Micro-LED pixel driving circuit and preparation method thereof, and display

Abstract

The invention provides a Micro-LED pixel driving circuit, a preparation method thereof and a display, and belongs to the technical field of display. The Micro-LED pixel driving circuit comprises a Micro-LED chip, a memristor and a transistor, the positive electrode of the Micro-LED chip is connected with the first electrode of the memristor and the drain electrode of the transistor, and the negative electrode of the Micro-LED chip is connected with a power supply low voltage VSS; the second electrode of the memristor is connected with a power supply voltage signal VDD, and the memristor is used for realizing a low resistance state under the condition that the voltage between the second electrode and the first electrode is positive voltage and realizing a high resistance state under the condition that the voltage between the second electrode and the first electrode is negative voltage; the source electrode of the transistor is connected with a data voltage signal Vdata, and the grid electrode of the transistor is connected with a scanning voltage signal Vscan. The pixel density can be improved, the display requirement of higher resolution can be met, and the power consumption of the pixel driving circuit can be effectively reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a Micro-LED pixel driving circuit, a preparation method thereof, and a display. Background Art

[0002] Current high-resolution microdisplay systems (such as AR / VR devices) place high demands on microlight-emitting diodes (Micro-LEDs) for ultra-high pixel density, low power consumption, and ease of manufacturing. Traditional active-matrix microlight-emitting diode (AM Micro-LED) displays typically use a combination of two thin-film transistors (TFTs) and a capacitor (a 2T1C pixel driver circuit) to drive pixels.

[0003] like Figure 1 As shown, the traditional 2T1C pixel driving circuit includes a Micro-LED chip, a storage capacitor C1, a switching transistor T1 and a driving transistor T2, wherein the positive electrode of the Micro-LED chip is connected to the drain of the driving transistor T2, one end of the storage capacitor C1 is connected to the drain of the switching transistor T1 and the gate of the driving transistor T2, the other end of the storage capacitor C1 is connected to the source of the driving transistor T2 and the power supply voltage signal VDD, and the source of the switching transistor T1 is connected to the data voltage signal V data The gate of the switching transistor T1 is connected to the scanning voltage signal V scan .

[0004] However, in the process of driving the Micro-LED chip to emit light for display, the traditional 2T1C pixel driver circuit is susceptible to leakage current in the storage capacitor, requiring regular refresh to maintain the capacitor charge. This frequent refresh operation will lead to increased dynamic power consumption. At the same time, to ensure the stability of the driving voltage, the long-term conduction of the driving transistor will also cause static power consumption. At high refresh rates and brightness control scenarios, the power consumption of the 2T1C pixel driver circuit is relatively high. In addition, the storage capacitor and driving transistor occupy a large amount of pixel area, which restricts the improvement of pixel density. Summary of the Invention

[0005] The present disclosure provides a Micro-LED pixel driving circuit and its preparation method, and a display, which can improve pixel density, meet the needs of higher-resolution displays, and effectively reduce the power consumption of the pixel driving circuit. The technical solution includes at least the following solutions: On the one hand, a Micro-LED pixel driving circuit is provided, including a Micro-LED chip, a memristor, and a transistor, wherein the positive electrode of the Micro-LED chip is connected to the first electrode of the memristor and the drain electrode of the transistor, and the negative electrode of the Micro-LED chip is connected to a low power supply voltage VSS; the second electrode of the memristor is connected to a power supply voltage signal VDD, and the memristor is used to achieve a low resistance state when the voltage between the second electrode and the first electrode is a positive voltage, and to achieve a high resistance state when the voltage between the second electrode and the first electrode is a negative voltage; the source electrode of the transistor is connected to a data voltage signal V data The gate of the transistor is connected to the scanning voltage signal V scan .

[0006] Optionally, the driving timing of the Micro-LED pixel driving circuit includes: an initial stage, a writing stage, a light emitting stage and an erasing stage; in the initial stage, the power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan In the writing phase, the power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan Both provide high potential, and the data voltage signal V data The potential of the data voltage signal VDD is 0.1V to 1V lower than the potential of the power supply voltage signal VDD; in the light-emitting stage, the power supply voltage signal VDD provides a high potential, and the data voltage signal V data and the scanning voltage signal V scan Provides a low potential; in the erase phase, the power supply voltage signal VDD provides a low potential, the data voltage signal V data and the scanning voltage signal V scan Provides high potential.

