A gate-regulated injectionless light-emitting device structure

Abstract

The application discloses a grid regulation non-injection type light-emitting device structure, and relates to the field of photoelectric display.The device structure comprises a non-injection type light-emitting unit, a grid insulation layer and a grid regulation electrode.The non-injection type light-emitting unit comprises a first electrode, an insulation layer, a quantum dot light-emitting layer, a carrier transmission / injection layer and a second electrode in sequence.The grid insulation layer is arranged between the non-injection type light-emitting unit and the grid regulation electrode, and the grid regulation electrode is located on the side of the first electrode or the second electrode.In the working process of the device, the first electrode and the second electrode are applied with a first alternating current power supply, the first alternating current power supply is used for providing an electric field for the non-injection type light-emitting unit to make the non-injection type light-emitting unit emit light, and a bias power supply is applied to the grid regulation electrode relative to the first electrode or the second electrode, the bias power supply is used for constructing an electric field to regulate the mobility of carriers in the non-injection type light-emitting unit, and the light-emitting brightness or the light-emitting efficiency of the non-injection type light-emitting unit is adjusted.The application realizes the improvement of the light-emitting efficiency or the improvement of the light-emitting brightness through the grid regulation.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic displays, and in particular to a gate-controlled injection-free light-emitting device structure. Background Technology

[0002] Quantum dots, as luminescent materials, possess advantages such as narrow half-width at half-maximum (WHM), high color purity, extremely high quantum yield, and full-spectrum tunability. Therefore, quantum dot light-emitting diodes (QLEDs) have a high probability of becoming the dominant force in the field of novel display devices. Injection-free quantum dot light-emitting diodes (QLEDs) have unique advantages in the micro-display industry and in overcoming bonding technology barriers, making them highly promising for high-end display applications.

[0003] However, the luminous efficiency or brightness of QLED devices, especially those without injection, is greatly affected by the carrier recombination process. This places high demands on the quality of the electric field generating device and the quantum dot emitting layer used with them, and this experimental process requires a significant investment of time, materials, and manpower. Furthermore, similar issues exist in OLED devices. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a gate-controlled injection-free light-emitting device structure, which aims to improve the luminous efficiency or the luminous brightness through gate control.

[0005] To achieve the above objectives, the present invention provides a gate-controlled injection-free light-emitting device structure, the device structure comprising: an injection-free light-emitting unit, a gate insulating layer, and a gate control electrode; the gate insulating layer is disposed between the injection-free light-emitting unit and the gate control electrode;

[0006] The injection-free light-emitting unit includes: a light-emitting material layer, a first electrode disposed on both sides of the light-emitting material layer, a second electrode, a first dielectric layer disposed between the first electrode and the light-emitting material layer, and a second dielectric layer disposed between the second electrode and the light-emitting material layer;

[0007] At least one of the first dielectric layer and the second dielectric layer is an uninjected insulating layer, and the remainder is a carrier transport / injection layer;

[0008] The gate control electrode is located on the side where the first electrode or the second electrode is located;

[0009] In operation of the device, the first electrode and the second electrode apply a first alternating current power source for powering the injection-free light emitting unit to emit light, and the gate control electrode applies a bias power source relative to the first electrode and / or the second electrode for building an electric field to control the mobility of the carriers in the injection-free light emitting unit to adjust the light emitting brightness or the light emitting efficiency of the injection-free light emitting unit.

[0010] In an embodiment, the injection-free light emitting unit comprises, in sequence, a first electrode, an injection-free insulating layer, a light emitting material layer, an injection-free insulating layer, and a second electrode; the light emitting material layer is a PN light emitting layer, a quantum dot light emitting layer, or an organic light emitting layer; the light emitting material layer is a P-type region adjacent to the first electrode and an N-type region adjacent to the second electrode.

