Patent ID: 6143628
Filing Date: 2000-11-07
Classification: H01L

Abstract:
A method of manufacturing a semiconductor substrate comprising the steps of:preparing a first substrate having a porous region including at least two layers different in porosity and a non-porous layer formed on said porous region;bonding a surface of said non-porous layer of said first substrate to a surface of a second substrate;separating said first and second substrates from each other to transfer said non-porous layer to said second substrate; andremoving the residual portion of the porous region remaining on a separation surface of said second substrate or making the residual portion non-porous to smooth said separation surface;wherein the step of preparing said first substrate comprises a step of forming a first porous layer of 1 .mu.m or less thickness, a second porous layer adjacent to said first porous layer and high in porosity, and said non-porous layer adjacent to said first porous layer.