Abstract: In a semiconductor device, the degree of flatness of 0.3 nm or less in terms of a peak-to-valley (P-V) value is realized by rinsing a silicon surface with hydrogen-added ultrapure water in a light-screened state and in a nitrogen atmosphere and a contact resistance of 10?11 ?cm2 or less is realized by setting a work function difference of 0.2 eV or less between an electrode and the silicon. Thus, the semiconductor device can operate on a frequency of 10 GHz or higher.

Abstract: An accumulation mode transistor has an impurity concentration of a semiconductor layer in a channel region at a value higher than 2×1017 cm?3 to achieve a large gate voltage swing.

Abstract: An accumulation mode transistor has an impurity concentration of a semiconductor layer in a channel region at a value higher than 2×1017 cm?3 to achieve a large gate voltage swing.

Abstract: With inversion-mode transistors, intrinsic-mode transistors, or semiconductor-layer accumulation-layer current controlled accumulation-mode transistors, variation in threshold voltages becomes large in miniaturized generations due to statistical variation in impurity atom concentrations and thus it is difficult to maintain the reliability of an LSI. Provided is a bulk current controlled accumulation-mode transistor which is formed by controlling the thickness and the impurity atom concentration of a semiconductor layer so that the thickness of a depletion layer becomes greater than that of the semiconductor layer. For example, by setting the thickness of the semiconductor layer to 100 nm and setting the impurity concentration thereof to be higher than 2×1017 [cm?3], the standard deviation of variation in threshold values can be made smaller than a power supply voltage-based allowable variation value.

Abstract: On a surface of a semiconductor substrate, a plurality of terraces formed stepwise by an atomic step are formed in the substantially same direction. Using the semiconductor substrate, a MOS transistor is formed so that no step exists in a carrier traveling direction (source-drain direction).

Abstract: In a semiconductor device, the degree of flatness of 0.3 nm or less in terms of a peak-to-valley (P-V) value is realized by rinsing a silicon surface with hydrogen-added ultrapure water in a light-screened state and in a nitrogen atmosphere and a contact resistance of 10?11 ?cm2 or less is realized by setting a work function difference of 0.2 eV or less between an electrode and the silicon. Thus, the semiconductor device can operate on a frequency of 10 GHz or higher.

Abstract: An accumulation mode transistor has an impurity concentration of a semiconductor layer in a channel region at a value higher than 2×1017 cm?3 to achieve a large gate voltage swing.