Semiconductor wafer having a thin die and tethers and methods of making the same

Abstract

A semiconductor wafer ( ) that includes a support body ( ), at least one thin die ( ), and a plurality of tethers ( ). The support body ( ) is made of a semiconductor material. The thin die ( ) has a circuit ( ) formed thereon and has an outer perimeter ( ) defined by an open trench ( ). The open trench ( ) separates the thin die ( ) from the support body ( ). The tethers ( ) extend across the open trench ( ) and between the support body ( ) and the thin die ( ). A method of making a thin die ( ) on a wafer ( ) where the wafer ( ) has a support body ( ), a topside ( ) and a backside ( ). A circuit ( ) is formed on the topside ( ) of the wafer ( ). The method may include the steps of: forming a cavity ( ) on the backside ( ) of the wafer ( ) beneath the circuit ( ) that defines a first layer ( ) that includes the circuit ( ); forming a trench ( ) around the circuit ( ) on the topside ( ) of the wafer ( ) that defines an outer perimeter ( ) of the thin die ( ); forming a plurality of tethers ( ) that extend across the trench ( ) and between the wafer support body ( ) and the thin die ( ); and removing a portion of the first layer ( ) to define the bottom surface ( ) of the thin die ( ).