A tuned and heated Langmuir probe has been used for combating the effect of radio frequency (rf) interference and contamination of the probe surface on the measurements in pure silane rf glow discharges. The measured probeI‐Vcharacteristic curves in the discharges were surprisingly reproducible over the period of 1 h. The non‐Maxwellian electron energy distribution functions in pure silane rf discharges have been successfully measured using the probe. The mean electron energy and electron density in the discharges have been inferred from the electron energy distribution functions. The experimental results have been used for selecting the optimum parameters of discharge conditions for depositing ana‐Si:H film with high quality at a high deposition rate of 1 nm/s.