[0011] When the majority carriers of the light emitting material layer are electron type carriers and the gate control electrode is located at the first electrode side; wherein the gate control electrode applies a positive potential relative to the first electrode to increase the recombination amount of the hole type carriers in the light emitting material layer, so as to improve the light emitting brightness and the light emitting efficiency of the injection-free light emitting unit;

[0012] When the majority carriers of the light emitting material layer are hole type carriers and the gate control electrode is located at the first electrode side; wherein the gate control electrode applies a negative potential relative to the first electrode to reduce the recombination amount of the hole type carriers in the light emitting material layer, so as to improve the light emitting efficiency of the injection-free light emitting unit; the gate control electrode applies a positive potential relative to the first electrode to increase the hole type carriers in the light emitting material layer, so as to improve the light emitting brightness of the injection-free light emitting unit;

[0013] When the majority carriers of the light emitting material layer are hole type carriers and the gate control electrode is located at the second electrode side; the gate control electrode applies a negative positive potential relative to the second electrode to increase the recombination amount of the electron type carriers in the light emitting material layer, so as to improve the light emitting efficiency and the light emitting brightness of the injection-free light emitting unit;

[0014] When the majority carriers of the light emitting material layer are electron type carriers and the gate control electrode is located at the second electrode side; wherein the gate control electrode applies a negative potential relative to the second electrode to increase the recombination amount of the electron type carriers in the light emitting material layer, so as to improve the light emitting brightness of the injection-free light emitting unit; the gate control electrode applies a positive potential relative to the second electrode to reduce the recombination amount of the electron type carriers in the light emitting material layer, so as to improve the light emitting efficiency of the injection-free light emitting unit.

[0015] In an embodiment, the non-injection light emitting unit is configured to include, in sequence, a first electrode, a non-injection insulating layer, a light emitting material layer, an electron transport / injection layer, and a second electrode; or include, in sequence, a first electrode, a hole transport / injection layer, a light emitting material layer, a non-injection insulating layer, and a second electrode; the light emitting material layer is a PN light emitting layer, a quantum dot light emitting layer, or an organic light emitting layer; when the light emitting material layer is a PN light emitting layer, the light emitting material layer is a P-type region adjacent to the first electrode and an N-type region adjacent to the second electrode.

[0016] In an embodiment, when the majority carriers of the light emitting material layer are electron type carriers and the gate control electrode is located on the first electrode side; wherein the gate control electrode applies a positive potential relative to the first electrode to increase the hole type carriers in the light emitting material layer, so as to improve the light emitting efficiency and the light emitting brightness of the non-injection light emitting unit;

[0017] In an embodiment, when the majority carriers of the light emitting material layer are hole type carriers and the gate control electrode is located on the first electrode side; wherein the gate control electrode applies a negative potential relative to the first electrode to reduce the hole type carriers in the light emitting material layer, so as to improve the light emitting efficiency of the non-injection light emitting unit; the gate control electrode applies a positive potential relative to the first electrode to increase the hole type carriers in the light emitting material layer, so as to improve the light emitting brightness of the non-injection light emitting unit;

[0018] In an embodiment, when the majority carriers of the light emitting material layer are hole type carriers and the gate control electrode is located on the second electrode side; the gate control electrode applies a negative positive potential relative to the second electrode to increase the recombination amount of the electron type carriers in the light emitting material layer, so as to improve the light emitting efficiency and the light emitting brightness of the non-injection light emitting unit;

[0019] In an embodiment, when the majority carriers of the light emitting material layer are electron type carriers and the gate control electrode is located on the second electrode side; wherein the gate control electrode applies a negative potential relative to the second electrode to increase the recombination amount of the electron type carriers in the light emitting material layer, so as to improve the light emitting brightness of the non-injection light emitting unit; the gate control electrode applies a positive potential relative to the second electrode to reduce the recombination amount of the electron type carriers in the light emitting material layer, so as to improve the light emitting efficiency of the non-injection light emitting unit.

[0020] In an embodiment, the bias power supply is an adjustable voltage power supply, which is adjusted according to the light emitting brightness or the light emitting efficiency requirement.

[0021] In one embodiment, a current-limiting resistor is further connected in series between the gate control electrode and the bias power supply circuit.

[0022] In one embodiment, the gate control electrode is arranged on a back side of the device structure opposite to a light-emitting side.

