Etching end point judging method, etching end point judging device, and insulating film etching method using these methods
US6596551B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 1, 1999 |
| Grant date | Jul 22, 2003 |
| Priority date | — |
| Expiry date | Dec 1, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Etching end point judging method that includes the following steps in a dry etching end point judging method having a step of reducing noise of input signal waveforms using first digital filter, a step of obtaining a differential coefficient (primary or secondary) of a signal waveform from differential processing by operation circuit, a step of obtaining a smoothed differential coefficient value by reducing the noise components of the time series differential coefficient waveform that was obtained in the previous step, using the second digital filter, and a step of judging an etching end point by comparing the smoothed differential coefficient value and a preset value using discrimination method.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.