Jh. Coombs et al., LASER-INDUCED CRYSTALLIZATION PHENOMENA IN GETE-BASED ALLOYS .2. COMPOSITION DEPENDENCE OF NUCLEATION AND GROWTH, Journal of applied physics, 78(8), 1995, pp. 4918-4928
The laser-induced crystallization behavior of GeTe-based amorphous all
oys has been measured with a novel multipulse laser technique. This en
ables the composition dependence of the nucleation rate and crystal gr
owth speed to be independently followed. Two types of crystallization
are investigated. The first involves single-phase crystallization of q
uaternary alloys based on Ge39Sb9Te52, in which the composition depend
ence of nucleation and growth is followed as Se, S, Sn, and Si are inc
luded. Both the nucleation rate and crystal-growth speed vary exponent
ially with the composition, and a correlation is found between crystal
lization behavior and bond strengths. The second involves multiphase c
rystallization in the GeSbTe ternary system. It is shown that the obse
rved variations in crystallization behavior primarily arise from the c
omposition dependence of nucleation rather than crystal growth. The im
plications of this finding for the importance of long range diffusion
during crystallization in the GeSbTe system are discussed. (C) 1995 Am
erican Institute of Physics.