Abstract
Vertical electronic transport in periodic GaN/AlGaN multiple-quantum-well structures grown on free-standing GaN substrates is investigated. Highly nonlinear current-voltage characteristics are measured, displaying a clear transition from a high-resistance state near zero applied bias to a low-resistance state as the voltage is increased. The measurement results, including their temperature dependence and the variations in turn-on voltage with subband structure and bias polarity are in full agreement with a picture of sequential tunneling through the ground-state subbands of adjacent coupled quantum wells. Scattering-assisted tunneling due to interface roughness or structural defects appears to be the dominant transport mechanism. The potential role of photon-assisted tunneling is also investigated.
Original language | English (US) |
---|---|
Article number | 103704 |
Journal | Journal of Applied Physics |
Volume | 108 |
Issue number | 10 |
DOIs | |
State | Published - Nov 15 2010 |
ASJC Scopus subject areas
- Physics and Astronomy(all)