Patent ID: 6884645

Claim:
A method for preparing a device structure, including a wafer structure having a wafer transverse coefficient of thermal expansion measured parallel to a transverse direction, comprising the steps of preparing a composite substrate structure having a deposition surface and comprising at least two substrate layers bonded together, wherein the composite substrate structure has an odd number of substrate layers, wherein the composite substrate structure has a substrate transverse coefficient of thermal expansion measured parallel to the transverse direction, wherein the substrate layers comprise at least two different substrate materials including a first substrate layer made of a first substrate material having a first-substrate-layer material transverse coefficient of thermal expansion, measured parallel to the transverse direction, greater than the wafer transverse coefficient of thermal expansion, and a second substrate layer made of a second substrate material having a second substrate-layer material transverse coefficient of thermal expansion, measured parallel to the transverse direction, less than the wafer transverse coefficient of thermal expansion, and wherein the substrate layers are present in relative proportions such that the substrate transverse coefficient of thermal expansion differs from the wafer transverse coefficient of thermal expansion by not more than about 2×10 −6 /° F.; and thereafter depositing the wafer structure onto the deposition surface of the composite substrate structure, wherein the transverse direction lies in the deposition surface.