Active solid-state devices (e.g. – transistors – solid-state diode – Bulk effect device – Bulk effect switching in amorphous material
Reexamination Certificate
2005-04-06
2009-02-10
Loke, Steven (Department: 2818)
Active solid-state devices (e.g., transistors, solid-state diode
Bulk effect device
Bulk effect switching in amorphous material
C257S003000, C257S004000
Reexamination Certificate
active
07488967
ABSTRACT:
Disclosed are a phase change memory cell and a method of forming the memory cell. The memory cell comprises a main body of phase change material connected directly to a bottom contact and via a narrow channel of phase change material to a top contact. The channel is tapered from the top contact towards the main body. A minimum width of the channel has a less than minimum lithographic dimension and is narrower than a width of the main body. Therefore, the channel provides a confined region for the switching current path and restricts phase changing to within the channel. In addition an embodiment of the memory cell isolates the main body of phase change material by providing a space between the phase change material and the cell walls. The space allows the phase change material to expand and contract and also limits heat dissipation.
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Burr Geoffrey W.
Lam Chung Hon
Raoux Simone
Rossnagel Stephen M.
Schrott Alejandro G.
Gibb I.P. Law Firm LLC
International Business Machines - Corporation
Loke Steven
Nguyen Thinh T
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