Electrical Comparison of and Gate Dielectrics on GaN

• Published in: IEEE transactions on electron devices Vol. 60; no. 12; pp. 4119 - 4124
• Main Authors: Bothe, Kyle M., von Hauff, Peter A., Afshar, Amir, Foroughi-Abari, Ali, Cadien, Kenneth C., Barlage, Douglas W.
• Format: Journal Article
• Language: English
• Published: IEEE 01-12-2013
• Subjects: Atomic layer deposition (ALD); Capacitance; Dielectric measurement; Dielectrics; Gallium nitride; GaN MOS; Hafnium compounds; high- kappa dielectric; interface traps; Logic gates; mobility; MOS capacitors (MOSCAP); Scattering
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2013.2283802

A low-temperature atomic layer deposition technique for high-κ dielectric films on GaN templates was investigated for MOS applications. This improved growth method produced capacitance densities and a field effect mobility approaching 375 cm 2 /Vs for ZrO 2 and 250 cm 2 /Vs for HfO 2 films on GaN. Furthermore, the low density of dielectric-semiconductor interface traps confirmed a reliable cohesion between the high-κ and GaN. The improved gate dielectric deposition technique has the capabilities to improve the overall quality of GaN-based MOSFETs.