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Fomnation of giant-grain copper thin films on SiO 2 by a low-kinetic energy particle process followed by thermal annealing has been investigated. When Cu films are grown on SiO 2 by the process under a sufficient amount of energy deposition, they exhibit almost perfect crystal orientation conversion from Cu(111) to Cu(100) upon themnal annealing. Such crystal orientation conversion is accompanied by the giant grain growth in the film as large as 100 μm. With regard to these phenomena, the effects of the ion flux density and of the ion bombardment energy have been studied

Crystallinity recovery, impurity activation and stress relief in a heavily ion-implanted layer by ultrahigh-vacuum ion-implantation during low-temperature annealing were investigated and the following results were obtained. The crystallinity of the layer heavily doped with arsenic ions was recovered at 550°C for 75 min and the impurities were activated sufficiently. Furthermore, the impurity level distribution supported the LSS theory and the maximum carrier concentration was 1.6 × 1020 cm−3. The reverse current of the p-n junction formed by this method was two orders of magnitude lower than that in a conventional device. In the p-n junction formed by continuous ion implantation of arsenic and phosphorus to relieve the stress in the implanted layer, the reverse current decreased further. When the stress was most relieved, the carrier activation rate was highest and the p-n junction reverse current was lowest.

Low kinetic energy particle process in which the surface of the sputter‐deposited thin film is concurrently bombarded with low energy ions during the entire period of film growth has been established by employing a newly developed RF‐dc coupled mode bias sputtering technology. Applying this process to pure aluminum metallization, various improvements in the properties of aluminum thin films have been achieved, i.e., the crystallinity enhancement as well as excellent surface smoothness has been realized. Furthermore, hillock‐free aluminum thin films have been also obtained by this process, which is of paramount importance in realizing reliable multilevel interconnection scheme for ultralarge scale integrated circuits.

Teratogenic effects of azosemide, a loop diuretic, were investigated in rats, mice and rabbits. Azosemide was given orally to pregnant rats, mice and rabbits during organogenesis. The pregnant animals were killed at term and their fetuses were examined for external, visceral and skeletal abnormalities. In rats, azosemide at 10–30 mg/kg/day did not affect intrauterine growth, resorptions and rates of external and visceral malformations. Treatment with 90 mg/kg/day resulted in a significant increase in skeletal abnormalities such as wavy ribs, bent scapula and bent humerus. However, the skeletal abnormalities observed in term fetuses could not be found in adult offspring, indicating that they were temporary. In mice, 1250 mg/kg/day of azosemide caused maternal death, abortion, and retarded maternal and fetal weight. Treatment with 200–500 mg/kg/day did not induce fetal mortalities, external and visceral malformations. Skeletal abnormalities increased in dose-dependent fashion. The type of abnormalities was identical to that encountered in rat fetuses. Furosemide as a positive control also produced similar types of skeletal abnormalities in mouse fetuses. In rabbits, azosemide did not have embryolethal or teratogenic effects even at the highest dose (6 mg/kg/ day), which caused maternal death. Treatment for a different 3-day period and then a different day during organogenesis in rats and mice showed that the sensitive period was days 15–17 of gestation with a peak on day 16 in rats, and days 12–15 with a peak on day 13 in mice.

A novel method for the carbonylation of aromatic halides by the cobalt salt catalysts such as Co(OAc)2·4H2O, CoCl2·6H2O, CoSO4·7H2O, Co(OH)2, Co(OH)3, CoO,and Co2O3 was investigated in an aqueous alkaline solution under photostimulation. These salts were found to have a catalytic activity as high as that of Co2(CO)8 under mild conditions.