A method of manufacturing an x-ray detector

Abstract

The application discloses a manufacturing method of an X-ray detector. The method adopts an anisotropic conductive adhesive as a bonding layer to heterogeneously integrate a perovskite layer and an ITO glass substrate, so that the problem of perovskite layer peeling caused by different thermal expansion coefficients of the perovskite layer and the substrate can be well avoided. Meanwhile, the ACA adhesive is used as the bonding layer, stronger bonding force can be provided, and the manufactured device has better mechanical stability.

Description

Technical Field

[0001] This invention relates to the field of X-ray detector technology, and more particularly to a method for manufacturing an X-ray detector. Background Technology

[0002] Flat panel X-ray detectors play a crucial role in various applications such as medical imaging, non-destructive testing, and security inspection. Halide perovskites, due to their high X-ray blocking ability, low trap density, and long carrier lifetime, hold promise for use in semiconductor direct X-ray detectors. Currently, extensively studied halide perovskites have demonstrated significant advantages and broad prospects in semiconductor direct detection. There are currently two main methods for fabricating semiconductor planar array detectors: one is to directly and uniformly fabricate the X-ray absorbing layer on the substrate, and the other is to combine the X-ray absorbing layer with the substrate through heterogeneous integration. However, due to the significant difference in thermal expansion coefficients between the perovskite layer and the substrate, detachment or porosity can easily occur between the substrate and the perovskite layer during annealing due to expansion and contraction, severely affecting its application. Furthermore, some substrates are not heat-resistant, which greatly limits the annealing temperature of the perovskite layer. Summary of the Invention

[0003] This invention provides a method for manufacturing an X-ray detector, which solves the technical problem in the prior art where expansion and contraction during annealing can easily cause the substrate and perovskite layer to detach or form pores.

[0004] This invention provides a method for manufacturing an X-ray detector, comprising:

[0005] Immerse the ITO glass in acetone for cleaning;

[0006] Weigh FAI, MAI, and PbI2 according to a preset ratio and place them into a ball mill jar. Add an antisolvent to the ball mill jar and ball mill.

[0007] The slurry after ball milling is dried.

[0008] The dried powder is placed into a tablet press to form a perovskite layer;

[0009] Apply ACA adhesive to the cleaned ITO glass;

[0010] The perovskite layer is applied to ITO glass coated with ACA adhesive.

[0011] The ITO glass covered with a perovskite layer was annealed and then cooled to room temperature.

[0012] Specifically, before immersing the ITO glass in acetone for cleaning, the procedure further includes:

[0013] Add deionized water and detergent to the ITO glass, ultrasonically clean for 30 minutes, and then rinse with deionized water.

[0014] Specifically, after immersing the ITO glass in acetone for cleaning, the process further includes:

[0015] After cleaning, the ITO glass was rinsed with anhydrous ethanol, dried with a nitrogen gun, and then treated with plasma for 5 minutes.

[0016] Specifically, the step of adding antisolvent to the ball milling jar for ball milling includes:

[0017] Ethyl acetate antisolvent was added to the ball mill jar, and the mixture was ball milled at 600 r / min for 12 h.

[0018] Specifically, the drying process for the slurry after ball milling includes:

[0019] The ball-milled slurry was transferred to a vacuum drying oven and dried overnight at 80°C.

[0020] Specifically, after applying the ACA adhesive to the cleaned ITO glass, the process further includes:

[0021] Use a scraper to smooth the ACA adhesive.

[0022] Specifically, annealing the ITO glass coated with the perovskite layer and then cooling it to room temperature includes:

[0023] The ITO glass covered with the perovskite layer was transferred to a hot stage at 150°C and annealed for 15 minutes, then allowed to cool naturally to room temperature.

[0024] One or more technical solutions provided in this invention have at least the following technical effects or advantages:

[0025] This invention employs anisotropic conductive adhesive (ACA adhesive) as a bonding layer to heterogeneously integrate the perovskite layer with an ITO glass substrate, effectively preventing the perovskite layer from detaching due to the difference in thermal expansion coefficients between the perovskite layer and the substrate. Furthermore, using ACA adhesive as the bonding layer provides stronger adhesion, resulting in better mechanical stability of the fabricated device. Attached Figure Description

[0026] Figure 1 A flowchart illustrating the manufacturing method of an X-ray detector provided in an embodiment of the present invention;

[0027] Figure 2 This is an optical microscope image of the ACA adhesive in an embodiment of the present invention;

[0028] Figure 3 The image shows the tensile stress test results of the ITO glass / ACA adhesive and the ITO glass / ACA adhesive / perovskite layer prepared according to the embodiments of the present invention.

[0029] Figure 4 This is a SEM cross-sectional view of the ITO glass / ACA adhesive / perovskite layer structure prepared according to the embodiments of the present invention. Detailed Implementation

[0030] This invention provides a method for manufacturing an X-ray detector, which solves the technical problem in the prior art where expansion and contraction during annealing can easily cause the substrate and perovskite layer to detach or form pores.

[0031] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0032] See Figure 1 The method for manufacturing an X-ray detector provided in this embodiment of the invention includes:

[0033] Step S110: Immerse the ITO glass in acetone for cleaning;

[0034] This step is explained in detail: the ITO glass is immersed in acetone for cleaning, including:

[0035] Immerse the ITO glass in acetone and ultrasonically clean it for 30 minutes.

[0036] To more thoroughly clean impurities from the ITO glass surface, the following steps are included before immersing the ITO glass in acetone for cleaning:

[0037] Place the ITO glass on a glass cleaning rack, add deionized water and detergent to the ITO glass, ultrasonically clean for 30 minutes, then rinse with deionized water and place in anhydrous ethanol for later use.

