The promising solar material Cadmium Telluride (CdTe) is successfully deposited on both plain glass and ITO coated glass substrates. Many variations in composition of the solution used for deposition of the film are made to optimize the deposition conditions. The bandgap calculated from optical transmission studies is found to be a function of the Cd/Te atomic ratio in the film. The atomic ratio in the film is a function of the Cd/Te concentration ratio in the solution used in deposition. Based on several experimental data points an equation involving the Cd/Te atomic ratio in the film and the chemistry of the solution is deduced.
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Source: First Solar, Inc.
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