Jpn. J. Appl. Phys. 43 (2004) pp. L1537-L1539  |Previous Article| |Next Article|  |Table of Contents|
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Letter

GaN Crystal Growth on Sapphire Substrate Using Islandlike GaN Buffer Formed by Repetition of Thin-Layer Low-Temperature Deposition and Annealing in rf-Plasma Molecular Beam Epitaxy

Mitsuaki Shimizu, Yoshitaka Hirata¹, Guanxi Piao and Hajime Okumura

(Received June 28, 2004; revised October 4, 2004; accepted October 16, 2004; published November 12, 2004)

We employed a new buffer growth method of superposing the thin low-temperature (LT)-grown GaN layers using an rf-plasma molecular beam epitaxy (MBE) system. The islandlike buffer structure was formed by the repetition of the thin LT GaN layer deposition and annealing process. From the measurement of the surface morphology at the initial stage of the growth on this buffer structure, it is found that the coalescence in the initial growth stage occurred mainly between islands on the same step surface of the substrate. The surface morphology of the grown GaN layer had a flat steplike feature. The X-ray diffraction (XRD) analysis of a 2.5-µm-thick GaN layer grown on this buffer structure showed a 210 arcsec full width half maximum (FWHM) of the peak in the (0002) ω-rocking curve, and 850 arcsec FWHM in the (10–12) ω-rocking curve.

KEYWORDS: GaN, MBE, low-temperature buffer, rf-plasma, islandlike buffer
URL: http://jjap.ipap.jp/link?JJAP/43/L1537/
DOI: 10.1143/JJAP.43.L1537

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