# US 9,520,437 B2 · Flexible APS X-ray imager with MOTFT pixel readout and a pin diode sensing element > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,520,437 B2 - Document ID: US9520437B2 - Status: Granted - Kind: B2 - Application number: 14/460,054 - Filed: 2014-08-14 - Published: 2016-02-18 - Granted: 2016-12-13 - Earliest claimed: 2014-08-14 - Assignees: Cbrite Inc. - Applicants: Chan-Long Shieh; Gang Yu - Inventors: Chan-Long Shieh; Gang Yu - Web page: https://patentgrep.com/patent/US9520437B2 ## CPC - H10F 39/1898: {Indirect radiation image sensors, e.g. using luminescent members} - H10F 39/016: {of thin-film-based image sensors} - H10F 39/8037: {the integrated elements comprising a transistor} - H10F 39/189: {X-ray, gamma-ray or corpuscular radiation imagers} - H10K 30/40: comprising a p-i-n structure, e.g. having a perovskite absorber between p-type and n-type charge transport layers - H10K 39/30: Devices controlled by radiation - H10K 39/36: Devices specially adapted for detecting X-ray radiation - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES ## Abstract A method of fabricating an X-ray imager including the steps of forming an etch stop layer on a glass substrate and depositing a stack of semiconductor layers on the etch stop layer to form a sensor plane. Separating the stack into an array of PIN photodiodes. Depositing a layer of insulating material on the array to form a planarized surface and forming vias through the insulating layer into communication with an upper surface of each photodiode and forming metal contacts on the planarized surface through the vias in contact with each photodiode. Fabricating an array of MOTFTs in an active pixel sensor configuration backplane on the planarized surface and in electrical communication with the contacts, to provide a sensor plane/MOTFT backplane interconnected combination. Attaching a flexible support carrier to the MOTFT backplane and removing the glass substrate. A scintillator is then laminated on the array of photodiodes. ## Claims ### Claim 1 A method of fabricating an X-ray imager comprising the steps of: providing a rigid support member with a surface; forming an etch stop layer on the surface of the rigid support member; depositing sensing element blanket layers on the etch stop layer; separating the sensing element blanket layers into an array of sensing elements; depositing a layer of insulating material on the array of sensing elements to form a planarized surface; forming contacts on the planarized surface with individual sensing elements in the array through the layer of insulating material; positioning a MOTFT backplane on the planarized surface and in electrical communication with the contacts, to provide a sensor plane/MOTFT backplane interconnected combination; attaching a support carrier to the MOTFT backplane; removing the rigid support member; and laminating a scintillator on the array of sensing elements. ### Claim 2 (depends on 1) A method as claimed in claim 1 wherein the step of depositing sensing element blanket layers on the etch stop layer includes depositing multiple semiconductor layers, forming a PIN photodiode plane. ### Claim 3 (depends on 2) A method as claimed in claim 2 wherein the step of forming the PIN photodiode plane includes process temperatures higher than process temperatures included in the step of positioning the MOTFT backplane. ### Claim 4 (depends on 2) A method as claimed in claim 2 wherein the step of depositing sensing element blanket layers, the multiple semiconductor layers include at least one of amorphous silicon, amorphous germanium, and amorphous selenium. ### Claim 5 (depends on 2) A method as claimed in claim 2 wherein the step of depositing sensing element blanket layers, the multiple semiconductor layers comprise compound semiconductor materials including at least one of Zn—O, In—Zn—O, Ti—O, Ta—O, W—O, Zr—O, Cd—S, Cd—O, Cu—O, Cu—S, Cu—In—O, Cu—In—Se, Cu—In—S, Cu—Cd—O, Cu—Cd—Se, Cu—Cd—S, Cu—Ga—S, Cu—Ga—O, Cu—Ga—Se, Cu—In—Ga—Se, Cu—In—Ga—S, Mo—O, AgxMoO3-x, and combinations in blend or in stack form. ### Claim 6 (depends on 1) A method as claimed in claim 1 wherein the step of depositing sensing element blanket layers on the etch stop layer includes depositing a first p or n doped layer, an intrinsic layer, and a second n