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:
Mar. 04, 2014
Filed:
Jul. 01, 2009
Kamal Hadidi, Somerville, MA (US);
Rajesh Dorai, Woburn, MA (US);
Bernard G. Lindsay, Danvers, MA (US);
Vikram Singh, North Andover, MA (US);
George D. Papasouliotis, North Andover, MA (US);
Kamal Hadidi, Somerville, MA (US);
Rajesh Dorai, Woburn, MA (US);
Bernard G. Lindsay, Danvers, MA (US);
Vikram Singh, North Andover, MA (US);
George D. Papasouliotis, North Andover, MA (US);
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Abstract
A method is disclosed for adjusting the composition of plasmas used in plasma doping, plasma deposition and plasma etching techniques. The disclosed method enables the plasma composition to be controlled by modifying the energy distribution of the electrons present in the plasma. Energetic electrons are produced in the plasma by accelerating electrons in the plasma using very fast voltage pulses. The pulses are long enough to influence the electrons, but too fast to affect the ions significantly. Collisions between the energetic electrons and the constituents of the plasma result in changes in the plasma composition. The plasma composition can then be optimized to meet the requirements of the specific process being used. This can entail changing the ratio of ion species in the plasma, changing the ratio of ionization to dissociation, or changing the excited state population of the plasma.