阅读说明：本技术 基于Micro-LED的片上传感集成装置 (On-chip sensing integrated device based on Micro-LED ) 是由 郭小军 韩磊 唐伟 李骏 于 2021-09-02 设计创作，主要内容包括：本发明涉及一种基于Micro-LED的片上传感集成装置。所述基于Micro-LED的片上传感集成装置包括：衬底；Micro-LED芯片,位于所述衬底上,包括沿垂直于所述衬底的方向依次叠置的N-GaN层、多量子阱层、P-GaN层和芯片阳极；第一封装层,覆盖所述衬底并包覆所述Micro-LED芯片；功能传感结构,位于所述第一封装层上,且与所述Micro-LED芯片错开设置,所述功能传感结构包括光敏有机薄膜晶体管、光电二极管中的一种或者两者的组合,所述光敏有机薄膜晶体管和所述光电二极管的制程温度均低于200℃；第二封装层,至少包覆所述功能传感结构。本发明免去了巨量转移及键结工艺所带来的良率、工艺复杂度、成本等问题。(The invention relates to an on-chip sensing integrated device based on a Micro-LED. The Micro-LED-based on-chip sensing integrated device comprises: a substrate; the Micro-LED chip is positioned on the substrate and comprises an N-GaN layer, a multi-quantum well layer, a P-GaN layer and a chip anode which are sequentially overlapped along the direction vertical to the substrate; the first packaging layer covers the substrate and coats the Micro-LED chip; the functional sensing structure is positioned on the first packaging layer and staggered with the Micro-LED chip, the functional sensing structure comprises one or a combination of a photosensitive organic thin film transistor and a photodiode, and the processing temperature of the photosensitive organic thin film transistor and the photodiode is lower than 200 ℃; and the second packaging layer at least covers the functional sensing structure. The invention avoids the problems of yield, process complexity, cost and the like caused by a huge transfer and bonding process.)

1. A Micro-LED-based on-chip sensing integrated device is characterized by comprising:

a substrate;

the Micro-LED chip is positioned on the substrate and used as a backlight source of the Micro-LED-based on-chip sensing integrated device, and comprises a buffer layer, an N-GaN layer, a multi-quantum well layer, a P-GaN layer and a chip anode which are sequentially superposed along the direction vertical to the substrate;

the first packaging layer covers the substrate and coats the Micro-LED chip;

the functional sensing structure is positioned on the first packaging layer and staggered with the Micro-LED chip, the functional sensing structure comprises one or a combination of a photosensitive organic thin film transistor and a photodiode, the photosensitive organic thin film transistor comprises a gate electrode, a dielectric layer, a source electrode, a drain electrode and an organic semiconductor layer, the photodiode comprises a diode anode, a hole transmission layer, an active layer, an electron transmission layer and a diode cathode, and the processing temperatures of the photosensitive organic thin film transistor and the photodiode are lower than 200 ℃;

and the second packaging layer at least covers the functional sensing structure.

2. A Micro-LED based on-chip sensing integrated device according to claim 1, wherein the functional sensing structure comprises the photosensitive organic thin film transistor and the photodiode;

the photosensitive organic thin film transistor and the photodiode are electrically connected.

3. A Micro-LED based on-chip sensing integrated device according to claim 2, wherein said photodiode is located above said photosensitive organic thin film transistor in a direction along said substrate towards said functional sensing structure; the Micro-LED-based on-chip sensing integrated device further comprises:

a via hole extending in a direction perpendicular to the substrate, one end of the via hole exposing the photosensitive organic thin film transistor and the other end of the via hole thin-film the photodiode;

and the filling layer is filled in the through hole and is used for electrically connecting the photosensitive organic thin film transistor and the photodiode.

4. A Micro-LED based on-chip sensing integrated device according to claim 1, wherein the photosensitive organic thin film transistor is a bottom gate bottom contact type structure, a bottom gate top contact type structure, a top gate top contact type structure, or a top gate bottom contact type structure.

