Imaging hot photocarrier transfer across a semiconductor heterojunction with ultrafast electron microscopy.

ABSTRACT: Semiconductor heterojunctions have gained significant attention for efficient optoelectronic devices owing to their unique interfaces and synergistic effects. Interaction between charge carriers with the heterojunction plays a crucial role in determining device performance, while its spatial-temporal mapping remains lacking. In this study, we employ scanning ultrafast electron microscopy (SUEM), an emerging technique that combines high spatial-temporal resolution and surface sensitivity, to investigate photocarrier dynamics across a Si/Ge heterojunction. Charge dynamics are selectively examined across the junction and compared to far bulk areas, through which the impact of the built-in potential, band offsets, and surface effects is directly visualized. In particular, we find that the hete

SUBMITTER: Shaheen BS 

PROVIDER: S-EPMC11468150 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature