Patent · US Expired

Induction plasma system

US4306175A · kind A · utility

16Cited by
8References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 29, 1980
Grant dateDec 15, 1981
Priority date
Expiry dateFeb 29, 2000

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05H1/30
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

An induction plasma system includes a plasma chamber, a high frequency electrical coil that surrounds the chamber, and an oscillator for energizing the coil to establish a plasma maintaining condition in the chamber. The oscillator tank circuit includes the coil, and is tuned so that it is essentially at resonance when a plasma condition is established in the chamber. Ignition means is arranged for initiating a plasma condition, and is constructed such that insertion of the ignition means into the chamber in the absence of a plasma condition shifts the impedance condition in the chamber to essentially the same tuned condition that exists when a plasma condition is established in the plasma chamber, but without need to adjust any component of the tank circuit.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.