Non-volatile memory devices having floating-gates FETs with different source-gate and drain-gate border lengths

摘要

Non-volatile memory (NVM) devices are disclosed. In one aspect, a NVM device may include a substrate, and a field-effect transistor (FET). The FET may include a first doped region in the substrate and a second doped region in the substrate. The first and the second doped regions may define a channel region of the substrate between them. An insulating layer may overlie the channel region. A floating gate may overlie the insulating layer. Charge of an amount that encodes a value may be stored on the floating gate. The floating gate and the first and the second doped regions may be shaped such that the floating gate defines with the first doped region a first border of a first length, and the floating gate defines with the second doped region a second border of a second length that is less than 90% of the first length.