a singulation process that uses wet etching thereby avoiding the mechanical and other stresses which may accompany other singulation processes such as die sawing or laser dicing the etching can be performed from either side of the devices the singulation methods described in the prior art include mechanical dicing sawing laser dicing or a combination of both the singulation process of the present invention is a cost effective method in which wet etching is used to remove materials based on the etch selectivity of the constituents of the substrate for example where ni is used to form the layer 106 it may be used as an etch stop since the wet etching can be designed to preferentially etch away copper 109 without significantly affecting the ni layer 106 furthermore the absence of the mechanical stresses or smearing that are typically encountered with mechanical dicing processes and the absence of the heat affected zone that is typical of laser dicing processes provides significant advantages over these two methods the method of the present invention is adapted to a particular type of substrate that is designed to withstand the chemical etching process similarly the properties of the etchant are tailored to match the materials of the substrate in one embodiment of the present invention the material removed by the chemical etching process is cu or ni and the etch barrier that protects the individual dies is au ni or sn in another embodiment of the present invention the structure formed below the epi layers the composite mirror plus the supporting carrier is encapsulated with a material that has a high etch selectivity with respect to the etchant that is used to remove the material that is connecting the different dies after.