METHOD FOR FORMING TRANSISTOR OF SEMICONDUCTOR DEVICE TO IMPROVE LEAKAGE CURRENT CHARACTERISTIC AND AVOID VARIATION OF THRESHOLD VOLTAGE OF CHANNEL REGION

摘要

PURPOSE: A method for forming a transistor of a semiconductor device is provided to improve a leakage current characteristic by using an oxynitride layer as a gate insulation layer instead of an oxide layer, and to avoid variation of a threshold voltage of a channel region by preventing the boron ions implanted into a gate electrode of a PMOS(p-type metal oxide semiconductor) from passing through a channel region. CONSTITUTION: A predetermined thickness of an oxide layer is formed on a semiconductor substrate(41) having a well. The surface of the oxide layer is nitridized by a plasma nitrification method to form a nitride layer. The nitride layer is oxidized to be an oxynitride layer(54) so that a gate insulation layer of a stack structure in which the oxide layer and the oxynitride layer are stacked is formed. A transistor is formed.