Abstract: 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.

Abstract: 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.

Abstract: A solar cell substrate of the present invention 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. According to this arrangement, the 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. As a result, photo-electric conversion efficiency can be improved and the photo-electric conversion layer can be made thinner, thereby greatly reducing deposit time and manufacturing cost required for the photo-electric conversion layer.

Abstract: The present invention is to provide a thin film forming method and apparatus which make it possible to form a thin film having an excellent thickness uniformity over a large-sized substrate.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A filter rod for filtering the smoke of a cigarette including an acetate tow having a high crimp modulus and the acetate tow is bloomed and wrapped by a paper to form the filter rod, wherein a degree of crimping of the acetate tow at a position just downstream of a delivery roller of a filter rod making machine used to form a filter rod is 1.4 or more, and is obtained by conditions satisfying the following equations by having the crimping operation performed under the conditions satisfying the following equations (1) and (2): ##EQU1## wherein: A stands for the weight percent of acetone of the acetate tow just after the tow is fed from a stuffing box type crimping apparatus; andT stands for a temperature of the acetate tow just after the tow is fed from the stuffing box type crimping machine.

Abstract: 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.

Abstract: An acetate tow having crimp modulus, wherein a degree of crimping of the acetate tow at a position just downstream of a delivery roller of a filter rod making machine used to form a filter rod is 1.4 or more.When the acetate tow is bloomed in the filter rod making machine, a tendency which the acetate tow is caught on a feed roller becomes very low, and when the filter rod is formed of the acetate tow, a filter rod having a high pressure drop can be obtained.The present invention further includes a method of manufacturing the acetate tow, in which a specified acetone content is maintained in the acetate tow and a specified temperature, determined on the basis of the acetone content, is used in a process of crimping the acetate tow.

Abstract: A silicon thin film is composed of primarily silicon atoms, 0 to 8 atm % hydrogen, at least one element selected from the group including fluorine, chlorine, bromine and iodine, and an impurity element, wherein about 80 to 100% of microcrystalline grains are interspersed in an amorphous phase. The thin film is produced by deposition on a substrate in a plasma atmosphere using as a raw material gas silane (SiH.sub.4) or halogenated silane (SiH.sub.o--3 X.sub.4--1) wherein X represents a halogen or a combination of two or more halogens, and a dopant gas mixed with the raw material gas. The method comprises the steps of: (1) diluting the mixed gas with hydrogen in a ratio of the diluting gas to the raw material gas of from 50:1 to 100:1, to control the film deposition rate to produce a layer including mixed crystalline and amorphous substances; and (2) applying an electric power to provide a plasma discharge power density of from 0.1 to about 0.5 W/cm.sup.2, at a reaction pressure of 5 to 10 torr.

Abstract: a-type or n-type thin film of silicon has the concentration of an impurity dopant element decreased adjacent to a boundary of film. The impurity dopant element in the portion of the silicon film from the surface to a predetermined depth is replaced by an element selected from the group consisting of fluorine, chlorine, bromine, iodine, and hydrogen.

Abstract: An amorphous photovoltaic energy conversion element for use in a solar cell is composed of a first layer formed of a p-type material, a second layer formed of an intrinsic amorphous semiconductor having a potential gradient formed therein and a third layer formed of a metal capable of coming into ohmic contact with the aforementioned intrinsic layer of amorphous semiconductor and exhibiting a lower work function than the work function of the intrinsic layer of amorphous semiconductor.

Abstract: A method of producing thin films of silicon is characterized in that a p-type or n-type thin film of doped silicon having a dopant or impurity element is placed in a plasma atmosphere of elements selected from the group consisting of fluorine, chlorine, bromine, iodine, and hydrogen, whereby the concentration of an impurity element in the thin film is decreased adjacent to the surface of thin film and accordingly the impurity element is replaced by the plasma element adjacent to the surface of the thin film.

Abstract: A tunable optical device is produced by forming in the surface of a substrate a fan-shaped grating of continuously varying period by means of a holographic technique using a photoresist and twisted mirrors, coating the surface of the substrate containing the formed grating with a polyurethane film and diffusing a dye in the prescribed region of the resultant polyurethane film coated on the substrate. In the device of the construction described above, irradiation of the region having the fan-shaped grating with a laser light generates laser light beams whose wavelength is variable with the position at which the laser light impinges upon the region of the grating.