Other

Central Glass Company, Limited

Agency of Industrial Science and Technology

Agency of Industrial Science

Akihisa Matsuda

Michio Kondo

Yoshimi Watabe

Yoshihiko Chida

Norikazu Ito

Takashi Hayakawa

Hideo Yamagishi

Masataka Kondo

Yoshiyuki Nasuno

Satoshi Mashima

Makoto Toda

Kenji Wada

Kouji Fujita

A solar cell substrate has irregularities on a surface which is in contact with a photo-electric conversion layer, and light is incident on the side of the irregularities. The height of the irregularities is set so that the root mean square height is in a range of 15 nm to 600 nm, and tan &thgr; is in a range of 0.10 to 0.30, where &thgr; is the angle of incline of the surface of the irregularities with respect to an average line of the irregularities. Light incident on the irregularities is scattered at the interface. This increases the optical path length and thus the quantity of light absorbed in the photo-electric conversion layer, resulting in improved efficiency. Additionally, the photo-electric conversion layer can be made thinner reducing deposit time and manufacturing cost. Further, collision of crystals is not incurred, thus preventing deterioration of photo-electric conversion efficiency which is caused by defects.

Solar cell substrate, thin-film solar cell, and multi-junction thin-film solar cell

A thin film forming method and apparatus forms a thin film having an excellent thickness uniformity over a substrate, particularly a large-area substrate. The thin film forming method and apparatus includes a film forming chamber in which an inductive coupling electrode having a feeding portion and a grounding portion at its two ends is arranged, a high-frequency power source for feeding a high-frequency power to the feeding portion, and a waveform generator for amplitude-modulating the high-frequency power outputted from the high-frequency power source. The amplitude-modulated high-frequency power is fed to the inductive coupling electrode to generate a plasma so that a thin film may be formed on a substrate arranged to face the inductive coupling electrode.

Thin film formation by inductively-coupled plasma CVD process

A substrate is disposed in a reactor kept to be a vacuum state, a material gas is supplied into a space in front of the substrate, high-frequency electric power is supplied to the material gas to generate plasma based on electric discharge excitation in the front space of the substrate, and an amorphous silicon thin film is deposited on the substrate by chemical vapour deposition. Further, an electrode section comprising tubular electrodes supplying the material gas through a plurality of gas discharge openings, and tubular electrode sucking and evacuating gases to the outside through a plurality of gas suction openings. Thereby, a higher silane gas and the like generated during the film deposition can be removed from a reactive region immediately, and a thin film is deposited on the substrate surface with the same condition of the film deposition at any spot of the substrate surface. Consequently, the amorphous silicon thin film with film quality may be deposited on the large-area substrate.

Plasma CVD apparatus suitable for manufacturing solar cell and the like

The disclosure relates to an amorphous silicon thin film transistor. The transistor includes a substrate, a gate electrode formed on the substrate, an insulating film formed on the substrate, a hydrogenated amorphous silicon film formed on the insulating film, a non-doped microcrystal silicon film formed on the amorphous silicon film; and source and drain electrodes which are formed on the microcrystal silicon film. In the transistor, there is provided an ohmic contact between the source and drain electrodes through the microcrystal silicon film. The insulating film optionally has an etched surface layer prepared by etching the insulating film which has been formed on the substrate, with an aqueous solution containing HF. The TFT can be produced in a simple manner with safety and with a simple equipment.

Amorphous silicon thin film transistor and method of preparing same

The disclosure relates to a microcrystal silicon thin film transistor; The transistor includes a substrate, a gate electrode formed on the substrate, an insulating film formed on the substrate, a non-doped microcrystal silicon film formed on the insulating film, and source and drain electrodes which are formed on the microcrystal film. In the transistor, there is provided an ohmic contact between the source and drain electrodes through the microcrystal silicon film. The insulating film optionally has an etched surface layer prepared by etching the insulating film which has been formed on the substrate, with an aqueous solution containing HF. The TFT can be produced in a simple manner with safety and with a simple equipment.

Microcrystal silicon thin film transistor

The invention relates to a plasma CVD method for the deposition of a thin film of amorphous silicon, or an amorphous silicon alloy, on a substrate by glow discharge decomposition of a raw material gas such as silane gas. The degradation of the photoconductivity of the obtained amorphous silicon film by irradiation with light is suppressed by mixing xenon gas with the raw material gas such that at the entrance to the reaction chamber the volume ratio of xenon gas to the raw material gas is not less than 1 and, preferably, not more than 30. A nearly comparable effect can be gained, and the material cost can be reduced, by mixing 1 part by volume of the raw material gas with 0.05 to 1 part of xenon gas and 5 to 30 parts of hydrogen gas.

Growing community of inventors

Tsuchiura, Japan

Akihisa Matsuda