5. A Micro-LED based on-chip sensing integrated device according to claim 1, wherein the organic semiconductor layer in the photosensitive organic thin film transistor is a p-type organic semiconductor layer or an n-type organic semiconductor layer.

6. A Micro-LED based on-chip sensing integrated device according to claim 1, wherein the dielectric layer in the photosensitive organic thin film transistor is one of an inorganic dielectric layer, an organic dielectric layer or a combination of both.

7. A Micro-LED based on-chip sensing integrated device according to claim 1, wherein the first and second encapsulation layers are each an organic encapsulation layer, an inorganic encapsulation layer, or a hybrid encapsulation layer comprising organic and inorganic materials.

8. The Micro-LED based on-chip sensing integrated device according to claim 1, wherein the hole transport layer in the photodiode is made of MoO₃、WO₃、V₂O₅NiO, graphene oxide or PEDOT PSS.

9. The Micro-LED based on-chip sensing integrated device according to claim 1, wherein the material of the electron transport layer in the photodiode is ZnO, TiO₂、Cs₂CO₃Ca, Al, PFN or PNDI-1 Th.

10. A Micro-LED based on-chip sensing integrated device according to claim 1, wherein the material of the active layer in the photodiode is perovskite, ZcPc-Alq₃Pentacene, C60, F8BT-PDI, CNT-C60, P3HT-F8TBT, P3HT-ICBA, P3HT-PC₆₁BM or PTB7-PC₇₁BM。

Technical Field

The invention relates to the technical field of integrated circuit manufacturing, in particular to an on-chip sensing integrated device based on Micro-LEDs.

Background

Micro-LED (Micro light emitting diode) refers to a novel display technology in which the size of an LED chip is further miniaturized so that the size of a single LED chip reaches 1 μm to 10 μm. Compared with the traditional Liquid Crystal Display (LCD) technology and the Organic Light Emitting Diode (OLED) display technology, the Micro-LED has higher brightness, contrast and luminous efficiency, higher response speed, lower power consumption and longer display life, and is expected to be applied to the fields of high-performance display and sensing.

Different from the display of the traditional AMOLED (active matrix organic light emitting diode) and the AMLCD (active matrix liquid crystal display), the Micro-LED epitaxial growth has higher requirements on the thermal expansion coefficient, the lattice parameter and the like of a substrate material, so that the Micro-LED chip is difficult to prepare on the TFT backboard; in addition, the existing TFT technology (amorphous silicon TFT, low-temperature polysilicon TFT, oxide TFT) needs higher process temperature (more than 350 ℃), and the TFT backboard is difficult to be prepared on the Micro-LED chip by a monolithic integration mode.

Therefore, the integration of the TFT backplane and the Micro-LED chips is mostly realized in the industry by using bulk transfer and bonding, and the bulk transfer transfers the LED chips from the Micro-LED epitaxy to the backplane in batch by using laser transfer, roller transfer, elastic film transfer, electrostatic adsorption, electromagnetic force transfer, etc., but the method has significant defects in yield, efficiency, process complexity and production cost, and is difficult to meet the requirements of high-performance display and sensing; bonding techniques, including chip-level bonding, epitaxial-level bonding, and thin-film transfer, present certain challenges in terms of cost, substrate size, and pitch adjustability.

Therefore, it is an urgent technical problem to overcome the challenges of high manufacturing cost, low yield and low production efficiency caused by the huge transfer and bonding processes of the conventional LED chips.

Disclosure of Invention

The invention provides a Micro-LED-based on-chip sensing integrated device, which is used for solving the problems of high preparation cost, low yield, low production efficiency and the like caused by the traditional LED chip mass transfer and bonding process.

