US Patent 7339229 Nonvolatile memory solution using single-poly pFlash technology

A single-poly two-transistor PMOS memory cell for multiple-time programming applications includes a PMOS floating gate transistor sharing a drain/source P+ diffusion region with a PMOS select gate transistor all formed within a first n-well. A control plate for the floating gate transistor is formed in a second n-well. A single-poly two-transitor PMOS memory cell for one-time programming applications includes a PMOS floating gate transistor having a source formed as a p+ diffusion region in a single n-well. The source is adapted to also serve as control plate for the floating gate transistor.