Raytheon Company

Andrew Cahill

Daniel D Lofgreen

Sean P Kilcoyne

Jonathan Getty

Paul A Drake

Scott S Miller

Christine Frandsen

Shannon F Wilkey

Sean F Harris

Disclosed is a process for manufacturing individual die devices, with a desired or predicted amount of flatness, from a bonded wafer process. The flatness of a bonded wafer is measured at point in the wafer manufacturing process. This measurement is compared to a value predetermined by an empirical analysis of previous devices made by the same process. If the flatness of the bonded wafer is not at the predetermined value, then one or more compensation layers are provided to the bonded wafer to obtain the predetermined flatness value. Once obtained, subsequent processing is performed and the resulting individual dies are obtained with the desired flatness characteristic.

Stress compensation and relief in bonded wafers

In one aspect, a method includes heating a wafer chuck, heating a first wafer, depositing a first epoxy along at least a portion of a surface of the first wafer disposed on the wafer chuck, spinning the wafer chuck to spread the first epoxy at least partially across the first wafer, placing a second wafer on the first epoxy disposed on the first wafer and bonding the second wafer to the first epoxy under vacuum to form a two-wafer-bonded structure.

Wafer stacking to form a multi-wafer-bonded structure

Methods and apparatus for enhancing the flatness of a die by applying adhesive to a shim having a selected flatness, rotating the shim to spread the adhesive to a layer having a uniform thickness, evacuating a chamber to create a vacuum; manipulating a die onto the adhesive layer in the chamber; and reducing a level of the vacuum to pressure the die onto the adhesive layer such that the bow in the die is reduced as the die conforms to the shim.

Enhancing die flatness

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Goleta, CA, United States of America

Andrew Cahill