Balancing the Photo‐Induced Carrier Transport Behavior at Two Semiconductor Interfaces for Dual‐Polarity Photodetection

• DOI: 10.1002/adfm.202202524
• Publication Date: 2022-04-14T06:13:18Z
• Authors: Shi Fang; Danhao Wang; Yang Kang; Xin Liu; Yuanmin Luo; Kun Liang; Liuan Li; Huabin Yu; Haochen Zhang; Muhammad Hunain M...; Boyang Liu; Zhenghui Liu; Haiding Sun
• Keywords: Photocurrent; Charge carrier; Photodetection; Band bending; Electron Mobility

Abstract The carrier transport dynamics at the surface/interface of semiconductors determine electronic and optical properties devices. Thus, precise control their dynamic processes while understanding nature these characteristics is crucial for modulating device functionalities. Here, a photoelectrochemical‐type photosensor built using monocrystalline p‐GaN nanowires on Si platform, which unambiguously exhibits either positive or negative photocurrent upon different light illumination. Such dual‐polarity photocurrents are attributed to photogenerated‐carrier‐transport competition two interfaces: GaN/electrolyte GaN/Si interface. Particularly, rational Pt decoration successfully accelerates migration interface that breaks original balance transport. This mechanism further elaborated by Kelvin‐probe‐force‐microscopy characterization, intuitively reveals impact nanowires’ surface band bending consequent interfaces. These insights into shed achieving multi‐functional PEC devices simple semiconductor architectures.