The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 18, 2000
Filed:
Apr. 14, 1999
Szetsen Steven Lee, Hsinchu, TW;
Winbond Electronics Corp, Hsinchu, TW;
Abstract
A method for monitoring the presence of particles in a plasma etch chamber. It includes the steps of: (a) selecting at least one laser light source whose wavelength is at such an energy which will cause the particles to be monitored inside the plasma etch chamber to emit Raman, Stoke, and anti-Stoke spectra lines when the laser light is scattered by the particle; (b) emitting the laser light into an internal space of the plasma etch chamber; and (c) using a set of fiber optics to intercept light that may be scattered by the particle, if the particle is present in the plasma etch chamber; and (d) measuring amplitude and spectra of the scattered light. Because the intensity of the scattered light is proportional to the dielectric constant to the fourth power, the method is most advantageous for detect the presence of metal-containing particles, which have a very high dielectric constant. The spectral analysis also provides information relating to the chemical composition of the particles.