A eutectic metal layer (e.g., gold/tin) bonds a carrier wafer structure to a device wafer structure. In one example, the device wafer structure includes a silicon substrate upon which an epitaxial LED structure is disposed. A layer of silver is disposed on the epitaxial LED structure. The carrier wafer structure includes a conductive silicon substrate covered with an adhesion layer. A layer of non-reactive barrier metal (e.g., titanium) is provided between the silver layer and the eutectic metal to prevent metal from the eutectic layer (e.g., tin) from diffusing into the silver during wafer bonding. During wafer bonding, the wafer structures are pressed together and maintained at more than 280° C. for more than one minute. Use of the non-reactive barrier metal layer allows the total amount of expensive platinum used in the manufacture of a vertical blue LED manufactured on silicon to be reduced, thereby reducing LED manufacturing cost.