Silicon Storage Technology, Inc.

Chunming Wang

Nhan Do

Xian Liu

Leo Xing

Melvin Diao

Guo Xiang Song

Andy Qiang Liu

Jack Sun

Yi Zhang

Feng Zhou

Chien-Sheng Su

Wen-Juei Lu

Andy Yang

Zufa Zhang

Shiuh Luen Wang

Guo Yong Liu

Baowei Qiao

Hieu Van Tran

Guangming Lin

Yaohua Zhu

Melvin Dao

A method of forming a memory device that includes forming a first insulation layer, a first conductive layer, and a second insulation layer on a semiconductor substrate, forming a trench in the second insulation layer to expose the upper surface of the first conductive layer, performing an oxidation process and a sloped etch process to reshape the upper surface to a concave shape, forming a third insulation layer on the reshaped upper surface, forming a conductive spacer on the third insulation layer, removing portions of the first conductive layer leaving a floating gate under the conductive spacer with the reshaped upper surface terminating at a side surface at a sharp edge, and forming a word line gate laterally adjacent to and insulated from the floating gate. The conductive spacer includes a lower surface that faces and matches the shape of the reshaped upper surface.

Split-gate flash memory cell with improved control gate capacitive coupling, and method of making same

A method of forming a semiconductor device by recessing the upper surface of a semiconductor substrate in first and second areas but not a third area, forming a first conductive layer in the three areas, forming a second conductive layer in all three areas, removing the first and second conductive layers from the second area and portions thereof from the first area resulting in pairs of stack structures each with a control gate over a floating gate, forming a third conductive layer in all three areas, forming a protective layer in the first and second areas and then removing the third conductive layer from the third area, then forming blocks of dummy conductive material in the third area, then etching in the first and second areas to form select and HV gates, and then replacing the blocks of dummy conductive material with blocks of metal material.

Method of forming a semiconductor device with memory cells, high voltage devices and logic devices on a substrate

A simplified method for forming a non-volatile memory cell using two polysilicon depositions. A first polysilicon layer is formed on and insulated from the semiconductor substrate in a first polysilicon deposition process. An insulation block is formed on the first polysilicon layer. Spacers are formed adjacent first and second sides of the insulation block, and with the spacer adjacent the first side is reduced. Exposed portions of the first poly silicon layer are removed while maintaining a polysilicon block of the first polysilicon layer disposed under the insulation block. A second polysilicon layer is formed over the substrate and the insulation block in a second polysilicon deposition process. Portions of the second polysilicon layer are removed while maintaining a first polysilicon block (disposed adjacent the first side of the insulation block), and a second polysilicon block (disposed adjacent the second side of the insulation block).

Method of forming a three-gate non-volatile flash memory cell using two polysilicon deposition steps

A memory device, and method of making the same, that includes a substrate of semiconductor material of a first conductivity type, first and second regions spaced apart in the substrate and having a second conductivity type different than the first conductivity type, with a first channel region in the substrate extending between the first and second regions, a first floating gate disposed over and insulated from a first portion of the first channel region adjacent to the second region, a first coupling gate disposed over and insulated from the first floating gate, a first word line gate disposed over and insulated from a second portion of the first channel region adjacent the first region, and a first erase gate disposed over and insulated from the first word line gate.

Method of making split-gate non-volatile memory cells with erase gates disposed over word line gates

Numerous embodiments are disclosed of improved architectures for storing and retrieving system data in a non-volatile memory system. Using these embodiments, system data is much less likely to become corrupted due to charge loss, charge redistribution, disturb effects, and other phenomena that have caused corruption in prior art non-volatile memory systems.

Architectures for storing and retrieving system data in a non-volatile memory system

The present invention relates to a flash memory device that uses strap cells in a memory array of non-volatile memory cells as source line pull down circuits. In one embodiment, the strap cells are erase gate strap cells. In another embodiment, the strap cells are source line strap cells. In another embodiment, the strap cells are control gate strap cells. In another embodiment, the strap cells are word line strap cells.

Non-volatile memory system using strap cells in source line pull down circuits

A method of forming a semiconductor device by recessing the upper surface of a semiconductor substrate in first and second areas but not a third area, forming a first conductive layer in the first and second areas, forming a second conductive layer in all three areas, removing the first and second conductive layers from the second area and portions thereof from the first area resulting in pairs of stack structures each with a control gate over a floating gate, forming a third conductive layer in the first and second areas, forming a protective layer in the first and second areas and then removing the second conductive layer from the third area, then forming blocks of conductive material in the third area, then etching in the first and second areas to form select and HV gates, and replacing the blocks of conductive material with blocks of metal material.

