Enhanced cathodic arc source for arc plasma deposition

Abstract

The invention provides an enhanced cathodic arc source for arc plasma deposition. An improved cathodic arc source and method of DLC film deposition with a carbon containing directional-jet plasma flowproduced inside of cylindrical graphite cavity with depth of the cavity approximately equal to the cathode diameter. The generated carbon plasma expands through the orifice into ambient vacuum resulting in plasma flow strong self-constriction. The method represents a repetitive process that includes two steps: the described above plasma generation / deposition step that alternates with a recovery step. This step provides periodical removal of excessive amount of carbon accumulated on the cavity wall by motion of the cathode rod inside of the cavity in direction of the orifice. The cathode rod protrudes above the orifice, and moves back to the initial cathode tip position. The said steps periodically can be reproduced until the film with target thickness is deposited. Technical advantages include the film hardness, density, and transparency improvement, high reproducibility, long duration operation, and particulate reduction.

Description

technical field [0001] The present invention relates generally to techniques for thin film deposition using cathodic arc plasma sources, and more particularly to techniques suitable for the repeatable deposition of ultrahard and / or ultradense, low defect carbon films. Background technique [0002] Improving wear and corrosion resistance as well as sliding behavior is an important consideration in the field of thin film technology. These applications represent a wide variety of difficult operating conditions, often co-existing, such as adhesive, abrasive and corrosive interactions with sliding counterparts and the surrounding media. Diamond-like carbon ("DLC") coatings appear to fulfill many of these needs as protective layers: DLC represents a high mechanically hard material characterized by high hardness and Young's modulus. Additionally, it exhibits only a weak adhesion affinity for metals and most other materials. It is inert to most aggressive agents and environments. ...

AI Technical Summary

Problems solved by technology

Although metal, metal-compound, and DLC films have been synthesized, large particle filters suffer from two major drawbacks: (1) inefficient plasma transport, i.e. only a fraction of the initial plasma is actually used for film deposition, and (2) Large particles cannot be completely removed

Said flow expansion typically results in plasma cooling effects, ion deceleration and hence reduction in sp3 / sp2 ratio (and hardness, density, transparency); and "parasitic" carbon deposits on the anode surface which cause target The deposition rate of the carbon film on the

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