  Thermoelectric properties of the chemically-doped intermetallic narrow-band
semiconductor FeGa3 are reported. The parent compound shows semiconductor-like
behavior with a small band gap (Eg = 0.2 eV), a carrier density of ~ 10(18)
cm-3 and, a large n-type Seebeck coefficient (S ~ -400 \mu V/K) at room
temperature. Hall effect measurements indicate that chemical doping
significantly increases the carrier density, resulting in a metallic state,
while the Seebeck coefficient still remains fairly large (~ -150 \mu V/K). The
largest power factor (S2/{\rho} = 62 \mu W/m K2) and corresponding figure of
merit (ZT = 0.013) at 390 K were observed for Fe0.99Co0.01(Ga0.997Ge0.003)3.
