Temperature distribution and transport mode in a close-spaced vapor transport reactor for CuInSe₂ depositions

The present work is an improvement of a close-spaced vapor transport method to deposit CuInSe₂ thin films in a closed vertical reactor. The study concerns two points: (i) the determination of the actual source (T_s) and substrate (T_d) temperatures from experimental values measured in accessible points. For that, the equivalent thermal circuit of the reactor was established, and the equations were written to deduce T_s and T_d. (ii) The determination of the process governing the mass transfer, from experimental values of the deposition rate measured as a function of T_s and T_d. In our experimental conditions, the transport is limited by the reaction kinetics, not by the diffusion. © 1998 American Institute of Physics.