[0007] Optionally, the power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan All are provided by external timing controller.

[0008] Optionally, the memristor includes a lower electrode, a buffer layer, a resistive switching layer and an upper electrode stacked in sequence, the first electrode of the memristor is the lower electrode, and the second electrode of the memristor is the upper electrode.

[0009] Optionally, the material of the resistive switching layer includes HfO x , one of SrTiO3, GeTe and SbTe.

[0010] Optionally, the resistance of the memristor can be dynamically adjusted between 50Ω and 10GΩ.

[0011] Optionally, the transistor is a thin film transistor or a complementary metal oxide semiconductor transistor.

[0012] Optionally, the transistor is a thin film transistor, and the Micro-LED chip, the memristor and the transistor are monolithically integrated on the same substrate wafer.

[0013] On the other hand, a method for preparing a Micro-LED pixel driving circuit is provided, comprising: providing a Micro-LED chip; forming a memristor and a transistor, wherein the positive electrode of the Micro-LED chip is connected to the first electrode of the memristor and the drain of the transistor, the negative electrode of the Micro-LED chip is connected to a low power supply voltage VSS, the second electrode of the memristor is connected to a power supply voltage signal VDD, the memristor is configured to achieve a low resistance state when the voltage between the second electrode and the first electrode is positive, and to achieve a high resistance state when the voltage between the second electrode and the first electrode is negative, and the source electrode of the transistor is connected to a data voltage signal V data The gate of the transistor is connected to the scanning voltage signal V scan .

[0014] On the other hand, a display is provided, comprising at least one Micro-LED pixel driving circuit according to any one of the aforementioned methods.

[0015] The beneficial effects of the technical solutions provided by the embodiments of the present disclosure include at least: In the disclosed embodiments, a memristor is configured to work with a Micro-LED chip and a transistor to form a Micro-LED pixel driver circuit. This eliminates the need for the storage capacitor and driver transistors found in conventional 2T1C pixel driver circuits, simplifying the circuit structure and reducing footprint. This facilitates increased pixel density and accommodates higher-resolution display requirements. The positive electrode of the Micro-LED chip is connected to the first electrode of the memristor and the drain of the transistor, while the second electrode of the memristor is connected to a power supply voltage signal (VDD). The memristor can achieve a low-resistance state when the voltage between the second and first electrodes is positive, and a high-resistance state when the voltage between the second and first electrodes is negative. Furthermore, the memristor possesses multi-resistance state control capabilities under relatively low voltage conditions. Its resistance can be set using a simple low-voltage pulse, achieving the current control required for brightness adjustment of the Micro-LED chip. This significantly reduces the overall voltage drive requirements of the pixel driver circuit. The memristor also possesses non-volatility. Once a resistance state is written, it maintains that state without continuous power supply, eliminating the need for frequent refreshes. This effectively reduces the power consumption of the pixel driver circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] Figure 1 This is the circuit diagram of the traditional 2T1C pixel driving circuit; Figure 2 is a circuit diagram of a Micro-LED pixel driving circuit provided by an embodiment of the present disclosure; Figure 3 is a timing diagram of a Micro-LED pixel driving circuit provided by an embodiment of the present disclosure; Figure 4 is a structural diagram of a Micro-LED pixel driving circuit provided by an embodiment of the present disclosure; Figures 5 to 12 Schematic diagram of the preparation process of the Micro-LED pixel driving circuit provided by the embodiment of the present disclosure; Figure 13 This is a circuit diagram of a display provided by an embodiment of the present disclosure.

