Abstract Diamond-like carbon films are prepared by high power pulsed sputtering with a configuration of two facing targets. The discharge is called Penning discharge. Peak value of instantaneous power which is consumed in the plasma confined in a compact space reaches more than 10 kW in spite of an average power of 36–38 W. Growth rate is around 0.16–0.2 μm per hour in the pressure range from 0.5 to 2 Pa. In the Raman spectra, two very broad overlapping bands extending between 1200 and 1700 cm − 1 are assigned as the D (disorder) and G (graphite) bands. Both the intensity ratio of D band to G band and the G peak position do not strongly depend on the pressure at the pressure less than 1 Pa, beyond which the G peak position somewhat shifts to higher wavenumber and the intensity ratio increases. Meanwhile, the full width at half maximum of the G peak monotonically decreases with increasing pressure. In XPS C1s core level spectra, the rate of sp 3 C bond related area is about 43–44% at the pressure lower than 1 Pa, beyond which the rate gradually decreases to about 38% with increasing pressure up to 2 Pa. The pressure dependence on the rate of sp 3 C bond is reasonably consistent with the analysis of the Raman parameters. The hardness of films exceeds 25 GPa at the pressure less than 1 Pa, whereas the films with a moderate hardness of about 16.5 GPa are prepared at the pressure higher than 1 Pa.