提取带隙能量和混合相多晶半导体的组成;一种可能的替代方法
1Department of Chemistry, University College London, 20 Gordon St, London, WC1E 6BT, UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND.
概括
确定半导体带间隙能量 (Eg) 已被简化. 使用吸收率的第二导数的新方法消除了对混合相材料适用的Tauc指数的需要.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 频谱学是一种光谱学.
背景情况:
- 光学带间隙能量 (Eg) 对于半导体应用至关重要.
- 陶克图分析是标准的,但需要知道陶克指数 (n),限制其用于混合相材料的使用.
研究的目的:
- 开发一种方法来确定混合相半导体的带隙能量 (Eg),而无需先前了解Tauc指数 (n).
- 调查吸收率导数用于相位组合分析和频段间隙测定的适用性.
主要方法:
- 测量了不同组成的混合相TiO2 (anatase和rutile) 的UV-Vis吸收.
- 对吸收率的第一个 (dA/dλ) 和第二个 (d2A/dλ2) 导数对波长的分析.
- 与X射线衍射 (XRD) 分析相位组成的比较.
主要成果:
- 吸收率的第一个导数 (dA/dλ) 与相组合相关,类似于XRD.
- 吸收率的第二导数 (d2A/dλ2) 的正峰值提供了一个稳定的带隙值 (<0.05 eV转移),无论TiO2相组合如何.
- 该方法给出了ZnO和C3N4.4的可比带隙能量.
结论:
- 吸收率的第二导数是确定半导体中带隙能量 (Eg) 的可靠方法,包括混合相材料.
- 这种方法避免了对塔克指数 (n) 的预先了解的需要,简化了分析.
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