Ž . Applied Surface Science 109r110 1997 462–466 Area selective laser chemical vapor deposition of diamond and graphite Mikael Lindstam ) , Mats Boman, Jan-Otto Carlsson Department of Inorganic Chemistry, Uppsala UniÕersity, Box 531, S-751 21 Uppsala, Sweden Received 4 June 1996; accepted 28 October 1996 Abstract High quality diamond and graphite has been deposited area selectively on silicon substrates in a hot filament chemical Ž . vapor deposition reactor employing laser heating. A mixture of CH 1–3 vol% and H was passed over a tantalum 4 2 filament having a temperature of approximately 22008C. A laser beam was used to raise the temperature locally on the substrate surface. By a proper choice of filament temperature, substrate background temperature and laser induced temperature, isolated islands of polycrystalline diamond or graphite could be deposited on the silicon substrate. The deposited diamond and graphite spots were characterized by micro-Raman spectroscopy, scanning electron microscopy and scanning force microscopy. 1. Introduction Ž Vapor deposited carbon diamond, diamond like . carbon, turbostratic carbon, graphite etc. has a unique variation of properties. Hardness, for exam- ple, can be varied from the hardest known solid Ž . Ž . diamond to a soft lubricating material graphite . Diamond like carbon, on the other hand, can be deposited with a hardness higher than TiN but with better tribological properties. Some of the carbon phases have potential use as biocompatible material. Ion-selective electrodes, used in analytical chemistry or medicine, are another application where well char- acterized vapor deposited carbon is of interest. Of particular interest are miniaturized devices in carbon-biosensors and microelectrodes. Normally, ) Corresponding author. Tel.: q46-18-183738; fax: q46-18- 503056; e-mail: mikaell@kemi.uu.se. patterning by lithographic techniques is needed for w x the miniaturization 1–5 . In this paper, area selective deposition of either the diamond phase or the graphite phase on silicon Ž . 100 substrates is described. The deposition method uses a hot filament process which is combined with laser heating. It is a single step process with the freedom of patterning of substrate areas down to the m m level. 2. Experimental A schematic of the experimental set-up is shown in Fig. 1. The stainless steel CVD-reactor is water cooled. A gas handling system with mass flow me- ters was used to provide the reactor with the reaction gas mixture, CH and H . A pressure controller was 4 2 0169-4332r97r$17.00 Copyright q 1997 Elsevier Science B.V. All rights reserved. Ž . PII S0169-4332 96 00921-X