SEMICONDUCTOR DEVICE AND A METHOD FOR MANUFACTURING THE SAME

摘要

PURPOSE: A semiconductor device and a manufacturing method thereof are provided to implement a stable electric property by forming an oxide semiconductor layer with a high crystallization region on a gate insulation layer. CONSTITUTION: An oxide semiconductor layer has a crystallization region on an under layer(901). A gate insulation layer is formed on the oxide semiconductor layer. A gate electrode overlaps the oxide semiconductor layer through the gate insulation layer. A pair of electrodes overlap a part of the oxide semiconductor layer. A value obtained by dividing a difference between a lattice constant of the oxide semiconductor layer and a distance of adjacent atoms in the under layer by the distance of the adjacent atoms in the under layer is 0.15 or less in a contact surface between the under layer and the oxide semiconductor layer.