A light emitting transistor and a method for manufacturing the same

Abstract

The present invention discloses a light-emitting transistor and a method for manufacturing the same, wherein the light-emitting transistor comprises a gate, an insulating layer, an electron transport layer, a source metal, an active light-emitting layer, a hole transport layer and a drain metal; the gate is connected to the insulating layer; in the vertical direction, when the upper surface of the active light-emitting layer is connected to the hole transport layer, and the lower surface of the active light-emitting layer is connected to the electron transport layer: the electron transport layer is composed of a first sheet-like thin film semiconductor and a first grid-like semiconductor in close contact in the horizontal direction; the upper surface of the first grid-like semiconductor is connected to the lower surface of the active light-emitting layer; the upper surface of the first sheet-like thin film semiconductor is connected to the lower surface of the source metal; the upper surface of the hole transport layer is connected to the lower surface of the drain metal; the lower surface of the electron transport layer is connected to the upper surface of the insulating layer. The grid-like semiconductor portion of the light-emitting transistor in the embodiment of the present application can effectively reduce the current size of the light-emitting transistor, so that the off-state current is reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a light-emitting transistor and a method for manufacturing the same. Background Art

[0002] The light-emitting transistor combines the switching and amplification characteristics of the transistor and the electroluminescent characteristics of the light-emitting diode, and has great development potential in the field of high-integration display and electrically pumped laser. In the related technology, the channel of the light-emitting transistor with a horizontal structure is relatively long, and it is difficult to make a multi-layer structure, resulting in a slow switching speed of the light-emitting transistor; while the vertical transistor channel length is relatively short, and the channel cannot be closed well, resulting in a relatively large off-state current of the light-emitting transistor, and a large power loss of the transistor in the off state. In addition, an excessively large off-state current will also lead to a low switching ratio of the light-emitting transistor (the switching ratio refers to the ratio of the transistor on-state current to the off-state current), thereby affecting the light-dark contrast when the light-emitting transistor is used for display, resulting in a poor display effect. Summary of the invention

[0003] The present application aims to solve one of the technical problems in the related art at least to a certain extent. To this end, the present application proposes a light-emitting transistor and a manufacturing method thereof, which can effectively reduce the off-state current of the light-emitting transistor, thereby improving the on-off ratio of the transistor.

[0004] In a first aspect, an embodiment of the present application provides a light-emitting transistor, which is a vertical structure, and includes a gate, an insulating layer, an electron transport layer, a source metal, an active light-emitting layer, a hole transport layer and a drain metal; the upper surface of the gate is connected to the lower surface of the insulating layer; in the vertical direction, when the upper surface of the active light-emitting layer is connected to the hole transport layer, and the lower surface of the active light-emitting layer is connected to the electron transport layer: the electron transport layer is composed of a first sheet-like thin film semiconductor and a first grid-like semiconductor in close contact in the horizontal direction; the upper surface of the first grid-like semiconductor is connected to the lower surface of the active light-emitting layer; the upper surface of the first sheet-like thin film semiconductor is connected to the lower surface of the source metal; the The upper surface of the hole transport layer is connected to the lower surface of the drain metal; the lower surface of the electron transport layer is connected to the upper surface of the insulating layer; or, in the vertical direction, when the upper surface of the active light-emitting layer is connected to the lower surface of the electron transport layer, and the lower surface of the active light-emitting layer is connected to the hole transport layer: the hole transport layer is composed of a second sheet-like thin film semiconductor and a second grid-like semiconductor in close contact in the horizontal direction; the upper surface of the second grid-like semiconductor is connected to the lower surface of the active light-emitting layer; the upper surface of the second sheet-like thin film semiconductor is connected to the lower surface of the drain metal; the upper surface of the electron transport layer is connected to the lower surface of the source metal; the lower surface of the hole transport layer is connected to the upper surface of the insulating layer.

[0005] Optionally, the light emitting transistor further includes: a substrate; the substrate material includes one of Si, glass or a flexible substrate; and the substrate is connected to the gate.

[0006] Optionally, the gate includes a first gate and a second gate that are electrically independent of each other; the lower surface of the first gate and the lower surface of the second gate are both connected to the substrate; the upper surface of the first gate and the upper surface of the second gate are both connected to the insulating layer.

[0007] Optionally, the light-emitting transistor also includes an insulating layer, and the gate includes a first gate and a second gate; the lower surface of the first gate is connected to the substrate; the upper surface of the first gate is connected to the lower surface of the insulating layer; the upper surface of the insulating layer is respectively connected to the lower surfaces of the insulating layer and the second gate; the insulating layer and the second gate are in close contact in the horizontal direction; the upper surface of the second gate is covered by the insulating layer; in the vertical direction, the area of ​​the first gate is larger than the area of ​​the second gate.

