|Budget Amount *help
¥1,900,000 (Direct Cost : ¥1,900,000)
Fiscal Year 1995 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1994 : ¥1,300,000 (Direct Cost : ¥1,300,000)
1.For widening the whisker growth area, pressure pulsed exchange of source gas was investigated. When the pressure change in gas exchange was about 200 Torr, process manipulation was made easy by setting pressure controll vessel before and after the reaction tube when the standard pressures were low and high, respectively. For model compounds of whiskers, silicon carbide and titanium nitride were selected.
2.Growth of SiC whiskers - Among the metals, nickel was the best for liquid-drop formation is VLS growth. A silica substrate was painted with nickel solution, and was exposed methyl-trichlorosilane-hydrogen atmosphere at 1380ﾟC.The desity of nichel nuclear was 10^8/cm^2. The numbers of pulse of 500 was satisfacory to obtain the whiskers on the wide region of substrate. The holding time per pulse of 0.75s resulted in the best distribution of whiskers. Using after-controll vessel, whiskers growed on the long substitute by applying a pressure change between -15 and -220 Torr (in gauge pressure). The results obtained by before-control vessel were rather poor.
3.Growth of TiN whiskers - The best metal which makes liquid drops in this system TiCl_4-N_2-H_2 was determined as gold, however, a preprocessing of maintaining under CVD atmosphere for above 30min at 1070ﾟC,followed by temperature lowering to growth one of 1030-1040ﾟC was necessary. The best conditions forwide area growth of whisker was determined as folowings ; concentration of TiCl_4 0.1%, holding time per pulse 0.4s, pressure range of pulse -540 - -680 Torr, and using of before-controll vessel.