Sanyo Electric Co., Ltd.

Yoichiro Aya

Keiichi Sano

Naoya Sotani

Yasuki Harata

Hiroki Hamada

Daisuke Ide

Yukihiro Noguchi

Hisashi Abe

Yasuo Nakahara

Norihiro Terada

Masaaki Kameda

Tomoyuki Nouda

A method of fabricating a semiconductor device capable of fabricating a semiconductor device including a polycrystalline semiconductor film having excellent characteristics with a high yield is provided. A first amorphous semiconductor film is formed on a substrate. A conductive film is formed on the first amorphous semiconductor film. The conductive film is irradiated with an electromagnetic wave such as a high-frequency wave or a YAG laser beam thereby making the conductive film generate heat and converting the first amorphous semiconductor film to a first polycrystalline semiconductor film through the heat. Thus, polycrystallization is homogeneously performed without dispersion through the heat from the conductive film irradiated with the electromagnetic wave. Consequently, an excellent first polycrystalline silicon film can be formed with an excellent yield.

Method of fabricating a thin film transistor using electromagnetic wave heating of an amorphous semiconductor film

A method is obtained of manufacturing a semiconductor device including a semiconductor layer with high field-effect mobility. According to the semiconductor device manufacturing method, a semiconductor layer is formed on a substrate and then the semiconductor layer is irradiated with high energy beam. Then, a heat treatment is provided under a temperature condition capable of reducing the surface roughness of the semiconductor layer. The radiation of high energy beam toward the semiconductor layer improves the crystalinity of the semiconductor layer and the subsequent heat treatment reduces the surface roughness of the semiconductor layer to enhance the field-effect mobility of the semiconductor layer.

Method of manufacturing a semiconductor device

A photovoltaic element is produced by forming a plurality of layers of amorphous semiconductor thin films on a substrate, whereby at least one of the plurality of layers contains an impurity that hinders crystallization resulting from thermal annealing, and then thermally annealing the amorphous semiconductor thin films thereby crystallizing the film except for the layer containing the impurity. In the finished photovoltaic element, the resulting crystalline semiconductor film and the non-crystallized, amorphous semiconductor film can form a heterojunction. The amorphous film can be arranged closer to the substrate, i.e. between the crystalline film and the substrate.

Photovoltaic element and method of manufacturing the same

The content of bonding hydrogen in an a - SiGe film is so adjusted that in a case where the content of bonding hydrogen per Si atom in the film is in the range of approximately 8 to 14 at. %, [SiH.sub.2 ]/[Si] and [SiH]/[Si] are respectively in the ranges of approximately 0.5 to 4 at. % and approximately 7 to 10 at. %, and both [SiH.sub.2 ]/[Si] and [SiH]/[Si] increase at approximately equal slops as the content of bonding hydrogen increases.

Amorphous silicon germanium film and semiconductor device using the same

In a photovoltaic device, when an internal electric field in a photoelectric conversion layer becomes non-uniform in the surface direction of the layer for a reason such as the interface between a transparent conductive film and the photoelectric conversion layer being formed in an irregular shape, the internal electric field in the photoelectric conversion layer is made uniform by (1) making the thickness of an intrinsic layer inside the photoelectric conversion layer in portions of the photoelectric conversion layer where the internal electric field becomes weak smaller than that in the other portions, (2) providing regions where conductivity is high and activation energy is low in the photoelectric conversion layer in the said portions, or (3) containing a ferroelectric material in a portion of the intrinsic layer inside the photoelectric conversion layer.

Photovoltaic device

A semiconductive film is formed on a substrate having a surface with indentations defining a plurality of plane regions and elevated step difference portions between adjacent plane regions. The semiconductive film is irradiated with energy beams to be polycrystallized, whereby the positions of the crystal grain boundaries in the polycrystalline semiconductive film are controlled.

Polycrystalline semiconductive film, semiconductor device using the same

A polysilicon thin film obtained by using a heat treatment to crystallize an amorphous silicon thin film formed on a substrate has substantially no grain boundaries present in the direction of its thickness, i.e. substantially no grain boundaries extend across the thickness direction. Such a polysilicon thin film can be prepared by forming a doped first amorphous silicon layer containing dispersed crystal phases on a substrate, forming an undoped second amorphous silicon layer on the first amorphous silicon layer, and crystallizing the first and second amorphous silicon layers by heat treatment.

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Hirakata, Japan

Yoichiro Aya