Micro-electrical-mechanical (MEMS) wafers in which a lens is formed on a micro-electrical-mechanical structure. The micro-electrical-mechanical wafers can comprise a substrate, MEMS structures, and a lens array. A method of forming a micro-electrical-mechanical wafer comprises providing a substrate, forming a micro-electrical-mechanical structure on the substrate, forming a carrier, forming a lens array on the carrier, and transferring the lens array from the carrier onto the micro-electrical-mechanical structure. The lens array is placed above the micro-electrical-mechanical structure.