  Indium selenide compounds are promising materials for energy conversion,
spintronic applications, and chemical sensing. However, it is difficult to grow
stoichiometric indium selenide crystals due to the high equilibrium selenium
vapor pressure and the complicated phase equilibrium system of indium selenide
compounds. In this paper, we apply a novel and convenient crystal growth
method, in which the saturated solution is grown by the application of a
selenium vapor. In this method, selenium vapor at a pressure higher than the
saturated vapor pressure is applied to molten indium, such that the selenium
continuously dissolves into the indium solution until the solubility at the
growth temperature is reached; then a slow cooling process results in
crystallization. The selenium dose is matched to its solubility so that indium
selenide compounds can be selectively grown just by controlling the temperature
without the need to consider the chemical ratio in the solution. The pressure
of the vapor is controlled during the whole growth process so that any
deviation from a stoichiometric composition in the crystal can be controlled.
Both InSe and In2Se3 were successfully grown using this method, and we have
investigated the growth mechanism and found the growth window for each
compound. This study presents a novel and convenient approach to fabricating
transitional metal chalcogenides without deficiencies in the chalcogen element.

Materials Science;Applied Physics;Chemical Physics