2.2. Deposition of CdTe films
CdTe films were deposited by CSS method on boro-aluminosilicate glass substrates (corning 1737, DELTA Technologies, 25mm×25mm×1.1 mm). The reaction chamber inside a quartz glass reactor consisted of the CdTe source and a substrate separated by a quartz glass ring as spacer ( Fig. 1). These were covered by two graphite plates and heat treatment was achieved by infrared radiation from lamps outside the reactor. Two thermocouples, one each for the source and for the substrate, were used to monitor the graphite block temperatures. Independent regulation of source and substrate temperature was carried out by Eurotherm 91e controllers. The pressure inside the reactor was controlled by a gas inlet and a vacuum connection.