[0018] Reference numerals: 101: substrate; 102: first semiconductor layer; 103: light-emitting layer; 104: second semiconductor layer; 105: transparent conductive layer; 106: amorphous silicon; 107: polycrystalline silicon active layer; 108: passivation layer; 109: source electrode; 110: drain electrode; 111: first connecting electrode; 112: power line; 113: second connecting electrode; 114: gate electrode; 115: data line; 116: bridging layer; 117: lower electrode; 118: buffer layer; 119: resistive layer; 120: upper electrode. DETAILED DESCRIPTION

[0019] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by a person of ordinary skill in the art to which this disclosure pertains. The terms "first," "second," "third," and similar terms used in the patent specification and claims of this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish between different components. Similarly, terms such as "a" or "an" do not indicate a quantitative limitation, but rather indicate the presence of at least one. Terms such as "include" or "comprising" mean that the elements or objects preceding "include" or "comprising" encompass the elements or objects listed after "include" or "comprising," and their equivalents, and do not exclude other elements or objects. Terms such as "connected" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. "A and / or B" indicates three situations: A, B, and A and B.

[0020] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0021] Figure 2 : is a circuit diagram of a Micro-LED pixel driving circuit provided by an embodiment of the present disclosure. Figure 2 As shown, the Micro-LED pixel driving circuit includes a Micro-LED chip, a memristor M, and a transistor T. The positive electrode of the Micro-LED chip is connected to the first electrode of the memristor M and the drain of the transistor T, and the negative electrode of the Micro-LED chip is connected to the low power supply voltage VSS. The second electrode of the memristor M is connected to the power supply voltage signal VDD. The memristor M is used to achieve a low resistance state when the voltage between the second electrode and the first electrode is positive, and to achieve a high resistance state when the voltage between the second electrode and the first electrode is negative. The source electrode of the transistor T is connected to the data voltage signal V data , the gate of transistor T is connected to the scanning voltage signal V scan .

[0022] In the disclosed embodiments, a memristor M is configured to work with a Micro-LED chip and a transistor T to form a Micro-LED pixel driver circuit. This eliminates the need for the storage capacitor and driver transistor T found in conventional 2T1C pixel driver circuits, simplifying the circuit structure and reducing footprint. This facilitates increased pixel density and accommodates higher-resolution display requirements. The anode of the Micro-LED chip is connected to the first electrode of the memristor M and the drain of the transistor T, while the second electrode of the memristor M is connected to a power supply voltage signal VDD. The memristor M can achieve a low-resistance state when the voltage between the second and first electrodes is positive, and a high-resistance state when the voltage between the second and first electrodes is negative. Furthermore, the memristor M possesses multi-resistance state control capabilities at relatively low voltages. Its resistance can be set using a simple low-voltage pulse, achieving the current control required for brightness adjustment of the Micro-LED chip. This significantly reduces the overall voltage drive requirements of the pixel driver circuit. The memristor M also possesses non-volatility. Once a resistance state is written, it maintains that state without continuous power supply, eliminating the need for frequent refreshes. This effectively reduces the power consumption of the pixel driver circuit.

[0023] Figure 3 This is a timing diagram of the Micro-LED pixel driving circuit provided by the embodiment of the present disclosure. Figure 2 and Figure 3 The driving timing of the Micro-LED pixel driving circuit includes: initial stage, writing stage, light-emitting stage and erasing stage.

[0024] In the initial stage, the power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan All provide low potential. The Micro-LED chip, memristor M and transistor T are all in a non-working state.

[0025] In the writing phase, the power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan Both provide high potential, and the data voltage signal V data The potential of the memristor M is 0.1V to 1V lower than the potential of the power supply voltage signal VDD. When the transistor T is turned on, the voltage between the second electrode and the first electrode of the memristor M is the voltage between the power supply voltage signal VDD and the data voltage signal V data The voltage difference is 0.1V to 1V, which is a positive voltage. The memristor M is in a low resistance state and the Micro-LED chip is in an off state. In this writing phase, the resistance of the memristor M can be adjusted according to the power supply voltage signal VDD and the data voltage signal V dataThe actual voltage difference adjustment can be achieved by adjusting the voltage between the second pole and the first pole of the memristor M in the positive voltage range of 0.1V to 1V, so that the resistance of the memristor M can be finely set, and the current control required for brightness adjustment of the Micro-LED chip can be achieved in the next stage of light emission.

