| 摘要 |
PURPOSE:To obtain high threshold voltage even when the dosage of channel doping is low by a method wherein the threshold voltage of an MISFET is controlled by the selection of conductivity type of the semiconductor layer, which constitutes a gate electrode, and the doping of a channel. CONSTITUTION:The word wire WL1 provided on a gate insulating film 3 consists of a p-type semiconductor layer 4 and the high melting point metal silicide provided on the layer 4. On the other hand, n<+> type semiconductor regions 8 and 9 are provided in a semiconductor substrate 1. MISFET Q1 and Q2 are formed using the word wire WL1, the regions 8 and 9 as a gate electrode, a source electrode and a drain region. In this, case, as the word wire WL1 is constituted using the layer 4, the difference in the work function between the gate electrode and the substrate 1 can be made larger when compared with the case wherein an n-type semiconductor layer is used instead of the layer 4. Accordingly, the dosage of the channel doping can be reduced in the amount of increase in the above-mentioned difference. As a result, the deterioration in characteristics of the FET Q1 and Q2 can be prevented effectively. |