[0008] Optionally, in the vertical direction, the areas of the sheet-like thin film semiconductor and the grid-like semiconductor are equal, and the area of ​​the sheet-like thin film semiconductor is half the area of ​​the electron transport layer.

[0009] Optionally, the material of the gate includes at least one of Cr / Au, Al, Mo, ITO, and Ti; the insulating layer is an oxidized insulating layer or a polymer insulating layer; the material of the electron transport layer includes at least one of TiO2, TPBi, ZnO, ZnMgO, SnO, and In2O3; the material of the source metal and the drain metal includes at least one of Ag, Al, and Au; the material of the active light-emitting layer includes at least one of organic light-emitting materials, quantum dots, quantum wells, and perovskites; the material of the hole transport layer includes at least one of PEDOT:PSS, CBP, PVK, TFB, CuI, and NiO.

[0010] In a second aspect, an embodiment of the present application provides a method for manufacturing a light-emitting transistor, which is a vertical structure, and the method includes: cleaning and drying a substrate made of glass or a flexible substrate; depositing a gate on the upper surface of the substrate; spin coating or depositing an insulating layer on the upper surface of the gate; depositing an electron transport layer on the upper surface of the insulating layer, wherein the electron transport layer is a sheet-like thin film semiconductor, and half of the sheet-like thin film semiconductor is patterned in the horizontal direction to obtain a grid-like semiconductor; spin coating or depositing an active light-emitting layer on the upper surface of the grid-like semiconductor; depositing a hole transport layer on the upper surface of the active light-emitting layer; in a vacuum environment, evaporating or sputtering a source metal on the upper surface of the sheet-like thin film semiconductor, and evaporating or sputtering a drain metal on the upper surface of the hole transport layer.

[0011] Optionally, after the step of depositing a gate layer on the upper surface of the substrate, the method further comprises: patterning the gate to obtain a first gate and a second gate that are electrically independent of each other;

[0012] Optionally, depositing a gate on the upper surface of the substrate includes: depositing a first gate on the upper surface of the substrate; depositing an insulating layer on the upper surface of the first gate; the upper surface of the insulating layer consists of a first region and a second region; depositing a second gate on the first region; wherein the area of ​​the first gate is greater than the area of ​​the second gate; spin coating or depositing an insulating layer on the upper surface of the gate is specifically: depositing an insulating layer on the second region and the upper surface of the second gate.

[0013] Optionally, the step of cleaning and drying the substrate made of glass or a flexible substrate and depositing a gate on the upper surface of the substrate includes: cleaning and drying the substrate made of Si and using the substrate made of Si as the gate.

[0014] The beneficial effects of the embodiments of the present application are as follows: the light-emitting transistor proposed in the present application includes a gate, an insulating layer, an electron transport layer, a source metal, an active light-emitting layer, a hole transport layer and a drain metal; the gate is connected to the insulating layer; in the vertical direction, when the upper surface of the active light-emitting layer is connected to the hole transport layer, and the lower surface of the active light-emitting layer is connected to the electron transport layer: the electron transport layer is composed of a first sheet-like thin film semiconductor and a first grid-like semiconductor in close contact in the horizontal direction; the upper surface of the first grid-like semiconductor is connected to the lower surface of the active light-emitting layer; the upper surface of the first sheet-like thin film semiconductor is connected to the lower surface of the source metal; the upper surface of the hole transport layer is connected to the lower surface of the drain metal; the lower surface of the electron transport layer is connected to the upper surface of the insulating layer. Alternatively, in the vertical direction, when the upper surface of the active light-emitting layer is connected to the lower surface of the electron transport layer, and the lower surface of the active light-emitting layer is connected to the hole transport layer: the hole transport layer is composed of a second sheet-like thin film semiconductor and a second grid-like semiconductor in close contact in the horizontal direction; the upper surface of the second grid-like semiconductor is connected to the lower surface of the active light-emitting layer; the upper surface of the second sheet-like thin film semiconductor is connected to the lower surface of the drain metal; the upper surface of the electron transport layer is connected to the lower surface of the source metal; the lower surface of the hole transport layer is connected to the upper surface of the insulating layer. Since the conductivity of the grid-structured semiconductor is lower than that of the sheet-like thin film semiconductor, the electron transport layer or the hole transport layer of the light-emitting transistor in the embodiment of the present application is composed of a sheet-like thin film semiconductor and a grid-like semiconductor, and the part of the grid-like semiconductor can effectively reduce the current size of the light-emitting transistor, so that the off-state current is reduced; and the grid-like semiconductor increases the gate's ability to regulate the active light-emitting layer, further improving the transistor's switching ratio, thereby effectively reducing the power loss of the light-emitting transistor, which has a positive effect on improving the display effect of the light-emitting transistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings are used to provide further understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0016] Figure 1 A first schematic diagram of a light emitting transistor provided in an embodiment of the present application;

