Methods for fabricating metal-oxide-semiconductor field effect transistors using gate sidewall spacers

Abstract

Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) is fabricated by forming gate spacers on both sidewalls of a gate pattern in a semiconductor substrate including first and second regions. Then, a first impurity region is formed in the semiconductor substrate at the first region, and the gate spacer exposed at the first region is removed. A second impurity region is formed in the semiconductor substrate at the first region. A third impurity region is formed at the semiconductor substrate in the second region, and the gate spacer exposed at the second region is removed. A fourth impurity region is formed in the semiconductor substrate at the second region. The first and third impurity regions are formed deeper than the second and fourth impurity regions.