The effects of the layer thickness and of Si doping on the dislocation type and density, electron concentration, and deep trap spectra were studied for epitaxially laterally overgrown (ELOG) GaN films with the ELOG region thickness varying from 6 to 12 μm. Electron beam induced current imaging shows that for the thickest layers, the major part of the threading dislocations are filtered out while for thinner films they bend, but do not go out of play. The concentration of residual donors and major electron traps is found to decrease with increasing the film thickness. Si doping suppresses the concentration of the main electron trap with activation energy of 0.6 eV and enhances the concentration of the main hole trap at Ev +0.85 eV.
|Number of pages
|Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures
|Published - 2008
Bibliographical noteFunding Information:
The work at IRM was supported in part by a grant from Russian Foundation for Basic Research (RFBR Grant No. 05-02-08015) and ICTS (Grant No. 3029). The work at UF is partially supported by NSF DMR-070010.
ASJC Scopus subject areas
- Condensed Matter Physics
- Electrical and Electronic Engineering