[0026] For example, in the writing phase, the potential of the power supply voltage signal VDD may be equal to the scanning voltage signal V scan potential, that is, the two signals provide a high potential with the same voltage.

[0027] In the light-emitting phase, the power supply voltage signal VDD provides a high potential, and the data voltage signal V data and the scanning voltage signal V scan A low potential is provided. Transistor T is turned off, memristor M remains in a low-resistance state, and the Micro-LED chip is in a light-emitting state. During this light-emitting phase, because the voltage between the second and first electrodes of memristor M remains positive and the pulse width and amplitude can be controlled, the resistance of memristor M during the light-emitting phase does not change significantly from the resistance set during the write phase. This allows for precise and stable adjustment of the Micro-LED chip's brightness using the resistance of memristor M.

[0028] In the erase phase, the power supply voltage signal VDD provides a low potential, and the data voltage signal V data and the scanning voltage signal V scan Provides a high potential. Transistor T is turned on, and the voltage between the second electrode and the first electrode of the memristor M is the low potential of the power supply voltage signal VDD and the data voltage signal V data The voltage difference of the high potential is negative voltage, the memristor M is in high resistance state and open circuit, and the Micro-LED chip is in the off state.

[0029] Optionally, the resistance of memristor M can be dynamically adjusted between 50Ω and 10GΩ. Covering this wide range, the multi-resistance-state characteristics of memristor M effectively replace the storage capacitor and pixel capacitance retention functions of the driver transistor in a traditional 2T1C pixel driver circuit. By varying the resistance state at different stages, the micro-LED chip can be driven to emit light for display. Furthermore, by precisely adjusting the resistance of memristor M, the brightness adjustment capability of the micro-LED chip can be enhanced, which helps improve the grayscale level of the display and thus enhance display performance.

[0030] For example, the power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan All are provided by external timing controller.

[0031] Figure 4Schematic diagram of the structure of the Micro-LED pixel driving circuit provided by the embodiment of the present disclosure. Figure 2 and Figure 4 The Micro-LED pixel driving circuit includes a Micro-LED chip, which includes a substrate 101, a first semiconductor layer 102, a light-emitting layer 103 and a second semiconductor layer 104 stacked in sequence. The Micro-LED chip has a mesa (MESA) structure extending from the surface of the second semiconductor layer 104 away from the light-emitting layer 103 to the first semiconductor layer 102.

[0032] For example, the substrate 101 may be a sapphire substrate.

[0033] For example, the first semiconductor layer 102 may be an n-type GaN layer, the light-emitting layer 103 may be a multi-quantum well active layer, and the second semiconductor layer 104 may be a p-type GaN layer.

[0034] Optionally, the Micro-LED chip further includes a transparent conductive layer 105, a passivation layer 108, a first connection electrode 111, and a second connection electrode 113. The transparent conductive layer is disposed on the second semiconductor layer 102. The passivation layer 108 is disposed on the transparent conductive layer 105 and the mesa structure. The passivation layer 108 covers the sidewalls of the first semiconductor layer 102, the light-emitting layer 103, the second semiconductor layer 104, and the transparent conductive layer 105. The passivation layer 108 has two electrical connection grooves that expose the first semiconductor layer 102 and the transparent conductive layer 105. The first connection electrode 111 is disposed in one electrical connection groove and connected to the first semiconductor layer 102, and the second connection electrode 112 is disposed in the other electrical connection groove and connected to the transparent conductive layer 105.

[0035] Exemplarily, the transparent conductive layer 105 may be an indium tin oxide (ITO) layer.

[0036] For example, the passivation layer 108 may be a SiO 2 passivation layer.

[0037] Exemplarily, the positive electrode of the Micro-LED chip is the first connection electrode 111, and the negative electrode of the Micro-LED chip is the second connection electrode 113. The first connection electrode 111 and the second connection electrode 113 are both made of metal.

[0038] Exemplarily, the Micro-LED pixel driving circuit also includes a memristor M, which includes a lower electrode 117, a buffer layer 118, a resistive layer 119 and an upper electrode 120 stacked in sequence, the first electrode of the memristor M is the lower electrode 117, and the second electrode of the memristor M is the upper electrode 120.

