High-density stretchable organic opto-transistor array and preparation method and application thereof

Abstract

The invention discloses a high-density stretchable organic opto-transistor array and a preparation method and application thereof. The high-density stretchable organic opto-transistor array is an organic opto-transistor based on a polymer film under a nanometer confinement. The organic opto-transistor adopts a top gate top contact structure, a top gate bottom contact structure, a bottom gate top contact structure or a bottom gate bottom contact structure, and comprises a stretchable substrate, a stretchable insulating layer, a stretchable polymer semiconductor layer, a stretchable gate electrode, a stretchable source microelectrode layer and a stretchable drain microelectrode layer. Wherein the stretchable polymer semiconductor layer is a nano-confinement polymer film, and the nano-confinement polymer film serves as a photosensitive layer and a semiconductor layer at the same time and directly participates in carrier transport while inducing photons. The high-density organic opto-transistor array has high-sensitivity, low-voltage and low-dose X-ray detection capability, high stretchability and device uniformity, can be directly attached to the surface or the interior of a complex object, and can obtain a high-definition detection result in a relatively low radiation dose and extremely short time.

Description

Technical Field

[0001] The present invention belongs to the field of flexible photoelectric detection technology, and relates to a high-density intrinsically stretchable organic phototransistor array and a preparation method and application thereof, and in particular to a method for preparing and integrating high-resolution stretchable microelectrodes assisted by a transferable interface method, and its application in high-sensitivity X-ray detection and scalable imaging technology. Background Art

[0002] Flexible photodetection and imaging technologies are crucial for the development of next-generation bioelectronic devices, including wearable and implantable monitoring devices, advanced medical imaging systems, and intelligent biomimetic robots. Modern digital imaging technology mainly relies on highly sensitive photodetectors, such as silicon-based flat-panel detectors, scintillator-type flat-panel detectors, indium gallium arsenide photon detectors, etc. However, these detectors are expensive to prepare, have poor biocompatibility, and have high rigidity, making them difficult to use in humans or organisms. In order to achieve high-fidelity and excellent spatial resolution imaging of complex objects, it is urgent to develop highly integrated, ultra-sensitive, and low-voltage skin-like photoelectric devices for remote, continuous, and long-term biological monitoring.

[0003] Stretchable organic optoelectronic devices have become ideal candidates for next-generation radiation detectors due to their high skin conformality, functional adjustability, and ease of large-area processing, and have therefore attracted widespread attention from industry and academia. In recent years, high-density intrinsic stretchable organic transistor arrays have been fabricated based on microlithography technology and innovative material design (Wang, S., Xu, J., Wang, W. et al., Nature 2018, 555, 83–88.; Zheng YQ, Liu YX, Zhong DL, et al., Science 2021, 373, 88–94.). However, due to the complex molecular structure and microfabrication process flow, intrinsic stretchable organic electronic devices are still difficult to balance high integration, multifunctionality, and operational stability. Although stretchable organic transistors have been used as addressing units to achieve small curved imaging prototypes (Shim, H., Sim, K., Wang, B. et al., Nat. Electron. 2023, 6, 349–359.), research related to stretchable image sensors still faces huge challenges, such as pixel size, power consumption, and operational stability, which seriously hinder the realization of scalable high-resolution X-ray imaging. Stretchable multi-pixel transistor arrays based on quantum dot-doped elastic semiconductors and microcracked gold electrodes exhibit high photoresponse and wide detection range (Song, JK., Kim, J., Yoon, J. et al. Nat. Nanotechnol. 2022, 17, 849–856.), but high-resolution and ultra-sensitive scalable optical imaging technology has not been reported. Therefore, the development of flexible optoelectronic integration technology and the innovation of stretchable organic optoelectronic devices are the key to promoting the realization and further dynamic application of scalable photodetection arrays. Summary of the invention

[0004] In view of the current challenges, the purpose of the present invention is to provide a high-density stretchable organic phototransistor array and its preparation method and application. On the one hand, the stretchable polymer semiconductor layer is a nano-confined polymer film, and at the same time acts as a photosensitive layer and a semiconductor layer, directly participating in carrier transport while inducing photons, and exhibiting ideal carrier transport characteristics; on the other hand, the present invention utilizes transferable interface method-assisted photolithography stripping technology to achieve the preparation and transfer integration of micron-scale stretchable electrodes, and further realizes the preparation of high-density intrinsic stretchable organic phototransistor arrays; ultimately, a high-density, high-sensitivity and low-voltage stretchable organic phototransistor array is realized, which can achieve high-resolution imaging.

[0005] The present invention provides a high-density stretchable organic phototransistor array, wherein the high-density stretchable organic phototransistor array is an organic phototransistor based on a polymer film under nanoconfinement;

[0006] The organic phototransistor adopts a top-gate top contact, a top-gate bottom contact, a bottom-gate top contact or a bottom-gate bottom contact structure, and includes a stretchable substrate, a stretchable insulating layer, a stretchable polymer semiconductor layer, a stretchable gate electrode and a stretchable source and drain microelectrode layer;

[0007] Wherein, the stretchable polymer semiconductor layer is a nano-confined polymer film;

[0008] The nano-confined polymer film serves as a photosensitive layer and a semiconductor layer at the same time, and directly participates in carrier transmission while inducing photons.

[0009] In the above-mentioned high-density stretchable organic phototransistor array, the nano-confined polymer film is made of a conjugated polymer and an elastomeric polymer;

[0010] The conjugated polymer is a thiophene, a diketopyrrolopyrrole (DPP), an isoindigo (IID) or a naphthalimide polymer (NDI);

[0011] The elastomeric polymer is any one of unsaturated rubber, saturated rubber and thermoplastic elastomer.

[0012] Preferably, the mass ratio of the conjugated polymer to the elastomeric polymer is 1:(0.125-8);

[0013] The conjugated polymer is selected from poly{(2,5-bis(4-decyltetradecyl)-3,6-di(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dioneco-2,2'-dithiophene)}(DPP-BT), poly{2,5-bis(2-octyldodecyl)-3,6-di(thiophen-2-yl)diketopyrrole[3,4-c]pyrrole-1,4-dione-alt-thiophene[3,2-b]thiophene}(DPPT-TT), poly(quaterthiopheneacetic acid diketopyrrole) (PTDPPTFT4), poly{2,2'-(2,5-bis(2-octyldodecyl)-3,6-isoindigo-alt-thiophene-2,5-diyl}(PIID2T) , poly(isoindigo trifluoromethylthiophene vinylthiophene) (IID-CF3TVT), poly(fluorinated isoindigo trifluoromethylthiophene vinylthiophene) (FIID-CF3TVT), poly{(4,4,9,9-tetradecyl-indacenyl[1,2-b:5,6-b']dithiophene-2,7-diyl)-alt-(benzo[c][1,2,5]thiadiazole-4,7-diyl)}(IDT-BT), poly(3-hexylthiophene) (P3HT), poly{[N,N9-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,59-(2,29-thiophene)}(N2200);

[0014] Preferably, the unsaturated rubber is natural rubber (NR), styrene-butadiene rubber (SBR) or chloroprene rubber (CR);

[0015] The saturated rubber is butyl rubber (IIR), ethylene propylene rubber (EPR) or polydimethylsiloxane (PDMS);

[0016] The thermoplastic elastomer is any one of hydrogenated styrene-butadiene block copolymer (SEBS), polyacrylate rubber (ABR), polyurethane elastomer (PU), polyolefin elastomer (TPO) and polyether ester elastomer (TPEE).

