摘要 |
A gate electrode is formed above an n-type well including an n-type threshold voltage adjustment region, ions of p-type impurity are implanted with a low acceleration energy to form extension regions in the n-type well on both sides of the gate electrode, side wall spacers are formed on the side walls of the gate electrode, ions of p-type impurity are implanted with a small dose causing substantially no abnormal tailing in the gate electrode and with a relatively high acceleration energy to form p-type source/drain regions deeper than the threshold adjustment region, ions of atoms are implanted into the semiconductor substrate to change the upper parts of the gate electrode and the source/drain regions to amorphous state, ions of p-type impurity are implanted with a large dose to form high-concentration parts in the source/drain regions, and the impurities introduced by the ion implantation are activated.
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