Back reflector arrays are applied to the surface distal to the incident light receiving surface of a thin film solar cell to increase its efficiency by altering the reflected light path and thereby increasing the path length of light through the active layer of the solar cell. The back reflector is an array of features of micrometer proportions. The feature may be concave or convex features such as hemispheres, hemi-ellipsoids, partial-spheres, partial-ellipsoids, or combinations thereof The feature may be pyramidal. A method of forming the back reflector array is by forming an array of features from a photocurable resin, subsequent curing the resin and metalizing the cured resin to render the surface reflective. The photocurable resin can be applied by inkjet printing or rolling or stamping with a mold.
 The subject invention was made with partial government support under the National Science Foundation, Grant No. ECCS-0644690, and U.S. Department of Energy Solar Energy Technologies Program, Grant No. DE-FG36-08G018020. The government has certain rights to this invention.