[0023] Advantages of the present application: The present application builds an internal electric field in the injection-free light-emitting device by the gate control, realizes the control of the carrier mobility, and further realizes the control of the light-emitting efficiency or the light-emitting brightness, which is helpful to improve the light-emitting efficiency or the light-emitting brightness. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a schematic diagram of a gate-controlled injection-free light-emitting device structure in one embodiment of the present application;

[0025] Figure 2 is a schematic diagram of a double-end injection-free gate-controlled injection-free light-emitting device structure in one embodiment of the present application;

[0026] Figure 3 is a control schematic diagram of four double-end injection-free gate-controlled injection-free light-emitting device structures in one embodiment of the present application;

[0027] Figure 4 is a schematic diagram of a hole injection-free gate-controlled injection-free light-emitting device structure in one embodiment of the present application;

[0028] Figure 5 is a control schematic diagram of four hole injection-free gate-controlled injection-free light-emitting device structures in one embodiment of the present application;

[0029] Figure 6 is a schematic diagram of an electron injection-free gate-controlled injection-free light-emitting device structure in one embodiment of the present application;

[0030] Figure 7 is a control schematic diagram of four electron injection-free gate-controlled injection-free light-emitting device structures in one embodiment of the present application. DETAILED DESCRIPTION

[0031] The embodiments of the present patent are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present patent, and cannot be understood as a limitation of the present patent.

[0032] In the description of the present patent, it needs to be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present patent and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present patent.

[0033] In the description of the present patent, it needs to be understood that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "setting" should be understood broadly, for example, it can be fixedly connected, set, or it can be detachably connected, set, or integrally connected, set. For those skilled in the art, the specific meaning of the above terms in the present patent can be understood according to the specific circumstances.

[0034] The embodiment of the present application provides a gate-regulated non-injection type light-emitting device structure, as shown in the figure. Figures 1-7 In the present application, by arranging a gate-regulated electrode on the side of the majority carrier transport / injection layer and constructing a built-in electric field under the condition of applying an electric potential, the generation of majority carriers is reduced, and the excessive recombination of majority carriers is avoided to cause the decrease of light-emitting efficiency; at the same time, on the other hand, the gate-regulated electrode can also be applied with an opposite electric potential to construct a built-in electric field to increase the generation of majority carriers and improve the brightness of the device.

[0035] In addition, when the gate-regulated electrode is arranged on the side of the minority carrier transport / injection layer, the recombination rate can also be improved by increasing the minority carriers, and the brightness and light-emitting efficiency of the device are improved.

[0036] For example, when the majority carriers of the device are electrons, the gate-regulated electrode is arranged on the side of the electron transport layer, a built-in electric field is formed when a positive gate voltage is applied, the generation of electrons from the electron transport layer is reduced, and the influence of the holes in the hole transport layer is small, so that the excessive electrons are not recombined to cause the decrease of light-emitting efficiency. On the contrary, the built-in electric field formed by applying a negative gate voltage enhances the number of electron carriers, improves the recombination speed, and improves the brightness.

[0037] Embodiment 1

[0038] As shown in the figure, Figures 1-7 In an embodiment of the present application, a gate-regulated non-injection type light-emitting device structure is provided, which comprises: a non-injection type light-emitting unit, a gate insulating layer, and a gate-regulated electrode; the gate insulating layer is arranged between the non-injection type light-emitting unit and the gate-regulated electrode;

[0039] The injection-free light-emitting unit includes: a light-emitting material layer, a first electrode disposed on both sides of the light-emitting material layer, a second electrode, a first dielectric layer disposed between the first electrode and the light-emitting material layer, and a second dielectric layer disposed between the second electrode and the light-emitting material layer;

[0040] At least one of the first dielectric layer and the second dielectric layer is an uninjected insulating layer, and the remainder is a carrier transport / injection layer;

[0041] The gate control electrode is located on the side where the first electrode or the second electrode is located;

[0042] When the device is in operation, a first AC power supply is applied to the first electrode and the second electrode. The first AC power supply is used to power the injection-free light-emitting unit to emit light. The gate control electrode applies a bias power supply relative to the first electrode and / or the second electrode. The bias power supply is used to construct an electric field to control the mobility of charge carriers in the injection-free light-emitting unit and adjust the luminous brightness or luminous efficiency of the injection-free light-emitting unit.

[0043] This invention patent primarily protects the structure, but structures implemented using other processes based on the structure of this invention also fall within the scope of protection of this invention.

