| Budget Amount *help |
¥8,700,000 (Direct Cost: ¥8,700,000)
Fiscal Year 1986: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1985: ¥7,000,000 (Direct Cost: ¥7,000,000)
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| Research Abstract |
The Lang's method is the most popular and widely used technique of transmission X-ray topography. However, characteristic X-ray is used in this technique and therefore one has to prepare a thin specimen to get clear topographs especially for materials with heavy atoms.
In the present study, we planned to use strong and hard white X-rays emitted from a high power X-ray generator in Hokkaido University. First of all, we tried to produce a specially designed electron gun for a fine focussing X-ray source, since the size of source shoud be as small as possible in the topography using white X-rays. The newly designed gun has double Wehnelt covers, inner and outer, which are insulated each other, the bias voltage being applied independently. The distance between the covers as well as between the target and covers can be adjusted without difficulty. After repeating examinations to minimize the focussing size many times over, we finally obtained a minimum size of 0.08mmX0.90mm, excluding subsidiary focussed intensities. Next, the transmission topographs were taken for thick single crystal plates with heavy atoms, such as Ge, Zn, Cu, Fe, GaAs, InP, CdTe etc,, by using hard and strong white X-ray emitted from the above stated brilliant source. The geometry of X-ray optics was critically studied on the basis of the image resolution and moreover filters with optimum thicknesses for various materials were searched. It was successfully recognized that the white X-ray topograph taken for thick specimens possesses high enough quality, as well as the Lang topographs so far taken for thin specimens.
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