[0017] In the above-mentioned high-density stretchable organic phototransistor array, the stretchable substrate and the stretchable insulating layer are both made of elastomeric polymers;

[0018] The elastomeric polymer is any one of unsaturated rubber, saturated rubber and thermoplastic elastomer;

[0019] The unsaturated rubber is natural rubber (NR), styrene-butadiene rubber (SBR) or chloroprene rubber (CR);

[0020] The saturated rubber is butyl rubber (IIR), ethylene propylene rubber (EPR) or polydimethylsiloxane (PDMS);

[0021] The thermoplastic elastomer is any one of hydrogenated styrene-butadiene block copolymer (SEBS), polyacrylate rubber (ABR), polyurethane elastomer (PU), polyolefin elastomer (TPO) and polyether ester elastomer (TPEE).

[0022] In the above-mentioned high-density stretchable organic phototransistor array, the thickness of the stretchable substrate is 500 μm to 2 mm;

[0023] The thickness of the stretchable insulating layer is 1.0 μm to 1.5 μm;

[0024] The thickness of the stretchable polymer semiconductor layer is 50-150 nm.

[0025] In the above-mentioned high-density stretchable organic phototransistor array, the stretchable gate electrode and the stretchable source and drain microelectrodes are all made of intrinsic stretchable conductive materials;

[0026] The intrinsically stretchable conductive material is any one of metallic single-walled carbon nanotubes, metal nanowires, liquid metals, conductive polymers and two-dimensional conductive materials;

[0027] Preferably, the stretchable gate electrode is selected from any one of metallic single-walled carbon nanotubes, metal nanowires and liquid metals;

[0028] Preferably, the stretchable source and drain microelectrodes are selected from any one of metallic single-walled carbon nanotubes, metal nanowires and two-dimensional conductive materials;

[0029] The metallic single-walled carbon nanotubes may specifically be P1-SWNT, P2-SWNT, P3-SWNT, P5-SWNT, P7-SWNT, P8-SWNT or P9-SWNT;

[0030] The metal nanowires may specifically be silver nanowires (Ag NWs), gold nanowires (Au NWs) or copper nanowires (CuNWs);

[0031] The liquid metal may specifically be a gallium-indium alloy (EGaIn);

[0032] The conductive polymer is poly(3,4-ethylenedioxythiophene)-polyvinylbenzenesulfonic acid (PEDOT:PSS);

[0033] The two-dimensional conductive material is graphene (G) or the like;

[0034] The conductivity of the stretchable gate electrode and the stretchable source and drain microelectrodes is 5×10 3 ~5×10 5 S cm -1 .

[0035] The present invention further provides a method for preparing the high-density stretchable organic phototransistor array, comprising the following steps:

[0036] S1, preparing the stretchable substrate, the stretchable insulating layer, the stretchable polymer semiconductor layer and the stretchable gate electrode on a substrate respectively;

[0037] S2, spin coating a photoresist on a substrate, followed by photolithography and development to form a patterned photoresist; depositing a sacrificial layer on the patterned photoresist, preparing a stretchable electrode on the sacrificial layer, peeling off the photoresist portion, leaving the patterned microelectrode, and obtaining the stretchable source and drain microelectrodes;

[0038] S3. According to the structure of the stretchable organic phototransistor, the components constituting the stretchable organic phototransistor are transferred and bonded to obtain the high-density stretchable organic phototransistor array.

[0039] In the above-mentioned method for preparing a high-density stretchable organic phototransistor array, in steps S1 and S2, the substrate is any one of a silicon wafer, a SiO2-Si silicon substrate, quartz, glass, PET plastic, a sapphire substrate, ceramics, metal and cemented carbide;

[0040] In step S1, the stretchable polymer semiconductor layer is prepared by spin coating a polymer solution and then annealing;

[0041] The solvent for preparing the polymer solution of the stretched polymer semiconductor layer is at least one of chlorobenzene, dichlorobenzene, chloroform and xylene;

[0042] The total mass concentration of the polymer solution for preparing the stretched polymer semiconductor layer is 5 mg / ml to 30 mg / ml;

[0043] The spin coating speed for preparing the stretched polymer semiconductor layer is 1000-4000 r / min, and the spin coating time is 40 s-1 min;

[0044] The annealing temperature for preparing the stretched polymer semiconductor layer is 100 to 250° C.;

[0045] In step S2, the sacrificial layer is a small molecule film, a hydrolyzable or degradable polymer film;

[0046] The thickness of the sacrificial layer is 30 to 300 nm;

[0047] The small molecules in the small molecule film are selected from metal halides, such as lithium fluoride (LiF), lithium chloride (LiCl), silver fluoride (AgF), etc.

[0048] The polymer in the hydrolyzable or degradable polymer film is selected from any one of dextran (Glu), polyvinyl alcohol (PVA), polyacrylamide (PAM) and polycarbonate (PC);

[0049] The small molecule film is prepared by vacuum evaporation at a rate of

[0050] The hydrolyzable or degradable polymer film is prepared by spin coating a polymer solution and then annealing;

[0051] The solvent for preparing the hydrolyzable or degradable polymer solution is any one of deionized water, tetrahydrofuran and chloroform;

[0052] The concentration of the hydrolyzable or degradable polymer solution is prepared to be 10 mg / ml to 100 mg / ml;

[0053] The spin coating speed for preparing the hydrolyzable or degradable polymer solution is 3000-6000 r / min, and the spin coating time is 40 s-1 min;

[0054] The annealing temperature for preparing the hydrolyzable or degradable polymer solution is 40 to 200° C.;

[0055] The stretchable source and drain microelectrodes are transferred by mechanical stripping, thermal stripping or hydrolysis release.

[0056] The present invention also protects the use of the high-density stretchable organic phototransistor array described in any of the above items in the preparation of wearable photodetectors or imaging.

[0057] In the above application, the wearable photodetector or the imaging detectable light has a wavelength band of X-rays, ultraviolet light, visible light or near-infrared light.

[0058] The present invention has the following beneficial effects:

[0059] (1) The present invention uses a nano-confined polymer film to stretch the polymer semiconductor layer, which also serves as a photosensitive layer and a semiconductor layer, and directly participates in carrier transport while inducing photons. Experiments have shown that the high-density stretchable organic phototransistor array of the present invention exhibits excellent uniformity, stable operation at low voltage and ideal carrier transport characteristics, and exhibits uniform, sensitive and stable X-ray detection capabilities, and can achieve excellent photoelectric detection performance even under a tensile strain of up to 100%.

