The PACE project has developed an additive, UV-assisted process for the catalysis of electroless plating based upon the use of a photocatalyst whose photoactivity was tailored to the narrow emission band of an excimer lamp source operating in the range of the UV spectrum which is transmissible through air and quartz.
The PACE process has the potential for widespread exploitation in the production of microelectronics and microsystems requiring selective metallisations (for example of copper, nickel, or gold) of a high resolution. While demonstrated for electroless copper plating, the process could be used also for electroless nickel, and with some adaptation for electroless gold plating. The process may also enable selective direct electrolytic plating.
The PACE process avoids the substrate damage associated with laser scribing to define interconnect metallisation patterns on metallised insulators.
The key results of the PACE project are:
* - the PACE process - a photoselective activation process for electroless plating based on a photocatalyst appropriate for use with the 222 nm excimer lamp source
* - development of a new family of photosensitive catalysts for electroless plating
* - development of a high intensity multi-element excimer lamp UV source
* - integration of the multi-element excimer lamp UV source in a contact mask aligner
* - design of an industrial scale large volume synthesis for the chosen photocatalyst
* - a laboratory scale general purpose photoprocessor chamber
High specification metallisation of electrically insulating materials is increasingly required in sensor, multifunctional micro systems, hybrid electronics, optics, and display technologies. Currently, industrial scale selective electroless deposition is limited to the selective plating of metallised areas on already patterned substrates, or the use of laser of ion beam writing processes. Photon processing offers an alternative to physically scribing a pattern on the substrate. The development of the dielectric barrier (silent) discharge excimer lamp has recently provided a technology potentially enabling large area selective electroless metallisation via a photo-induced activation process. In conjunction with the development of ultraviolet (UV) sensitive activation precursors this technology will allow the selective activation of those areas of the substrate where metal is required by selective UV irradiation through a mask. The PACE project is based upon the exploitation of both of these recent advances and will open a route for rapid, high volume, low cost metallisation processing.
The primary objective of the PACE project is the development of a cost-effective process for selective electroless deposition on unpatterned insulating materials utilising a novel UV lamp-assisted activation pre-process.
Funding SchemeCSC - Cost-sharing contracts
50013 Campi Bisenzio (Fi)
LA12 9QG Ulverston
WC1E 7JE London