Chemical vapour transport of III-V semiconductor materials

Over the temperature range 770 to 1310 K, however, two bromides compete for prominence, dependent upon temperature. In both instances, it is shown that vapour transport becomes rate limited at low temperature. Further to the chemical vapour transport of indium phosphide, the dissociative sublimation of the compound has also been investigated. Raman spectroscopy has been used to identify high temperature molecular species involved in vapour transport of III-V semiconductor materials. Supplementary work has been performed on the thermochemistry of indium monobromide. The heat of formation of indium bromide crystals has been determined using a solution calormetric technique. Differential scanning calorimetry was used to measure the heat capacity and heat of fusion, of the salt. An entrainment study of the evaporation of liquid indium monobromide was undertaken to yield a value for its heat of vaporisation. Using a statistical thermodynamic approach, the heat capacity of the vapour was calculated. Collating the information, a value for the heat of formation of indium monobromide gas at 1000 K has been calculated for use in other thermodynamic calculations.