2024/06/21 by Dinusha Herath Mudiyanselage, Mudiyanselage, Dinusha Herath, Dawei Wang +7
Engineering · Physics and Astronomy · #Acoustic Wave Resonator Technologies #Applied Physics (physics.app-ph) #FOS: Physical sciences #GaN-based semiconductor devices and materials #Metal and Thin Film Mechanics
paper · pdf · doi:10.48550/arxiv.2406.15688
openalex publication_date 2024/06/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
This letter reports the demonstration of lateral AlN Schottky barrier diodes (SBDs) on single-crystal AlN substrates by metalorganic chemical vapor deposition (MOCVD) with an ultra-low ideality factor (η) of 1.65, a breakdown voltage (BV) of 640 V, and a record high normalized BV by the anode-to-cathode distance (LAC). The homoepitaxially grown AlN epilayers had much lower defect densities and excellent surface morphology, and the AlN ohmic contacts also showed improvements. At forward bias, the devices exhibited ultra-low η of 1.65 and high Schottky barrier height of 1.94 eV. The device current was dominated by thermionic emission, while most previously reported AlN SBDs suffered from defect-induced current with much higher η of >4. Additionally, the devices also had excellent rectifying characteristics with ON/OFF ratios on the order of 107 to 109 and excellent thermal stability from 298 to 573 K. At reverse bias, the devices showed a high BV of 640 V and record-high normalized breakdown voltage (BV/LAC) in lateral AlN SBDs. This work represents a big step towards high-performance ultra-wide bandgap AlN-based high-voltage and high-power devices.