[0060] (2) The present invention proposes a transferable interface method-assisted photolithography stripping technology, specifically, depositing a sacrificial layer on the patterned photoresist, preparing a stretchable electrode on the sacrificial layer, stripping the photoresist part, leaving the patterned microelectrode, the sacrificial layer mainly functions as follows: first, covering the unclean substrate surface caused by photolithography to ensure the integrity of the electrode during the stripping process; second, providing a higher surface energy to increase the adhesion between the stretchable electrode and the transfer layer, thereby assisting the transfer and facilitating the integration of a non-destructive, complete and repeatable stretchable microelectrode array, and finally obtaining a high-density, micron-scale and easily integrated stretchable electrode array. Based on this microelectrode, the prepared high-density stretchable organic phototransistor array not only exhibits ideal carrier transport characteristics, but also can achieve low-voltage, high-sensitivity and low-dose light detection.

[0061] (3) The present invention has the unique advantages of low cost, large area and high flexibility, and can be directly attached to the surface or interior of complex objects, thereby obtaining high-definition detection results at a low radiation dose and in a very short time. The present invention has high yield, device uniformity and operational stability, greatly promoting the development of stretchable flat-panel detectors and scalable imaging technology, and is of great significance for realizing multiplexing and image sensing systems with stronger computing power. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A schematic diagram of the device structure used in the high-density stretchable organic phototransistor array provided by the present invention, including a schematic diagram of the structure of a top gate top contact, a top gate bottom contact, a bottom gate top contact and a bottom gate bottom contact structure.

[0063] Figure 2 The present invention provides a main preparation process for a high-density stretchable organic phototransistor array based on a transferable interface method.

[0064] Figure 3 (a) is a microscope image of a microelectrode prepared by transferable interface method assisted photolithography stripping in an embodiment of the present invention; (b) is a microscope image of a high-density stretchable organic phototransistor array prepared in an embodiment of the present invention; (c) is a photograph of the prepared patterned stretchable microelectrode.

[0065] Figure 4 (a) is the transmission characteristic curve of the high-density stretchable organic phototransistor array prepared in accordance with an embodiment of the present invention; (b) is the device mobility statistics of the array prepared in accordance with an embodiment of the present invention.

[0066] Figure 5 (a) is the photoresponse curve of the high-density stretchable organic phototransistor array prepared in an embodiment of the present invention under different doses of X-rays; (b) is the photoresponse statistics of the array prepared in an embodiment of the present invention.

[0067] Figure 6 The photoresponse curves of the high-density stretchable organic phototransistor array prepared in an embodiment of the present invention under different stress stretching conditions.

[0068] Figure 7 (a) Theoretical low-dose imaging and (b) actual single-device X-ray imaging of a high-density stretchable organic phototransistor array prepared according to an embodiment of the present invention. DETAILED DESCRIPTION

[0069] As described in the background art, current stretchable organic transistors still face the dilemma of being unable to achieve scalable high-resolution X-ray imaging. Based on this, in the first aspect, the present invention provides a high-density stretchable organic phototransistor array, wherein the high-density stretchable organic phototransistor array is an organic phototransistor based on a polymer film under nanoconfinement; the organic phototransistor adopts a top-gate top contact, a top-gate bottom contact, a bottom-gate top contact or a bottom-gate bottom contact structure, including a stretchable substrate, a stretchable insulating layer, a stretchable polymer semiconductor layer, a stretchable gate electrode and a stretchable source and drain microelectrode layer, such as Figure 1As shown, taking the bottom gate top contact bottom gate top contact structure as an example, the organic phototransistor organic phototransistor includes a stretchable substrate, a stretchable insulating gate, a stretchable insulating layer, a stretchable polymer semiconductor layer and a stretchable source and drain microelectrode layer from bottom to top; wherein the stretchable polymer semiconductor layer is a nano-confined polymer film, and the nano-confined polymer film serves as a photosensitive layer and a semiconductor layer at the same time, directly participating in carrier transport while inducing photons. In the present invention, with a nano-confined polymer film stretchable polymer semiconductor layer, the high-density stretchable organic phototransistor array has excellent uniformity, can work stably at low voltage and has ideal carrier transport characteristics.

[0070] According to the present invention, the nanoconfined polymer film is made of a conjugated polymer and an elastomeric polymer, and the conjugated polymer can be a thiophene, a diketopyrrolopyrrole (DPP), an isoindigo (IID) or a naphthaleneimide polymer (NDI), such as poly{(2,5-bis(4-decyltetradecyl)-3,6-di(thiophene-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dioneco-2,2'-dithiophene)}(DPP-BT), poly{2,5-bis(2-octyldodecyl)-3,6-di(thiophene-2-yl)dionepyrrolo[3,4-c]pyrrole-1,4-dione-alt-thiophene[3,2-b]thiophene}(DPPT-TT), poly(tetrathiophene)-1,4-dione phenacetic acid diketopyrrole) (PTDPPTFT4), poly {2,2'-(2,5-bis(2-octyldodecyl)-3,6-isoindigo-alt-thiophene-2,5-diyl} (PIID2T), poly (isoindigo trifluoromethylthiophene vinylthiophene) (IID-CF3TVT), poly (fluorinated isoindigo trifluoromethylthiophene vinylthiophene) (FIID-CF3TVT), poly {(4,4,9,9-tetradecanoyl-indacenyl[1,2-b:5,6-b']dithiophene-2,7-diyl)-alt-(benzo[c][1,2,5]thiadiazole-4,7-diyl)} (IDT-BT), poly (3-hexylthiophene) (P3HT), poly {[N, Any one of N9-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,59-(2,29-thiophene)}(N2200); wherein, the synthesis routes of polymers IID-CF3TVT and FIID-CF3TVT can refer to the patent (Chinese Patent 202010098740.9). The elastomeric polymer can be any one of unsaturated rubber, saturated rubber and thermoplastic elastomer, unsaturated rubber such as natural rubber (NR), styrene-butadiene rubber (SBR) or chloroprene rubber (CR), saturated rubber such as butyl rubber (IIR), ethylene-propylene rubber (EPR) or polydimethylsiloxane (PDMS), thermoplastic elastomer Any one of hydrogenated styrene-butadiene block copolymer (SEBS), polyacrylate rubber (ABR), polyurethane elastomer (PU), polyolefin elastomer (TPO) and polyether ester elastomer (TPEE). Preferably, the mass ratio of the conjugated polymer to the elastomeric polymer is 1:(0.125-8), such as 1:2.3. For example, the nanoconfined polymer film is made of poly{(2,5-bis(4-decyltetradecyl)-3,6-di(thiophene-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione co-2,2'-dithiophene)} (DPP-BT) and hydrogenated styrene-butadiene block copolymer (SEBS) in a mass ratio of 1:2.3.

[0071] According to the present invention, the stretchable substrate and the stretchable insulating layer are both made of an elastomeric polymer, and the elastomeric polymer is any one of an unsaturated rubber, a saturated rubber and a thermoplastic elastomer; an unsaturated rubber such as natural rubber (NR), styrene-butadiene rubber (SBR) or chloroprene rubber (CR), a saturated rubber such as butyl rubber (IIR), ethylene-propylene rubber (EPR) or polydimethylsiloxane (PDMS), a thermoplastic elastomer such as hydrogenated styrene-butadiene block copolymer (SEBS), polyacrylate rubber (ABR), polyurethane elastomer (PU), polyolefin elastomer (TPO) and polyether ester elastomer (TPEE).