[0038] To improve the hydrophilicity of ITO glass, after immersing the ITO glass in acetone for cleaning, the following steps are also taken:

[0039] After cleaning, the ITO glass was rinsed with anhydrous ethanol, dried with a nitrogen gun, and then treated with plasma for 5 minutes.

[0040] Step S120: Weigh FAI, MAI, and PbI2 according to a preset ratio and place them in a ball mill jar. Add an antisolvent to the ball mill jar and ball mill. Specifically, the perovskite layer uses FAI. 0.5 MA 0.5To prevent the influence of water and oxygen in the air on the PbI3 system, high-purity FAI, MAI, and PbI2 were weighed in a glove box at a certain molar ratio and placed into a ball mill jar.

[0041] Specifically, adding the antisolvent to the milling jar and milling it includes:

[0042] Add ethyl acetate as a solvent to the ball mill jar and ball mill for 12 hours at 600 r / min.

[0043] Step S130: Dry the slurry after ball milling;

[0044] This step is described in detail, involving the drying of the slurry after ball milling, including:

[0045] After ball milling, the slurry is transferred to a vacuum drying oven and dried overnight at 80°C.

[0046] Step S140: Place the dried powder into a tablet press to form a perovskite layer;

[0047] This step is described in detail: the dried powder is placed into a tablet press to form a perovskite layer, including:

[0048] Take 2g of the dried powder and place it into a tablet press. Compress it at 15MPa for 120s to form tablets measuring 2.5×2.5cm. 2 The perovskite layer is ready for use.

[0049] Step S150: Place the ITO glass on the worktable and apply ACA adhesive to the cleaned ITO glass;

[0050] To ensure that the ACA adhesive is evenly spread on the ITO glass, after applying the ACA adhesive to the cleaned ITO glass, the following steps are also included:

[0051] Use a micron-sized scraper to smooth out the ACA adhesive.

[0052] Step S160: Cover the perovskite layer onto the ITO glass with ACA adhesive, and gently press the perovskite layer with your hand to ensure that the perovskite layer and ACA adhesive are in uniform contact.

[0053] Step S170: Anneal the ITO glass covered with the perovskite layer, and then cool it to room temperature.

[0054] This step is described in detail, involving annealing the ITO glass coated with a perovskite layer and then cooling it to room temperature, including:

[0055] The ITO glass covered with a perovskite layer was transferred to a hot stage at 150°C and annealed for 15 minutes, then allowed to cool naturally to room temperature.

[0056] See Figure 2 The conductive particles of the ACA adhesive used in this embodiment of the invention are nickel particles with a diameter of approximately 1.5 μm, surrounded by polymer. See also Figure 3 The ACA adhesive and the ITO glass substrate can withstand a tensile stress of about 400N, and even after the perovskite layer is covered, it can still withstand a tensile force of about 170N. Figure 4 A cross-sectional SEM image of the ITO glass / ACA adhesive / perovskite structure prepared by the embodiment of the present invention is shown, which shows that the thickness of the ACA adhesive is about 8 μm.

[0057] This invention combines an annealed perovskite layer and an ITO glass substrate with an adhesive layer, enabling the fabrication of an X-ray flat panel detector with low dark current and high spatial resolution. This not only perfectly solves the problem of perovskite layer detachment caused by different coefficients of thermal expansion during annealing, but also allows the perovskite layer to be directly heated to a suitable temperature, thus having broad application prospects.

[0058] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0059] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for manufacturing an X-ray detector, characterized in that, include: Immerse the ITO glass in acetone for cleaning; Weigh FAI, MAI, and PbI2 according to a preset ratio and place them into a ball mill jar. Add an antisolvent to the ball mill jar and ball mill. The slurry after ball milling is dried. The dried powder is placed into a tablet press to form a perovskite layer; Apply ACA adhesive to the cleaned ITO glass; The perovskite layer is applied to ITO glass coated with ACA adhesive. The ITO glass covered with a perovskite layer was annealed and then cooled to room temperature.

2. The method for manufacturing an X-ray detector as described in claim 1, characterized in that, Before immersing the ITO glass in acetone for cleaning, the procedure further includes: Add deionized water and detergent to the ITO glass, ultrasonically clean for 30 minutes, and then rinse with deionized water.

3. The method for manufacturing an X-ray detector as described in claim 1, characterized in that, After immersing the ITO glass in acetone for cleaning, the process further includes: After cleaning, the ITO glass was rinsed with anhydrous ethanol, dried with a nitrogen gun, and then treated with plasma for 5 minutes.

4. The method for manufacturing an X-ray detector as described in claim 1, characterized in that, The step of adding antisolvent to the ball milling jar for ball milling includes: Ethyl acetate antisolvent was added to the ball mill jar, and the mixture was ball milled at 600 r / min for 12 h.

5. The method for manufacturing an X-ray detector as described in claim 1, characterized in that, The drying process of the slurry after ball milling includes: The ball-milled slurry was transferred to a vacuum drying oven and dried overnight at 80 °C.

6. The method for manufacturing an X-ray detector as described in claim 1, characterized in that, After applying the ACA adhesive to the cleaned ITO glass, the process further includes: Use a scraper to smooth the ACA adhesive.

7. The method for manufacturing an X-ray detector as described in claim 1, characterized in that, The step of annealing the ITO glass coated with a perovskite layer and then cooling it to room temperature includes: The ITO glass covered with the perovskite layer was transferred to a hot stage at 150 °C and annealed for 15 min, then allowed to cool naturally to room temperature.

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