Influence of the dilute-phase SiH bond concentration on the steady-state defect density in a-Si:H

In the field of the stability of a-Si:H, the received wisdom is that a high clustered-phase SiH concentration is to be avoided. In this high-intensity illumination study of a-Si:H films grown using different techniques, it is found that the steady-state defect density is proportional to the dilute-phase concentration [SiH]_d below ≈ 16%. A model is proposed to quantify the participation of the different H-bonding configurations in the metastability phenomena. It predicts a steady-state defect density proportional to [SiH]_d and accurately describes the recently observed changes in the infrared absorption of the various H-bonding configurations during light-soaking.