Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 83: Focus Session: III-Nitride Heterostructures for Optoelectronics - Polarization Reduction, Green Gap and High In-containing Alloys

HL 83.4: Hauptvortrag

Donnerstag, 29. März 2012, 16:45–17:15, EW 201

Low Temperature Growth Methods for Overcoming Perceived Limitations in III-Nitride Epitaxy — •W. Alan Doolittle, Michael Moseley, and Brendan Gunning — Georgia Institute of Technology, Atlanta GA, USA

Historically, III-Nitride epitaxy has been performed at relatively high temperatures leading to excellent material quality in the wide bandgap regime. However, this mindset when applied to the moderate to low bandgap alloys, has resulted in serious issues with phase separation, loss of uniformity and limitations in the ability to p-dope materials. Herein, a new approach centered around substantially colder epitaxy is described and is shown to result in non-phase separated InGaN grown throughout the immiscibility gap and p-type GaN and InGaN with hole concentrations well above the previously perceived limits. High structural and electronic quality is maintained even at significantly lower temperatures using extremely metal rich growth conditions. Structural, electronic and optical properties are presented and the compromises versus benefits low temperature epitaxy imposes are discussed.