[0072] According to the present invention, the ranges of the stretchable substrate, the stretchable insulating layer and the stretchable polymer semiconductor layer can be adjusted within a reasonable range. Preferably, the thickness of the stretchable substrate is 500μm~2mm, preferably 300μm~1.2mm, such as 1.2mm; the thickness of the stretchable insulating layer is 1.0μm~1.5μm, preferably 1.1μm~1.3μm, such as 1.2μm; the thickness of the stretchable polymer semiconductor layer is 50~150nm, preferably 70~120nm, such as 100nm.

[0073] According to the present invention, the stretchable gate electrode and the stretchable source and drain microelectrodes are all made of intrinsic stretchable conductive materials, such as any one of metallic single-walled carbon nanotubes, metal nanowires, liquid metals, conductive polymers and two-dimensional conductive materials; preferably, the stretchable gate electrode is selected from any one of metallic single-walled carbon nanotubes, metal nanowires and liquid metals; preferably, the stretchable source and drain microelectrodes are selected from any one of metallic single-walled carbon nanotubes, metal nanowires and two-dimensional conductive materials; the metallic single-walled carbon nanotubes can specifically be P1-SWNT, P2-SWNT, P3-SWNT, P5-SWNT, P7-SWNT, P8-SWNT or P9-SWNT; the metal nanowires can specifically be silver nanowires (Ag NWs), gold nanowires (Au NWs) or copper nanowires (Cu NWs); the liquid metal can be specifically gallium-indium alloy (EGaIn); the conductive polymer is poly(3,4-ethylenedioxythiophene)-polyvinylbenzenesulfonic acid (PEDOT:PSS); the two-dimensional conductive material is graphene (G), etc.; the conductivity of the stretchable gate electrode and the stretchable source and drain microelectrodes is 5×10 3 ~5×10 5 S cm -1 , such as 1×10 4 S cm -1 .

[0074] According to the present invention, the organic phototransistors in the high-density stretchable organic phototransistor array of the present invention are arranged periodically, and their density can be adjusted within a reasonable range. In a specific embodiment of the present invention, the density of the organic phototransistors is 41,000 transistors / cm 2 .

[0075] In a second aspect, the present invention provides a method for preparing a high-density stretchable organic phototransistor array as described in any one of the above items, comprising the following steps: S1, preparing the stretchable substrate, the stretchable insulating layer, the stretchable polymer semiconductor layer and the stretchable gate electrode on a substrate respectively; S2, Figure 2 As shown, a photoresist is spin-coated on a substrate, followed by photolithography and development to form a patterned photoresist; a sacrificial layer is deposited on the patterned photoresist, and a stretchable electrode is prepared on the sacrificial layer, and the photoresist portion is peeled off, leaving the patterned microelectrode to obtain the stretchable source and drain microelectrodes; S3, according to the structure of the stretchable organic phototransistor, the components constituting the stretchable organic phototransistor are transferred and bonded to obtain the high-density stretchable organic phototransistor array. The present invention adopts the technology of transferable interface method assisted photolithography peeling to prepare micron-scale, highly uniform, stable and easy-to-integrate high-density stretchable microelectrodes. Based on this stretchable microelectrode, the prepared stretchable organic phototransistor array not only exhibits ideal carrier transport characteristics, but also realizes high-sensitivity, low-voltage and low-dose stretchable X-ray detection.

[0076] According to the present invention, in steps S1 and S2, the substrate is any one of a silicon wafer, a SiO2-Si silicon substrate, quartz, glass, PET plastic, a sapphire substrate, ceramics, metal and cemented carbide.

[0077] According to the present invention, in step S1, the preparation step includes: self-assembling and growing an organic siloxane polymer on the surface of the substrate; the substrate is first treated as follows before the self-assembly and growth of the organic siloxane polymer: ultrasonically cleaning with deionized water, acetone, and isopropanol for 6-7 minutes, drying with nitrogen, and then ozonating (UVO or O3 plasma) the substrate to obtain a substrate with surface hydroxylation treatment. The self-assembled growth organic siloxane polymer is specifically prepared by heating the substrate and the organic siloxane polymer under vacuum conditions (gas phase modification) or immersing them in a solution (liquid phase modification). The organic siloxane polymer is any one of polydimethylsiloxane, octadecyltrimethoxysilane, octadecyltrichlorosilane, octadecyltrichlorosilane and phenyltrichlorosilane. For example, the gas phase modification conditions of octadecyltrichlorosilane (OTS) are as follows: a small amount of OTS is coated on the substrate after oxygen plasma cleaning, and then it is placed in a vacuum oven with a vacuum degree of 0.01 Pa, and then it is heated to 120°C and maintained for 3 hours, and then naturally cooled to room temperature to complete the modification process.

[0078] According to the present invention, in step S1, the stretchable substrate and the stretchable insulating layer are both prepared on a substrate of a surface self-assembled growth organic siloxane polymer by any one of drop coating, spin coating, scraping, rod coating, Czochralski method and "roll-to-roll" process. The solvent used is any one of benzene, toluene, xylene, ethyl acetate, chloroform, dichloromethane, n-hexane, heptane, or cyclohexane. For example, a silicon wafer of surface self-assembled organic siloxane is placed on a hot table at 20°C, and a SEBS-H1221 toluene solution with a concentration of 200 mg / mL is evenly drop coated on the silicon wafer of the surface self-assembled organic siloxane, and then kept at 50°C for 4 hours, and then kept at 90°C for 1 hour to obtain a stretchable substrate with a thickness of 1.2 mm. For example, a silicon wafer with self-assembled organic siloxane on its surface is placed at the center of the rotor of a coater, 200 mL of a 65 mg / mL SEBS-H1052 cyclohexane solution is extracted with a pipette, and then evenly dropped on the silicon wafer with the self-assembled molecular layer, the coater is started, and maintained at a speed of 3000 rpm for 1 minute. Finally, the silicon wafer is removed and annealed on a hot plate at 80°C for 1 hour to obtain a stretchable insulating layer with a thickness of 1.2 μm.

