Description:
Executive Summary
The invention involves a novel process and apparatus that use hollow cathode technology to improve any evaporation-based method for coating the surface of materials.
Background
Vapor deposition is a process for applying any form of coating to a material substrate. Although existing techniques are somewhat effective at performing vapor deposition, they typically face significant drawbacks. For instance, high flow rates of gas delivery are required, necessitating high-capacity pumps. In addition, with existing methods, the cathode-delivered gas jet is directed into the path of the vapor plume, causing many of the vapor particles to scatter away from the substrate; these particles are essentially wasted since much of the original vapor never reaches its intended destination. Such shortcomings limit the efficiency of current vapor deposition systems and have significant economic implications.
Invention Description
The invention is a process for improving the performance and efficiency of vapor deposition. This technology uses plasma, created using a hollow cathode, to assist in the vapor deposition process. The vapor is created by electron beam evaporation and then transported to a substrate for deposition by the implementation of a helium gas jet. The hollow cathode is positioned such that the plasma intercepts the vapor plume in a manner that is optimal for directing vapor, leading to more of the original vapor plume depositing in the desired location. Improved vapor direction, coupled with decreased gas flow requirements, promises to significantly improve current vapor deposition systems.
Advantages
In contrast to existing vapor deposition systems, this invention:
- Enables more-precise vapor deposition, allowing a greater percentage of the original vapor plume to reach the substrate and thereby significantly increasing efficiency.
- Requires less gas with a lower pump capacity, translating to reduced operational cost.
- Directs the plasma flow coaxially with the vapor stream, allowing for an array of vapor streams that can be swept across the surface and thereby increasing directional range of deposition.
- Can be designed with enhanced insulating capacity, allowing for convenient performance heating and etching.
Potential Applications
The invention can be utilized to enhance any evaporation-based method of surface coating for any material of interest, such as component coating for improved surface protection, substrate surface etching or battery substrate electrolyte deposition.
