Abstract:
It is an object to form a high quality gate insulating film which is dense and has a strong insulation resistance property, and to propose a high reliable organic transistor in which a tunnel leakage current is little. One mode of the organic transistor of the present invention has a step of forming the gate insulating film by forming the conductive layer which becomes the gate electrode activating oxygen (or gas including oxygen) or nitrogen (or gas including nitrogen) or the like using dense plasma in which density of electron is 1011 cm−3 or more, and electron temperature is a range of 0.2 eV to 2.0 eV with plasma activation, and reacting directly with a portion of the conductive layer which becomes the gate electrode to be insulated.
Abstract:
Disclosed is a semiconductor device including: an insulating layer; a source electrode and a drain electrode embedded in the insulating layer; an oxide semiconductor layer in contact and over the insulating layer, the source electrode, and the drain electrode; a gate insulating layer over and covering the oxide semiconductor layer; and a gate electrode over the gate insulating layer, where the upper surfaces of the insulating layer, the source electrode, and the drain electrode exist coplanarly. The upper surface of the insulating layer, which is in contact with the oxide semiconductor layer, has a root-mean-square (RMS) roughness of 1 nm or less, and the difference in height between the upper surface of the insulating layer and the upper surface of the source electrode or the drain electrode is less than 5 nm. This structure contributes to the suppression of defects of the semiconductor device and enables their miniaturization.