[0044] Example 2

[0045] like Figure 2 As shown, based on the first embodiment of the present invention, the injection-free light-emitting device provided in the second embodiment of the present invention is a double-ended injection-free type; in this case, the injection-free light-emitting unit sequentially includes: a first electrode, an injection-free insulating layer, a light-emitting material layer, an injection-free insulating layer, and a second electrode; the light-emitting material layer is a PN light-emitting layer, a quantum dot light-emitting layer, or an organic light-emitting layer; the light-emitting material layer is a P-type region near the first electrode and an N-type region near the second electrode.

[0046] like Figure 3 As shown, the device structure achieves the control of luminous brightness and luminous efficiency in the following ways.

[0047] (a) When the majority carriers of the light-emitting material layer are electron carriers and the gate control electrode is located on the side of the first electrode; wherein, the gate control electrode applies a positive potential relative to the first electrode to increase the recombination amount of the hole carriers in the light-emitting material layer, so as to improve the luminous brightness and luminous efficiency of the injection-free light-emitting unit;

[0048] (b) when the majority carriers of the light-emitting material layer are hole-type carriers and the gate control electrode is located at the first electrode side; wherein the gate control electrode applies a negative potential to the first electrode to reduce the recombination amount of the hole-type carriers in the light-emitting material layer, so as to improve the light-emitting efficiency of the non-injection light-emitting unit; the gate control electrode applies a positive potential to the first electrode to increase the hole-type carriers in the light-emitting material layer, so as to improve the light-emitting brightness of the non-injection light-emitting unit;

[0049] (c) when the majority carriers of the light-emitting material layer are hole-type carriers and the gate control electrode is located at the second electrode side; the gate control electrode applies a negative positive potential to the second electrode to increase the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the light-emitting efficiency and the light-emitting brightness of the non-injection light-emitting unit;

[0050] (d) when the majority carriers of the light-emitting material layer are electron-type carriers and the gate control electrode is located at the second electrode side; wherein the gate control electrode applies a negative potential to the second electrode to increase the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the light-emitting brightness of the non-injection light-emitting unit; the gate control electrode applies a positive potential to the second electrode to reduce the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the light-emitting efficiency of the non-injection light-emitting unit.

[0051] Embodiment 3

[0052] As Figures 4-5 shown, on the basis of the first embodiment of the present application, the non-injection light-emitting device provided by the third embodiment of the present application is single-end non-injection, and specifically adopts hole non-injection.

[0053] The non-injection light-emitting unit is configured to sequentially include a first electrode, a non-injection insulating layer, a light-emitting material layer, an electron transport / injection layer, and a second electrode; the light-emitting material layer is a PN light-emitting layer, a quantum dot light-emitting layer, or an organic light-emitting layer; when the light-emitting material layer is a PN light-emitting layer, the light-emitting material layer is a P-type region adjacent to the first electrode and an N-type region adjacent to the second electrode.

[0054] As Figure 5 shown, the device structure realizes the regulation of the light-emitting brightness and the light-emitting efficiency in the following manner.

[0055] (a) when the majority carriers of the light-emitting material layer are electron type carriers and the gate control electrode is located at the first electrode side; wherein the gate control electrode applies a positive potential to the first electrode to increase the hole type carriers in the light-emitting material layer, so that the light-emitting efficiency and luminance of the non-injection light-emitting unit are improved;

[0056] (b) when the majority carriers of the light-emitting material layer are hole type carriers and the gate control electrode is located at the first electrode side; wherein the gate control electrode applies a negative potential to the first electrode to reduce the hole type carriers in the light-emitting material layer, so that the light-emitting efficiency of the non-injection light-emitting unit is improved; the gate control electrode applies a positive potential to the first electrode to increase the hole type carriers in the light-emitting material layer, so that the luminance of the non-injection light-emitting unit is improved;

[0057] (c) when the majority carriers of the light-emitting material layer are hole type carriers and the gate control electrode is located at the second electrode side; the gate control electrode applies a negative positive potential to the second electrode to increase the recombination amount of the electron type carriers in the light-emitting material layer, so that the light-emitting efficiency and luminance of the non-injection light-emitting unit are improved;

[0058] (d) when the majority carriers of the light-emitting material layer are electron type carriers and the gate control electrode is located at the second electrode side; wherein the gate control electrode applies a negative potential to the second electrode to increase the recombination amount of the electron type carriers in the light-emitting material layer, so that the luminance of the non-injection light-emitting unit is improved; the gate control electrode applies a positive potential to the second electrode to reduce the recombination amount of the electron type carriers in the light-emitting material layer, so that the light-emitting efficiency of the non-injection light-emitting unit is improved.

