| Project/Area Number |
03650254
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
電子材料工学
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| Research Institution | RESEARCH INSTITUTE OF ELECTRONICS, SHIZUOKA UNIVERSITY |
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Principal Investigator |
KOMAGAWA Masashi SHIZUOKA UNIVERSITY・RESEARCH INSTITUTE OF ELECTRONICS・PROFESSOR, 電子工学研究所, 教授 (30022130)
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| Co-Investigator(Kenkyū-buntansha) |
HAYAKAWA Yasuhiro SHIZUOKA UNIVERSITY・RESEARCH INSTITUTE OF ELECTRONICS・RESEARCH ASSOCIATE, 電子工学研究所, 助手 (00115453)
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| Project Period (FY) |
1991 – 1992
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| Project Status |
Completed (Fiscal Year 1992)
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| Budget Amount *help |
¥2,700,000 (Direct Cost: ¥2,700,000)
Fiscal Year 1992: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1991: ¥1,700,000 (Direct Cost: ¥1,700,000)
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| Keywords | Ternary crystal / Bulk single crystal / Crystal growth / Ultrasonic vibration / Constitutional supercooling / Melt temperature fluctuation / III-V semiconductor |
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| Research Abstract |
The following main results were obtained in the research project for 2 years.
1. A crystal growth apparatus with an ultrasonic vibrator was designed and fabricated. The shape of a connector between the crucible and the vibrator was modified and as a result the output power enough for the crystal growth was obtained.
2. In order to investigate the effect of vibrations on the ternary bulk crystals, temperature fluctuation in the melt was measured by a fast Fourier transform analyser. Under vibrations, the radial temperature gradient along the melt surface decreased, but that along the depth did not change. From the comparison with the grown crystals, it is understood that the compositions in the melt near the growing interface was homogeneized by a stirring effect and consequently the constitutional supercooling reduced. This promoted the growth of single ternary bulk crystals.
3. The work of ultrasonic vibrations makes the melt to move perpendicularly for the growing interface. To compare the effect due to the moving direction of the melt on the growth of ternary crystals, the motion parallel to the interface was applied using two new methods. The one was a modified Bridgman method in which a relative motion was given between the crystal and the melt. The other was a modified Czochralski method in which the seed crystal was rotated clockwise and counter-clockwise directions alternately. Moreover, the growth technique without motion of the melt such as LPE was also used to compare with three methods. As the ternary bulk crystals were grown by the methods with the melt motion, we can conclude that the sort of melt motion was not important but the dynamic conditions were necessary to grow large bulk crystals.
The information obtained in this research will contribute the bulk crystal growth of the III-V ternary and quaternary semiconductors and also other kinds of crystals.
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