Abstract: A phase change memory device includes a memory cell, first word line conductor and a second word line conductor, and first and second access devices responsive to the first and second word line conductors respectively. Control circuits are arranged to access the memory cell for read operations using only the first word line conductor to establish a current path from the bit line through the memory cell to a source line through the first access device, and to access the memory cell for operations to reset the memory cell using both the first and second access devices to establish a current path from the bit line through the memory cell to two source lines.
Type:
Grant
Filed:
April 13, 2010
Date of Patent:
July 12, 2011
Assignees:
Macronix International Co., Ltd., International Business Machines Corporation
Abstract: A multi-level, phase change memory cell has first and second thermal isolation materials having different thermal conductivity properties situated in heat-conducting relation to first and second boundaries of the phase change material. Accordingly, when an electrical current is applied to raise the temperature of the memory material, heat is drawn away from the memory material asymmetrically along a line orthogonal to electric field lines between the electrodes.
Abstract: A memory cell includes a bottom electrode, a top electrode and a memory element switchable between electrical property states by the application of energy. The bottom element includes lower and upper parts. The upper part has a generally ring-shaped upper end surrounding a non-conductive central region. The lateral dimension of the lower part is longer, for example twice as long, than the lateral dimension of the ring-shaped upper end. The lower part is a non-perforated structure. The memory element is positioned between and in electrical contact with the top electrode and the ring-shaped upper end of the second part of the bottom electrode. In some examples the ring-shaped upper end has a wall thickness at the memory element of 2-10 nm. A manufacturing method is also discussed.
Abstract: A memory device has a sidewall insulating member with a sidewall insulating member length according to a first spacer layer thickness. A first electrode formed from a second spacer layer having a first electrode length according to a thickness of a second spacer layer and a second electrode formed from the second spacer layer having a second electrode length according to the thickness of the second spacer layer are formed on sidewalls of the sidewall insulating member. A bridge of memory material having a bridge width extends from a top surface of the first electrode to a top surface of the second electrode across a top surface of the sidewall insulating member, wherein the bridge comprises memory material.
Type:
Grant
Filed:
May 30, 2006
Date of Patent:
October 26, 2010
Assignee:
Macronix International Co., Ltd.
Inventors:
Erh Kun Lai, Chia Hua Ho, Kuang Yeu Hsieh
Abstract: A memory cell includes a memory cell layer over a memory cell access layer. The memory cell access layer comprises a bottom electrode. The memory cell layer comprises a dielectric layer and a side electrode at least partially defining a void with a memory element therein. The memory element comprises a memory material switchable between electrical property states by the application of energy. The memory element is in electrical contact with the side electrode and with the bottom electrode. In some examples the memory element has a pillar shape with a generally constant lateral dimension with the side electrode and the dielectric layer surrounding and in contact with first and second portions of the memory element.
Abstract: A method for forming an application specific integrated circuit, comprises receiving a circuit design for the application specific integrated circuit from a designer; performing an initial place and route layout of the circuit design which leaves a group of buffer modules unused, based upon a partially predesigned integrated circuit, in which the partially predesigned integrated circuit includes a plurality of logic modules and a plurality of buffer modules uniformly distributed amongst the logic modules; evaluating load and timing characteristics for the initial place and route layout of the circuit design; and integrating buffer modules from the group of unused buffer modules into the circuit design, based on the load and timing characteristics evaluated.
Type:
Grant
Filed:
June 11, 2003
Date of Patent:
October 11, 2005
Assignee:
Lightspeed Semiconductor Corporation
Inventors:
Dana How, Adi Srinivasan, Abbas El Gamal