[0039] Optionally, the memristor M is disposed on the second connection electrode 113 of the Micro-LED chip, the lower electrode 117 is connected to the second connection electrode 113 , and the upper electrode 120 is used to connect to the power supply voltage signal VDD.

[0040] Optionally, the thickness of the lower electrode 117 and the upper electrode 120 is 50 nm to 100 nm. For example, the thickness of the lower electrode 117 and the upper electrode 120 can be 50 nm, 70 nm, or 100 nm.

[0041] Exemplarily, the materials of the lower electrode 117 and the upper electrode 120 are both metal materials. For example, the lower electrode 117 and the upper electrode 120 may each include at least one of Au, Ag, and Cu.

[0042] Optionally, the buffer layer 118 has a thickness of 5 nm to 20 nm. The thickness of the buffer layer 118 within this range can improve the high-resistance stability of the memristor M. For example, the thickness of the buffer layer 118 can be 5 nm, 10 nm, 15 nm, or 20 nm.

[0043] For example, the buffer layer 118 may be a SiO 2 buffer layer.

[0044] Optionally, the thickness of the resistive switching layer 119 is 30 nm to 100 nm. For example, the thickness of the resistive switching layer 119 can be 30 nm, 60 nm, or 100 nm.

[0045] Optionally, the material of the resistive layer 119 includes HfO x The resistive switching layer 119 is made of one of SrTiO3, GeTe and SbTe. The use of these materials can ensure that the memristor M has good memristive characteristics.

[0046] Exemplarily, the Micro-LED pixel driving circuit further includes a transistor T, which is a TFT or a complementary metal-oxide-semiconductor (CMOS) transistor.

[0047] Optionally, transistor T is a TFT, disposed on substrate 101 and located on one side of the Micro-LED chip. This means that the Micro-LED chip, memristor M, and transistor T are monolithically integrated on the same substrate wafer. This simplifies the fabrication process of the Micro-LED pixel driver circuit, eliminates the need for chip migration or transfer and pasting processes, and is suitable for wafer-level manufacturing, offering strong process compatibility and low fabrication costs.

[0048] Exemplarily, the transistor T includes a polysilicon active layer 107, a source 109, and a drain 110. The polysilicon active layer 107 is disposed on a substrate 101. The source 109 and the drain 110 are respectively disposed on both sides of the polysilicon active layer 107 and connected to the polysilicon active layer 107. The polysilicon active layer 107 can serve as a switching channel.

[0049] Exemplarily, the passivation layer 108 is further disposed on the polysilicon active layer 107, the source electrode 109, and the drain electrode 110. The passivation layer 108 also covers the sidewalls of the source electrode 109 and the drain electrode 110. The passivation layer 108 also has two electrical connection grooves exposing the source electrode 109 and the drain electrode 110. The second connection electrode 113 is further connected to the drain electrode 110 through one of the electrical connection grooves. The Micro-LED pixel driving circuit also includes a data line 115, which is disposed in another electrical connection groove and connected to the source electrode 109. The data line 115 is used to connect the data voltage signal V data .

[0050] For example, the data line 115 may be made of a metal material.

[0051] Exemplarily, the transistor T further includes a gate 114, which is disposed on the passivation layer 108 on the polysilicon active layer 107. The gate 114 is used to connect the scan voltage signal V scan .

[0052] For example, the gate 114 may be made of a metal material.

[0053] Exemplarily, the Micro-LED pixel driving circuit also includes a power line 112, which is arranged on the substrate 101 and is located on the side of the Micro-LED chip away from the transistor T. The power line 112 is connected to the first connection electrode 111 through the bridging layer 116. The power line 112 is used to connect to the low power supply voltage VSS.

[0054] For example, the power line 112 and the bridge layer 116 may be made of metal.

[0055] It should be noted that the materials of the above-mentioned film layers are only used as an example, and the specific material selection can be adjusted according to actual needs, and the present disclosure does not impose any restrictions on this.

