Thin film coatings have become an intensively research area for applications related to solar, sensor technologies, and some of the optical applications. The deposition of metallic thin films is mainly carried through DC magnetron sputtering process. The deposition of metallic thin films mainly depends of the process parameters, such as RF power, DC power, and Argon gas flow rate. To obtain the effects of process parameters, L orthogonal array are used. 410- Solar Visible / NIR 9 Spectrophotometer are used to estimate solar absorptance, reflectance, and mirror assessment. These are typical test methods for the measuring solar absorptance, solar reflectance, and transmittance of materials. 410-Solar measures reflectance ta seven sub-bands in 300-2500 nm spectral regions. ET 100 emissometer measures directional reflectance at six bands in the thermal infrared spectral region at two incident angles 20o and 60o. Hence, Nano structured thin films are exhaustively used in the area of solar selective coatings.