or p doped layer, forming a PIN photodiode plane. ### Claim 7 (depends on 6) A method as claimed in claim 6 wherein the step of separating the sensing element blanket layers into an array of sensing elements includes patterning the second n or p doped layer to define individual PIN photodiodes. ### Claim 8 (depends on 7) A method as claimed in claim 7 wherein the step of separating the sensing element blanket layers into an array of sensing elements includes further patterning the intrinsic layer to define individual PIN photodiodes. ### Claim 9 (depends on 1) A method as claimed in claim 1 wherein the step of depositing a layer of insulating material includes depositing material including one of organic or inorganic insulating material including SU-8, polyimide, JSR PCS548, AZ SOG series, silane or siloxane based photo-patternable polymers, SiN, SiON, SiOx, or combinations thereof in blend form or in stack multiple sublayers. ### Claim 10 (depends on 9) A method as claimed in claim 9 wherein the step of depositing the layer of insulating material including one of organic or inorganic insulating material includes depositing an inorganic sublayer in contact with the PIN sensing elements and a photo-patternable organic insulator layer in contact with the MOTFT backplane. ### Claim 11 (depends on 1) A method as claimed in claim 1 wherein the step of forming the etch stop layer includes forming a layer including one of a noble metal and poly-Si. ### Claim 12 (depends on 11) A method as claimed in claim 11 wherein the step of forming the etch stop layer including one of a noble metal and poly-Si includes forming the etch stop layer with a thickness of less than 200 nm. ### Claim 13 (depends on 1) A method as claimed in claim 1 wherein the step of forming contacts on the planarized surface includes forming vias through the layer of insulating material and introducing metal contacts through the vias. ### Claim 14 (depends on 1) A method as claimed in claim 1 wherein the step of positioning the MOTFT backplane on the planarized surface includes fabricating an array of MOTFTs in an active pixel sensor configuration. ### Claim 15 (depends on 14) A method as claimed in claim 14 wherein the step of fabricating the array of MOTFTs in the active pixel sensor configuration includes forming each active pixel sensor with signal amplification. ### Claim 16 (depends on 1) A method as claimed in claim 1 wherein the step of attaching the support carrier includes attaching a flexible support carrier. ### Claim 17 (depends on 1) A method as claimed in claim 1 wherein the step of providing the rigid support member includes providing a glass substrate. ### Claim 18 (depends on 17) A method as claimed in claim 17 wherein the step of removing the rigid support member includes etching the glass substrate using HF. ### Claim 19 (depends on 1) A method as claimed in claim 1 further including a step of removing the etch stop layer subsequent to the step of removing the rigid support member. ### Claim 20 A method of fabricating an X-ray imager comprising the steps of: providing a glass substrate with a surface; forming an etch stop layer including one of a noble metal and poly-Si on the surface of the glass substrate; depositing a stack of elemental or compound semiconductor layers on the etch stop layer, the stack including a first p or n doped layer, an intrinsic layer, and a second n or p doped layer, forming a PIN photodiode plane; separating the stack of semiconductor layers into an array of PIN photodiodes; depositing a layer of insulating material on the array of sensing elements to form a planarized surface and forming vias through the planarizing layer into communication with an upper surface of each PIN photodiode in the array of PIN photodiodes; forming metal contacts on the planarized surface and through the vias in contact with the upper surface of each PIN photodiode in the array of PIN photodiodes; fabricating an array of MOTFTs in an active pixel sensor configuration backplane on the planarized surface and in electrical communication with the contacts, to provide a sensor plane/MOTFT backplane interconnected combination; attaching a flexible support carrier to the MOTFT backplane; removing the glass substrate; and laminating a scintillator on the array of PIN photodiodes.