Furnace for rapid thermal processing with optical switching film disposed between heater and reflector
US6047107A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1997 |
| Grant date | Apr 4, 2000 |
| Priority date | — |
| Expiry date | Dec 19, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67115
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A furnace (1) for Rapid Thermal Processing of a wafer (7), characterized in that the wafer (7) is heated by lamps (9), and the heat radiation is reflected by an optical switching device (15,17) which is in the reflecting state during the heating stage. During the cooling stage of the wafer (7), the heat is absorbed by the switching device (15,17), which is in the heat-absorbing state. The switching device comprises a switching film of a trivalent metal, such as gadolinium, which is capable of forming hydrides by an exchange of hydrogen. Dependent on the hydrogen concentration of the hydrides, the film reflects or absorbs heat. The hydrogen content in the switching film can be changed by varying the partial pressure of hydrogen, or, preferably, by varying the potential of the switching film forming part of a stack of layers in an electrochemical cell.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.