In order to solve the above problems, the present invention provides a Micro-LED based on-chip sensing integrated device, comprising:

a substrate;

the Micro-LED chip is positioned on the substrate and used as a backlight source of the Micro-LED-based on-chip sensing integrated device, and comprises a buffer layer, an N-GaN layer, a multi-quantum well layer, a P-GaN layer and a chip anode which are sequentially superposed along the direction vertical to the substrate;

the first packaging layer covers the substrate and coats the Micro-LED chip;

the functional sensing structure is positioned on the first packaging layer and staggered with the Micro-LED chip, the functional sensing structure comprises one or a combination of a photosensitive organic thin film transistor and a photodiode, the photosensitive organic thin film transistor comprises a gate electrode, a dielectric layer, a source electrode, a drain electrode and an organic semiconductor layer, the photodiode comprises a diode anode, a hole transmission layer, an active layer, an electron transmission layer and a diode cathode, and the processing temperatures of the photosensitive organic thin film transistor and the photodiode are lower than 200 ℃;

and the second packaging layer at least covers the functional sensing structure.

Optionally, the functional sensing structure comprises the photosensitive organic thin film transistor and the photodiode;

the photosensitive organic thin film transistor and the photodiode are electrically connected.

Optionally, the photodiode is located above the photosensitive organic thin film transistor in a direction along the substrate toward the functional sensing structure; the Micro-LED-based on-chip sensing integrated device further comprises:

a via hole extending in a direction perpendicular to the substrate, one end of the via hole exposing the photosensitive organic thin film transistor and the other end of the via hole thin-film the photodiode;

and the filling layer is filled in the through hole and is used for electrically connecting the photosensitive organic thin film transistor and the photodiode.

Optionally, the photosensitive organic thin film transistor is a bottom-gate bottom-contact type structure, a bottom-gate top-contact type structure, a top-gate top-contact type structure, or a top-gate bottom-contact type structure.

Optionally, the organic semiconductor layer in the photosensitive organic thin film transistor is a p-type organic semiconductor layer or an n-type organic semiconductor layer.

Optionally, the dielectric layer in the photosensitive organic thin film transistor is one of an inorganic dielectric layer and an organic dielectric layer, or a combination of the two.

Optionally, the first encapsulation layer and the second encapsulation layer are both an organic encapsulation layer, an inorganic encapsulation layer, or a hybrid encapsulation layer formed by an organic material and an inorganic material.

Optionally, the hole transport layer in the photodiode is made of MoO₃、WO₃、V₂O₅NiO, graphene oxide or PEDOT PSS.

Optionally, the electron transport layer in the photodiode is made of ZnO or TiO₂、Cs₂CO₃Ca, Al, PFN or PNDI-1 Th.

Optionally, the material of the active layer in the photodiode is perovskite, ZCPc-Alq₃Pentacene, C₆₀、F8BT-PDI、CNT-C60、P3HT-F8TBT、P3HT-ICBA、P3HT-PC₆₁BM or PTB7-PC71 BM.

According to the Micro-LED-based on-chip sensing integrated device, the photosensitive organic thin film transistor, the photodiode or the functional circuit thereof are prepared on the first packaging layer of the Micro-LED chip in a single chip integration mode by utilizing the lower process temperature (less than 200 ℃) of the photosensitive organic thin film transistor and the photodiode. Because the whole process is completed on the same substrate from bottom to top, the problems of yield, process complexity, cost and the like caused by a huge transfer and bonding process are avoided, and the integrated application based on the Micro-LED technology is favorably realized.

Drawings

FIG. 1 is a schematic structural diagram of an on-chip sensing integrated device based on Micro-LEDs in the embodiment of the invention;

FIGS. 2A-2D are schematic diagrams of four structures of a photosensitive organic thin film transistor in accordance with an embodiment of the present invention;

FIG. 3A is a schematic structural diagram of a bottom-gate bottom-contact structure-based photosensitive organic thin film transistor integrated with a Micro-LED chip according to an embodiment of the present invention;

FIG. 3B is a schematic structural diagram of a bottom-gate top-contact structure-based photosensitive organic thin film transistor integrated with a Micro-LED chip in an embodiment of the present invention;

FIGS. 4A-4B are schematic diagrams of two configurations of a photodiode in accordance with embodiments of the present invention;

FIG. 5A is a schematic structural diagram of the photodiode of FIG. 4A integrated with a Micro-LED chip;

FIG. 5B is a schematic structural diagram of the photodiode and Micro-LED chip of FIG. 4B integrated together;

FIG. 6A is a circuit diagram of a Micro-LED based on-chip sensing integrated device according to an embodiment of the present invention;

FIG. 6B is a circuit schematic of a single pixel within the dashed line box of FIG. 6A;

FIG. 7 is a schematic structural view of the integration of a photosensitive organic thin film transistor, a photodiode, and a Micro-LED chip in an embodiment of the present invention.

