Patent ID: 9099498
Filing Date: 2015-08-04
Classification: H01L

Abstract:
1. A method for manufacturing a semiconductor device comprising the steps of: forming an oxide semiconductor film over a substrate during heat treatment to the substrate; forming a gate insulating film over the oxide semiconductor film; forming a first electrode over the gate insulating film; forming a first sidewall insulating film and a second sidewall insulating film on side surfaces of the first electrode; and adding a dopant to the oxide semiconductor film to form a first region, a pair of second regions and a pair of third regions of the oxide semiconductor film, wherein the first electrode overlaps with the first region, wherein the first sidewall insulating film overlaps with one of the pair of second regions, and the second sidewall insulating film overlaps with the other of the pair of second regions, wherein the first region and the pair of second regions are located between the pair of third regions, wherein the first region is a c-axis aligned crystalline oxide semiconductor region, wherein each of a crystallinity of the pair of second regions and a crystallinity of the pair of third regions is lower than a crystallinity of the first region, and wherein a dopant concentration of the pair of third regions is higher than a dopant concentration of the pair of second regions.