[0079] According to the present invention, in step S1, the stretchable polymer semiconductor layer is prepared by spin coating a mixed solution of a conjugated polymer and an elastomeric polymer on a substrate of a surface self-assembled growth organic siloxane polymer, and annealing. The solvent for preparing the polymer solution of the stretchable polymer semiconductor layer is at least one of chlorobenzene, dichlorobenzene, chloroform and xylene; the total mass concentration of the polymer solution for preparing the stretchable polymer semiconductor layer is 5mg / ml to 30mg / ml, such as 10mg / ml. The spin coating speed for preparing the stretchable polymer semiconductor layer is 1000 to 4000r / min, such as 2000r / min, and the spin coating time is 40s to 1min, such as 1 minute; the annealing temperature for preparing the stretchable polymer semiconductor layer is 100 to 250°C, such as 150°C; effective control of nano-confinement can be achieved by changing any one of the blending ratio, spin coating speed, annealing temperature, and spin coating method. For example, the silicon wafer with the self-assembled molecular layer on the surface in step (2) is placed at the center of a spin coater, 20 μL of a DPP-BT / SEBS chlorobenzene solution with a mass ratio of 3:7 and a concentration of 10 mg / ml of the two polymers is dripped onto the silicon wafer with the self-assembled molecular layer, and then spin-coated at a speed of 2000 rpm for 1 minute. Finally, the silicon wafer is placed on a hot plate and annealed at 150° C. for 15 minutes to obtain a stretchable polymer semiconductor layer with a thickness of 100 nm.

[0080] According to the present invention, in step S1, the stretchable gate electrode can be prepared by spraying or inkjet printing; when the stretchable gate electrode and the stretchable source and drain microelectrodes are made of carbon nanotubes, the carbon nanotube electrodes are all prepared by spraying or inkjet printing on a substrate of a surface self-assembled organic siloxane polymer; the solvent used in the carbon nanotube solution is any one of water, ethanol, isopropanol, chlorobenzene, N-methylpyrrolidone or a mixed solvent thereof; the concentration of the carbon nanotube solution is 0.1-0.5 mg / ml; the spraying strip The conditions are: the substrate temperature is 60-120°C, the distance between the spray gun and the substrate is 7-15 cm, the spraying speed is 0.1-3 mL / min, and the volume of the spraying solution is 1-5 mL; for example, a silicon wafer self-assembled with organic siloxane is placed on a hot stage at 80°C for 5 minutes, a 0.3 mg / mL carbon nanotube P3-SWNT isopropanol solution is transferred to the volume chamber of the spray gun, and then evenly sprayed on the silicon wafer of the self-assembled organic siloxane at a rate of 0.5 mL / min, wherein the distance between the spray gun nozzle and the silicon wafer is 10 cm.

[0081] According to the present invention, in step S2, the substrate is first treated as follows before spin coating the photoresist: ultrasonic cleaning with deionized water, acetone, and isopropanol for 6-7 minutes in sequence, and drying with nitrogen. The photoresist can be a negative photoresist, a positive photoresist suitable for lift-off, and an electron beam photoresist; specifically, the negative photoresist can be any one of a polyester glue system: polyvinyl cinnamate (KPR) glue and polyethylene oxyethyl cinnamate (OSR) glue and a cyclized rubber system: polyhydrocarbon-bisazide (OMR) glue; the positive photoresist can be any one of an o-diazonaphthoquinone-linear phenolic resin system: AZ5214, AZnLOF2000, and AZnLOF5000 photoresist; the electron beam photoresist can be a poly(methyl)acrylate (PMMA) and its derivative system: AR-N 4340, AR-P617PMMA / MA, AR-N 7520, AR-N 7500, RN 218, RN246, MA-N 400, and MA-N1400 photoresist, and an epoxy resin system: SU8 Any one of SU8 2005 and SU8 2015 photoresists. According to the present invention, in step S2, the thickness of the photoresist is 0.8-3 μm, preferably 1.2-2 μm, and the part with the photoresist is stripped by acetone ultrasonic cleaning.

[0082] According to the present invention, in step S2, the sacrificial layer is a small molecule film, a hydrolyzable or degradable polymer film; the thickness of the sacrificial layer is 30 to 300 nm, preferably 50 to 150 nm, such as 100 nm; the small molecules in the small molecule film are selected from metal halides, such as lithium fluoride (LiF), lithium chloride (LiCl), silver fluoride (AgF), etc.; the polymer in the hydrolyzable or degradable polymer film is selected from any one of dextran (Glu), polyvinyl alcohol (PVA), polyacrylamide (PAM) and polycarbonate (PC); preferably, the small molecule film is prepared by vacuum evaporation, and the evaporation rate is like The growth quality and thickness of the film can be effectively controlled by adjusting the evaporation rate and the evaporation time; the hydrolyzable or degradable polymer film is prepared by spin coating a polymer solution and then annealing; preferably, the solvent for preparing the hydrolyzable or degradable polymer solution can be any one of deionized water, tetrahydrofuran and chloroform; the concentration of the hydrolyzable or degradable polymer solution can be 10 mg / ml to 100 mg / ml; the spin coating speed for preparing the hydrolyzable or degradable polymer solution can be 3000 to 6000 r / min, and the spin coating time can be 40s to 1min; the annealing temperature for preparing the hydrolyzable or degradable polymer solution can be 40 to 200°C, and the quality and thickness of the film can be regulated and optimized by changing the solution concentration, the spin coating speed and the annealing temperature. The stretchable source and drain microelectrodes are transferred by mechanical stripping, thermal stripping or hydrolysis release, wherein the transfer method of the stretchable source and drain microelectrodes can be determined according to the degradation method of the sacrificial layer. For example, when a small molecule film is used, the stretchable source and drain microelectrodes only need to be transferred by mechanical stripping; when a small molecule film and a pyrolyzable polymer film are selected, the sacrificial layer and the microelectrode can be transferred together by thermal stripping or the sacrificial layer can be thermally degraded; when a hydrolyzable polymer film is selected, when the hydrolysis release method is used for transfer, only the microelectrode is transferred, and the sacrificial layer disappears by hydrolysis; no matter which method is used, the microelectrode can be transferred and integrated into the intrinsic stretchable device. In the present invention, the main functions of the sacrificial layer include: first, covering the unclean substrate surface caused by photolithography to ensure the integrity of the electrode during the stripping process; second, providing a higher surface energy to increase the adhesion of the stretchable electrode to the transfer layer, thereby assisting the transfer and facilitating the realization of lossless, complete and repeatable stretchable microelectrode array integration, and finally obtaining a high-density, micron-scale and easy-to-integrate stretchable electrode array. The present invention proposes a transferable interface strategy to prepare stretchable microelectrodes with high resolution, achieving the simultaneous improvement of micrometer-scale patterning, yield and universality of stretchable electrodes. Based on this stretchable microelectrode, the prepared high-density stretchable organic phototransistor array not only exhibits high sensitivity, low voltage and low dose X-ray detection capabilities, but also has high stretchability, device uniformity and operational stability.

[0083] According to the present invention, in step S2, the stretchable source and drain microelectrodes can be prepared by spraying or inkjet printing; the conductivity of the stretchable microelectrode can be effectively controlled by changing any one of the spraying speed, spraying amount, and spraying distance. The conductivity of the stretchable microelectrode is 5×10 3 S cm -1 ~5×10 5 S cm -1 , preferably 8×10 5 ~3×10 4 S cm -1For example, a silicon wafer with a evaporated sacrificial layer is placed on a hot stage at 120°C for 15 minutes, and then 2 mL of an isopropanol solution of carbon nanotubes P3-SWNT with a concentration of 0.3 mg / mL is extracted with a 5 mL pipette, and then evenly sprayed on the silicon wafer with a self-assembled molecular layer at a rate of 0.5 mL / min, wherein the distance between the spray gun nozzle and the silicon wafer is 12 cm, and then the part with the photoresist is peeled off with acetone ultrasonic cleaning, and a patterned silicon wafer with stretchable source and drain microelectrodes can be prepared.