Detailed Description

The following describes in detail a specific embodiment of the Micro-LED based on-chip sensing integrated device provided by the present invention with reference to the accompanying drawings.

The present invention provides a Micro-LED based on-chip sensing integrated device, wherein FIG. 1 is a schematic structural diagram of a Micro-LED based on-chip sensing integrated device in a specific embodiment of the present invention, FIGS. 2A-2D are schematic structural diagrams of a photosensitive organic thin film transistor in a specific embodiment of the present invention, FIG. 3A is a schematic structural diagram of a photosensitive organic thin film transistor based on a bottom-gate bottom-contact structure and a Micro-LED chip in a specific embodiment of the present invention, FIG. 3B is a schematic structural diagram of a photosensitive organic thin film transistor based on a bottom-gate top-contact structure and a Micro-LED chip in a specific embodiment of the present invention, FIGS. 4A-4B are schematic structural diagrams of a photodiode in a specific embodiment of the present invention, FIG. 5A is a schematic structural diagram of a photodiode in FIG. 4A and a Micro-LED chip in an integrated manner, fig. 5B is a schematic structural diagram of the photodiode and the Micro-LED chip in fig. 4B, fig. 6A is a circuit diagram of a Micro-LED-based on-chip sensing integrated device in the embodiment of the present invention, fig. 6B is a schematic circuit diagram of a single pixel in a dashed line frame in fig. 6A, and fig. 7 is a schematic structural diagram of the photo organic thin film transistor, the photodiode, and the Micro-LED chip in the embodiment of the present invention. . As shown in fig. 1, fig. 2A to 2D, fig. 4A to 4B, fig. 5A to 5B, fig. 6A to 6B, and fig. 7, the Micro-LED based on-chip sensing integrated device includes:

a substrate 100;

the Micro-LED chip 200 is positioned on the substrate 100 and used as a backlight light source of the Micro-LED-based on-chip sensing integrated device, and the Micro-LED chip 200 comprises a buffer layer 1100, an N-GaN layer 1200, a multi-quantum well layer 1300, a P-GaN layer 1400 and a chip anode 1500 which are sequentially stacked along a direction perpendicular to the substrate 100;

a first encapsulation layer 300 covering the substrate 100 and encapsulating the Micro-LED chip 200;

a functional sensing structure 400, which is located on the first encapsulation layer 300 and is staggered from the Micro-LED chip 200, wherein the functional sensing structure 300 includes one or a combination of a photosensitive organic thin film transistor and a photodiode, the photosensitive organic thin film transistor includes a gate electrode 1700, a dielectric layer 1800, a source electrode 1901, a drain electrode 1902 and an organic semiconductor layer 2000, the photodiode includes a diode anode 3000, a hole transport layer 3100, an active layer 3200, an electron transport layer 3300 and a diode cathode 3400, and the process temperatures of the photosensitive organic thin film transistor and the photodiode are both lower than 200 ℃;

and a second packaging layer 500 at least covering the functional sensing structure 400.

Specifically, the substrate 100 may be selected from a sapphire substrate, a silicon substrate, a GaN substrate, a silicon carbide substrate, or a zinc oxide substrate. A buffer layer 1100 may be further disposed on the substrate 100, and the Micro-LED chip 200 is prepared on the buffer layer 1100 through epitaxial growth. The buffer layer 1100 is used to form a better lattice match and thermal expansion coefficient match with the epitaxially grown thin film, and optionally SiO may be used₂A material to form the buffer layer 1100. The Micro-LED chip 200 comprises from bottom to top: an N-GaN layer 1200, a multiple quantum well layer (MQW)1300, a P-GaN layer 1400, and a chip anode 1500. The material of the chip anode 1500 may be metal, metal oxide, or metal nanowire. Wherein the metal is gold, silver, copper, aluminum or nickel, and the metal oxide is indium tin oxide or fluorine-doped tin oxide. Preferably, the chip anode 1500 is formed using a high light transmittance electrode material, such as indium tin oxide.

