Jm. Myoung et al., Growth kinetics of GaN and effects of flux ratio on the properties of GaN films grown by plasma-assisted molecular beam epitaxy, J VAC SCI A, 17(5), 1999, pp. 3019-3028
The kinetic processes of GaN growth using plasma-assisted molecular beam ep
itaxy (PAMBE) have been investigated employing a precursor-mediated model.
Using the highly efficient radio-frequency (rf) plasma source which produce
s sufficient atomic nitrogen with a low density of ions having low kinetic
energy, significant ion-induced desorption is not observed, and the growth
kinetics are determined by the flux ratio between Ga and N, J(Ga)/J(N) It i
s found that the growth rates obtained by the precursor-mediated model fit
well with the experimental results, implying that the growth kinetics are e
ffective in describing the film growth by PAMBE. Also, it is found that the
flux ratio J(Ga)/J(N) is one of the most important factors which determine
the growth mode, degree of crystallinity, and electrical and optical prope
rties of GaN films. Although the growth rate is high (similar to 680 nm/h),
the surface morphology and crystalline quality of the films grown at a hig
her Ga flux are found to be significantly improved due to the two-dimension
al layer-by-layer growth mode [root-mean-square (rms) roughness approximate
to 1 nm]. Their electrical and optical properties are also discussed. (C)
1999 American Vacuum Society. [S0734-2101(99)09005-3].