We present details of the deposition of transparent and earth-abundant p-type CuBr films with high hole conductivity and the fabrication and characterization of a prototype solar cell based on p-CuBr/n-Si heterojunctions. p-type CuBr films with typical resistivities and hole concentrations of 7 x 10(-1) Omega cm and 7.5 x 10(19) cm(-3), respectively, are deposited by thermal evaporation followed by oxygen plasma treatment. The transparent p-type films show strong room temperature photoluminescence at similar to 2.97 eV. The current voltage (I-V) characteristics of the heterojunctions show good diode behaviour. Power conversion efficiency of similar to 2% was achieved for the heterojunction device without any optimization of the cell structure under AM 1.5 illumination condition with a short circuit current (J(SC)) and open circuit voltage (V-oc) of 13.2 mA/cm(2) and 0.44 V, respectively.