[0084] According to the present invention, in step S3, taking the bottom gate top contact structure as an example, the stretchable substrate is first transferred from the substrate with the self-assembled molecular layer, and then the stretchable substrate is covered on the stretchable gate electrode by gently laminating from one side to the other side; then the stretchable gate electrode is transferred to the stretchable substrate by thermal lamination or room temperature lamination, and the bubbles generated at the interface during the lamination process are removed by vacuuming; then the same method is adopted to transfer the stretchable insulating layer and the stretchable polymer semiconductor layer to the stretchable substrate respectively; finally, the stretchable source and drain microelectrodes are transferred to the stretchable substrate by mechanical stripping, thermal stripping or hydrolysis release. Preferably, the thermal lamination process is carried out in a vacuum drying oven; the conditions of the thermal lamination are: the vacuum degree is 0.1 to 5 Pascals, the temperature during the heating treatment is 40 to 90°C, and the heating treatment time is 0.5 to 1 hour; for example, it is kept at 60°C for 30 minutes in a vacuum drying oven with a vacuum degree of 0.1 Pascal.

[0085] In a third aspect, the present invention provides an application of the high-density stretchable organic phototransistor array in the preparation of wearable photodetectors or imaging. The detectable light band is X-rays, ultraviolet light, visible light or near-infrared light, and the detectable light band can be adjusted by replacing semiconductor materials that absorb the corresponding band.

[0086] The present invention is further described in detail below in conjunction with specific embodiments, and the examples provided are only for illustrating the present invention, rather than for limiting the scope of the present invention. The examples provided below can be used as a guide for further improvements by those of ordinary skill in the art, and do not constitute a limitation of the present invention in any way.

[0087] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the materials, reagents, etc. used, unless otherwise specified, can be obtained from commercial channels.

[0088] Example 1

[0089] In this embodiment, based on the nano-confined DPP-BT / SEBS polymer blend film, a high-density stretchable organic phototransistor array with a bottom-gate top-contact structure is prepared according to the following steps:

[0090] S1. Prepare a stretchable substrate, a stretchable insulating layer, a stretchable polymer semiconductor layer and a stretchable gate electrode on a substrate respectively. The specific steps are as follows:

[0091] 1) The silicon wafer is ultrasonically cleaned with deionized water, acetone, and isopropanol for 6-7 minutes in sequence, the solvent on the substrate is removed by purging with high-purity nitrogen, and then the substrate is subjected to ozonation (UVO) treatment to obtain a substrate with surface hydroxylation treatment;

[0092] 2) Prepare an organosiloxane polymer modification layer on the substrate of step (1) by using a gas phase modification method or a liquid phase modification method. The gas phase modification conditions of octadecyltrichlorosilane (OTS) are as follows: a small amount of OTS is applied to the substrate after oxygen plasma cleaning, and then the substrate is placed in a vacuum oven with a vacuum degree of 0.01 Pa, and then heated to 120°C and maintained for 3 hours, and then naturally cooled to room temperature to complete the modification process;

[0093] 3) placing the silicon wafer with the self-assembled organosiloxane on the surface in step (2) on a hot stage at 20°C, slowly extracting 1 ml of SEBS-H1221 toluene solution (concentration of 200 mg / mL) with a 1 mL syringe and evenly dropping it on the silicon wafer with the self-assembled molecular layer, and then keeping it at 50°C for 4 hours and then at 90°C for 1 hour to obtain a stretchable substrate with a thickness of 1.2 mm;

[0094] 4) The silicon wafer with the self-assembled organosiloxane on the surface in step (2) was placed on a hot stage at 80°C for 5 minutes, 2 mL of carbon nanotube P3-SWNT isopropanol solution (0.3 mg / mL) was transferred to the volume chamber of the spray gun, and then evenly sprayed on the silicon wafer with the self-assembled molecular layer at a rate of 0.5 mL / min (wherein the distance between the spray gun nozzle and the silicon wafer was 10 cm), and a stretchable gate electrode (conductivity of 1×10 4 S cm -1 ).

[0095] 5) Place the silicon wafer with the self-assembled organosiloxane on the surface in step (2) at the center of the rotor of the coating machine, use a 1 mL pipette to extract 200 mL of SEBS-H1052 cyclohexane solution (concentration of 65 mg / mL), and then evenly drop it on the silicon wafer with the self-assembled molecular layer, start the coating machine, and keep it at a speed of 3000 rpm for 1 minute. Finally, remove the silicon wafer and place it on a hot plate at 80°C for annealing for 1 hour to obtain a stretchable insulating layer with a thickness of 1.2 μm.

[0096] 6) Place the silicon wafer with the surface self-assembled molecular layer in step (2) at the center of the coating machine, drop 20 μL of DPP-BT / SEBS chlorobenzene solution (wherein the mass ratio of the two polymers is 3:7 and the concentration is 10 mg / ml) on the silicon wafer, and then spin coat at 2000 rpm for 1 minute. Finally, place the silicon wafer on a hot plate and anneal at 150° C. for 15 minutes to obtain a stretchable polymer semiconductor layer with a thickness of 100 nm.

[0097] S2, such as Figure 2 As shown, a photoresist is spin-coated on a substrate, followed by photolithography and development to form a patterned photoresist; a sacrificial layer is deposited on the patterned photoresist, and a stretchable electrode is prepared on the sacrificial layer, and the photoresist portion is peeled off to leave the patterned microelectrode, thereby obtaining a stretchable source and drain microelectrode. The specific steps are as follows:

[0098] 7) The silicon wafer was ultrasonically cleaned with deionized water, acetone, and isopropanol for 6-7 minutes and dried with nitrogen. AZ5214 photoresist was spin-coated on the cleaned silicon wafer at a speed of 3000 rpm and annealed for 3 minutes, then placed under a photomask for UV exposure, and then developed and cleaned in sequence. The thickness of the resulting photoresist was 1.5 μm.

[0099] 8) Evaporating a small molecule lithium fluoride sacrificial layer on the patterned photoresist silicon wafer to A sacrificial layer with a thickness of 100 nm was deposited at a deposition rate of .

