Wafer to wafer high density interconnects

Abstract

An integrated circuit package provides a high bandwidth interconnect between wafers using a very high density interconnect using a silicon bridge or a multi-layer flex between wafers. In some embodiments, more than one wafer may be mounted and connected with a rigid silicon bridge onto a common substrate. This common substrate can be matched, with respect to their coefficients of thermal expansion (CTE), to the silicon wafer. The CTE matched substrate can reduce the thermal mechanical stress on the wafers and the rigid silicon bridge interconnect. In some embodiments, a thinned silicon bridge is utilized to interconnect wafers which are mounted on separate glass substrates. The thinned bridge would allow for mechanical compliance between the wafers. In some embodiments, the wafers can be mounted onto separate glass substrates and attached with a fine pitch multi-layer flex structure which provides compliance between the wafers.