ONE TIME PROGRAMMABLE READ-ONLY MEMORY (ROM) IN SOI CMOS

A programmable read-only-memory (ROM) cell and method of operating. The ROM cell comprises: a silicon-on-insulator (SOI) substrate having a bottom substrate layer, an insulating layer formed over said bottom substrate layer, and a top semiconductor substrate layer. A series coupled CMOS NFET and PFET device is formed at said semiconductor substrate layer, each NFET and PFET device having a respective gate, drain and source terminals, wherein a source terminal of said PFET device is electrically shorted to a drain terminal of said NFET device. An injected charge storage layer is provided at an interface between a channel formed beneath a gate terminal of said PFET and the insulating layer. The charge storage layer having trapped charge carriers representative of a logic bit value. The stored bit value is physically undetectable data. Biasing conditions established at the substrate and PFET device enable injection of charge carriers into the charge storage layer.