In the Micro-LED-based on-chip sensing integrated device, the Micro-LED chip 200 is used as a backlight source, and the functional sensing structure 400 is used for realizing optical sensing. The photosensitive organic thin film transistor and/or the photodiode in the functional sensing structure 400 may be fabricated on the first encapsulation layer 300 after the epitaxial growth process of the Micro-LED chip 200 is completed. The functional sensing structure 400 further comprises functional circuitry for implementing the photo-sensing function of the photosensitive organic thin film transistor and/or the photodiode. The preparation processes of the photosensitive organic thin film transistor, the photodiode and the functional circuit thereof are all low-temperature processes, and the temperature for implementing all the processes of the photosensitive organic thin film transistor, the photodiode and the functional circuit thereof needs to be lower than 200 ℃. For example, the photosensitive organic thin film transistor, the photodiode and the functional circuit thereof may be fabricated by a vacuum process or a solution process, and preferably, by a low temperature solution process. The photosensitive organic thin film transistor refers to an Organic Thin Film Transistor (OTFT) having a photosensitive characteristic.

The first encapsulation layer 300 is located on the chip anode 1500 of the Micro-LED chip 200, and covers the substrate 100 and covers the Micro-LED chip 200. The second packaging layer 500 is located on the functional sensing structure 400 and at least covers the functional sensing structure 400. In one example, the second packaging layer 500 encapsulates the functional sensing structure 400 and covers the first packaging layer 300.

Optionally, the first encapsulation layer 300 and the second encapsulation layer 500 are both organic encapsulation layers, inorganic encapsulation layers, or hybrid encapsulation layers formed by organic materials and inorganic materials. In one example, the inorganic encapsulation layer may be SiO₂、SiN_xAnd an inorganic dielectric layer film, and the organic encapsulation layer may be an organic dielectric layer film (e.g., Parylene or CYTOP).

The materials of the first encapsulation layer 300 and the second encapsulation layer 500 may be both encapsulation materials with high light transmittance, so as to realize sensing of optical signals. The high light transmittance in this embodiment means a light transmittance of 90% or more.

Optionally, the functional sensing structure 400 includes the photosensitive organic thin film transistor and the photodiode;

the photosensitive organic thin film transistor and the photodiode are electrically connected.

Optionally, the photodiode is located above the photosensitive organic thin film transistor in a direction along the substrate 100 towards the functional sensing structure 400; the Micro-LED-based on-chip sensing integrated device further comprises:

a via hole extending in a direction perpendicular to the substrate 200, one end of the via hole exposing the photosensitive organic thin film transistor and the other end of the via hole thin-film the photodiode;

and a filling layer 700 filled in the via hole for electrically connecting the photosensitive organic thin film transistor and the photodiode.

Specifically, the first package layer 300 and the second package layer 500 may further have an interconnection microstructure including a via for electrical connection and electrode lead-out inside the functional sensing structure 400. The via hole can be realized by adopting methods such as laser, dry etching and the like. In one example, the via is formed using a dry etch process. The interconnect microstructure may include a via and the fill layer 700 filled in the via. The material of the filling layer 700 may be a low resistance material. For example, the material of the filling layer 700 is one or a combination of two or more of a conductive polymer, a conductive paste of metal and carbon base, a conductive polymer, a carbon-based conductive substance, a metal oxide, a metal nanowire, a metal, and a conductive elastic material doped with metal oxide nanoparticles, wherein the conductive polymer is poly (3, 4-ethylenedioxythiophene) -poly (styrenesulfonic acid), polystyrenesulfonic acid, polyaniline, polythiophene, or polypyrrole, the pH value of the conductive polymer is acidic or neutral, the carbon-based conductive substance is single-layer or multi-layer graphene, graphite, carbon black, single-wall or multi-wall carbon nanotube, the metal is gold, silver, copper, aluminum, or nickel, and the metal oxide is indium tin oxide or fluorine-doped tin oxide.

