| 摘要 |
PURPOSE:To improve reliability in proportion to a decrease in yielding amount of hot carriers without obstructing miniaturization, by covering low- concentration, third impurity diffused layers having shallower diffusion depth than second impurity diffused layers and in contact with the second impurity diffused layers, which act as a drain region with a gate electrode completely. CONSTITUTION:N<+> type impurity diffused layers 19 and 20 are formed on the main surface of a P-type silicon substrate 18 with a specified interval being provided. N<-> type impurity diffused layers 21 and 22, whose diffusing depth is shallower than the impurity diffused layers 19 and 20 and impurity concentration is lower, are formed on the main surface of the substrate 18 between both layers so as to contact the diffused layers 19 and 20. A gate electrode 24 is formed on the silicon substrate 18 between the impurity diffused layers 19 and 20 by way of a gate insulating film 23 so as to cover the impurity diffused layers 21 and 22 completely. Thus the yielding amount of hot carriers can be reduced, reliability is improved correspondingly and miniaturization is made possible.
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