Three-dimensionally integrated structure and method for fabricating same

Abstract

A 3D integrated structure and a method for fabricating the structure. In the method, a first trimming process is performed in a peripheral region of a wafer stack to form a chamfered surface adjacent to and surrounding an active device region. As a result, a thickness of the wafer stack along the chamfered surface gradually decreases from an edge of the active device region outward. In this way, a photoresist layer can be subsequently easily applied to cover the junction of the active device region and the chamfered surface, without the formation of discontinuities there, which may affect the subsequent processes. Additionally, in the method, a second trimming process is performed at an edge of the peripheral region to form a clamping surface adjacent to and surrounding the chamfered surface. In this way, it is unnecessary to clamp the wafer stack at a top surface thereof.

Dependencies are inferred from the claim text.