Optionally, the photosensitive organic thin film transistor is a bottom-gate bottom-contact type structure (as shown in fig. 2A), a bottom-gate top-contact type structure (as shown in fig. 2B), a top-gate top-contact type structure (as shown in fig. 2C), or a top-gate bottom-contact type structure (as shown in fig. 2D).

Specifically, when the photosensitive organic thin film transistor is used as a light sensing device in the Micro-LED-based on-chip sensing device, a bottom-gate bottom-contact type structure or a bottom-gate top-contact type structure is preferably adopted. When the photosensitive organic thin film transistor is used as a switching device in the Micro-LED-based on-chip sensing device, a bottom-gate bottom-contact type structure or a top-gate bottom-contact type structure is preferably adopted.

Optionally, the organic semiconductor layer 2000 in the photosensitive organic thin film transistor is a p-type organic semiconductor layer or an n-type organic semiconductor layer.

Optionally, the dielectric layer 1800 in the photosensitive organic thin film transistor is one of an inorganic dielectric layer and an organic dielectric layer, or a combination of the two.

In particular toIn other words, the material of the gate electrode 1700 in the photosensitive organic thin film transistor may be a metal material (e.g., gold, silver, copper, or aluminum), a low-resistivity oxide material (e.g., indium tin oxide, etc.). Preferably, the material of the gate electrode 1700 is a low-resistivity material with a higher light reflection capability. The dielectric layer 1800 in the photosensitive organic thin film transistor may be an inorganic dielectric layer (e.g., a material of SiO)₂、SiN_xOr Al₂O₃) An organic dielectric layer (e.g. the material Parylene, ES2110, CYTOP (perfluorocyclic polymer), or PVDF (polyvinylidene fluoride)). In one example, the dielectric layer 1800 is preferably an organic dielectric layer. The source electrode 1901 and the drain electrode 1902 may both be metal electrodes. For example, for a p-type photosensitive organic thin film transistor, a high work function metal electrode is preferably selected, such as: electrode materials such as gold and platinum; for n-type photosensitive organic thin film transistors, low work function metal electrodes are preferred, such as: electrode materials such as aluminum and silver. The source electrode 1901 and the drain electrode 1902 can be deposited by a vacuum process (e.g., evaporation, sputtering, etc.) or a solution process (e.g., screen printing, ink jet printing, etc.).

The material of the organic semiconductor layer 2000 may be an organic small molecule semiconductor, such as: TIPS-Pentacene, C₈-BTBT, DNTT, etc.; and may also be a polymeric semiconductor material such as: c₁₆IDTBT, PTAA, etc.; it may also be a mixed component of a small molecule semiconductor and a polymer semiconductor. The organic semiconductor layer 2000 may be prepared by a vacuum process (evaporation process) or a solution process, and preferably, may be prepared by a low-temperature solution process. Wherein, the solution method process comprises the following steps: blade coating, slot coating, ink jet printing, spin coating, drop coating, roll-to-roll coating.

Optionally, the material of the hole transport layer 3100 in the photodiode is MoO₃、WO₃、V₂O₅NiO, graphene oxide or PEDOT PSS.

Optionally, the electron transport layer in the photodiode is made of ZnO or TiO₂、Cs₂CO₃、Ca、Al、PFN or PNDI-1 Th.

Optionally, the material of the active layer 3200 in the photodiode is perovskite, ZcPc-Alq₃Pentacene, C₆₀、F8BT-PDI、CNT-C60、P3HT-F8TBT、P3HT-ICBA、P3HT-PC₆₁BM or PTB7-PC₇₁BM。

Specifically, the material of the diode anode 300 in the photodiode may be selected from metal, metal oxide, metal nanowire, and the like, the metal is gold, silver, copper, aluminum, nickel, and the like, the metal oxide is indium tin oxide, fluorine-doped tin oxide, and the like, and preferably, a high work function metal material, such as gold, platinum, and the like, is used. The electron transport layer 3300 can be made of ZnO or TiO₂、Cs₂CO₃Ca, Al, PFN or PNDI-1Th, etc. The material of the diode cathode 3400 may be metal, metal oxide, metal nanowire, or the like, the metal may be gold, silver, copper, aluminum, nickel, or the like, the metal oxide may be indium tin oxide or fluorine-doped tin oxide, or the like, and preferably, a metal material with a low work function, such as silver, aluminum, or the like, is used.

