Modified LOCOS isolation process for semiconductor devices
US6001709A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 20, 1998 |
| Grant date | Dec 14, 1999 |
| Priority date | — |
| Expiry date | Apr 20, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B12/033
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A modified LOCOS isolation process for semiconductor devices is disclosed. First, a shielding layer is formed overlying a semiconductor substrate. The shielding layer is then patterned to form an opening that exposes a portion of the semiconductor substrate for forming a device isolation region. Next, oxygen ions are implanted with a tilt angle into the semiconductor substrate to form a doped region extending to the area under the margin of the shielding layer. A thermal oxidation process is then performed to form a field oxide layer on the semiconductor substrate. Since the oxidation rate of the area under the margin of the shielding layer is increased by the implanted oxygen ions, the bird's beak effect shown in conventional LOCOS process can be eliminated. After that, the shielding layer is removed to complete the fabricating process of this invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.