Abstract:
A method of forming a semiconductor device with memory cells and logic devices on the same silicon-on-insulator substrate. The method includes providing a substrate that includes silicon, a first insulation layer directly over the silicon, and a silicon layer directly over the first insulation layer. Silicon is epitaxially grown on the silicon layer in a first (memory) area of the substrate and not in a second (logic device) area of the substrate such that the silicon layer is thicker in the first area of the substrate relative to the second area of the substrate. Memory cells are formed in the first area of the substrate, and logic devices are formed in the second area of the substrate.
Abstract:
A non-volatile memory cell including a semiconductor substrate having a fin shaped upper surface with a top surface and two side surfaces. Source and drain regions are formed in the fin shaped upper surface portion with a channel region there between. A conductive floating gate includes a first portion extending along a first portion of the top surface, and second and third portions extending along first portions of the two side surfaces, respectively. A conductive control gate includes a first portion extending along a second portion of the top surface, second and third portions extending along second portions of the two side surfaces respectively, a fourth portion extending up and over at least some of the floating gate first portion, and fifth and sixth portions extending out and over at least some of the floating gate second and third portions respectively.
Abstract:
The disclosed embodiments comprise a flash memory device that can be configured to operate as a read only memory device. In some embodiments, the flash memory device can be configured into a flash memory portion and a read only memory portion.
Abstract:
The present invention relates to a flash memory system wherein one or more circuit blocks utilize fully depleted silicon-on-insulator transistor design to minimize leakage
Abstract:
A memory device that includes a plurality of ROM cells each having spaced apart source and drain regions formed in a substrate with a channel region therebetween, a first gate disposed over and insulated from a first portion of the channel region, a second gate disposed over and insulated from a second portion of the channel region, and a conductive line extending over the plurality of ROM cells. The conductive line is electrically coupled to the drain regions of a first subgroup of the ROM cells, and is not electrically coupled to the drain regions of a second subgroup of the ROM cells. Alternately, a first subgroup of the ROM cells each includes a higher voltage threshold implant region in the channel region, whereas a second subgroup of the ROM cells each lack any higher voltage threshold implant region in the channel region.
Abstract:
Systems and methods are disclosed for providing selective threshold voltage characteristics via use of MOS transistors having differential threshold voltages. In one exemplary embodiment, there is provided a metal oxide semiconductor device comprising a substrate of semiconductor material having a source region, a drain region and a channel region therebetween, an insulating layer over the channel region, and a gate portion of the insulating layer. Moreover, with regard to the device, the shape of the insulating layer and/or the shape or implantation of a junction region are of varied dimension as between the gate-to-drain and gate-to-source junctions to provide differential threshold voltages between them.
Abstract:
A memory device that includes a plurality of ROM cells each having spaced apart source and drain regions formed in a substrate with a channel region therebetween, a first gate disposed over and insulated from a first portion of the channel region, a second gate disposed over and insulated from a second portion of the channel region, and a conductive line extending over the plurality of ROM cells. The conductive line is electrically coupled to the drain regions of a first subgroup of the ROM cells, and is not electrically coupled to the drain regions of a second subgroup of the ROM cells. Alternately, a first subgroup of the ROM cells each includes a higher voltage threshold implant region in the channel region, whereas a second subgroup of the ROM cells each lack any higher voltage threshold implant region in the channel region.
Abstract:
A method of forming a memory device on a semiconductor substrate having a memory region (with floating and control gates), a first logic region (with first logic gates) and a second logic region (with second logic gates). A first implantation forms the source regions adjacent the floating gates in the memory region, and the source and drain regions adjacent the first logic gates in the first logic region. A second implantation forms the source and drain regions adjacent the second logic gates in the second logic region. A third implantation forms the drain regions adjacent the control gates in the memory region, and enhances the source region in the memory region and the source/drain regions in the first logic region. A fourth implantation enhances the source/drain regions in the second logic region.
Abstract:
A circuit and method are disclosed for operating a non-volatile memory device, comprising time sampling a reference current or voltage in a floating holding node to obtain a hold voltage and applying the hold voltage in sensing circuitry.
Abstract:
A non-volatile memory device comprises a semiconductor substrate of a first conductivity type. An array of non-volatile memory cells is located in the semiconductor substrate and arranged in a plurality of rows and columns. Each memory cell comprises a first region on a surface of the semiconductor substrate of a second conductivity type, and a second region on the surface of the semiconductor substrate of the second conductivity type. A channel region is between the first region and the second region. A word line overlies a first portion of the channel region and is insulated therefrom, and adjacent to the first region and having little or no overlap with the first region. A floating gate overlies a second portion of the channel region, is adjacent to the first portion, and is insulated therefrom and is adjacent to the second region. A coupling gate overlies the floating gate. A bit line is connected to the first region. During the operations of program, read, or erase, a negative voltage can be applied to the word lines and/or coupling gates of the selected or unselected memory cells.