Vapor transport deposition of cadmium telluride films

Polycrystalline CdTe thin films are grown by vapor transport deposition onto moving substrates using a linear cross-web source for operation at low vacuum and high growth temperature. The source design, based on delivery of a carrier gas saturated with Cd and Te₂ vapors, overcomes the limitations of other vapor deposition methods. Models for vapor transport deposition and radiative transfer within the source facilitate a quantitative understanding of source behavior leading to control of film deposition. The deposition has been characterized over a wide range of operating parameters. Dense, single phase device quality CdTe films have been fabricated. Deposition of other compound semiconductor materials has also been demonstrated.