b626bc89_tsugi_JP___Patent_applications__Description
[Patent application number] 20100032665 [Published] 02-11-2010 [Description] 
SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME - An embodiment is to include a staggered (top gate structure) thin film transistor in which an oxide semiconductor film containing In, Ga, and Zn is used as a semiconductor layer and a buffer layer is provided between the semiconductor layer and a source and drain electrode layers. The buffer layer having higher carrier concentration than the semiconductor layer is provided intentionally between the source and drain electrode layers and the semiconductor layer, whereby an ohmic contact is formed.
Kengo Akimoto, Atsugi JP - Patent applications