Effects of hydrogen dilution on electron density in multi-hollow discharges with magnetic field for A-Si:H film deposition

We have measured dependence of electron density n_e on hydrogen dilution ratio R= [H₂]/([SiH₄]+[H₂]) in the multi-hollow discharges with or without magnetic fields to obtain information about the deposition rate enhancement due to hydrogen dilution and applying the magnetic fields. The R dependence of the n_e did not correlate with that of the deposition rate. The n_e exponentially decreases with a distance from the discharges z. The n_e decreases faster for higher R. These complicated behaviors of n_e may be explained by electron attachment to the clusters generated in the SiH₄+H₂ discharges. For R=0, the n_e was almost same value regardless with or without magnetic fields. For R=1, n_e with magnetic fields was 1/10 of that without magnetic fields. We also found that, for R=0, n_e drastically decreased with increasing the z, while for R=1, ne showed a gradual decrease with z. The effects of applying magnetic fields on the deposition are unclear but applying the magnetic fields may affect the electron energy distribution.