| 摘要 |
A flat-cell ROM array includes a bank of field effect transistors, each having a source, drain and gate, formed by ion implantation between columns of buried N+ and under rows of polysilicon, wherein adjacent columns of buried N+ are the source and drain of at least one transistor and a corresponding row of polysilicon is the gate of the transistor. Each of these transistors is programmed to have one of a plurality of threshold voltages depending on a desired storage value. Attached to the bank of transistors is an upper selector network associated with the bank connected to a first class of alternating sets of the columns, and a lower selector network associated with the bank connected to a second class of alternating sets of the columns. A method provides steps for performing the present invention. |
