Multitarget system for growth of thin films by pulsed laser deposition

Abstract

In this work we present the design, construction and the evaluation of a system to growth multiple layers of thin films using the pulsed laser deposition (PLD). The system is equipped with a mechanism of multiple targets and substrates. It has two revolving plates that can be manipulated from outside the chamber. The first serves to interchange four targets without breaking the vacuum or altering the internal conditions of the chamber. It also allows to put to the target in rotation around it's own axis. This rotation gives uniformity to the wearing down of the target thus enhancing the uniformity of the growing film. The second plate allows to change the substrate without opening the vacuum chamber. This second plate has three substrate holders. The system has a substrate heather that works at a maximum temperature of~$600^\circ$C. Both mechanisms are mounted in individual standard 6 inches ConFlat flanges and can be used in cameras of high or ultrahigh vacuum. The working chamber is evacuated by a standard oil diffusion pumping system. A Nd:YAG (Neodymium Yttrium Aluminum Garnet) infrared laser at wavelength of 1064 nm and about $25 $Wcm$^{2}$/pulse is used to vaporize the target. The capability of the system is evaluated by growing several basic structures of super-stratum CdTe-CdS used for solar cell on conductive glass (TCO): TCO/CdS, TCO/CdTe and TCO/CdS/CdTe and characterizing them by grazing incidence X-ray diffraction (GIXRD).