[0017] Figure 2 A second schematic diagram of a light emitting transistor proposed in an embodiment of the present application;

[0018] Figure 3 A third schematic diagram of a light emitting transistor according to an embodiment of the present application;

[0019] Figure 4 A fourth schematic diagram of a light emitting transistor according to an embodiment of the present application;

[0020] Figure 5 A flowchart of the steps of the method for manufacturing a light-emitting transistor provided in an embodiment of the present application;

[0021] Figure 6 A fifth schematic diagram of a light emitting transistor provided in an embodiment of the present application;

[0022] Figure 7 A schematic diagram of a simulated IV characteristic curve of a light-emitting transistor provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0024] It should be noted that, although the functional modules are divided in the system schematic diagram and the logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the system or the order in the flowchart. The terms "first", "second", etc. in the specification, claims and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0025] The embodiments of the present application are further described below in conjunction with the accompanying drawings.

[0026] refer to Figure 1 , Figure 1 This is a first schematic diagram of a light emitting transistor provided in an embodiment of the present application. Figure 1 As shown, the light-emitting transistor proposed in the embodiment of the present application is a vertical structure, and the various layers in the light-emitting transistor are stacked in the vertical direction. The light-emitting transistor includes a gate, an insulating layer, an electron transport layer, a source metal, an active light-emitting layer, a hole transport layer and a drain metal. Figure 1 As shown, the upper surface of the gate is connected to the lower surface of the insulating layer; in the vertical direction, the upper surface of the active light-emitting layer is connected to the hole transport layer, and the lower surface of the active light-emitting layer is connected to the electron transport layer, and the electron transport layer is composed of a first sheet-like thin film semiconductor and a first grid-like semiconductor that are in close contact in the horizontal direction; the upper surface of the first grid-like semiconductor is connected to the lower surface of the active light-emitting layer; the upper surface of the first sheet-like thin film semiconductor is connected to the lower surface of the source metal; the upper surface of the hole transport layer is connected to the lower surface of the drain metal; the lower surface of the electron transport layer is connected to the upper surface of the insulating layer;

[0027] The upper surface of the insulating layer is connected to the lower surface of the electron transport layer; the electron transport layer is composed of a first sheet-like thin film semiconductor and a first grid-like semiconductor that are in close contact in the horizontal direction; the upper surface of the first sheet-like thin film semiconductor is connected to the source metal; the upper surface of the first grid-like semiconductor is connected to the lower surface of the active light-emitting layer; the upper surface of the active light-emitting layer is connected to the lower surface of the hole transport layer; and the upper surface of the hole transport layer is connected to the drain metal.

[0028] like Figure 1 In the light-emitting transistor shown, the gate is a single-gate structure, and the electron transport layer is regulated by the gate. When the gate regulates the electron transport layer to turn on, electrons are injected from the source metal into the light-emitting transistor, and the electrons accumulate in the electron transport layer near the insulating layer; while holes are injected from the drain metal, passing through the hole transport layer and the active light-emitting layer to reach the first grid-shaped semiconductor. Since in the embodiment of the present application, the active light-emitting layer and the first grid-shaped semiconductor are connected, the electrons and holes are radiatively recombined at the connection interface between the first grid-shaped semiconductor and the active light-emitting layer, emitting photons, so that the light-emitting transistor emits light. Since in the light-emitting transistor of the embodiment of the present application, the conductivity of the first grid-shaped semiconductor is lower than that of the first sheet-shaped thin film semiconductor, the current flowing through the electron transport layer will decrease under the regulation of the gate. When the electrons in the electron transport layer are exhausted and the electron concentration is very low, the off-state current between the source metal and the drain metal will also decrease. In addition, the first grid-shaped semiconductor further increases the gate's ability to regulate the active light-emitting layer and the electron transport layer, thereby further improving the switching ratio of the transistor.

