Thin films of CuGaSe₂ (CGS) were deposited on (100) n-Si by rf magnetron sputtering from a stoichiometric CuGaSe₂ target. Compositional analysis of films by energy dispersive X-ray spectroscopy (EDS) and Rutherford backscattering (RBS) analysis yielded a composition of Cu₁Ga₁Se₁ which indicates that the films were Se deficient. Transmission electron microscopy (TEM) of cross-sectional samples indicated that the films were polycrystalline. Metal contact studies indicated ohmic contacts with specific contact resistance, ρ_c of 9.12 x 10^-5 Ω.cm² for Pt and 7.9 x 10^-4 Ω.cm² for Au. Rectifying contacts yielded a built-in potential (V_bi), that varied between 1.56 and 2.33 V for Al contacts and 0.5 – 0.7 V for Ag contacts. Optical absorption study of the films indicated a bandgap of ~1.5 eV. Solar cells fabricated from the CGS/n-Si heterojunction produced an open circuit voltages (V_oc), of 187 mV, a short circuit current density (J_sc), of 0.47 mA/cm².