Patent ID: 7139200

Claim:
A method of identifying logical information in a programming by hot hole injection nitride electron storage (PHINES) cell by one-side reading, wherein the PHINES cell having a first region and a second region with a channel therebetween and having a gate above the channel but separate therefrom by an oxide-nitride-oxide gate dielectric layer, said method comprising: erasing both of the first region and the second region, and threshold voltage (Vt) increased with erasing time, wherein the threshold voltage is increased to a highest value V 1 after erasing is completed; programming, after erasing, at least one of the first region and the second region of the PHINES cell by hot hole injection, wherein the threshold voltage (Vt) is decreased with programming time; and reading a logical state of the PHINES cell by measuring an output current of one of the first region and the second region; wherein different quantity of the output current is caused by interaction between different quantity of the hot hole stored in the first region and the second region, the PHINES cell has at least four Vt levels, and the logical state of the PHINES cell is determined by one-side reading scheme.