BACKGROUND OF THE INVENTION

1. Field of the Invention

The embodiments of the invention relate to a solar cell and, more particularly, to a solar cell including a semiconductor substrate.

2 Description of the Related Art

In recent years, as conventional energy resources such as Petroleum and coal are expected to be depleted, interest in alternative energy resources replacing these energy resources is on the rise. Of these, solar cells are attracting considerable attention as next generation cells which convert solar energy into electrical energy.

Such a solar cell may be manufactured by forming conductive type areas and electrodes electrically connected thereto on a semiconductor substrate in order to cause photoelectric conversion. In addition, the solar cell may include a passivation film for passivating a conductive type area, an anti-reflective film for preventing reflection and the like in order to improve properties of the solar cells.

In this regard, efficiency of conventional solar cells may be deteriorated due to recombination of carriers on the semiconductor substrate, long transfer distances of the carriers and the like. Accordingly, solar cells should be designed so that efficiency thereof can be maximized.

SUMMARY OF THE INVENTION

It is an object of the embodiment of the invention to provide a solar cell which is capable of maximizing efficiency.

In accordance with one aspect of the embodiment of the invention, the above and other objects can be accomplished by the provision of a solar cell including a semiconductor substrate, a first tunneling layer entirely formed over a surface of the semiconductor substrate, a first conductive type area disposed on the surface of the semiconductor substrate, and an electrode including a first electrode connected to the first conductive type area, wherein the first conductive type area includes a first portion which is disposed on the first tunneling layer and includes a polycrystalline, amorphous or microcrystalline semiconductor doped with a first conductive type dopant.

According to an embodiment of the invention, after the tunneling layer is formed on the semiconductor substrate, conductive type areas (emitter area, back surface field area and the like) are formed on the tunneling layer. As a result, defects on the back surface of the semiconductor substrate are effectively removed and carriers causing photoelectric conversion are efficiently transferred. Accordingly, damage to the semiconductor substrate is prevented and recombination sites on the back surface of the semiconductor substrate are thus efficiently removed. Accordingly, efficiency of the solar cells can be further improved.

In a solar cell according to another embodiment of the invention, conductive type areas include plurality portions disposed such that the tunneling layer is interposed between the portions, thereby minimizing recombination on the semiconductor substrate and improving electrical connection to electrodes. As a result, efficiency of the solar cells can be improved.

