| dc.description.abstract | In this thesis, the fabrication process and performance of the nanocrystalline silicon (nc-Si) p-i-n solar cells was studied. Firstly, the nc-Si:H films were deposited with a PECVD (plasma-enhanced chemical vapor deposition) system, by employing four different process techniques: (1) attaching a stainless steel mesh to cathode of the PECVD system, (2) an a-Si:H buffer layer was deposited on the substrate before growing the nc-Si:H film, (3) applying additional in-situ H2-plasma treatment on the a-Si:H buffer layer before growing the nc-Si:H film, and (4) the SiH4 reaction gas was diluted in H2 ,and the crystallinity of the obtain films were compared. The nc-Si:H films were characterized with micro-Raman spectroscopy, X-ray diffraction (XRD) and field-emission scanning electron microscope (FE-SEM). From the measurment results, it was concluded that depositing an a-Si:H buffer layer and then applying in-situ H2-plasma treatment on a-Si:H buffer layer could result in the better crystallinity of the grown nc-Si:H film.
Then, two different structures of nc-Si:H p-i-n solar cell were fabricated and their characteristics such as the short-circuit current ( Isc ), open-circuit voltage ( Voc ),fill factor ( FF )and efficiency ( eff. ) were measured. For the device structures, one was Al / n-a-Si:H / i-a-Si:H / p-a-SiC:H / ITO (indium tin oxide) /glass and the other was Al / n-a-Si:H / i-nc-Si:H / i-a-Si:H ( buffer layer )/ i-a-Si:H / p-a-SiC:H / ITO /glass. The measured results showed that the former one had a higher efficiency (~ 1.08%) and the later one had a little higher FF (~ 0.278) under AM1.5. | en_US |