[0059] The technical solutions of the embodiments are further described below with the preparation of a QLED device.

[0060] In the embodiments, the first electrode can be selected as the side close to the glass substrate, or the gate control electrode can be selected as the side close to the glass substrate. The following describes the device preparation process with the first electrode side as the first layer of the glass substrate, and it is worth mentioning that the preparation process is only a supplementary description and cannot limit the protection scope of the invention patent. The same or similar device structures as the present application should be within the protection scope of the invention patent.

[0061] Illustratively, the following second embodiment describes the preparation process of a quantum dot light-emitting diode device with hole non-injection and electron majority carriers, wherein the gate control electrode is arranged at the second electrode side.

[0062] Step S11, injection-free light-emitting unit

[0063] Step S111, preparing ITO conductive glass, in which the ITO film layer serves as the layer of the first electrode. The size of the customized glass substrate is 3 cm x 3 cm x 0.11 cm, the ITO electrode width is 0.6 cm, and the electrode and the rear electrode constitute four light-emitting areas with a light-emitting area of 2 mm x 2 mm. The work function of the ITO electrode is -4.7 eV to -5.1 eV, and the resistivity is 15 Ω·m.

[0064] Step S112, cleaning and activating the glass electrode. The conductive glass customized in step S111 is cleaned, and the specific steps are sequentially ultrasonic cleaning in a surfactant, deionized water, acetone, and isopropanol for 30 minutes each, for a total of 2 hours. The conductive glass that has been thoroughly cleaned is dried with a nitrogen gun. The cleaned and dried conductive glass is surface activated to better infiltrate and coat the functional layer material. The activation methods include ultraviolet activation, ozone activation, or heating, and the preferred activation method in this embodiment is to place the glass in an ultraviolet oven for 10 minutes.

[0065] Step S113, preparing an insulating layer. The material of the insulating layer includes but is not limited to aluminum oxide, lithium fluoride, or P(VDF-TrFE), etc., and the preferred insulating layer in this embodiment is an aluminum oxide film.

[0066] In this embodiment, aluminum oxide is used as the insulating layer. The glass electrode prepared in step S11 is placed in an atomic layer deposition system, and aluminum oxide is deposited on the surface of the second electrode prepared in step S117 as an insulating layer by atomic layer deposition technology. The thickness of the aluminum oxide layer is about 50 nm.

[0067] Step S114, preparing an electron-rich quantum dot layer. The quantum dot is a uniform film layer with a thickness of about 30 nm, and the coating method selected in this embodiment is spin coating followed by annealing, with an annealing temperature of 75°C and an annealing time of 10 minutes. The coating raw material is a n-octane dispersion solution with a concentration of 20 mg / ml.

[0068] Step S115, preparing an electron transport layer of magnesium zinc oxide (Zn1-xMgxO). The Zn1-xMgxO layer is a uniform film layer with a thickness of about 90 nm, and the coating method selected in this embodiment is spin coating followed by annealing, with an annealing temperature of 75°C and an annealing time of 10 minutes. The coating raw material is an ethanol solution with a concentration of 25 mg / ml.

[0069] Step S116, preparing a second electrode. The conductive glass treated in steps S112 to S116 is placed in a vacuum evaporation instrument, and a silver electrode is evaporated onto the surface of the electron transport layer using a customized mask. The thickness of the electrode is about 100 nm.

[0070] Step S12, preparing an insulating layer

[0071] The material of the insulation layer includes, but is not limited to, aluminum oxide, lithium fluoride, or P(VDF-TrFE), etc. In the present embodiment, aluminum oxide film is preferred as the insulation layer.

[0072] In the present embodiment, aluminum oxide is used as the insulation layer. The glass electrode prepared in step S11 is placed in an atomic layer deposition system, and aluminum oxide is deposited on the surface of the second electrode prepared in step S117 by using atomic layer deposition technology. The thickness of the aluminum oxide layer is about 50 nanometers.

