Low pressure diamond film deposition is an important emerging technology still at the precommercial stage worldwide, which has many important potential applications. To date there has been little serious European research on this topic.
This project aims to bring a European research consortium up to and beyond the forefront of this technology by designing and fabricating optimized hardware for diamond film deposition, and by systematically mastering the chemistry of the deposition process.
The main result of the project is an in-line process to coat optical fibers with DLC films. The process is capable to function at relatively higher pressures of up to 5 Torr thus reducing the sealing and differential pumping requirements. CeramOptec has filed a patent application on this process. The process uses a hydrocarbon (CH4 or C2 H2) Helium mixture as precursor gas and deposition takes place at speeds of up to 3 m/min in a reactor chamber equipped with vertical electrodes in close vicinity of the fiber axis. A RF frequency of 40 kHz is typically used to generate a plasma column of approximately 40 cm length. The deposited films appear hermectic thicknesses of 200 A and of DLC nature.
It is believed that this coating technology will be useful for other substrates and FORBAIRT intends to use it in future research and cooperation projects.
The fundamental relationships between various DLC film properties such as hardness, colour, structure and deposition conditions were published by FORBAIRT and have advanced the state of the art of DLC coating research. The successful deposition of true diamond films by FORBAIRT at relatively high rates is another achievement that will form the basis for future cooperative research and technology transfer projects by this organisation.
DSE successfully produced deposition equipment for plasma assisted CVD and engineering solutions for leaktight, contact free reactor chamber feed through. This engineering and system know how will help DSE to enter new markets.
Based on the know how gained with microwave plasmas in the course of the project CeramOptec has successfully developed a process for the manufacturing of fiberoptic preforms. The process is now successfully used to produce specialty preforms for CeramOptecs own consumption thus saving well over 500 000 ECU per year in costs and providing the company with increased flexibility and a wider product line.
Furthermore, we intend to develop an application for the technology by focusing specifically on the coating of optical fibres to improve their long-term reliability. This will be a major innovation.
The main quantified targets are to produce diamond film coated optical fibres with stress corrosion susceptibility factors > 200 at fibre drawing speeds up to 10 m/s. The successful achievement of these targets would result in world leadership in fibre optic technology for European industry.
The project will also lay the foundations for other commercial applications of diamond technology in various engineering and electronics markets.