Patent ID: 6140183
Filing Date: 2000-10-31
Classification: H01L

Abstract:
A method of fabricating a semiconductor device having a DMOS transistor, comprising the steps of:forming a first oxide film on a semiconductor substrate of a first conductivity type;forming a gate electrode of the DMOS transistor on the oxide film using a first polycrystalline silicon film;oxidizing the polycrystalline silicon gate electrode;depositing a second polycrystalline silicon film onto the first oxide film;doping an impurity into the second polycrystalline silicon film;anisotropically etching the second polycrystalline silicon film, and patterning the second polycrystalline silicon film to form spacers formed of the second polycrystalline silicon film on side walls of the polycrystalline silicon gate electrode;forming a body region of the DMOS transistor comprising an impurity region of a second conductivity type by introducing an impurity having the second conductivity type into the semiconductor substrate of the first conductivity type with the polycrystalline silicon gate electrode and the second polycrystalline silicon spacers serving as a mask and a photoresist layer formed on the semiconductor substrate at a side of the gate electrode opposite the body region;diffusing the impurity of the second conductivity type by thermal annealing;selectively removing, by etching, the polycrystalline silicon spacers formed on the polycrystalline silicon side walls; anddoping an impurity of the first conductivity type into the semiconductor substrate of the first conductivity type and the body region of the second conductivity type.