This is our book on the Design of Automated JNSP System for Thin Film Device Applications. During my research, I was able to feel that enough work has already been done on the fabrication and characterization of thin films, but lesser research has been reported on improving the quality of thin films and the parameters necessary to isolate good quality thin films. So, we designed an automated jet nebulizer spray pyrolysis (JNSP) system and isolated certain parameters that are responsible for the better quality of thin films, and standardize the process for thin film deposition using automation. Zinc (Zn) doped copper oxide (CuO) thin films were deposited by manual and automated JNSP system and their characterization was compared for p-n junction diode application. To the best of our knowledge, the fabrication of p-Zn: CuO/n-Si diode using an automated JNSP system has been not much studied in the available literature except for a few. To a large extent, we are successful in this research which is presented in this book.