[0029] In some embodiments, the first sheet-like thin film semiconductor and the first grid-like semiconductor have equal areas, and each occupies half of the area of ​​the electron transport layer. In the light-emitting transistor of the embodiment of the present application, the material for making the gate includes but is not limited to at least one of Cr / Au, Al, Mo, ITO, and Ti, the insulating layer is an oxidized insulating layer or a polymer insulating layer, the material of the electron transport layer includes at least one of TiO2, TPBi, ZnO, ZnMgO, SnO, and In2O3, and the material of the source metal and the drain metal includes at least one of Ag, Al, and Au; the material of the active light-emitting layer includes at least one of organic light-emitting materials, quantum dots, quantum wells, perovskites, and other light-emitting materials; the material of the hole transport layer includes at least one of PEDOT:PSS, CBP, PVK, TFB, CuI, and NiO.

[0030] In some embodiments, Figure 1As shown, the light-emitting transistor also includes a substrate. The material of the substrate includes but is not limited to Si, glass or a flexible substrate. In some embodiments, when the substrate is made of Si, the substrate can be directly used as a silicon gate, and used as a gate in the light-emitting transistor for current regulation, and other layers are also made on the basis of the silicon gate. In other embodiments, when the substrate is made of glass or a flexible substrate, the substrate is mainly used for supporting purposes. The light-emitting transistor uses the substrate as a base, and the gate is made on the substrate, and the other parts of the light-emitting transistor are sequentially made on the made gate.

[0031] In the above embodiment, combined with Figure 1 It is described that in a structure where the upper surface of the active light-emitting layer is connected to the hole transport layer, and the lower surface of the active light-emitting layer is connected to the electron transport layer, making half of the electron transport layer into a grid-like semiconductor can effectively reduce the off-state current and improve the switching ratio of the light-emitting transistor. In other words, in fact, the present application controls the carriers by changing the specific structure of the layer that transports the carriers, thereby achieving the effect of controlling the current. Because holes are also carriers, therefore, the embodiments of the present application propose that holes can also be controlled by changing the specific structure of the hole transport layer that transports holes, thereby achieving a similar effect of reducing the off-state current.

[0032] Reference Figure 2 , Figure 2 This is a second schematic diagram of the light emitting transistor proposed in the embodiment of the present application, as shown in FIG. Figure 2 As shown, in the vertical structure, the upper surface of the active light-emitting layer is connected to the lower surface of the electron transport layer, and the lower surface of the active light-emitting layer is connected to the hole transport layer: the hole transport layer is composed of a second sheet-like thin film semiconductor and a second grid-like semiconductor in close contact in the horizontal direction; the upper surface of the second grid-like semiconductor is connected to the lower surface of the active light-emitting layer; the upper surface of the second sheet-like thin film semiconductor is connected to the lower surface of the drain metal; the upper surface of the electron transport layer is connected to the lower surface of the source metal; the lower surface of the hole transport layer is connected to the upper surface of the insulating layer.

[0033] Figure 2 The light emitting transistor shown is Figure 1 In comparison, the main thing is to swap the positions of the electron transport layer and the hole transport layer, and adjust the positions of the drain metal and the source metal accordingly. However, in the actual application of light-emitting transistors, electrons still enter from the source, pass through the electron transport layer to the active light-emitting layer; holes still enter from the drain, pass through the hole transport layer to the active light-emitting layer, and then holes and electrons radiate and recombine in the active light-emitting layer to emit photons. Therefore, in fact Figure 1 and Figure 2 The light-emitting transistor shown in FIG. 1 has the same light-emitting principle, and the arrangement of the insulating layer, the gate and the substrate is not related to the arrangement of the above layers. Therefore, the following description is based on Figure 1 The structure of the light emitting transistor shown in FIG. 1 is used as an example to describe the structure of the light emitting transistor. Figure 1 , Figure 2 This is only another possible structure of the light-emitting transistor proposed based on the basic principle of reducing the off-state current of the light-emitting transistor proposed in this application. Figure 1 The embodiments of the light emitting transistor shown can be used in the same manner in Figure 2 The light emitting transistor shown in the figure can achieve similar technical effects, so the following will not be repeated. Figure 2 The light emitting transistor shown is described in detail.

[0034] Through the above content, the embodiments of this application are combined Figure 1 The specific composition and light-emitting principle of the light-emitting transistor when the gate is a single-gate structure are explained. Generally speaking, the manufacturing process of a transistor with a single gate is relatively simple and easy to produce, but since there is only one gate, the gate can only control one type of carrier (electron or hole). As a result, it is difficult to achieve balanced carrier injection in the light-emitting transistor, and the radiation recombination efficiency in the light-emitting transistor is also difficult to control, affecting the display effect.

