Real-time studies of amorphous and microcrystalline Si:H growth by spectroscopic ellipsometry and infrared spectroscopy

摘要

We have applied real-time spectroscopic ellipsometry (SE) and infrared attenuated total reflection spectroscopy (ATR) simultaneously to study microscopic growth processes of amorphous and microcrystalline Si:H thin films. In the microcrystalline silicon (μc-Si:H) growth by plasma-enhanced chemical vapor deposition, real-time SE results revealed μc-Si:H nucleation from the amorphous phase, followed by the coalescence of isolated μc-Si:H grains exposed on growing surfaces. The onset of the μc-Si:H grain growth and the coalescence of μc-Si:H grains was readily characterized by monitoring surface roughness evolution using real-time SE. The structural evolution determined by SE showed excellent relationships with SiH_n (n = 1-2) local bonding structures determined by ATR. By combining the results obtained from real-time SE and ATR, the microscopic growth processes of Si:H thin films are characterized.