[TuP3A] Epitaxy and process

[TuP3A-07] Direct Quantitative Visualization of Band Profile across III-V Devices using Kelvin Probe Force Microscopy

〇Nobuyuki Ishida¹, Takuya Kawazu¹, Akihiro Ohtake¹, Takaaki Mano¹ (1. National Inst. for Materials Sci. (NIMS) (Japan))

Understanding and engineering band alignment at heterointerfaces is critical for controlling carrier transport in semiconductor devices. However, direct visualization of band diagrams under operating conditions remains challenging, as existing techniques often lack the combined capabilities of high spatial resolution, quantitative accuracy, and operando compatibility. Here, we present a comprehensive operando mapping of the band diagram evolution in a III-V infrared sensor using ultrahigh-vacuum Kelvin probe force microscopy. The measurements reveal pronounced band bending, Fermi-level pinning, band offset shifts, and charge accumulation at relevant interfaces. These findings elucidate the origins of the high infrared sensitivity of the device and suggest design strategies for performance enhancement through interface engineering. Our approach establishes a robust experimental platform for probing and tailoring complex heterostructure band alignments in next-generation optoelectronic devices.