[0035] Therefore, the embodiment of the present application also proposes that the gate in the light-emitting transistor can be a double-gate structure or an overlapping gate structure. Figure 3 , Figure 3 This is a third schematic diagram of a light emitting transistor proposed in an embodiment of the present application, as shown in FIG. Figure 3 As shown, the gate of the light-emitting transistor is a double-gate structure, and the gate is divided into a first gate and a second gate. The first gate and the second gate are electrically independent of each other, that is, the first gate and the second gate are not connected. Figure 2 As shown in FIG. 1 , a portion of the insulating layer is disposed between the first gate and the second gate to separate the first gate and the second gate. Similar to the single-gate structure, in a transistor with a double-gate structure, the lower surface of the first gate and the lower surface of the second gate are both connected to the substrate; the upper surface of the first gate and the upper surface of the second gate are both connected to the insulating layer. The connection relationship of the remaining part of the transistor is the same as the above Figure 1 The description is the same as that of , and will not be repeated here.

[0036] Since there are two gates, the two gates can independently control different carriers, such as Figure 3As shown, the first gate is arranged below the source electrode, and the first gate can independently regulate the electrons of the electron transport layer; similarly, the second gate is arranged below the hole transport layer, and the second gate can independently regulate the holes of the hole transport layer. By regulating the electrons and holes respectively through the two gates, the light-emitting transistor in the embodiment of the present application can well control the injection of charges and the magnitude of the current flowing through the active light-emitting layer. Since the holes and electrons radiate and recombine in the active light-emitting layer to emit photons, the two gates control the balanced injection of the two carriers into the active light-emitting layer, which can effectively improve the radiative recombination efficiency of electrons and holes, thereby improving the display effect of the light-emitting transistor.

[0037] Similarly, the overlapping gate structure with two gates can also effectively control electrons and holes respectively. Figure 4 , Figure 4 This is a fourth schematic diagram of a light emitting transistor proposed in an embodiment of the present application, as shown in FIG. Figure 4 As shown, the gate of the light-emitting transistor is an overlapping gate structure, and the gate includes a first gate and a second gate. Similar to the single-gate structure, the first gate is made directly on the substrate, and the lower surface of the first gate is connected to the substrate. On the upper surface of the first gate, an insulating layer is added, and the upper surface of the insulating layer is respectively connected to the insulating layer and the lower surface of the second gate. A second gate is made in a part of the upper surface of the insulating layer, and the lower surface of the second gate is connected to a part of the upper surface of the insulating layer. In this way, when viewed in the vertical direction, the area of ​​the first gate is larger than the area of ​​the second gate. After the second gate is made, an insulating layer is made in the remaining area of ​​the upper surface of the insulating layer except the second gate, and the insulating layer is connected to a part of the upper surface of the insulating layer. In the horizontal direction, the insulating layer and the second gate are in close contact, and the thickness of the insulating layer is greater than the thickness of the second gate. During the manufacturing process, the insulating layer is made to completely cover the upper surface of the second gate. The connection relationship of the remaining part of the transistor is the same as above. Figure 1 The description is the same as that of , and will not be repeated here.

[0038] In a transistor with an overlapping gate structure, similarly, the first gate and the second gate can also control different carriers respectively to achieve balanced injection of carriers in the active light-emitting layer, thereby effectively improving the radiation recombination efficiency of electrons and holes and improving the display effect of the light-emitting transistor.

[0039] The following describes a method for manufacturing a light-emitting transistor according to an embodiment of the present application in combination with the structure of the light-emitting transistor described above.

[0040] Reference Figure 5 , Figure 5 A flowchart of a method for manufacturing a light-emitting transistor provided in an embodiment of the present application, the method includes but is not limited to steps S500-S570:

[0041] S500, cleaning and drying the substrate made of glass or flexible substrate;

[0042] Specifically, it is mentioned in the above content that when the substrate is made of glass or a flexible substrate, the substrate mainly plays a supporting role. After the prepared substrate is cleaned and dried, a light-emitting transistor can be manufactured on the substrate.

[0043] S510, depositing a gate on the upper surface of the substrate;

[0044] Specifically, when a single-gate structure gate is required, a gate layer is deposited on the cleaned substrate surface. When a dual-gate structure gate is required, a gate layer is first deposited on the substrate surface. After the gate is completed, the single-layer gate is patterned to separate the single-pass gate to obtain the following: Figure 3 The first gate and the second gate are electrically independent of each other. When it is necessary to make a gate with an overlapping gate structure, a single-layer first gate is first deposited on a substrate, and then an insulating layer is deposited on the upper surface of the first gate. After the insulating layer is made, the upper surface of the insulating layer is divided into a first area and a second area, and the second gate is deposited in the first area. When viewed in the vertical direction, the area of ​​the second gate is smaller than that of the first gate.

