Co-Investigator(Kenkyū-buntansha) |
KADOYA Yutaka Faculty of Engineering, Hiroshima University, Associate Professor, 工学部, 助教授 (90263730)
MIURA Michiko Faculty of Engineering, Hiroshima University, Professor, 工学部, 教授 (70291482)
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Budget Amount *help |
¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 1999: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1998: ¥1,800,000 (Direct Cost: ¥1,800,000)
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Research Abstract |
As the shot noise is one of the main noise sources in electronic devices, the suppression of a shot noise is expected for the architecture of semiconductor devices, such as a field effect transistor, a laser, and a light emitted diode (LED). Recently, the suppression of the shot noise level in current flow from the multiple tunnel junction (MTJ) was proposed, due to the coulomb charging effect at each tunnel junction. In this research, we experimentally investigated the possibility of noise suppression by using the semiconductor multiple tunnel junctions. In order to clarify the noise suppression by MTJ, we evaluated the photon number fluctuation (Fano Factor) from a LED, which is directiy connected with the MTJ. First, we prepared N×(n-GaAs / i-AlGaAs) tunnel devices by Molecular Beam Epitaxy and the wet chemical etching technique, where N is the number of barriers. When the N×(MTJ) whose resistance is by 20th much larger than the differential resistance of LED is connected with LED, we found the occurrence of the 1/N noise suppression in Fano Factor at room temperature. We also have been investigated the analysis of photon number fluctuation in LED in terms of the Langevin-equation method As a results, our experirnental results is in accordance with theoretical one, when the resistance of the multiple tunnel junction is much larger than the differential resistance of LED. Therefore, for the suppression of the shot noise, the MTJ is promising in semicbnductor devices.
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