Patent ID: 7645342
Filing Date: 2010-01-12
Classification: C23C,C30B,H01L

Abstract:
1. A conductive filament for resistive heating in vapor deposition, said filament comprising: a cathode contact and an anode contact; a plurality of adjacent arc-shaped filament portions between said contacts, said plurality of arc-shaped filament portions having a generally concentric arrangement; a plurality of respective semicircular turns connecting pairs of said arc-shaped filament portions, wherein a plurality of connected adjacent arc-shaped filament portions define corresponding arc-shaped openings therebetween; and a plurality of said semicircular turns having an enlarged inner circumference and a width across the filament portion at said turn that is less than the width across said adjacent arc-shaped filament portions for reducing the difference in resistance between the inner and outer edges of said semicircular turn as current flows through said filament between said contacts.