Transistor, a storage element

A semiconductor device less likely variation in electrical characteristics due to miniaturization. A first region, and a pair of second regions in contact with the side surface of the first region, the pair second A pair of third regions in contact of the side surface of the region, an oxide semiconductor film containing, first superimposed a gate insulating film provided over the oxide semiconductor film, a first region on the gate insulating film has a first electrode, a first region is a CAAC oxide semiconductor region, a pair of second regions and a pair of third region, an amorphous oxide semiconductor region containing a dopant There, the dopant concentration of the pair of third regions is a semiconductor device higher than the dopant concentration of the pair of second regions. .FIELD 1