Material Design of p-Type Transparent Amorphous Semiconductor, Cu-Sn-I

Taehwan Jun; Junghwan Kim; Masato Sasase; Hideo Hosono

doi:10.1002/adma.201706573

Material Design of p-Type Transparent Amorphous Semiconductor, Cu-Sn-I

Adv Mater. 2018 Mar;30(12):e1706573. doi: 10.1002/adma.201706573. Epub 2018 Jan 30.

Authors

Taehwan Jun¹, Junghwan Kim², Masato Sasase², Hideo Hosono^{1

2}

Affiliations

¹ Laboratory for Materials and Structures, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.
² Materials Research Center for Element Strategy, Tokyo Institute of Technology, Mailbox SE-1, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.

PMID: 29380430
DOI: 10.1002/adma.201706573

Abstract

Transparent amorphous semiconductors (TAS) that can be fabricated at low temperature are key materials in the practical application of transparent flexible electronics. Although various n-type TAS materials with excellent performance, such as amorphous In-Ga-Zn-O (a-IGZO), are already known, no complementary p-type TAS has been realized to date. Here, a material design concept for p-type TAS materials is proposed utilizing the pseudo s-orbital nature of spatially spreading iodine 5p orbitals and amorphous Sn-containing CuI (a-CuSnI) thin film is reported as an example. The resulting a-CuSnI thin films fabricated by spin coating at low temperature (140 °C) have a smooth surface. The Hall mobility increases with the hole concentration and the largest mobility of ≈9 cm² V^-1 s^-1 is obtained, which is comparable with that of conventional n-type TAS.

Keywords: amorphous p-type Cu-Sn-I semiconductors; flexible electronics; material design; solution process.