Patent ID: 6995034

Claim:
A method for forming a MEMS device, comprising: providing a first semiconductor wafer having electrodes thereon; providing a second transparent wafer; providing a sacrificial layer on the second wafer; forming a plurality of MEMS elements on the sacrificial layer wherein MEMS are deflectable elements; releasing the plurality of MEMS devices by etching away the sacrificial layer; mixing one or more spacer elements into an adhesive or providing one or more spacer elements separately from the adhesive for separating the wafers during and after aligning the first and second wafers and bonding; applying the adhesive to one or both of the first and second wafers; bonding the first and second wafers together with the spacer elements therebetween so that the first and second wafers are held together in a spaced apart relationship as a wafer assembly; wherein the aligning comprises aligning each deflectable element on the second wafer with at least one electrode on the first wafer singulating the wafer assembly into individual dies; and wherein a plurality of light blocking masks are formed on the second wafer; wherein when the wafer assembly is singulated into wafer assembly dies, a light blocking mask is disposed on a second wafer portion within each wafer assembly die.