Patent ID: 6156621
Filing Date: 2000-12-05
Classification: H01L,Y10S

Abstract:
A method for fabricating direct wafer bond Si/SiO.sub.2 /Si substrates, which comprises:providing silicon wafers including a first silicon wafer serving as a carrier wafer and a second silicon wafer serving as a device wafer, the first silicon wafer and the second silicon wafer each having a front side and a rear side;etching trenches into the front side of the second silicon wafer;covering the trenches and the front side of the second silicon wafer with an insulation layer;subsequently forming a polysilicon layer by filling the trenches with polysilicon and covering the insulation layer on the front side of the second silicon wafer with the polysilicon;placing the front side of the second silicon wafer onto the front side of the first silicon wafer for forming joined silicon wafers with the front side of the first silicon wafer in direct contact with the polysilicon;heat-treating the joined silicon wafers; andthinning back the rear side of the second silicon wafer.