As microelectronic device and computer components are reduced to sub-micron size there is a need for metal features of nanometre thickness. At the Naval Research Laboratory, Washington, a method has been developed for fabricating platinum patterns of varied geometry which may be as little as 20 nm thick and with heights of up to 700 nm. These are produced by thermal decomposition of a platinum precursor molecule, tetrakis-(trifluorophosphine)-platinum, onto the surface of a contoured substrate. A detailed description of the fabrication process, and an analysis of the properties and morphology of the platinum film structures have recently been published (D. S. Y. Hsu, N. H. Turner, K. W. Pierson and V. A. Shamamian, J. Vac. Sei Technol. B, 1992, 10, (5), 2251–2258).

The substrate is amorphous silicon, fabricated by lithographic techniques suitable for large scale processing, and this permits a very thin polycrystalline platinum film to be deposited, which in turn makes possible the production of ultranarrow patterns with 20 nm linewidths. It is suggested that further reduction in linewidth is possible by improving various parameters.