Observation of the amorphous-to-crystalline transition in silicon by Raman scattering

Raman scattering, electron diffraction, and dark-conductivity measurements have been made on so-called a-Si films deposited at various rf powers by a glow-discharge technique. These measurements show that an abrupt transition between amorphous and polycrystalline states occurred between 350 and 370 rf voltages and films deposited at high rf voltages are polycrystalline. Dark conductivity of the silicon films changed largely with the amorphous-to-crystalline transition. It is also observed that some polycrystallized silicon films exhibited new peaks between 505 and 513 cm−1 in the Raman spectra.