US 12,435,442 B2
Strain engineering and epitaxial stabilization of halide perovskites
Sheng Xu, La Jolla, CA (US); Yimu Chen, La Jolla, CA (US); and Yusheng Lei, La Jolla, CA (US)
Assigned to THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, Oakland, CA (US)
Appl. No. 17/619,728
Filed by THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, Oakland, CA (US)
PCT Filed Jun. 29, 2020, PCT No. PCT/US2020/040083
§ 371(c)(1), (2) Date Dec. 16, 2021,
PCT Pub. No. WO2020/264483, PCT Pub. Date Dec. 30, 2020.
Claims priority of provisional application 62/868,370, filed on Jun. 28, 2019.
Prior Publication US 2022/0320433 A1, Oct. 6, 2022
Int. Cl. C30B 29/12 (2006.01); C30B 19/08 (2006.01); C30B 19/10 (2006.01); C30B 19/12 (2006.01); C30B 29/54 (2006.01); H10K 30/20 (2023.01); H10K 71/12 (2023.01); H10K 85/50 (2023.01); H01G 9/20 (2006.01); H10K 85/30 (2023.01)
CPC C30B 29/12 (2013.01) [C30B 19/08 (2013.01); C30B 19/10 (2013.01); C30B 19/12 (2013.01); C30B 29/54 (2013.01); H10K 30/20 (2023.02); H10K 71/12 (2023.02); H10K 85/50 (2023.02); H01G 9/2009 (2013.01); H10K 85/30 (2023.02)] 21 Claims
OG exemplary drawing
 
1. A method of forming a device, comprising:
choosing a first halide perovskite material from which a halide perovskite thin film is to be formed from a solvent-based liquid solution;
choosing an epitaxial substrate formed from a second halide perovskite material;
fabricating a patterned mask to control solvent-based liquid solution growth behavior of the halide perovskite thin film on the epitaxial substrate; and
epitaxially forming the halide perovskite thin film on the epitaxial substrate from the first halide perovskite material, the first halide perovskite material being α-FAPbI3, where FA is formamidinium, wherein the epitaxial substrate is chosen such that the halide perovskite thin film formed on the substrate has a selected value of at least one property, the property being selected from the group including crystal structure stability, charge carrier mobility and band gap, and wherein the epitaxially forming includes epitaxially forming an elastically strained halide perovskite thin film on the epitaxial substrate from the first halide perovskite material, wherein the elastically strained halide perovskite thin film has a thickness less than 100 nm, and the first halide perovskite has a compressive strain between 0% and −2.4%, wherein the elastically strained halide perovskite thin film has a room temperature bandgap between 1.488 eV and 1.523 eV, an External Quantum Efficiency (EQE) between 3×10−4%, and 6×10−4% and a time-of-flight electron mobility between 20 cm2V−1s−1 and 30 cm2V−1s−1.