[0056] The present disclosure also provides a method for preparing a Micro-LED pixel driving circuit. The method comprises the following steps: In step S1 , a Micro-LED chip is provided.

[0057] In step S2 , a memristor and a transistor are formed.

[0058] The positive electrode of the Micro-LED chip is connected to the first electrode of the memristor and the drain of the transistor. The negative electrode of the Micro-LED chip is connected to the low power supply voltage VSS. The second electrode of the memristor is connected to the power supply voltage signal VDD. The memristor is used to achieve a low resistance state when the voltage between the second electrode and the first electrode is positive, and to achieve a high resistance state when the voltage between the second electrode and the first electrode is negative. The source of the transistor is connected to the data voltage signal V data , the gate of the transistor is connected to the scanning voltage signal V scan .

[0059] It should be noted that the preparation method embodiment and the above-mentioned Micro-LED pixel driving circuit structure embodiment are based on the same inventive concept. The beneficial effects of the embodiment of the present disclosure can be found in the above-mentioned structural embodiment and will not be repeated here.

[0060] Figures 5 to 12 Schematic diagram of the preparation process of the Micro-LED pixel driving circuit provided by the embodiment of the present disclosure. Figures 4 to 12 , optionally, the preparation method comprises: The first step, such as Figure 5 As shown, a Micro-LED wafer is obtained, which includes a substrate 101 and epitaxial layers on the substrate 101, namely, a first semiconductor layer 102, a light-emitting layer 103 and a second semiconductor layer 104 stacked in sequence.

[0061] The second step is Figure 6 As shown, a 20 nm thick ITO film is deposited on the surface of the second semiconductor layer 104 by using methods such as plasma enhanced chemical vapor deposition (PECVD) to preliminarily form a transparent conductive layer 105 .

[0062] The third step, such as Figure 7 As shown, a terrace structure is prepared on a Micro-LED wafer using photolithography and dry etching technology, and etching is performed on one side of the epitaxial layer until it reaches the substrate 101.

[0063] The fourth step is as follows Figure 8 As shown, amorphous silicon 106 with a thickness of 100 nm is deposited on the substrate 101 using PECVD technology.

[0064] Step 5: Figure 8 and Figure 9 As shown, a thermal annealing dehydrogenation treatment is performed at 450°C, and the amorphous silicon 106 is converted into a polycrystalline silicon active layer 107 using XeCl excimer laser annealing technology. The wavelength of the XeCl excimer laser is 308nm, the pulse width is 40ns, and the energy density is 250mJ / cm2 ; Then a 500nm thick SiO2 passivation layer is deposited to initially form a passivation layer 108.

[0065] Step 6: Figure 9 and Figure 10 As shown, ion implantation technology was used to implant 2.5×10 15 cm -2 Boron ions of a certain dosage are self-alignedly implanted into the polysilicon active layer 107 to form a source 109 and a drain 110 ; then, a plurality of electrical connection trenches are prepared on the passivation layer 108 by photolithography and etching techniques for subsequent metal deposition.

[0066] Step 7: Figure 11 As shown, the first connection electrode 111 and the power line 112 are deposited on the first semiconductor layer and the substrate respectively by using a photolithography process and an electron beam evaporation process.

[0067] Step 8: Figure 12 As shown, the second connection electrode 113 , the gate electrode 114 , the data line 115 and the bridge layer 116 are respectively deposited by using a photolithography process and an electron beam evaporation process.

[0068] Step 9: Figure 4 As shown, a 100 nm thick Ag layer, a 20 nm thick SiO2 buffer layer, a 40 nm thick SbTe layer and a 100 nm thick Ag layer are sequentially deposited on the surface of the second connecting electrode 113 using a photolithography process and a deposition process to obtain a lower electrode 117, a buffer layer 118, a resistive layer 119 and an upper electrode 120, thereby forming a memristor.

[0069] Through the above steps 1 to 9, we can get Figure 4 The Micro-LED pixel driving circuit shown.

