Improved Process Stability and Light Detection in Phototransistors via Inverted MoS<inf>2</inf>/a-IGZO Heterojunction Integration

Jin, Jidong; Kang, Kumin; Xiao, Zhenyuan; Zhang, Jiawei; Kim, Tae Yeon; Lee, Hyun Seok; Kim, Jaekyun

Abstract

The integration of molybdenum disulfide (MoS2) with other semiconductors to form heterojunction phototransistors demonstrates potential for optoelectronic applications due to their strong interaction with light and tunable bandgaps. Conventionally, bottom-gate phototransistors based on MoS2 and amorphous indium–gallium–zinc oxide (a-IGZO) are fabricated by deposition of the a-IGZO film on the gate dielectric, followed by deposition of the MoS2 film, resulting in a MoS2/a-IGZO heterojunction. In this study, an inverted MoS2/a-IGZO (or denoted as a-IGZO/MoS2) heterojunction integration for bottom-gate phototransistors, where the MoS2 film is deposited on the gate dielectric first, followed by the deposition of the a-IGZO film, is presented. This configuration is designed to enhance the processability and electrical properties of the phototransistor. Under visible light exposure with a low optical power density of 5.3 μW cm−2, the a-IGZO/MoS2 heterojunction phototransistor demonstrates significantly improved photoresponsivity (1.6, 2.8, and 17 A W−1 at 635, 520, and 405 nm wavelengths, respectively) compared to the MoS2 single-channel phototransistor. Time-dependent photoresponse measurements reveal that the a-IGZO/MoS2 heterojunction phototransistor responds more quickly to light changes and generates a tenfold-greater photocurrent than that of the MoS2 single-channel phototransistor.

Citation

Jin, J., Kang, K., Xiao, Z., Zhang, J., Kim, T. Y., Lee, H. S., & Kim, J. (2025). Improved Process Stability and Light Detection in Phototransistors via Inverted MoS2/a-IGZO Heterojunction Integration. physica status solidi (a) – applications and materials science, 222(3), Article 2400536. https://doi.org/10.1002/pssa.202400536

• Journal Article Type: Article
• Acceptance Date: Sep 13, 2024
• Online Publication Date: Oct 8, 2024
• Publication Date: Feb 1, 2025
• Deposit Date: Feb 25, 2025
• Journal: Physica Status Solidi (A) Applications and Materials Science
• Print ISSN: 1862-6300
• Electronic ISSN: 1862-6319
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 222
• Issue: 3
• Article Number: 2400536
• DOI: https://doi.org/10.1002/pssa.202400536
• Public URL: https://durham-repository.worktribe.com/output/3510711