Suppression of surface-originated gate lag by a dual-channel AlN/GaN high electron mobility transistor architecture
Abstract
A dual-channel AlN/GaN high electron mobility transistor (HEMT) architecture is demonstrated that leverages ultra-thin epitaxial layers to suppress surface-related gate lag. Two high-density two-dimensional electron gas (2DEG) channels are utilized in an AlN/GaN/AlN/GaN heterostructure wherein the top 2DEG serves as a quasi-equipotential that screens potential fluctuations resulting from distributed surface and interface states. The bottom channel serves as the transistor's modulated channel. Dual-channel AlN/GaN heterostructures were grown by molecular beam epitaxy on free-standing hydride vapor phase epitaxy GaN substrates. HEMTs fabricated with 300 nm long recessed gates demonstrated a gate lag ratio (GLR) of 0.88 with no degradation in drain current after bias stressed in subthreshold. These structures additionally achieved small signal metrics ft/fmax of 27/46 GHz. These performance results are contrasted with the non-recessed gate dual-channel HEMT with a GLR of 0.74 and 82 mA/mm current collapse with ft/fmax of 48/60 GHz.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 08, 2016
- Source ID
- 10.1063/1.4961009
Entities
People
- D. Scott Katzer
- David A. Deen
- David F. Storm
- David J. Meyer
- R. Bass
Organizations
- Office of Naval Research Global
- United States Naval Research Laboratory