APPARATUS INCLUDING IMPROVED CATHODE FOR CONTINUOUS DEPOSITION OF AMORPHOUS MATERIAL

摘要

A continuous system for depositing at least one layer of amorphous semiconductor material upon a substrate. Feed and takeup reels advance a thin film substrate through the system. At least one chamber is located intermediate the feed and takeup reels wherein a plasma is generated by a glow discharge of a reaction gas mixture. Apparatus associated with the chamber provides close regulation of plasma/substrate surface equilibrium to assure that a uniform layer of amorphous material is deposited. A chamber cathode, including a top surface electrode is adapted to provide a substantially uniform distribution of reaction gas during deposition by means of a plurality of baffles that equalizes path lenghts from a reaction gas source to the electrode and from the electrode to a vacuum chamber. The electrode is electrically insulated from a plurality of gas exits to confine the plasma to the region between the electrode and the active surface of the substrate. Additional subsystems include a servo-controlled reel drive to regulate substrate tension and and an inert gas curtain to isolate the interior of the chamber.