Method of reducing transistor channel length with oxidation inhibiting spacers

摘要

A method of fabricating a transistor. A dielectric layer is formed on an upper surface of a semiconductor substrate. A photoresist layer is then deposited on a dielectric layer and patterned with a photolithography exposure device to expose a region of the dielectric layer having a lateral dimension approximately equal to the minimum feature size resolvable by the photolithography exposure device. The exposed region of the dielectric layer is then removed to form a trench in the dielectric layer having opposed dielectric sidewalls and to expose a channel region of the semiconductor substrate having a lateral dimension approximately equal to the minimum feature size. First and second spacer structures are then formed on the respective dielectric sidewalls. The spacer structures shadow peripheral portions of the exposed channel region. A channel dielectric is then formed between the first and second spacer structures. An outer surface of the spacer structure is then removed to expose peripheral portions of the channel region. A first concentration of a first impurity is then introduced into the peripheral portions of the semiconductor substrate and the channel dielectric is thereafter removed. A gate dielectric is then formed on the semiconductor substrate and a conductive gate structure, such as polysilicon, is formed over the gate dielectric.