Patent ID: 6858517

Claim:
A method for forming a heterogeneous assembly, which comprises: bonding a surface of a first substrate to a surface of a second substrate, wherein the first substrate includes a zone of weakness therein to define a transfer layer adjacent the first surface, and the first and second substrates made of first and second materials, respectively, with the first material having a different coefficient of thermal expansion than the second material; providing a stiffening substrate of a third material to maintain sufficient flatness and prevent breakage of the transfer layer during detachment from the first substrate, with the stiffening substrate being bonded to one of the first or second substrates and the third material having a coefficient of thermal expansion that is the same as or close to that of the material of the substrate to which the stiffening substrate is bonded; and detaching the transfer layer from the first substrate along the zone of weakness to form a heterogeneous assembly of the transfer layer and second substrate.