CdOは,典型的な透明な導電性酸化物である. ドーパントのイオン半径と電子構造が,電荷輸送と帯域構造に及ぼす影響の体系分析
Yu Yang1, Shu Jin, Julia E Medvedeva
1Department of Chemistry, Materials Research Center, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|June 16, 2005
まとめ
イトリウムドーピングされた酸化カドミウム (CYO) の薄膜は,優れた光学透明性と伝導性を示しています. Yドーピングは,光学帯域のギャップを高め,透明な導電性酸化物でのアプリケーションのために1.2-1.3%のドーピングで最適な特性を達成します.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- 薄膜技術による技術です.
背景:
- 透明な導電性酸化物 (TCOs) は,光電子機器にとって極めて重要です.
- カドミウム酸化物 (CdO) は有望なTCO材料ですが,ドーピングによってその性質を調節することができます.
- イットリウム (Y) ドーピングは,CdOの電気的および光学的特性を修正する経路を提供します.
研究 の 目的:
- イトリウムドーピングされたCdO (CYO) 薄膜を合成し,特徴づけます.
- CdOの構造,電気,光学特性に対するYドーピングの影響を調査する.
- 実験的および理論的方法を使用して,Yドーピングの効果を他のドーパント (In, Sc) と比較する.
主な方法:
- 薄膜の成長のための金属有機化学蒸気堆積 (MOCVD).
- 段階構造と微細構造の分析のためのX線 difraktion (XRD).
- 光学伝導率と電気伝導率の測定. 光学伝導率と電気伝導率の測定. 光学伝導率と電気伝導率の測定. 光学伝導率と電気伝導力の測定.
- 電子バンド構造の計算.
主要な成果:
- 純相,多結晶CYO薄膜は,ガラスとMgO100) 基板で成功裏に成長しました.
- フィルムは,可視範囲で>80%の光学伝導率を示した.
- Yドーピングは,バンドギャップを3.27 eV (ブルスタイン-モスシフト) に拡大した.
- 最適なYドーピング (1.2-1.3%) で導電性は8,540 S/cm (ガラス) と17,800 S/cm (MgO100) であった.
- ドーパントのイオン半径と電子構造は,格子パラメータ,キャリアの移動性,ドーピング効率に大きく影響します.
結論:
- イットリウムドーピングは,CdOベースの透明な導電性酸化物の性能を向上させるのに有効です.
- この研究は,ドーピングされたCdOシステムの構造-特性関係に関する洞察を提供します.
- 実験的および理論的発見は,TCO特性を最適化するためにドーパント選択の重要性を強調しています.
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