[0100] 9) The silicon wafer with the evaporated sacrificial layer was placed on a hot plate at 120°C for 15 minutes, and then 2 mL of isopropanol solution of carbon nanotubes P3-SWNT (concentration of 0.3 mg / mL) was extracted with a 5 mL pipette, and then evenly sprayed on the silicon wafer with the self-assembled molecular layer at a rate of 0.5 mL / min (where the distance between the spray gun nozzle and the silicon wafer was 12 cm), and then the part with the photoresist was removed by ultrasonic cleaning with acetone, and a patterned silicon wafer with stretchable source and drain microelectrodes (conductivity of 1×10 4 S cm -1 );

[0101] S3. According to the structure of the stretchable organic phototransistor, the components constituting the stretchable organic phototransistor are transferred and bonded to obtain the stretchable organic phototransistor; the stretchable organic phototransistor is processed into an array to obtain a high-density stretchable organic phototransistor array. The specific steps are as follows:

[0102] 10) The above-mentioned stretchable substrate is transferred from the substrate with the self-assembled molecular layer, and then the stretchable substrate is covered on the stretchable gate electrode by gently bonding from one side to the other. Then the stretchable gate electrode is transferred to the stretchable substrate by thermal bonding, and it is placed in a vacuum drying oven with a vacuum degree of 0.1 Pascal at 60°C for 30 minutes to eliminate bubbles generated at the interface during the bonding process, and then taken out after the temperature drops to room temperature. Subsequently, the same method is adopted to transfer the stretchable insulating layer and the stretchable polymer semiconductor layer to the stretchable substrate bonded with the gate electrode in turn; finally, the stretchable source and drain microelectrodes are transferred to the stretchable substrate bonded with the stretchable gate, the stretchable insulating layer and the stretchable semiconductor layer by mechanical stripping, thermal stripping or hydrolysis release. If the stretchable source and drain microelectrodes are directly mechanically stripped and transferred, a bottom gate top contact structure (such as Figure 1 High-density stretchable organic phototransistor array based on polymer semiconductor film).

[0103] Figure 3 (a) is a microscope image of a microelectrode prepared by transferable interface method assisted photolithography stripping in Example 1 of the present invention; (b) is a microscope image of a high-density stretchable organic phototransistor array prepared in Example 1 of the present invention; (c) is a photo of a patterned stretchable microelectrode prepared in Example 1. Figure 3 (ac) Analysis shows that Example 1 successfully prepared a lossless, high-resolution and easily integrated high-density intrinsic stretchable microelectrode array.

[0104] Figure 4 (a) is the transmission characteristic curve of the high-density stretchable organic phototransistor array prepared in Example 1 of the present invention; (b) is the device mobility statistics of the array prepared in Example 1 of the present invention. Figure 4 From the analysis of (a) and (b), it can be seen that the high-density stretchable organic phototransistor array prepared in Example 1 exhibits excellent uniformity, stable operation at low voltage and ideal carrier transport characteristics.

[0105] Figure 5 (a) is the light response curve of the high-density stretchable organic phototransistor array prepared in Example 1 of the present invention under different doses of X-ray (24.34~110.2nGy air s -1 ); (b) is the light response statistics of the array prepared in Example 1 of the present invention. Figure 6 The light response curves of the high-density stretchable organic phototransistor array prepared in Example 1 of the present invention under different stress stretching conditions are shown in FIG. Figure 5 and Figure 6Analysis shows that the high-density stretchable organic phototransistor array prepared based on this nano-confined film exhibits uniform, sensitive and stable X-ray detection capabilities. Excellent photodetection performance can be achieved even under up to 100% tensile strain. Therefore, the high-density stretchable organic phototransistor array prepared in the embodiment can fully meet the requirements of practical wearable applications.

[0106] Figure 7 (a) Theoretical low-dose imaging (24.34 nGy) of a high-density stretchable organic phototransistor array prepared in Example 1 of the present invention air s -1 ) and (b) physical single device X-ray imaging. Figure 7 Analysis of the presented images shows that the high-density stretchable organic phototransistor array prepared in Example 1 can achieve high-resolution X-ray imaging of complex objects.

[0107] Example 2

[0108] In this embodiment, based on the nano-confined DPPT-TT / SEBS polymer blend film, a high-density stretchable organic phototransistor array with a bottom-gate bottom-contact structure is prepared according to the following steps.

[0109] The same preparation method as in Example 1 was followed, except that the polymer DPP-BT / SEBS chlorobenzene solution was replaced with DPPT-TT / SEBS chlorobenzene solution, and the remaining steps were the same.

[0110] The high-density stretchable organic phototransistor array prepared in this embodiment also exhibits uniform, sensitive and stable X-ray detection capabilities, which can fully meet the requirements of practical wearable applications.

[0111] Example 3

[0112] In this embodiment, based on the nano-confined FIID-CF3TVT / SEBS polymer blend film, a high-density stretchable organic phototransistor array with a bottom-gate top-contact structure is prepared according to the following steps.

[0113] The same preparation method as in Example 1 was used, except that the polymer DPP-BT / SEBS chlorobenzene solution was replaced with FIID-CF3TVT / SEBS xylene solution, and the annealing temperature was changed from 150° C. to 220° C., and the remaining steps were the same.

[0114] The high-density stretchable organic phototransistor array prepared in this embodiment also exhibits uniform, sensitive and stable X-ray detection capabilities, which can fully meet the requirements of practical wearable applications.

[0115] Example 4

[0116] In this embodiment, based on the nano-confined N2200 / SEBS polymer blend film, a high-density stretchable organic phototransistor array with a bottom-gate top-contact structure is prepared according to the following steps.

[0117] The same preparation method as in Example 1 was used, except that the polymer DPP-BT / SEBS chlorobenzene solution was replaced by N2200 / SEBS chlorobenzene solution, and the annealing temperature was changed from 150° C. to 180° C., and the remaining steps were the same.

[0118] The high-density stretchable organic phototransistor array prepared in this embodiment also exhibits uniform, sensitive and stable X-ray detection capabilities, which can fully meet the requirements of practical wearable applications.

[0119] Comparative Example 1

[0120] In this embodiment, a DPP-BT / SEBS polymer blend film is prepared based on conventional photolithography technology, and a stretchable organic phototransistor array with a bottom-gate top-contact structure is attempted to be prepared according to the following steps.

[0121] The same preparation method as in Example 1 is used, except for removing the step of the evaporated sacrificial layer, and the remaining steps are the same.

[0122] In this comparative example, a high-density stretchable organic phototransistor array cannot be prepared. Due to the lack of a sacrificial layer, it is impossible to achieve lossless, complete and repeatable preparation and transfer of stretchable source and drain microelectrodes.

[0123] Comparative Example 2

[0124] In this embodiment, based on the FIID-CF3TVT / SEBS polymer film prepared by conventional photolithography technology, a stretchable organic phototransistor array with a bottom-gate top-contact structure is attempted to be prepared according to the following steps.

[0125] The same preparation method as in Example 3 was followed, except for removing the step of the evaporated sacrificial layer, and the remaining steps were the same.

[0126] Similarly, a high-density stretchable organic phototransistor array cannot be prepared in this comparative example, because the lack of a sacrificial layer makes it impossible to achieve lossless, complete and repeatable preparation and transfer of stretchable source and drain microelectrodes.

[0127] The present invention has been described in detail above. For those skilled in the art, without departing from the purpose and scope of the present invention, can implement the present invention in a wider range under equivalent parameters, concentrations and conditions. Although the present invention provides specific embodiments, it should be understood that the present invention can be further improved. In a word, according to the principle of the present invention, the application is intended to include any changes, uses or improvements to the present invention, including departing from the disclosed scope in the application and the changes made with conventional techniques known in the art.

