摘要 |
A non-volatile memory cell capable of storing two bits of information having a non-conducting charge trapping dielectric, such as silicon nitride, layered in association with at least one electrical dielectric layer, such as an oxide, with a P-type substrate and an N-type channel implanted in the well region of the substrate between two source/drain regions is disclosed. The N-type channel achieves an inversion layer without the application of bias voltage to the gate of the memory cell. A method that implants the N-type channel in the P-type substrate of the cell wherein the N-type channel lowers the un-programmed or programmed voltage threshold of the memory cell to a value lower than would exist without the N-type channel is disclosed. The N-type channel reduces the second bit effect such that the window of operation between the programmed and un-programmed voltage thresholds of the bits is widened.
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