Abstract: An improved polycrystalline or polysilicon film having large grain size, such as 1 &mgr;m to 2 &mgr;m in diameter or greater, is obtained over the methods of the prior art by initially forming a silicon film, which may be comprised of amorphous silicon or micro-crystalline silicon or contains micro-crystal regions in the amorphous phase, at a low temperature via a chemical vapor deposition (CVD) method, such as by plasma chemical vapor deposition (PCVD) with silane gas diluted with, for example, hydrogen, argon or helium at a temperature, for example, in the range of room temperature to 600° C. This is followed by solid phase recrystallization of the film to form a polycrystalline film which is conducted at a relatively low temperature in the range of about 550° C. to 650° C. in an inert atmosphere, e.g., N or Ar, for a period of about several hours to 40 or more hours wherein the temperature is gradually increased, e.g., at a temperature rise rate below 20° C./min, preferably about 5° C.

Abstract: A high-performance thin-film semiconductor device and a simple fabrication method is provided. After a silicon film is deposited at approximately or less 580° C. and at a deposition rate of at least approximately 6 Å/minute, thermal oxidation is performed. This ensures an easy and simple fabrication of a high-performance thin-film semiconductor device. A thin-film semiconductor device capable of low-voltage and high-speed drive is provided. The short-channel type of a TFT circuit with an LDD structure reduces a threshold voltage, increases speed, restrains the power consumption and increases a breakdown voltage. The operational speeds of the thin-film semiconductor device is further increased by optimizing the maximum impurity concentration of an LDD portion, a source portion a drain portion, as well as optimizing the LDD length and the channel length. A display system is provided using these TFTs having drive signals at or below approximately the TTL level.

Abstract: In the formation of a thin-film transistor (620) capable of improving the OFF current characteristic, first, all ions (arrow Ion-1) generated from a mixed gas (doping gas) containing 5% PH.sub.3 with the remainder being H.sub.2 gas are implanted to a polycrystalline silicon film (604) at an approximately 80 keV energy level to achieve a P.sup.+ ion dose in the range from 3.times.10.sup.13 /cm.sup.2 to 1.times.10.sup.14 /cm.sup.2 in the process forming low concentration source-drain areas (602, 603). Next, all ions generated from a doping gas of pure hydrogen (arrow Ion-2) are implanted to the low concentration area (604a) at an approximately 20 keV energy level to achieve an H.sup.+ ion dose from 1.times.10.sup.14 /cm.sup.2 to 1.times.10.sup.15 /cm.sup.2. Then, the impurity is activated by heat treatment of the low concentration area (604a) implanted with impurity for approximately one hour at approximately 300.degree. C. in a nitrogen atmosphere.

Abstract: Electronic devices are provided with electrically conductive interconnections which are formed on the insulator material. Such electronic devices include, for example, thin film semiconductor devices (TFT), metal-insulator-metallic type non-wiring elements (MIM), solar cells, Large Scale Integration devices (LSI) or printed-wiring boards. At least a part of the electrically conductive interconnections are made of .alpha.-structure tantalum (Ta) which contains hydrogen. The .alpha.-structure tantalum does not have cubical crystals in its crystal system, but rather has body-centered cubes (bcc). The resistivity of the .alpha.-structure tantalum is from about 20 .mu..OMEGA. centimeters to about 60 .mu..OMEGA. centimeters. When hydrogen is included within this .alpha.-structure tantalum film, small amounts of nitrogen may be contained along with the hydrogen in the film.

Abstract: In the formation of a thin-film transistor (620) capable of improving the OFF current characteristic, first, all ions (arrow Ion-1) generated from a mixed gas (doping gas) containing 5% PH.sub.3 with the remainder being H.sub.2 gas are implanted to a polycrystalline silicon film (604) at an approximately 80 keV energy level to achieve a P.sup.+ ion dose in the range from 3.times.10.sup.13 /cm.sup.2 to 1.times.10.sup.14 /cm.sup.2 in the process forming low concentration source-drain areas (602, 603). Next, all ions generated from a doping gas of pure hydrogen (arrow Ion-2) are implanted to the low concentration area (604a) at an approximately 20 keV energy level to achieve an H.sup.+ ion dose from 1.times.10.sup.14 /cm.sup.2 to 1.times.10.sup.15 /cm.sup.2. Then, the impurity is activated by heat treatment of the low concentration area (604a) implanted with impurity for approximately one hour at approximately 300.degree. C. in a nitrogen atmosphere.

Abstract: In the production of silicon carbide, a starting composition comprising silicon dioxide powder and a carbonaceous substance and having a bulk density of 0.2 to 2.0 g/cm.sup.3 is used, wherein the silicon dioxide is covered with the carbonaceous substance and uniformly dispersed therein. The starting composition is produced by forming a kneaded mixture of silicon dioxide and high molecular weight organic compound, heating the kneaded mixture to conduct carbonization and thereby form a composite body and then granulating the composite body into 3 to 25 mm sized granules.

Abstract: Pyruvate oxidase can be produced by culturing Pediococcus sp. B-0667, Streptococcus sp. B-0668, Aerococcus viridans IFO-12219 or Aerococcus viridans IFO-12317. It is useful for analysis for pyruvic acid, because it catalyzes the reaction of pyruvic acid, phosphate and oxygen to form acetylphosphate, carbon dioxide and hydrogen peroxide. A kit containing the various reagents for such analysis is also provided by this invention.