Halide Perovskite Nanopillar Photodetector

• Published in: ACS nano Vol. 12; no. 8; pp. 8564 - 8571
• Main Authors: Chun, Do Hyung, Choi, Young Jin, In, Yongjae, Nam, Jae Keun, Choi, Yung Ji, Yun, Sangeun, Kim, Wook, Choi, Dukhyun, Kim, Dongho, Shin, Hyunjung, Cho, Jeong Ho, Park, Jong Hyeok
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 28-08-2018
• Subjects: perovskite; nanoimprinting; nanopillar; photodetector; nanopattern
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/acsnano.8b04170

Numerous studies have reported the use of halide perovskites as highly functional light-harvesting materials. The development of optimized compositions and deposition approaches has led to impressive improvements; however, no noticeable breakthrough in performance has been observed for these materials recently. Here, a breakthrough that enables the fabrication of vertically grown halide perovskite (VGHP) nanopillar photodetectors via a nanoimprinting crystallization technique is demonstrated. We used engraved nanopatterned polymer stamps to form VGHP nanopillars during the pressurized crystallization of the softly baked gel state of a methylammonium lead iodide (CH3NH3PbI3, denoted MAPI) film. The VGHP films exhibit much lower defect density and higher conductivity, as supported by current–voltage characteristic measurements and conductive atomic force microscopy measurements. Ultimately, two-terminal lateral photodetectors based on the VGHP nanopillar films show a greatly enhanced photoresponse compared with flat film-based photodetectors. We expect that the deposition method presented here will help surpass the technical limits and contribute to further improvements in various halide-perovskite-based devices.