[0073] In addition, in the embodiment in which lithium fluoride is used as the insulation layer, the following scheme can be used: the glass electrode prepared in step S11 is placed in a vacuum evaporation instrument, and lithium fluoride powder is evaporated on the surface of the second electrode by using vacuum evaporation technology. The thickness of the lithium fluoride layer is about 120 nanometers.

[0074] In addition, in the embodiment in which P(VDF-TrFE) is used as the insulation layer, the following scheme can be used: P(VDF-TrFE) powder is dissolved in DMF at a concentration of 100 mg / ml, and spin coating is used on the surface of the second electrode. The spin coating speed is 1000 rpm / min, the time is 30 seconds, the annealing temperature is selected to be 90 degrees Celsius, and the annealing time is 1-3 hours.

[0075] Step S13, preparing a control gate control electrode

[0076] Silver electrodes are evaporated on the surface of the insulation layer by using a custom mask. The thickness of the electrode is about 100 nanometers.

[0077] Step S14, building a test circuit

[0078] The starting voltage of the double-end QLED is obtained by the test circuit, and the insulation property of the insulation layer is verified to ensure the accuracy of the third electrode control.

[0079] Step S141, obtaining the starting voltage (Vturn-on) of the double-end QLED. The first electrode and the second electrode of the QLED device prepared by S11 to S13 are connected by a loop, ensuring that the device emits light through an alternating current loop under the premise of not emitting light under direct current. The light-emitting efficiency of the double-end QLED without control is determined by a semiconductor device test system.

[0080] Step S142, verifying the insulation property of the insulation layer. The second electrode and the gate control electrode of the QLED device prepared by S11 to S13 are connected by a direct current loop, and the performance of the insulation layer is determined by a semiconductor test system.

[0081] Step S15, building a control circuit

[0082] The three-terminal QLED device, prepared through S11 to S13 and tested and verified through S14, is placed into the control circuit.

[0083] The primary charge carrier type of the aforementioned device is electrons. Its first and second electrodes are connected to a DC circuit, with the first electrode at a positive potential and the second electrode grounded. The second electrode and the gate control electrode are connected to an adjustable DC circuit, with a protective resistor connected in series. The QLED's luminous efficiency or brightness is adjusted by regulating the voltage of the gate control electrode. Specifically, applying a positive voltage to the gate control electrode relative to the second electrode tends to increase the device's luminous efficiency; while applying a negative voltage to the gate control electrode relative to the second electrode tends to increase the device's brightness.

[0084] The principle behind this technology is as follows: Since the majority carriers in this device are electrons, the gate control electrode is located on the electron transport layer side. Applying a positive gate voltage creates a built-in electric field, reducing electron injection from the electron transport layer to the quantum dot emitting layer, thus preventing excess electrons from failing to recombine and improving luminous efficiency. Conversely, applying a negative gate voltage creates a built-in electric field that enhances electron carrier injection, increasing recombination speed and thus improving brightness.

[0085] Example 4

[0086] like Figures 6-7 As shown, based on the first embodiment of the present invention, the injection-free light-emitting device provided in the fourth embodiment of the present invention is a single-ended injection-free type, specifically employing electron injection-free technology.

[0087] The injection-free light-emitting unit is configured to include, in sequence, a first electrode, a hole transport / injection layer, a light-emitting material layer, an injection-free insulating layer, and a second electrode; the light-emitting material layer is a PN light-emitting layer, a quantum dot light-emitting layer, or an organic light-emitting layer; when the light-emitting material layer is a PN light-emitting layer, the light-emitting material layer is in a P-type region near the first electrode and in an N-type region near the second electrode.

[0088] like Figure 7 As shown, the device structure achieves the control of luminous brightness and luminous efficiency in the following ways.

[0089] (a) When the majority carriers of the light-emitting material layer are electron carriers and the gate control electrode is located on the side of the first electrode; wherein, the gate control electrode applies a positive potential relative to the first electrode to increase the hole carriers in the light-emitting material layer, so as to improve the luminous efficiency and luminous brightness of the injection-free light-emitting unit;

[0090] (b) when the majority carriers of the light-emitting material layer are hole-type carriers and the gate control electrode is located at the first electrode side; wherein the gate control electrode applies a negative potential to the first electrode to reduce the hole-type carriers in the light-emitting material layer, so as to improve the light-emitting efficiency of the non-injection light-emitting unit; the gate control electrode applies a positive potential to the first electrode to increase the hole-type carriers in the light-emitting material layer, so as to improve the light-emitting brightness of the non-injection light-emitting unit;

