Effect of growth conditions on the conductivity of Mg doped p-type GaN by Molecular Beam Epitaxy

✍ Scribed by Simon, John ;Jena, Debdeep

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 439 KB
• Volume: 205
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200778745

✦ Synopsis

Abstract

The performance of III–V nitride heterostructure bipolar transistors has been limited by highly resistive p‐type layers, in addition to difficulties associated with a precise p–n junction placement at the emitter‐base heterojunction due to the Mg‐memory effect during growth by Metal‐Organic Chemical Vapor Deposition. The problem of precise p–n heterojunction placement can be solved by Molecular Beam Epitaxy growth. To investigate this possibility, in this work, we present a comprehensive study of the effect of III/V ratio, growth temperature, and Mg doping on the resistivity of Mg doped GaN layers grown by Molecular Beam Epitaxy. N~2~‐rich growth conditions are found to lead to a temperature‐ independent low hole mobility, as opposed to Ga‐rich growth conditions that lead to higher hole mobilities that vary with temperature. In addition, the growth temperature, Ga flux, and Mg flux windows leading to the highest p‐type conductivity are identified. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)