High Speed Laser Crystallization of Nanoparticle Ink for Thin Film Solar Cells at Room Temperature

摘要

Cost effective and rapid thermal processing technique called direct pulsed laser crystallization (DPLC) is introduced to crystallize photovoltaic nanoparticle ink for thin film solar cell applications at room temperature and atmospheric pressure. DPLC improves the optical and electrical properties of the absorbent thin film by reducing internal defects of such as inter-crystal gaps and grain boundaries. CuInSe2 nanoparticle ink formed film was used as demonstration in current study, its film resistivity decreases by two orders of magnitude and hall mobility of charge carriers increases by two orders of magnitude as a result of DPLC. Band gap shrinkage (AEg) of CIS thin film after DPLC leads to broader acceptance of solar spectrum up to 100 nm. A typical increase of 7.9% (visible range) and 19.2% (near infrared range) in optical absorptance is obtained under optimal DPLC conditions.