| About this Abstract |
| Meeting |
Materials Science & Technology 2009
|
| Symposium
|
Characterization and Modeling of Ceramic-Ceramic and Metal-Ceramic Interfaces
|
| Presentation Title |
First Principles Study of GaN-GaN Junctions with Ultrathin AlN Interlayers |
| Author(s) |
Rohan Mishra, Oscar Restrepo, Siddharth Rajan, Wolfgang Windl |
| On-Site Speaker (Planned) |
Rohan Mishra |
| Abstract Scope |
GaN-GaN junctions with ultrathin AlN interlayers are being looked upon as candidates for high-frequency, high-power transistors and light emitting devices that can be operated in the deep UV region. As these heterostructure based devices are shrinking to a few monolayers in thickness, it has become imperative to study their properties at such a small scale. We report an <I>ab-initio</I> density functional theory study of the effect of surface charges on the band behavior and polarization in these heterojunctions. The layer-projected density of states indicates that geometry optimization is necessary to get the correct band-bending. Interestingly the bulk polarization values that allow the formation of a two-dimensional electron gas at the interface are found to be valid to a few monolayers of AlN. At such small thicknesses, surfaces are found to have a strong impact on the energy bands such that the conduction band minima and valence band maxima overlap. |
| Proceedings Inclusion? |
Undecided |