Impact of oxygen precursor flow on the forward bias behavior of MOCVD-Al2O3 dielectrics grown on GaN
Abstract
This paper investigates the effects of the oxygen precursor flow supplied during metalorganic chemical vapor deposition (MOCVD) of Al2O3 films on the forward bias behavior of Al2O3/GaN metal-oxide-semiconductor capacitors. The low oxygen flow (100 sccm) delivered during the in situ growth of Al2O3 on GaN resulted in films that exhibited a stable capacitance under forward stress, a lower density of stress-generated negative fixed charges, and a higher dielectric breakdown strength compared to Al2O3 films grown under high oxygen flow (480 sccm). The low oxygen grown Al2O3 dielectrics exhibited lower gate current transients in stress/recovery measurements, providing evidence of a reduced density of trap states near the GaN conduction band and an enhanced robustness under accumulated gate stress. This work reveals oxygen flow variance in MOCVD to be a strategy for controlling the dielectric properties and performance.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 06, 2017
- Source ID
- 10.1063/1.5009757
Entities
People
- Davide Bisi
- Maher Tahhan
- Matteo Meneghini
- Ramya Yeluri
- S. Keller
- Silvia H Chan
- Steven P. DenBaars
- Umesh Mishra
- Xiang Liu
Organizations
- ARPA-E
- Office of Naval Research
- United States Department of Energy
- University of Padua