Abstract: A method of forming a self-aligned non-volatile device, includes, in part: forming trench isolation regions, forming a well between the trench isolation, forming a second well above the first well, forming a first oxide layer above a first portion of the second well, forming a first dielectric, a first polysilicon gate, and a second dielectric layer, respectively, above the first polysilicon layer, forming a first spacer above the body region and adjacent the first polysilicon layer, forming a second oxide layer above a second portion of the second well not covered by the first spacer, forming a second polysilicon gate layer above the second oxide layer, the first spacer and a portion of the second dielectric layer, removing the second polysilicon layer and the layers below it that are exposed in a via formed using a mask, thereby forming self-aligned source/drain regions.
Abstract: A method of forming a self-aligned non-volatile device, includes, in part: forming trench isolation regions, forming a well between the trench isolation, forming a second well above the first well, forming a first oxide layer above a first portion of the second well, forming a first dielectric, a first polysilicon gate, and a second dielectric layer, respectively, above the first polysilicon layer, forming a first spacer above the body region and adjacent the first polysilicon layer, forming a second oxide layer above a second portion of the second well not covered by the first spacer, forming a second polysilicon gate layer above the second oxide layer, the first spacer and a portion of the second dielectric layer, removing the second polysilicon layer and the layers below it that are exposed in a via formed using a mask, thereby forming self-aligned source/drain regions.
Abstract: In accordance with the present invention, a memory cell includes a non-volatile device and a DRAM cell. The DRAM cell further includes an MOS transistor and a capacitor. The non-volatile device include a control gate region and a guiding gate region that may partially overlap. The non-volatile device is erased prior to being programmed. Programming of the non-volatile device may be done via hot-electron injection or Fowler-Nordheim tunneling. When a power failure occurs, the data stored in the DRAM is loaded in the non-volatile devices. After the power is restored, the data stored in the non-volatile device is restored in the DRAM cell.
Abstract: In accordance with the present invention, a memory cell includes both non-volatile and SRAM cells. The non-volatile memory cell includes two MNOS transistors forming a differential pair. The SRAM cell includes a pair of MOS select transistors and a pair of cross-coupled MOS transistors. The MOS select transistors are adapted to couple the true and complement bitlines associated with the memory cell to various terminals of the cross-coupled MOS transistors, thereby to load data into the SRAM. During power-off, data is loaded from the SRAM into the non-volatile memory cell. During a subsequent read of the non-volatile memory cell, the SRAM is reloaded with data it had prior to the power-off. Because the MNOS transistors of the non-volatile memory cell operate differentially, data read errors caused by over-erase are reduced. Because the voltages applied during programming and erase cycle of the non-volatile memory cell are relatively small, the memory cell consumes relatively small amount of power.