05229647 is referenced by 404 patents and cites 8 patents.

A solid-state memory unit is constructed using stacked wafers containing a large number of memory units in each wafer. Vertical connections between wafers are created using bumps at the contact points and metal in through-holes aligned with the bumps. The bumps on one wafer make contact with metal pads on a mating wafer. Mechanical bonding between the bumps and mating metal pads on another wafer is preferably avoided so that fractures due to thermal expansion differentials will be prevented. Serial addressing and data access is employed for the memory units to minimize the number of connections needed. Also, the metal pads, through-holes and bumps are formed at corners of the die and thus shared with adjacent units whenever possible, further reducing the number of vertical connections.

Title
High density data storage using stacked wafers
Application Number
675795
Publication Number
5229647
Application Date
September 21, 1992
Publication Date
July 20, 1993
Inventor
Alfred P Gnadinger
Colorado Springs
CO, US
Agent
Arnold White & Durkee
Assignee
Micron Technology
ID, US
IPC
H01L 23/16
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