Materials and Interface Optimization of Heterojunction Silicon (HIT) Solar Cells Using in-situ Real-Time Spectroscopic Ellipsometry

摘要: We have applied real-time spectroscopic ellipsometry (RTSE) as both an in-situ diagnostic and post-growth analysis tool for hydrogenated amorphous silicon (a-Si:H)/crystalline (c-Si) heterojunction with intrinsic thin-layer (HIT) solar cells grown by hot-wire chemical vapor deposition. RTSE enables precise thickness control of the 5 to 25 nm layers used in these devices, well monitoring crystallinity surface roughness real time. Utilizing feedback, but without extensive optimization, we achieved a photovoltaic energy conversion efficiency 14.1% on Al-backed p-type Czochralski c-Si wafer coated thin i n front. Open-circuit voltages above 620 mV indicate effective passivation a-Si:H layer. Lifetime measurements using resonant coupled photoconductive decay that recombination velocities can approach 1 cm/s. transmission electron microscopy show i-layers grow mixture nano-crystalline silicon.