Methods and a device for heat treating a semiconductor wafer having different kinds of impurities
US6426277B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 19, 1999 |
| Grant date | Jul 30, 2002 |
| Priority date | — |
| Expiry date | Oct 19, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/038
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method and a device for locally heating a semiconductor wafer having a first region of a first impurity and a second region of a second impurity having a diffusion rate different from that of the first impurity. A field oxide layer, a P well and an N well, gate oxide layers, gate electrodes, an N-type region and a P-type region are formed in sequence on or in a silicon wafer. The wafer is placed into a chamber. Then, a mask, which has a pattern for blocking the radiation from the heat source to the N well of the wafer, is positioned between the heat source and the wafer. The heat source emits radiation for heating the wafer, thereby the donor-type dopant atoms in the N-type region are diffused with a diffusion depth of d2 to form an electrically active region, but the acceptor-type dopant atoms in the P-type region are not diffused. After this step, a mask, which has a pattern for blocking the radiation from the heat source to the P well of the wafer, is positioned between the heat source and the wafer. The heat source emits radiation for heating the wafer, thereby the acceptor-type dopant atoms in the P-type region are diffused with a diffusion depth of d2 to form an electricall…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.