Method of making memory cells, high voltage devices and logic devices on a substrate

A method of forming a memory device that includes forming a first polysilicon layer using a first polysilicon deposition over a semiconductor substrate, forming an insulation spacer on the first polysilicon layer, and removing some of the first polysilicon layer to leave a first polysilicon block under the insulation spacer. A source region is formed in the substrate adjacent a first side surface of the first polysilicon block. A second polysilicon layer is formed using a second polysilicon deposition. The second polysilicon layer is partially removed to leave a second polysilicon block over the substrate and adjacent to a second side surface of the first polysilicon block. A third polysilicon layer is formed using a third polysilicon deposition. The third polysilicon layer is partially removed to leave a third polysilicon block over the source region. A drain region is formed in the substrate adjacent to the second polysilicon block.

Method of forming split-gate flash memory cell with spacer defined floating gate and discretely formed polysilicon gates

A method of forming a semiconductor device includes recessing the upper surface of first and second areas of a semiconductor substrate relative to the third area of the substrate, forming a pair of stack structures in the first area each having a control gate over a floating gate, forming a first source region in the substrate between the pair of stack structures, forming an erase gate over the first source region, forming a block of dummy material in the third area, forming select gates adjacent the stack structures, forming high voltage gates in the second area, forming a first blocking layer over at least a portion of one of the high voltage gates, forming silicide on a top surface of the high voltage gates which are not underneath the first blocking layer, and replacing the block of dummy material with a block of metal material.

Method of making memory cells, high voltage devices and logic devices on a substrate with silicide on conductive blocks

A method of forming memory cells, HV devices and logic devices on a substrate, including recessing the upper surface of the memory cell and HV device areas of the substrate, forming a polysilicon layer in the memory cell and HV device areas, forming first trenches through the first polysilicon layer and into the silicon substrate in the memory cell and HV device areas, filling the first trenches with insulation material, forming second trenches into the substrate in the logic device area to form upwardly extending fins, removing portions of the polysilicon layer in the memory cell area to form floating gates, forming erase and word line gates in the memory cell area, HV gates in the HV device area, and dummy gates in the logic device area from a second polysilicon layer, and replacing the dummy gates with metal gates that wrap around the fins.

Method of forming a device with planar split gate non-volatile memory cells, high voltage devices and FinFET logic devices

Split-gate non-volatile memory cells with erase gates disposed over word line gates, and method of making same

A memory device includes a semiconductor substrate, first and second regions in the substrate having a conductivity type different than that of the substrate, with a channel region in the substrate extending between the first and second regions. The channel region is continuous between the first and second regions. A first floating gate is disposed over and insulated from a first portion of the channel region. A second floating gate is disposed over and insulated from a second portion of the channel region. A first coupling gate is disposed over and insulated from the first floating gate. A second coupling gate is disposed over and insulated from the second floating gate. A word line gate is disposed over and insulated from a third portion of the channel region between the first and second channel region portions. An erase gate is disposed over and insulated from the word line gate.

Split-gate, 2-bit non-volatile memory cell with erase gate disposed over word line gate, and method of making same

A method of forming a memory device includes forming a second insulation layer on a first conductive layer formed on a first insulation layer formed on semiconductor substrate. A trench is formed into the second insulation layer extending down and exposing a portion of the first conductive layer, which is etched or oxidized to have a concave upper surface. Two insulation spacers are formed along sidewalls of the trench, having inner surfaces facing each other and outer surfaces facing away from each other. A source region is formed in the substrate between the insulation spacers. The second insulation layer and portions of the first conductive layer are removed to form floating gates under the insulation spacers. A third insulation layer is formed on side surfaces of the floating gates. Two conductive spacers are formed along the outer surfaces. Drain regions are formed in the substrate adjacent the conductive spacers.

Method of forming split gate memory cells

A pair of memory cells that includes first and second spaced apart trenches formed into the upper surface of a semiconductor substrate, and first and second floating gates disposed in the first and second trenches. First and second word line gates disposed over and insulated from a portion of the upper surface that is adjacent to the first and second floating gates respectively. A source region is formed in the substrate laterally between the first and second floating gates. First and second channel regions extend from the source region, under the first and second trenches respectively, along side walls of the first and second trenches respectively, and along portions of the upper surface disposed under the first and second word line gates respectively. The first and second trenches only contain the first and second floating gates and insulation material respectively.

Non-volatile memory cells with floating gates in dedicated trenches

A method of forming a non-volatile memory cell on a substrate having memory cell and logic circuit regions by forming a pair of conductive floating gates in the memory cell region, forming a first source region in the substrate between the pair of floating gates, forming a polysilicon layer in both regions, forming an oxide layer over the polysilicon layer in the logic circuit region, performing a chemical-mechanical polish of the polysilicon layer in the memory cell area leaving a first block of the polysilicon layer between the floating gates that is separated from remaining portions of the polysilicon layer, and selectively etching portions of the polysilicon layer to result in: second and third blocks of the polysilicon layer disposed in outer regions of the memory cell area, and a fourth block of the polysilicon layer in the logic circuit region.

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Shanghai, China

Chunming Wang