[0045] In some embodiments, when the substrate is made of Si, the substrate can be directly used as a silicon gate. The Si substrate can be cleaned and dried before use, without the need to manufacture a gate on the surface of the silicon gate.

[0046] S520, spin coating or depositing an insulating layer on the upper surface of the gate;

[0047] Specifically, when the gate is a single-gate structure, refer to Figure 1 , directly spin-coat or deposit an insulating layer on the upper surface of the single-layer gate. When the gate is a double-gate structure, refer to Figure 3 , an insulating layer is deposited on the upper surfaces of the first gate and the second gate, and a portion of the insulating layer can be deposited in the gap between the first gate and the second gate. When the gate is an overlapping gate structure, refer to Figure 4 Since the area of ​​the second gate is smaller than that of the first gate, when the second gate is completed, it is equivalent to having an extra "half-layer" of gate on the isolation layer. Then, an insulating layer is spin-coated or deposited on the second area of ​​the upper surface of the isolation layer (that is, the area except the second gate) and the upper surface of the second gate, so that the insulating layer covers both the second area of ​​the upper surface of the isolation layer and completely covers the upper surface of the second gate.

[0048] S530, depositing an electron transport layer on the upper surface of the insulating layer, wherein the electron transport layer is a first sheet-shaped thin film semiconductor;

[0049] Specifically, no matter which of the above-mentioned gate structures is used, the upper surface of the gate is covered by an insulating layer, and an electron transport layer is deposited on the upper surface of the insulating layer. At this time, the electron transport layer is in the form of a first sheet-like thin film semiconductor.

[0050] S540, performing patterning on half of the first sheet-like thin film semiconductor in the horizontal direction to obtain a first grid-like semiconductor;

[0051] Specifically, refer to Figure 6 , Figure 6 The fifth schematic diagram of the light-emitting transistor provided in the embodiment of the present application. In the horizontal direction, the first sheet-like thin film semiconductor is divided into two, and half of the first sheet-like thin film semiconductor is patterned to obtain a grid-shaped semiconductor. Figure 6 As shown, half of the electron transport layer is a first sheet-like thin film semiconductor, and the other half is a first grid-like semiconductor.

[0052] S550 , spin coating or depositing an active light emitting layer on the upper surface of the first grid-shaped semiconductor.

[0053] S560, depositing a hole transport layer on the upper surface of the active light-emitting layer.

[0054] S570, in a vacuum environment, evaporating or sputtering a source metal on the upper surface of the first sheet-like thin film semiconductor, and evaporating or sputtering a drain metal on the upper surface of the hole transport layer;

[0055] Specifically, in a vacuum environment, a source metal is evaporated or sputtered on the upper surface of the first sheet-like thin film semiconductor, and one end of the source metal is used to introduce electrons; a drain metal is evaporated or sputtered on the upper surface of the hole transport layer, and one end of the drain metal is used to introduce holes. The electrons and holes will pass through the electron transport layer and the hole transport layer to reach the active light-emitting layer, and undergo radiative recombination in the active light-emitting layer to emit photons.

[0056] Through steps S500-S570, the embodiment of the present application proposes a method for manufacturing a light-emitting transistor. According to the light-emitting transistor manufactured by the manufacturing method, the grid-shaped semiconductor portion can effectively reduce the current size of the light-emitting transistor, so that the off-state current is reduced; and the grid-shaped semiconductor increases the gate's ability to regulate the active light-emitting layer, further improving the transistor's switching ratio, thereby effectively reducing the power loss of the light-emitting transistor, which has a positive effect on improving the display effect of the light-emitting transistor.

