High resolution cross-sectioning of polysilicon features with a dual beam tool
US7094616B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 4, 2004 |
| Grant date | Aug 22, 2006 |
| Priority date | — |
| Expiry date | Aug 26, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2001/2873
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for high resolution cross sectioning of polysilicon features with a dual electron (E) beam and focused ion beam. The method comprises consecutive steps of encapsulating the polysilicon features of interest with a metal coating, followed by ion beam cross sectioning of the metal encapsulated polysilicon features, followed by electron (E) beam and gas (XeF2) etching and cleaning of the polysilicon from the encapsulating metal to remove the polysilicon while leaving the polysilicon surface features preserved in the encapsulating metal. The method is practiced with a dual beam tool comprising a scanning electron microscope (SEM) and a focused ion beam tool. Advantageously, in the electron (E) beam and gas etching and cleaning step, the cleaning and imaging are simultaneous, allowing E beam imaging while the cleaning is taking place to evaluate the extent of cleaning. The step of etching and cleaning is followed by scanning electron microscope (SEM) imaging and evaluation of the metal preserved polysilicon features.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.