Semiconductor device having first and second oxide semiconductors with difference energy level
US9761738B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2017 |
| Grant date | Sep 12, 2017 |
| Priority date | — |
| Expiry date | Feb 14, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10K59/1213
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
To provide a semiconductor device which has transistor characteristics with little variation and includes an oxide semiconductor. The semiconductor device includes an insulating film over a conductive film and an oxide semiconductor film over the insulating film. The oxide semiconductor film includes a first oxide semiconductor layer, a second oxide semiconductor layer over the first oxide semiconductor layer, and a third oxide semiconductor layer over the second oxide semiconductor layer. The energy level of a bottom of a conduction band of the second oxide semiconductor layer is lower than those of the first and third oxide semiconductor layers. An end portion of the second oxide semiconductor layer is positioned on an inner side than an end portion of the first oxide semiconductor layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.