Growth of tungsten silicide (WSix) on tungsten (W) catalyzer surface is investigated by monitoring resistance change of heated W wire in silane (SiH4) atmosphere. To know a method suppressing the silicide formation, the effect of carbonization of W surface is also studied. Resistance change of heated W, observed in initial stage just after SiH4 introduction, is brought about increase in power consumption due to decomposition of SiH4. This power consumption can be drastically reduced when W surface is carbonized. Therefore, carbonization of tungsten surface is effective to stabilize the catalyzer temperature and to suppress W silicidation. (c) 2007 Elsevier B.V. All rights reserved.