Patent ID: 7983092

Claim:
A method of storing carriers in a body of a thin film transistor, wherein the thin film transistor includes a semiconductor layer formed over a substrate having a insulating surface, a gate insulating film formed over the semiconductor layer and a gate formed over the gate insulating film, wherein the semiconductor layer includes a body formed between a source and a drain, the method comprising the steps of: (a) providing a first drain voltage to the drain, a gate voltage to the gate and grounding the source at the same time, wherein when a Joule Heat resulted by the gate voltage and the first drain voltage is enough to cause the self-heating effect, majority carriers of the thin film transistor are induced to be stored in the body of the thin film transistor, and the threshold voltage of the thin film transistor is changed to complete a writing operation; and (b) providing a second drain voltage to the drain, a source voltage to the source and grounding the gate at the same time, wherein when a potential difference between the second drain voltage and the source voltage is enough to make the majority carriers stored in the body overcome the energy barrier in grain boundary of the body, the bias of the drain, and the source removes the majority carriers from the body of the semiconductor layer of the thin film transistor to complete an erasing operation.