IBM Assigned Six Patents

Phase change memory using multiple stacks of PCM materials
International Business Machines Corp., Armonk, NY, has been assigned a patent (11,380,843) developed by Shen, Tian, Clifton Park, NY, Wu, Heng, Guilderland, NY, Brew, Kevin W., and Zhang, Jingyun, Albany, NY, for a “phase change memory using multiple stacks of PCM materials.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A method is presented for improved linearity of a phase change memory (PCM) cell structure. The method includes forming a bottom electrode over a substrate, constructing a PCM stack including a plurality of PCM layers each having a different crystallization temperature over the bottom electrode, and forming a top electrode over the PCM stack. The crystallization temperature varies in an ascending order from the bottom electrode to the top electrode.”

The patent application was filed on February 13, 2020 (16/789,502).

Phase change memory cell with second conductive layer
International Business Machines Corp., Armonk, NY, has been assigned a patent (11,380,842) developed by Li, Juntao, Cohoes, NY, Cheng, Kangguo, Schenectady, NY, Xie, Ruilong, Niskayuna, NY, and Wang, Junli, Slingerlands, NY, for a “phase change memory cell with second conductive layer.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A method may include forming a via opening in a dielectric layer, depositing a first conductive layer along a bottom and a sidewall of the via opening, depositing a second conductive layer on top of the first conductive layer. The method may further include recessing the first conductive layer to form a trench and exposing a sidewall of the second conductive layer, depositing a non-conductive material in the trench, and depositing a phase change material layer on top of the dielectric layer. The top surface of the second conductive layer may be in direct contact with a bottom surface of the phase change material layer.”

The patent application was filed on July 18, 2019 (16/515,094).

Single-sided liner PCM cell for 3D crossbar PCM memory
International Business Machines Corp., Armonk, NY, has been assigned a patent (11,355,706) developed by Bruce, Robert L., White Plains, NY, BrightSky, Matthew Joseph, Armonk, NY, and Kim, SangBum, Suwanee, GA, for a “single-sided liner PCM cell for 3D crossbar PCM memory.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A cross-point memory array and stacked memory array structure. The memory array includes a plurality of first conductive line structures formed in a dielectric material layer, a plurality of memory elements, each memory element including a fill-in phase change memory (PCM) cell, and an access device enabling read or write access to said memory PCM structure, a plurality of second conductive line structures, the plurality of second conductive structures perpendicularly oriented relative to the plurality of first conductive structures. An individual memory element of the plurality of memory elements is conductively connected at a respective intersection between a first conductive line structure and a second conductive line structure. Each phase change memory (PCM) cell of a memory element at an intersection having a sub-lithographic conductive tuning liner disposed on only one sidewall of the PCM cell. The manufacturing maintains a minimal number of masking and processing steps.”

The patent application was filed on June 19, 2020 (16/906,506).

Phase change device with interfacing first and second semiconductor layers
International Business Machines Corp., Armonk, NY, has been assigned a patent (11,355,703) developed by Li, Ning, White Plains, NY, and Sadana, Devendra K., Pleasantville, NY, for “phase change device with interfacing first and second semiconductor layers.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “According to some embodiments of the present invention a phase change device (PCD) has a first and second semiconductor layer. The first semiconductor layer made of a first semiconductor material and has a first semiconductor thickness, a first interface surface, and a first electrode surface. The first interface surface and first electrode surface are on opposite sides of the first semiconductor layer. The first semiconductor material can transition between a first amorphous state and a first crystalline state at one or more first conditions. The second semiconductor layer is made of a second semiconductor material and has a second semiconductor thickness, a second interface surface, and a second electrode surface. The second interface surface and second electrode surface are on opposite sides of the second semiconductor layer. The first interface surface and the second interface surface are in electrical, physical, and chemical contact with one another at an interface. The second semiconductor material can transition between a second amorphous state and a second crystalline state at one or more second conditions. A first electrode in physical and electrical contact with the first electrode surface of the first semiconductor layer and a second electrode in physical and electrical contact with the second electrode surface of the second semiconductor layer. The first conditions and second conditions are different. Therefore, in some embodiments, the first and second semiconductor materials can be in different amorphous and/or crystalline states. The layers can have split amorphous/crystalline states. By controlling how the layers are split, the PCD can be in different resistive states.”

The patent application was filed on June 16, 2020 (16/903,245).

Semiconductor logic circuits including NVM cell
International Business Machines Corp., Armonk, NY, has been assigned a patent (11,322,202) developed by Gong, Nanbo, White Plains, NY, Ando, Takashi, Eastchester, NY, and Cohen, Guy M., Ossining, NY, for “semiconductor logic circuits including a non-volatile memory cell.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A phase change memory (PCM) device including a bottom electrode, a bottom heater over the bottom electrode, a bottom buffer layer over the bottom heater, a PCM region over the bottom buffer layer, a top buffer layer over the PCM region, a top heater over the top buffer layer, and a top electrode over the top heater.”

The patent application was filed on January 11, 2021 (17/145,632).

Phase change material switch and method of fabricating
International Business Machines Corp., Armonk, NY, has been assigned a patent (11,316,105) developed by Shen, Tian, Clifton Park, NY, Xie, Ruilong, Niskayuna, NY, Brew, Kevin W., Albany, NY, Wu, Heng, Guilderland, NY, and Zhang, Jingyun, Albany, NY, for “phase change material switch and method of fabricating same.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A phase change material switch includes a phase change layer disposed on a metal liner. A gate dielectric layer is disposed on the phase change layer. A metal gate liner is disposed on the gate dielectric layer.”

The patent application was filed on March 17, 2020 (16/821,660).