Using a hydrogen-terminated Si {111} surface as a substrate, we have grown Si nanowhiskers along the ⟨112⟩ direction by the vapor–liquid–solid mechanism. The minimum silicon core diameter was 3 nm and the maximum length was about 2 &mgr;m. The minimum silicon core diameter is close to the critical value for visible light emission due to the quantum confinement effect. In contrast to an oxidized Si surface, the hydrogen-terminated surface facilitates the formation of small molten Au–Si catalysts at a lower temperature (500&hthinsp;°C) which is slightly above the eutectic temperature. The formation of catalysts and the subsequent growth at the low temperature yield thin Si nanowhiskers on a Si substrate. ©1998 American Institute of Physics.