[0091] (c) when the majority carriers of the light-emitting material layer are hole-type carriers and the gate control electrode is located at the second electrode side; the gate control electrode applies a negative positive potential to the second electrode to increase the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the light-emitting efficiency and the light-emitting brightness of the non-injection light-emitting unit;

[0092] (d) when the majority carriers of the light-emitting material layer are electron-type carriers and the gate control electrode is located at the second electrode side; wherein the gate control electrode applies a negative potential to the second electrode to increase the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the light-emitting brightness of the non-injection light-emitting unit; the gate control electrode applies a positive potential to the second electrode to reduce the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the light-emitting efficiency of the non-injection light-emitting unit.

[0093] In addition, the bias power supply is an adjustable voltage power supply, and the voltage value of the bias power supply can be adjusted according to the actual application of each device. The bias power supply is adjusted according to the light-emitting brightness or the light-emitting efficiency requirement, so as to obtain a better light-emitting efficiency or a higher light-emitting brightness.

[0094] In addition, a current-limiting resistor can be further connected in series between the gate control electrode and the bias power supply loop, so as to avoid that the loop current is too large and the device is burned out.

[0095] It is worth mentioning that the gate control electrode can be arranged at the light-emitting side or the back light side of the device structure. Typically, the gate control electrode is arranged at the back light side of the device structure to reduce the loss of the gate control electrode on the light-emitting transmittance and improve the light-emitting brightness. In addition, the actual light-emitting angle can also be perpendicular to the side edge of the radial direction of the first electrode, the second electrode and the gate control electrode. The present application does not actually limit the light-emitting direction of the device.

[0096] The preferred embodiments of the present application have been described above in detail. It should be understood that modifications and variations to the present application can be affected by those skilled in the art without departing from the scope of the application. Accordingly, it is intended that all of the subject matter of the above description and the claims be interpreted to encompass all such modifications and changes.

Claims

1. A gate-controlled injectionless light emitting device structure, characterized by, The device structure comprises: a non-injection light-emitting unit, a gate insulating layer, and a gate control electrode; the gate insulating layer is arranged between the non-injection light-emitting unit and the gate control electrode; The non-injection light-emitting unit comprises: a light-emitting material layer, a first electrode arranged on both sides of the light-emitting material layer, a second electrode, a first dielectric layer arranged between the first electrode and the light-emitting material layer, and a second dielectric layer arranged between the second electrode and the light-emitting material layer; At least one of the first dielectric layer and the second dielectric layer is a non-injection insulating layer, and the rest is a carrier transport / injection layer; The gate control electrode is located on the side of the first electrode or the second electrode; During the operation of the device, the first electrode and the second electrode apply a first alternating current power source, which is used to power the non-injection light-emitting unit to emit light; the gate control electrode applies a bias power source relative to the first electrode and / or the second electrode, which is used to build an electric field to control the mobility of carriers in the non-injection light-emitting unit to adjust the light-emitting brightness or light-emitting efficiency of the non-injection light-emitting unit.

2. The grid-controlled injection-less light emitting device structure of claim 1, wherein, The non-injection light-emitting unit comprises in sequence: a first electrode, a non-injection insulating layer, a light-emitting material layer, a non-injection insulating layer, and a second electrode; the light-emitting material layer is a PN light-emitting layer, a quantum dot light-emitting layer, or an organic light-emitting layer; the light-emitting material layer is a P-type region adjacent to the first electrode and an N-type region adjacent to the second electrode; When the majority carriers of the light-emitting material layer are electron-type carriers and the gate control electrode is located on the side of the first electrode; wherein the gate control electrode applies a positive potential relative to the first electrode to increase the recombination amount of hole-type carriers in the light-emitting material layer, so as to improve the light-emitting brightness and light-emitting efficiency of the non-injection light-emitting unit; When the majority carriers of the light-emitting material layer are hole-type carriers and the gate control electrode is located on the side of the first electrode; wherein the gate control electrode applies a negative potential relative to the first electrode to reduce the recombination amount of the hole-type carriers in the light-emitting material layer, so as to improve the light-emitting efficiency of the non-injection light-emitting unit; the gate control electrode applies a positive potential relative to the first electrode to increase the hole-type carriers in the light-emitting material layer, so as to improve the light-emitting brightness of the non-injection light-emitting unit; When the majority carriers of the light-emitting material layer are hole-type carriers and the gate control electrode is located on the side of the second electrode; the gate control electrode applies a negative positive potential relative to the second electrode to increase the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the light-emitting efficiency and light-emitting brightness of the non-injection light-emitting unit; When the majority carriers of the light-emitting material layer are electron-type carriers and the gate regulating electrode is located at the second electrode side; wherein the gate regulating electrode applies a negative potential to the second electrode to increase the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the luminous brightness of the non-injection light-emitting unit; the gate regulating electrode applies a positive potential to the second electrode to reduce the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the luminous efficiency of the non-injection light-emitting unit.

