The effect of nitrogen ambient pressure on growth of AlN films has been exa
mined. High-quality epitaxial AlN films were grown on (0001) sapphire subst
rates using pulsed laser deposition from a sintered AlN target in low nitro
gen ambient of 9.0 x 10(-5) Torr. The orientation of AlN films can be contr
olled by nitrogen pressure. AlN films are c-axis oriented when grown in a n
itrogen pressure of 9.0 x 10(-5) to 4.0 x 10(-2) Torr. Film orientation con
verted to a-axis as nitrogen pressure increased to 4.0 x 10(-1) Torr. The X
-ray rocking curves of the AlN (0002) peak became narrower with decreasing
ambient pressure and yielded a full width at half-maximum of 0.078 degrees.
The N/Al composition ratio increases with nitrogen pressure. (C) 2000 Else
vier Science S.A. All rights reserved.