Method for manufacturing thin film transistor using multi-tone mask
US8242494B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 2009 |
| Grant date | Aug 14, 2012 |
| Priority date | — |
| Expiry date | May 25, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D30/0312
Abstract
An object is to manufacture a semiconductor device including an oxide semiconductor at low cost with high productivity in such a manner that a photolithography process is simplified by reducing the number of light-exposure masks. In a method for manufacturing a semiconductor device including a channel-etched inverted-staggered thin film transistor, an oxide semiconductor film and a conductive film are etched using a mask layer formed with the use of a multi-tone mask which is a light-exposure mask through which light is transmitted so as to have a plurality of intensities. In etching steps, a first etching step is performed by wet etching in which an etchant is used, and a second etching step is performed by dry etching in which an etching gas is used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.