Patent ID: 8481408

Claim:
A method for relaxing a layer of a strained material which comprises: depositing a first low-viscosity layer on a first face of a strained material layer; bonding a first substrate to the first low-viscosity layer to form a first composite structure; depositing a second low-viscosity layer on a stiffener that is arranged over a face of the strained layer but not bonded thereto; subjecting the composite structure to heat treatment sufficient to cause reflow of the first low-viscosity layer so as to at least partly relax the strained material layer; applying a first mechanical pressure to a second face of the strained material layer wherein the second face is opposite to the first face and with the mechanical pressure applied perpendicularly to the strained material layer during at least part of the heat treatment; and applying a second mechanical pressure in a direction that is opposite to that of the first mechanical pressure with the second mechanical pressure applied perpendicularly to the strained material layer during at least part of the heat treatment, wherein the mechanical pressure assists in the suppression of wrinkles in the strained material layer.