Hydrogenated amorphous silicon (a-SiH) films were prepared by reactive dc magnetron sputtering under a wide range of conditions. The amount of hydrogen in the films CH and the nature of the Si–H bond were studied using infrared (IR) absorption and thermal evolution of H2. Hydrogen content varied between 2 and 40 at. %. The trends in the IR spectra are qualitatively similar to those previously reported. For low CH the thermal evolution spectra show a single peak centered around 600 °C, and with increasing CH, two additional peaks at ∼500 and 400 °C. A comparison of the IR and evolution spectra of the sputtered films yields an oscillator strength of 2.0×1019/cm2 for the 640 cm−1 wagging mode. This is 25% higher than the value previously reported for glow discharge and rf sputtered films. The hydrogen evolving from the 400 and 500 °C peaks correlates well with the integrated absorption of the 2100 cm−1 stretching mode. However, no good correlation is found between the high-temperature evolution peak and the 2000 cm−1 stretching mode. Our results enable us to define a CH independent oscillator strength for the 2100 cm−1 mode, but not for the 2000 cm−1 mode.