[0070] It should be noted that the above Figures 5 to 12 In the preparation method embodiment, the markings of the film materials only indicate Figure 4 The state of the corresponding film layer structure during the preparation process, the structure, material and setting position of each film layer in the final Micro-LED pixel driving circuit can be seen in Figure 4 Detailed description of the related structural embodiments is omitted here.

[0071] An embodiment of the present disclosure also provides a display comprising at least one Micro-LED pixel driving circuit of any one of the aforementioned types.

[0072] Figure 13 : is a circuit diagram of a display provided by an embodiment of the present disclosure. Figure 13 As shown, the display includes a plurality of aforementioned Micro-LED pixel driving circuits arranged in an array.

[0073] Optionally, the display may be a display of an AR / VR near-eye display device, a smart wearable device, a low-power display terminal or other device.

[0074] The above description is merely an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A Micro-LED pixel driving circuit, characterized in that: Including Micro-LED chips, memristors and transistors, The positive electrode of the Micro-LED chip is connected to the first electrode of the memristor and the drain of the transistor, and the negative electrode of the Micro-LED chip is connected to the low power voltage VSS; The second electrode of the memristor is connected to the power supply voltage signal VDD, and the memristor is used to realize a low resistance state when the voltage between the second electrode and the first electrode is a positive voltage, and realize a high resistance state when the voltage between the second electrode and the first electrode is a negative voltage; The source of the transistor is connected to the data voltage signal V data The gate of the transistor is connected to the scanning voltage signal V scan .

2. The Micro-LED pixel driving circuit according to claim 1, wherein: The driving timing of the Micro-LED pixel driving circuit includes: an initial stage, a writing stage, a light-emitting stage, and an erasing stage; In the initial stage, the power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan Both provide low potential; In the writing phase, the power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan Both provide high potential, and the data voltage signal V data The potential is lower than the potential of the power supply voltage signal VDD by 0.1V to 1V; In the light emitting phase, the power supply voltage signal VDD provides a high potential, and the data voltage signal V data and the scanning voltage signal V scan Provide low potential; In the erasing phase, the power supply voltage signal VDD provides a low potential, and the data voltage signal V data and the scanning voltage signal V scan Provides high potential.

3. The Micro-LED pixel driving circuit according to claim 2, wherein: The power supply voltage signal VDD, the data voltage signal V data and the scanning voltage signal V scan All are provided by external timing controller.

4. The Micro-LED pixel driving circuit according to claim 1, wherein: The memristor comprises a lower electrode, a buffer layer, a resistive switching layer and an upper electrode stacked in sequence. The first electrode of the memristor is the lower electrode, and the second electrode of the memristor is the upper electrode.

5. The Micro-LED pixel driving circuit according to claim 4, wherein: The material of the resistive layer includes HfO x , one of SrTiO3, GeTe and SbTe.

6. The Micro-LED pixel driving circuit according to any one of claims 1 to 5, wherein: The resistance of the memristor can be dynamically adjusted from 50Ω to 10GΩ.

7. The Micro-LED pixel driving circuit according to any one of claims 1 to 5, wherein: The transistor is a thin film transistor or a complementary metal oxide semiconductor transistor.

8. The Micro-LED pixel driving circuit according to claim 7, wherein: The transistor is a thin film transistor, and the Micro-LED chip, the memristor and the transistor are monolithically integrated on the same substrate wafer.

9. A method for preparing a Micro-LED pixel driving circuit, characterized in that: include: Providing a Micro-LED chip; A memristor and a transistor are formed, wherein the positive electrode of the Micro-LED chip is connected to the first electrode of the memristor and the drain of the transistor, the negative electrode of the Micro-LED chip is connected to the low power supply voltage VSS, the second electrode of the memristor is connected to the power supply voltage signal VDD, and the memristor is used to achieve a low resistance state when the voltage between the second electrode and the first electrode is a positive voltage, and to achieve a high resistance state when the voltage between the second electrode and the first electrode is a negative voltage. The source electrode of the transistor is connected to the data voltage signal V data The gate of the transistor is connected to the scanning voltage signal V scan .

10. A display, characterized in that: The device comprises at least one Micro-LED pixel driving circuit according to any one of claims 1 to 8.

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