A
transistor using
impact ionization and a method of manufacturing the same are provided. A
gate dielectric layer, a gate, and first and second spacers are formed on a
semiconductor substrate. A first
impurity layer is formed spaced from the first spacer and a second
impurity layer is formed expanding and overlapping with the second spacer therebelow, by performing slant
ion-implantation on the
semiconductor substrate using the gate and the first and second spacers as a
mask. A source and a drain are formed on the
semiconductor substrate to be self-aligned with the first and second spacers, respectively, thereby defining an
ionization region between the source and the drain in the semiconductor substrate. The source includes a first
silicide layer to form a schottky junction with the
ionization region. The drain includes a portion of the second
impurity layer overlapping with the second spacer and a second
silicide layer which is aligned with the second spacer to form an
ohmic contact with the second impurity layer.