Patent ID: 7816233

Claim:
A method of manufacturing a composite wafer structure, comprising the steps of: (a) preparing a device wafer having a first circumference, a bond surface and a bottom surface; (b) forming a groove on the bond surface along the first circumference of the device wafer, wherein a margin exists between the groove and the first circumference of the device wafer; (c) preparing a base wafer having a top surface; (d) bonding the bond surface of the device wafer onto the top surface of the base wafer; and (e) grinding and polishing the bottom surface of the device wafer until an initial thickness of the device wafer is reduced into an expected thickness to complete the composite wafer structure; wherein during the grinding and polishing of the bottom surface of the device wafer, the margin is fractured by cracks induced at a tip of the groove and then removed; wherein the base wafer has a second circumference, after step (d), in which a maximum radial distance on the bond surface of the device not bonded with the top surface of the base wafer is defined as a mismatch gap, and a thickness of the margin is equal to or larger than the mismatch gap; wherein the second circumference of the base wafer is ground or laser cut until a diameter of the base wafer is reduced to be equal to that of the device wafer; and wherein the device wafer and the base wafer are respectively formed of a semiconductor material of a first type and a second type.