A newly
developed unique combination of direct microscopic and
calorimetric measurements was used to study the crystal growth in
amorphous selenium (a-Se) thin films (500 nm) deposited on Kapton
tape and aluminum foil. The crystal growth rates (u
r) microscopically determined in the 65–110 °C
temperature range were similar to those for bulk selenium glass. The
crystal growth kinetics was described in terms of the screw dislocation
model with implemented temperature dependences of the growth activation
energy E
G and Ediger’s decoupling
parameter ξ. Extensive analysis of the literature data on the
crystal growth rates in thin selenium films revealed the dominant
effect of the number and distribution of the dangling bonds of the
[Se]
n
chains adjacent to the film/substrate
interface. The seemingly scattered u
r – T literature data were found to be consistent when the influences
of impurities, substrate quality, illumination, and deposition conditions
were accounted for. The macroscopic manifestation of the crystal growth
in selenium thin films was observed by means of differential scanning
calorimetry (DSC)the corresponding activation energies were
similar to the E
G values determined by
optical microscopy; the Avrami equation with the implemented u
r – T dependence was
able to accurately describe the macroscopic DSC data. Additional DSC
measurements for the selenium thin film scraped off the white glass
substrate have shown that the above-T
g annealing of such a material suppresses the crystallization, which
can be interpreted as the evidence of the dominant growth from the
mechanically activated crystallization centers.