Chen, Renfeng; Chen, Kaixuan; Ran, Junxue; Song, Yijian; Qu, Xiaodong; Yang, Kewei; Ji, Xiaoli; Wang, Junxi; Wei, Tongbo

Source: Semiconductor Science and Technology, v 39, n 7, July 2024; ISSN: 02681242, E-ISSN: 13616641; DOI: 10.1088/1361-6641/ad54e8; Article number: 075022; Publisher: Institute of Physics

Author affiliation:

Research and Development Center for Wide Bandgap Semiconductors, Institute of Semiconductors, Chinese Academy of Sciences, Beijing; 100083, China

Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing; 100049, China

Xiamen Changelight Co., Ltd, Fujian Province, Xiamen; 361101, China

Abstract:

We have demonstrated an effective piezoelectric polarized interface modulation in a GaN/Ti Schottky structure and fabricated a flexible GaN-based sensor using a double-transfer method. Chemical etching of the Ni sacrificial layer successfully removes the temporary substrate without damaging the metal electrodes. The fabricated flexible GaN-based sensor, with top and bottom Ti metal Schottky contacts, exhibits a current on/off characteristic under external strain. Specifically, the current shows a 53.9% reduction under 2.3% tensile strain and a 67.8% enhancement under −2.3% compressive strain at a 5 V bias voltage. It was found that the light/dark current ratio in the GaN/Ti Schottky junction significantly increases near zero-bias voltage under 2.3% tensile strain, likely indicating an enhanced built-in piezoelectric polarized field at the interface. This work advances the study of flexible sensors based on wurtzite III-V nitrides for wearable electronics and optoelectronics.