P. Sevvanthi, A. Claude*, C. Jayanthi and A. Poiyamozhi
Spin coating is an easy and efficient technique to grow good quality thin film crystals and amorphous films suitable for many applications in science in technology namely sensors, filters and solar cells. The engineering and design for the spin coating apparatus was conceived tested and fabricated indigenously in-house inside the laboratory to grow thin film crystals and amorphous films to suit various applications. The rotor consists of an AC motor capable of reaching speeds like 1200 rpm, 2400 rpm and 3600 rpm. A rectangular substrate holder is fabricated on the top of the stub firmly fixed so that not to spin off while reaching the above said high speeds. A transparent lid is fixed with a provision for applying the liquefied charge periodically as droplets onto the substrate. A spill container cum arrestor is fabricated around the spinning platform in order to reduce the splashing and wasting of the charge. The charge is taken in the form of the solution with an optimal texture and super saturation so that the long range order is maintained else there is scope of accumulation and multiple nucleation which will prevent the film from a smooth formation. Homogeneous and Heterogeneous combinations of single layered and multiple layered thin films are realised after effecting a coating with an optimal spin speed. The thin films realised after the process will be subjected to structural, functional and optical characterizations.
