|
Abstract
Nowadays there are intensive research activities in developing solar energy since this kind of energy is
expected to be one of new energy sources that can solve world pollution problems. Polycrystalline
silicon solar cell whose production occupied the majority of aggregate production of solar cells is
regarded as a leading role of photovoltaic power. Development of fabrication technologies for high-
efficiency and low-cost polycrystalline silicon solar cell is a main topic that is of most concern.
Passivation is one of key technologies for high-efficiency solar cells and its role will become more
critical when the silicon wafers become thinner in the future. At present hydrogenated amorphous silicon
nitride (a-SiN:H) films prepared by plasma enhanced chemical vapor deposition (PECVD) using SiH4 and NH3
gases are mainly used as antireflection coating and passivation layers for silicon solar cells. However,
explosiveness of SiH4 gas and the process cost are needed to be concerned. We focus on hydrogenated
amorphous silicon carbon nitride (a-SiCN:H) films deposited by hot-wire CVD using hexamethyldisilazane
(HMDS), non-explosive and inexpensive material, and aim to optimize these films for passivation layers
of silicon solar cells. We investigated electrical, optical and passivating properties of a-SiCN:H films
and found that these films can act as an antireflection coating and provide good surface passivation. At
present, the efficiency of a cast polycrystalline silicon solar cell using a-SiCN:H as a passivation
layer reached 14.9% (2 cm x 2 cm). Experimental results up to now will be presented in this seminar.
|
