Film deposition experiments on the QCM crystals show that the film formation is highly dependent on the polarity of the applied bias voltage (Fig. ), which is in agreement with our previous results, where 40 nm silver on Si (100) was used as a substrate. In the present study, a positive bias voltage of +40 V, which attracts electrons from the plasma to the QCM crystal, led to a significant mass evolution, i.e., film deposition in a continuous CVD process, as seen in Fig. . In contrast, a negative bias voltage of -40 V, which repels plasma electrons at the QCM sensor, showed almost no increase in mass evolution.