Insulator Materials for Interface Passivation of Cu(In,Ga)Se2 Thin Films
Insulator Materials for Interface Passivation of Cu(In,Ga)Se2 Thin Films
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Cu(In,Ga)Se2 薄膜界面钝化绝缘体材料
DOI：
10.1109/jphotov.2018.2846674
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发表时间：
2018
影响因子：
3
通讯作者：
P. Salomé
中科院分区：
文献类型：
--
作者：
J. Cunha;P. Fernandes;A. Hultqvist;J. Teixeira;S. Bose;B. Vermang;S. Garud;D. Buldu;J. Gaspar;M. Edoff;J. Leitão;P. Salomé
在这项工作中，制备了金属-绝缘体-半导体结构，以研究用作 Cu(In,Ga)Se<sub>2</sub> (CIGS) 薄膜太阳能电池钝化层的不同类型的绝缘体，即氧化铝 (Al<sub>2</sub>O<sub>3</sub>)、氮化硅和氧化硅 (SiO<italic> <sub>x</sub></italic>)。所研究的叠层由 SLG/Mo/CIGS/绝缘体/Al 组成。进行拉曼散射和光致发光测量以验证绝缘体沉积对 CIGS 表面的影响。为了研究 CIGS-绝缘体界面的电气特性，进行了电容与电导和电压 (<斜体>C-G-V</斜体>) 测量，以估计固定绝缘体电荷的数量和极性 (<斜体>Q<sub>f</sub></斜体>)。界面缺陷的密度 (<斜体>D</斜体><sub>it</sub>) 通过电容与电导和频率 (<斜体>C-G-f</斜体>) 测量来估计。这项研究证明，高温 (300 °C) 下绝缘体的沉积和溅射技术的使用会导致 CIGS 表面发生表面改性。我们发现，通过改变 SiO<italic><sub>x</sub></italic> 沉积参数，绝缘体内部可能具有相反的电荷，这将允许其在不同的器件架构中使用。通过溅射沉积时，<italic>D</italic><sub>it</sub> 值较低的材料是 Al<sub>2</sub>O<sub>3</sub>。
In this work, metal–insulator–semiconductor structures were fabricated in order to study different types of insulators, namely, aluminum oxide (Al<sub>2</sub>O<sub>3</sub>), silicon nitride, and silicon oxide (SiO<italic> <sub>x</sub></italic>) to be used as passivation layers in Cu(In,Ga)Se<sub>2</sub> (CIGS) thin-film solar cells. The investigated stacks consisted of SLG/Mo/CIGS/insulator/Al. Raman scattering and photoluminescence measurements were done to verify the insulator deposition influence on the CIGS surface. In order to study the electrical properties of the CIGS–insulator interface, capacitance versus conductance and voltage (<italic>C–G–V</italic>) measurements were done to estimate the number and polarity of fixed insulator charges (<italic>Q<sub>f</sub></italic> ). The density of interface defects (<italic>D</italic><sub>it</sub>) was estimated from capacitance versus conductance and frequency (<italic>C–G–f</italic>) measurements. This study evidences that the deposition of the insulators at high temperatures (300 °C) and the use of a sputtering technique cause surface modification on the CIGS surface. We found that, by varying the SiO<italic><sub>x</sub></italic> deposition parameters, it is possible to have opposite charges inside the insulator, which would allow its use in different device architectures. The material with lower <italic>D</italic><sub>it</sub> values was Al<sub>2</sub>O<sub>3</sub> when deposited by sputtering.