XeF2 etching of epitaxial Nb2N for lift-off or micromachining of III-N materials and devices
Abstract
This paper presents characterization of the effects of XeF2 vapor phase etching conditions on the lateral etch rate and etch uniformity of a sacrificial, epitaxial Nb2N layer grown between a III-N high-electron-mobility transistor heterostructure and a 6H-SiC substrate. To achieve uniform and repeatable lateral Nb2N removal, an etch temperature of 100 °C or higher was required, providing average etch rates ranging from 10 to 40 μm/min. A net compressive stress and positive strain gradient in the released III-N material were inferred from the buckling of clamped-clamped beams and the convex curvature of cantilever structures, respectively. XeF2 etching of epitaxial Nb2N sacrificial layers in III-N material structures allows for a highly selective, completely dry release process that is compatible with common micromachining and epitaxial lift-off techniques.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 19, 2017
- Source ID
- 10.1116/1.4994400
Entities
People
- Brian P. Downey
- D. Scott Katzer
- David J. Meyer
- Matthew T. Hardy
- Neeraj Nepal
Organizations
- Defense Advanced Research Projects Agency
- United States Naval Research Laboratory