Fig. 6A is a block diagram of an array formed by m × n pixel units in the Micro-LED-based on-chip sensing integrated device, and fig. 6B is a circuit schematic diagram of one pixel unit. In the structure shown in fig. 6A and 6B, each of the pixel units includes the Micro-LED chip 200, and the functional sensing structure 400 includes the photosensitive organic thin film transistor and the photodiode. Wherein the photodiode operates in a forward bias state or a reverse bias state. Preferably, the photodiode operates in a reverse-biased state. If the photodiode operates in a reverse bias state and the photosensitive organic thin film transistor is a p-type photosensitive organic thin film transistor, the diode cathode 3400 of the photodiode is connected to the drain electrode 1902 of the photosensitive organic thin film transistor. If the photosensitive organic thin film transistor is an n-type photosensitive organic thin film transistor, the diode cathode 3400 of the photodiode is connected to the source electrode 1901 of the photosensitive organic thin film transistor.

Each one of which isThe pixel units respectively comprise one Micro-LED chip 200, the chip cathodes of all the Micro-LED chips 200 in the array are grounded, and the chip anodes 1500 of all the Micro-LED chips 200 are in short circuit to apply an anode voltage signal V_anodeFor providing a backlight source. The gate electrodes 1700 of all the photosensitive organic thin film transistors of each row in the array are shorted together by applying an external voltage signal V_scanTo control the on and off of the photosensitive organic thin film transistors in each row. The source electrodes 1901 of the photosensitive organic thin film transistors of each column in the array are shorted together to output a sense current signal I_readout. The diode anode 3000 of each of the photodiodes in the array is shorted together and connected to GND (ground).

FIG. 7 is a schematic structural diagram of a photosensitive organic thin film transistor, a reverse biased photodiode and a Micro-LED chip integration based structure. As shown in fig. 7, the photosensitive organic thin film transistor and the photodiode are both located above the first encapsulation layer 300, and the photodiode is stacked above the photosensitive organic thin film transistor in a direction along the substrate 100 toward the Micro-LED chip 200. In order to isolate the photosensitive organic thin film transistor and the photodiode, an intermediate layer 2100 is further disposed between the photosensitive organic thin film transistor and the photodiode. The material of the intermediate layer 2100 may be an inorganic dielectric layer material (SiO)₂,SiN_x,Al₂O₃Etc.), or organic dielectric layer materials (Parylene, ES2110, CYTOP, etc.). The intermediate layer 2100 has a via hole penetrating through the intermediate layer 2100 in a direction perpendicular to the substrate 100, and the filling layer 700 is filled in the via hole to electrically connect the diode cathode 3400 of the photodiode and the drain electrode 1902 of the photosensitive organic thin film transistor. In the structure shown in fig. 7, the photosensitive organic thin film transistor serves only as a switching device, and the photodiode serves as a photo-sensing device. In order to effectively shield an external light source, the photosensitive organic thin film transistor preferably employs a top-gate bottom-contact type structure. The gridThe material of the electrode 1700 is preferably an electrode material having a high reflection property or a high light absorption property.

In the Micro-LED-based on-chip sensing integrated device provided by the specific embodiment, the photosensitive organic thin film transistor, the photodiode or a functional circuit thereof is prepared on the first packaging layer of the Micro-LED chip in a monolithic integration mode by utilizing the lower process temperature (< 200 ℃) of the photosensitive organic thin film transistor and the photodiode. Because the whole process is completed on the same substrate from bottom to top, the problems of yield, process complexity, cost and the like caused by a huge transfer and bonding process are avoided, and the integrated application based on the Micro-LED technology is favorably realized.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.