[0057] The following describes the manufacturing process of the light-emitting transistor in the embodiment of the present application in combination with actual manufacturing parameters. First, a substrate made of glass or a flexible substrate is ultrasonically cleaned in at least one solution of acetone, ethanol and water, and then the substrate is blown dry with nitrogen. When the gate is a single-gate structure, a gate layer with a thickness of 30-50nm is deposited on the substrate; when the gate is a double-gate structure, a gate layer with a thickness of 30-50nm is deposited on the substrate, and the gate is patterned to form a double-gate structure; when the gate is an overlapping gate structure, a first gate layer of 50-70nm is first deposited on the substrate, and then an insulating layer with a thickness of 100nm is grown by ALD, and a second gate layer with a thickness of 30-50nm is deposited on a partial area of ​​the upper surface of the insulating layer. A 100-300nm insulating layer is spin-coated or PECVD-coated on the upper surface of the gate (if it is an overlapping gate, it is on a partial area of ​​the insulating layer and the upper surface of the second gate). An electron transport layer with a thickness of about 40nm is spin-coated or deposited on the insulating layer. In the horizontal direction, 1 / 2 of the electron transport layer is made into a grid structure by nanoimprinting or photolithography. The electron transport layer is composed of a first sheet-like thin film semiconductor and a first grid-like semiconductor that are in close contact in the horizontal direction. Cover the upper surface of the first sheet-like thin film semiconductor, spin-coat or evaporate an active light-emitting layer with a thickness of about 50nm on the first grid-like semiconductor, and deposit a hole transport layer with a thickness of about 35nm on the active light-emitting layer. Finally, remove the cover on the upper surface of the first sheet-like thin film semiconductor, evaporate or sputter 70-120nm of metal in a vacuum environment with a vacuum degree greater than 3.8×10-3, make a source metal on the first sheet-like thin film semiconductor, and make a drain metal on the hole transport layer, and complete the production of the light-emitting transistor of the embodiment of the present application.

[0058] The light-emitting transistor obtained by the above manufacturing steps is simulated by TCAD to obtain a simulated IV characteristic curve. Figure 7 , Figure 7 Schematic diagram of the simulated IV characteristic curve of the light emitting transistor provided in the embodiment of the present application. Figure 7 As shown, the first curve 710 represents the IV characteristic curve of the single-gate light-emitting transistor without a grid, the second curve 720 represents the IV characteristic curve of the single-gate light-emitting transistor with a grid, and the third curve 730 represents the IV characteristic curve of the double-gate light-emitting transistor with a grid. Figure 7 The horizontal axis represents the gate voltage, and the vertical axis represents the drain current. Figure 7 At the position where the horizontal coordinate is 0, it can be seen that the leakage current of the grid single-gate light-emitting transistor and the grid double-gate light-emitting transistor is about 10 -10 A, while the leakage current of a gridless single-gate light-emitting transistor is about 10 -8A. It can be seen that the leakage current of the grid single-gate light-emitting transistor and the grid double-gate light-emitting transistor is about two orders of magnitude smaller than the leakage current of the non-grid single-gate light-emitting transistor. Therefore, the light-emitting transistor proposed in the embodiment of the present application has a lower off-state current, and the switching ratio of the transistor is significantly improved. Figure 7 It can also be found that the grid dual-gate light-emitting transistor can obtain a relatively high on-state current with a very small leakage current, further improving the switching ratio of the transistor, thereby effectively improving the display performance of the light-emitting transistor.

[0059] It should be noted that the manufacturing processes of the functional layers and metal layers described in all the steps of manufacturing the light-emitting transistors include but are not limited to spin coating, scraping, nanoimprinting, printing, evaporation, physical deposition or chemical deposition, and the patterning process includes but is not limited to photolithography, nanoimprinting, evaporation, and printing methods, which are not listed here one by one. The above manufacturing process is not a limitation on the implementation of the present invention. For ordinary technicians in the relevant field, they can choose a suitable manufacturing process to manufacture the light-emitting transistor of the embodiment of the present application.

[0060] The above is a specific description of the preferred implementation of the present application, but the present application is not limited to the above-mentioned implementation mode. Technical personnel familiar with the field can also make various equivalent deformations or substitutions without violating the spirit of the present application. These equivalent deformations or substitutions are all included in the scope defined by the claims of the present application.

Claims

1. A light emitting transistor, the light emitting transistor being a vertical structure, characterized in that: The light-emitting transistor includes a gate, an insulating layer, an electron transport layer, a source metal, an active light-emitting layer, a hole transport layer and a drain metal; The upper surface of the gate is connected to the lower surface of the insulating layer; In the vertical direction, when the upper surface of the active light-emitting layer is connected to the hole transport layer, and the lower surface of the active light-emitting layer is connected to the electron transport layer: The electron transport layer is composed of a first sheet-like thin film semiconductor and a first grid-like semiconductor that are in close contact in a horizontal direction; The upper surface of the first grid-shaped semiconductor is connected to the lower surface of the active light-emitting layer; The upper surface of the first sheet-shaped thin film semiconductor is connected to the lower surface of the source metal; The upper surface of the hole transport layer is connected to the lower surface of the drain metal; The lower surface of the electron transport layer is connected to the upper surface of the insulating layer; or, In the vertical direction, when the upper surface of the active light-emitting layer is connected to the lower surface of the electron transport layer, and the lower surface of the active light-emitting layer is connected to the hole transport layer: The hole transport layer is composed of a second sheet-like thin film semiconductor and a second grid-like semiconductor that are in close contact with each other in a horizontal direction; The upper surface of the second grid-shaped semiconductor is connected to the lower surface of the active light-emitting layer; The upper surface of the second sheet-like thin film semiconductor is connected to the lower surface of the drain metal; The upper surface of the electron transport layer is connected to the lower surface of the source metal; The lower surface of the hole transport layer is connected to the upper surface of the insulating layer.

