Using localized ionizer to reduce electrostatic charge from wafer and mask
US6507474B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 19, 2000 |
| Grant date | Jan 14, 2003 |
| Priority date | — |
| Expiry date | Nov 2, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70941
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
One aspect of the present invention elates to a method of reducing electrostatic charges on a patterned photoresist to improve evaluation of the developed photoresist, involving the steps of evaluating the patterned photoresist to determine if electrostatic charges exist thereon; positioning an ionizer near the patterned photoresist, the ionizer generating ions thereby reducing the electrostatic charges on the patterned photoresist; and evaluating the patterned photoresist with an electron beam. Another aspect of the present invention relates to a system for reducing electrostatic charges on a patterned photoresist, containing a charge sensor for determining if electrostatic charges exist on the patterned photoresist and measuring the electrostatic charges; an ionizer positioned near the patterned photoresist having electrostatic charges thereon for reducing the electrostatic charges on the patterned photoresist; a controller for setting at least one of time of ion generation and amount of ion generation by the ionizer, the controller coupled to the charge sensor and the ionizer; and a scanning electron microscope or an atomic force microscope for evaluating the patterned photoresi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.