A silicon object formation target substrate is arranged in a first chamber, a silicon sputter target is arranged in a second chamber communicated with the first chamber, plasma for chemical sputtering is formed from a hydrogen gas in the second chamber, chemical sputtering is effected on the silicon sputter target with the plasma thus formed, producing particles contributing to formation of silicon object, whereby a silicon object is formed, on the substrate, from the particles moved from the second chamber to the first chamber.