / drain electrodes are electrically connected to the first low-temperature polysilicon active layer in a one-to-one correspondence, and the second source / drain electrodes are electrically connected to the second low-temperature polysilicon active layer in a one-to-one correspondence. The first low-temperature polycrystalline silicon active layer, the first transparent conductive portion and the first metal portion stacked together, and the first source / drain electrode constitute a phototransistor, and the second low-temperature polycrystalline silicon active layer, the second metal portion, and the second source / drain electrode constitute a driving transistor.

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