3. The grid-controlled injection-less light emitting device structure of claim 1, wherein the grid electrode is formed of a material selected from the group consisting of: gold, silver, aluminum, platinum, and combinations thereof. The non-injection light-emitting unit is configured to sequentially include a first electrode, a non-injection insulating layer, a light-emitting material layer, an electron transport / injection layer, and a second electrode; or sequentially include a first electrode, a hole transport / injection layer, a light-emitting material layer, a non-injection insulating layer, and a second electrode; the light-emitting material layer is a PN light-emitting layer, a quantum dot light-emitting layer, or an organic light-emitting layer; when the light-emitting material layer is a PN light-emitting layer, the light-emitting material layer is a P-type region adjacent to the first electrode and an N-type region adjacent to the second electrode.

4. The grid-controlled injection-less light emitting device structure of claim 3, wherein the grid electrode is formed of a material having a work function of 2.5 eV or more. When the majority carriers of the light-emitting material layer are electron-type carriers and the gate regulating electrode is located at the first electrode side; wherein the gate regulating electrode applies a positive potential to the first electrode to increase the hole-type carriers in the light-emitting material layer, so as to improve the luminous efficiency and luminous brightness of the non-injection light-emitting unit.

5. The grid-controlled injection-less light emitting device structure of claim 3, wherein the grid electrode is formed of a material having a work function of 2.5 eV or more. When the majority carriers of the light-emitting material layer are hole-type carriers and the gate regulating electrode is located at the first electrode side; wherein the gate regulating electrode applies a negative potential to the first electrode to reduce the hole-type carriers in the light-emitting material layer, so as to improve the luminous efficiency of the non-injection light-emitting unit; the gate regulating electrode applies a positive potential to the first electrode to increase the hole-type carriers in the light-emitting material layer, so as to improve the luminous brightness of the non-injection light-emitting unit.

6. The grid-controlled injection-less light emitting device structure of claim 3, wherein the grid electrode is formed of a material selected from the group consisting of: indium tin oxide, indium zinc oxide, and aluminum zinc oxide. When the majority carriers of the light-emitting material layer are hole-type carriers and the gate regulating electrode is located at the second electrode side; the gate regulating electrode applies a negative potential to the second electrode to increase the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the luminous efficiency and luminous brightness of the non-injection light-emitting unit.

7. The gate-controlled injection-free light-emitting device structure as described in claim 3, characterized in that, When the majority carriers of the light-emitting material layer are electron-type carriers and the gate regulating electrode is located at the second electrode side; wherein the gate regulating electrode applies a negative potential to the second electrode to increase the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the luminous brightness of the non-injection light-emitting unit; the gate regulating electrode applies a positive potential to the second electrode to reduce the recombination amount of the electron-type carriers in the light-emitting material layer, so as to improve the luminous efficiency of the non-injection light-emitting unit.

8. The gate-controlled injection-free light-emitting device structure as described in claim 1, characterized in that, The bias power supply is an adjustable voltage power supply, which is adjusted according to the requirements of the luminous brightness or the luminous efficiency.

9. The gate-controlled injection-free light-emitting device structure as described in claim 1, characterized in that, A current-limiting resistor is further connected in series in the gate regulating electrode and the bias power supply circuit.

10. The gate-controlled injection-free light-emitting device structure as described in claim 1, characterized in that, The gate control electrode is disposed on a back side of the device structure opposite the light exit side.

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