無機半導体の異常な可塑性 暗闇の中で
Yu Oshima1, Atsutomo Nakamura2, Katsuyuki Matsunaga2,3
1Department of Materials Physics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
まとめ
亜鉛硫化物 (ZnS) のような無機半導体は,光の下での脆い振る舞いとは異なり,完全な暗闇で変形すると驚くべき可塑性を示します. この暗闇による可塑性は 素材の光学帯域の隙間を 大きく変化させます
科学分野:
- 材料科学
- 固体物理学
- 半導体に関する研究
背景:
- 無機半導体は通常,脆い故障モードを示します.
- 光などの外部刺激が半導体の機械的性質に及ぼす影響は完全に理解されていません.
- これまでの研究では 半導体変形における暗さの役割について 詳しく調べられていませんでした
研究 の 目的:
- 異なった光条件下で無機半導体の機械的振る舞いを調査する.
- 無機半導体で可塑性を誘導できるかどうかを判断する.
- 硫化亜鉛 (ZnS) の変形と光学特性に対する暗闇の影響を調査する.
主な方法:
- 亜鉛硫化物 (ZnS) の結晶で室温変形試験を実施した.
- 実験は,完全な暗闇を含む様々な光の被曝の制御された条件下で実施された.
- 機械的変形と光学バンドギャップの測定を分析した.
主要な成果:
- ZnS結晶は,光照射で変形するとすぐに破裂する.
- 完全な暗闇では,ZnS結晶は,最大45%のストレスの高い可塑性変形を示した.
- 変形したZnS結晶は光学帯域の隙間がはっきりと減少した.
結論:
- ZnSの変位は完全な暗闇で移動し,プラスチックの変形を可能にします.
- 観察された可塑性は,無機半導体は本質的に脆くないことを示唆しています.
- 変位の倍数は,結晶全体の光学帯域の隙間に影響します.
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