In this letter we report the synthesis of the semiconductor Ru2Si3 by ion i
mplantation into a silicon substrate. The formation of this compound has be
en confirmed by x-ray measurements and electron diffraction. The absorption
coefficient has been determined directly by optical transmission measureme
nts. The band gap is found to be direct with a value in the region of 0.9 e
V. (C) 1999 American Institute of Physics. [S0003-6951(99)03435-X].