2. The light emitting transistor according to claim 1, characterized in that: The light emitting transistor further includes: a substrate; The substrate material includes one of Si, glass or flexible substrate; The substrate is connected to the gate.

3. The light emitting transistor according to claim 2, characterized in that: The gate includes a first gate and a second gate that are electrically independent of each other; A lower surface of the first gate and a lower surface of the second gate are both connected to the substrate; An upper surface of the first gate and an upper surface of the second gate are both connected to the insulating layer.

4. The light emitting transistor according to claim 2, characterized in that: The light emitting transistor further includes an insulating layer, and the gate includes a first gate and a second gate; The lower surface of the first gate is connected to the substrate; The upper surface of the first gate is connected to the lower surface of the isolation layer; The upper surface of the isolation layer is connected to the lower surfaces of the insulating layer and the second gate respectively; The insulating layer and the second gate are in close contact with each other in a horizontal direction; The upper surface of the second gate is covered by the insulating layer; In a vertical direction, an area of ​​the first gate is larger than an area of ​​the second gate.

5. The light emitting transistor according to any one of claims 1 or 2, characterized in that: In the vertical direction, the areas of the sheet-like thin film semiconductor and the grid-like semiconductor are equal, and the area of ​​the sheet-like thin film semiconductor is half of the area of ​​the electron transport layer.

6. The light emitting transistor according to any one of claims 1 or 2, characterized in that: The material of the gate includes at least one of Cr / Au, Al, Mo, ITO, and Ti; The insulating layer is an oxidized insulating layer or a polymer insulating layer; The material of the electron transport layer includes at least one of TiO2, TPBi, ZnO, ZnMgO, SnO, and In2O3; The material of the source metal and the drain metal includes at least one of Ag, Al, and Au; The material of the active light-emitting layer includes at least one of an organic light-emitting material, a quantum dot, a quantum well, and a perovskite; The material of the hole transport layer includes at least one of PEDOT:PSS, CBP, PVK, TFB, CuI, and NiO.

7. A method for manufacturing a light emitting transistor, wherein the light emitting transistor is a vertical structure, characterized in that: The method comprises: Clean and dry the substrate made of glass or flexible substrate; Depositing a gate on the upper surface of the substrate; Spin coating or depositing an insulating layer on the upper surface of the gate; An electron transport layer is deposited on the upper surface of the insulating layer, and the electron transport layer is a sheet-like thin film semiconductor In the horizontal direction, patterning is performed on half of the sheet-like thin film semiconductor to obtain a grid-like semiconductor; Spin coating or depositing an active light emitting layer on the upper surface of the grid-shaped semiconductor; Depositing a hole transport layer on the upper surface of the active light-emitting layer; In a vacuum environment, a source metal is evaporated or sputtered on the upper surface of the sheet-like thin film semiconductor, and a drain metal is evaporated or sputtered on the upper surface of the hole transport layer.

8. The method for manufacturing a light emitting transistor according to claim 7, characterized in that: After the step of depositing a gate layer on the upper surface of the substrate, the method further comprises: The gate is patterned to obtain a first gate and a second gate that are electrically independent of each other.

9. The method for manufacturing a light emitting transistor according to claim 7, characterized in that: The step of depositing a gate on the upper surface of the substrate comprises: Depositing a first gate on the upper surface of the substrate; depositing an isolation layer on the upper surface of the first gate; The upper surface of the insulating layer consists of a first region and a second region; depositing a second gate on the first region; Wherein, the area of ​​the first gate is greater than the area of ​​the second gate; The insulating layer is spin-coated or deposited on the upper surface of the gate, specifically: An insulating layer is deposited on the second region and upper surfaces of the second gate.

10. The method for manufacturing a light emitting transistor according to claim 7, characterized in that: The step of cleaning and drying a substrate made of glass or a flexible substrate and depositing a gate on the upper surface of the substrate comprises: The Si substrate is cleaned and dried, and the Si substrate is used as a gate.

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