Charge-trap-assisted flexible nonvolatile memory applications using oxide-semiconductor thin-film transistors

• Published in: Japanese Journal of Applied Physics Vol. 58; no. 9; pp. 90601 - 90624
• Main Authors: Yoon, Sung-Min, Yang, Ji-Hee, Kim, Hyeong-Rae, Jang, Hye-Won, Park, Min-Ji, Kim, So-Jung, Yun, Da-Jeong, Na, So-Yeong, Yoon, So-Jung, Son, Min-Tae, Ko, Seung-Bo, Kwak, Sol-Mi
• Format: Journal Article
• Language: English
• Published: Tokyo IOP Publishing 01.09.2019; Japanese Journal of Applied Physics
• Subjects: Computer memory; Electronic devices; Glass substrates; Indium gallium zinc oxide; Memory devices; Polyethylene naphthalate; Random access memory; Semiconductor devices; Thin film transistors; Transistors; Zinc oxide
• ISSN: 0021-4922; 1347-4065
• DOI: 10.7567/1347-4065/ab09e4

We introduce mechanically flexible nonvolatile memory thin-film transistors (MTFTs) for future highly functional flexible and stretchable electronic devices and systems. The proposed memory devices are uniquely composed of oxide-semiconductor thin films and operated with charge-trap and detrap mechanisms for nonvolatile memory operations. Charge-trap-assisted MTFTs (CT-MTFTs) using In-Ga-Zn-O active and ZnO charge-trap layers are designed and fabricated on flexible poly(ethylene naphthalate) and colorless polyimide films prepared on carrier glass substrates. We describe the fabrication processes and evaluation methodologies for realizing flexible CT-MTFTs in a detailed way and discuss related technical issues. The device characteristics and memory performance of the fabricated flexible CT-MTFTs, including when the devices are mechanically strained, are extensively discussed. We also propose further improvements for remaining issues on device performance from the viewpoints of memory operations and mechanical flexibility.