Comparative Study on MOCVD Growth of a-Plane GaN Films on r-Plane Sapphire Substrates Using GaN, AlGaN, and AIN Buffer Layers
In: Journal of electronic materials, Jg. 38 (2009), Heft 9, S. 1938-1943
Online
academicJournal
- print, 20 ref
Zugriff:
In this work, we have comparatively investigated the effects of the GaN, AlGaN, and AIN low-temperature buffer layers (BL) on the crystal quality of a-plane GaN thin films grown on r-plane sapphire substrates. Scanning electron microscopy images of the a-plane GaN epilayers show that using an AlGaN BL can significantly reduce the density of surface pits. The full-width at half-maximum values of the (1120) x-ray rocking curve (XRC) are 0.19°, 0.36°, and 0.48° for the films grown using Al0.15Ga0.85N, GaN, and AIN BLs, respectively, indicating that an AlGaN BL can effectively reduce the mosaicity of the films. Room-temperature photoluminescence shows that the AlGaN BL results in lower impurity incorporation in the subsequent a-plane GaN films, as compared with the case of GaN and AlN BLs. The higher crystal quality of a-plane GaN films produced by the Al0.15Ga0.85N BL could be due to improvement of BL quality by reducing the lattice mismatch between the BL and r-sapphire substrates, while still keeping the lattice mismatch between the BL and epitaxial a-plane GaN films relatively small.
Titel: |
Comparative Study on MOCVD Growth of a-Plane GaN Films on r-Plane Sapphire Substrates Using GaN, AlGaN, and AIN Buffer Layers
|
---|---|
Autor/in / Beteiligte Person: | DAI, J. N ; WU, Z. H ; CHEN, C. Q ; YU, C. H ; ZHANG, Q ; SUN, Y. Q ; XIONG, Y. K ; HAN, X. Y ; TONG, L. Z ; HE, Q. H ; PONCE, F. A |
Link: | |
Zeitschrift: | Journal of electronic materials, Jg. 38 (2009), Heft 9, S. 1938-1943 |
Veröffentlichung: | Heidelberg: Springer, 2009 |
Medientyp: | academicJournal |
Umfang: | print, 20 ref |
ISSN: | 0361-5235 (print) |
Schlagwort: |
|
Sonstiges: |
|