Claims

1. A high-density stretchable organic phototransistor array, characterized in that: The high-density stretchable organic phototransistor array is an organic phototransistor based on a polymer film under nanoconfinement; The organic phototransistor adopts a top-gate top contact, a top-gate bottom contact, a bottom-gate top contact or a bottom-gate bottom contact structure, and includes a stretchable substrate, a stretchable insulating layer, a stretchable polymer semiconductor layer, a stretchable gate electrode and a stretchable source and drain microelectrode layer; Wherein, the stretchable polymer semiconductor layer is a nano-confined polymer film; The nano-confined polymer film serves as a photosensitive layer and a semiconductor layer at the same time, and directly participates in carrier transmission while inducing photons.

2. The high-density stretchable organic phototransistor array according to claim 1, characterized in that: The nano-confined polymer film is made of a conjugated polymer and an elastomeric polymer; The conjugated polymer is a thiophene, diketopyrrolopyrrole, isoindigo or naphthalimide polymer; The elastomeric polymer is any one of unsaturated rubber, saturated rubber and thermoplastic elastomer.

3. The high-density stretchable organic phototransistor array according to claim 2, characterized in that: The mass ratio of the conjugated polymer to the elastomeric polymer is 1:(0.125-8); The conjugated polymer is selected from poly{(2,5-bis(4-decyltetradecyl)-3,6-di(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dioneco-2,2'-dithiophene)}, poly{2,5-bis(2-octyldodecyl)-3,6-di(thiophen-2-yl)dionepyrrolo[3,4-c]pyrrole-1,4-dione-alt-thiophene[3,2-b]thiophene}, poly(quaterthiopheneacetic acid diketopyrrole), poly{2,2'-(2,5-bis(2-octyldodecyl)-3,6-isoindigo-alt-thiophene-2, any one of poly{(4,4,9,9-tetrahexadecyl-indacen-[1,2-b:5,6-b']dithiophene-2,7-diyl)-alt-(benzo[c][1,2,5]thiadiazole-4,7-diyl)}, poly(3-hexylthiophene), poly{[N,N9-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,59-(2,29-thiophene)}; The unsaturated rubber is natural rubber, styrene-butadiene rubber or chloroprene rubber; The saturated rubber is butyl rubber, ethylene propylene rubber or polydimethylsiloxane; The thermoplastic elastomer is any one of hydrogenated styrene-butadiene block copolymer, polyacrylate rubber, polyurethane elastomer, polyolefin elastomer and polyether ester elastomer.

4. The high-density stretchable organic phototransistor array according to any one of claims 1 to 3, characterized in that: The stretchable substrate and the stretchable insulating layer are both made of an elastomeric polymer; The elastomeric polymer is any one of unsaturated rubber, saturated rubber and thermoplastic elastomer; The unsaturated rubber is natural rubber, styrene-butadiene rubber or chloroprene rubber; The saturated rubber is butyl rubber, ethylene propylene rubber or polydimethylsiloxane; The thermoplastic elastomer is any one of hydrogenated styrene-butadiene block copolymer, polyacrylate rubber, polyurethane elastomer, polyolefin elastomer and polyether ester elastomer.

5. The high-density stretchable organic phototransistor array according to any one of claims 1 to 4, characterized in that: The thickness of the stretchable substrate is 500 μm to 2 mm; The thickness of the stretchable insulating layer is 1.0 μm to 1.5 μm; The thickness of the stretchable polymer semiconductor layer is 50-150 nm.

6. The high-density stretchable organic phototransistor array according to any one of claims 1 to 5, characterized in that: The stretchable gate electrode and the stretchable source and drain microelectrodes are all made of intrinsic stretchable conductive materials; The intrinsically stretchable conductive material is any one of metallic single-walled carbon nanotubes, metal nanowires, liquid metals, conductive polymers and two-dimensional conductive materials; The conductivity of the stretchable gate electrode and the stretchable source and drain microelectrodes is 5×10 3 ~5×10 5 S cm -1 .

7. The method for preparing a high-density stretchable organic phototransistor array according to any one of claims 1 to 6, characterized in that: The steps include: S1. preparing the stretchable substrate, the stretchable insulating layer, the stretchable polymer semiconductor layer and the stretchable gate electrode on a substrate respectively; S2, spin coating a photoresist on the substrate, followed by photolithography and development to form a patterned photoresist; Depositing a sacrificial layer on the patterned photoresist, preparing a stretchable electrode on the sacrificial layer, peeling off the photoresist portion, leaving the patterned microelectrode, and obtaining the stretchable source and drain microelectrodes; S3. According to the structure of the stretchable organic phototransistor, the components constituting the stretchable organic phototransistor are transferred and bonded to obtain the high-density stretchable organic phototransistor array.

8. The method for preparing a high-density stretchable organic phototransistor array according to claim 7, characterized in that: In steps S1 and S2, the substrate is any one of a silicon wafer, a SiO2-Si silicon substrate, quartz, glass, PET plastic, a sapphire substrate, ceramics, metal and cemented carbide; In step S1, the stretchable polymer semiconductor layer is prepared by spin coating a polymer solution and then annealing; The solvent for preparing the polymer solution of the stretched polymer semiconductor layer is at least one of chlorobenzene, dichlorobenzene, chloroform and xylene; The total mass concentration of the polymer solution for preparing the stretched polymer semiconductor layer is 5 mg / ml to 30 mg / ml; The spin coating speed for preparing the stretched polymer semiconductor layer is 1000-4000 r / min, and the spin coating time is 40 s-1 min; The annealing temperature for preparing the stretched polymer semiconductor layer is 100 to 250° C.; In step S2, the sacrificial layer is a small molecule film, a hydrolyzable or degradable polymer film; The thickness of the sacrificial layer is 30 to 300 nm; The small molecules in the small molecule film are selected from metal halides; The polymer in the hydrolyzable or degradable polymer film is selected from any one of dextran, polyvinyl alcohol, polyacrylamide and polycarbonate; The small molecule film is prepared by vacuum evaporation at a rate of The hydrolyzable or degradable polymer film is prepared by spin coating a polymer solution and then annealing; The solvent for preparing the hydrolyzable or degradable polymer solution is any one of deionized water, tetrahydrofuran and chloroform; The concentration of the hydrolyzable or degradable polymer solution is prepared to be 10 mg / ml to 100 mg / ml; The spin coating speed for preparing the hydrolyzable or degradable polymer solution is 3000-6000 r / min, and the spin coating time is 40 s-1 min; The annealing temperature for preparing the hydrolyzable or degradable polymer solution is 40 to 200° C.; The stretchable source and drain microelectrodes are transferred by mechanical stripping, thermal stripping or hydrolysis release.

9. Use of the high-density stretchable organic phototransistor array according to any one of claims 1 to 6 in preparing wearable flexible photodetectors or imaging.

10. The use according to claim 9, characterized in that: The wearable photoelectric detector or the imaging detectable light has a wavelength band of X-rays, ultraviolet light, visible light or near-infrared light.

Images