Method of thinning semiconductor wafer of smaller diameter than thinning equipment was designed for

摘要

A method of thinning a product wafer using equipment designed for a wafer diameter, where the diameter of the product wafer is smaller than the wafer diameter of the thinning equipment by cutting an opening in a template wafer, where the template wafer is of a diameter that may be thinned by the thinning equipment, and where the opening accommodates the product wafer; affixing the template wafer to a holding material; affixing the product wafer to the holding material and inside of the template wafer with the integrated circuit side up; depositing an etch stop onto a handle wafer, where the handle wafer is at least as large as the template wafer; bonding adhesively the product wafer to the etch stop; removing the holding material; filling any gaps between the product wafer and the template wafer; using wax to make the product wafer sufficiently planar; thinning the product wafer using the thinning equipment; removing any excess wax; bonding adhesively the product wafer to a transfer wafer, where the transfer wafer is at least as large as the template wafer; removing the handle wafer; removing the etch stop; and removing any adhesive that remains on the product wafer.