Optical, electronic and visible-range photo-electronic properties of boron carbide-indole films
Optical, electronic and visible-range photo-electronic properties of boron carbide-indole films
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碳化硼吲哚薄膜的光学、电子和可见光光电特性
DOI：
10.1088/1361-6463/ab8e7e
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
J. Kelber
中科院分区：
文献类型：
--
作者：
A. Oyelade;A. Osonkie;A. Yost;N. Benker;P. Dowben;J. Kelber
采用等离子体增强化学气相沉积（PECVD）技术，以邻二碳十硼烷（orthocarborane）和吲哚（indole）为前驱物，制备了芳香族半导体碳化硼薄膜。X射线光电子能谱和椭圆偏振光谱表明，该薄膜由完整的吲哚部分键合到正碳硼烷二十面体上的B位点。的椭圆偏振测量，PECVD氢化碳化硼合金与吲哚部分，表明间接和直接带隙的1.6 eV和3.5 eV，分别与密度泛函理论集群计算的良好协议。这些计算还表明，附近的价带最大值和导带最小值的状态与吲哚和碳硼烷部分，分别。在n型硅二极管上，掺吲哚的PECVD氢化碳化硼的电流-电压（I（V））曲线表明，在零偏压下有光电流，开路电压为1V。在光照下，第四象限的电导率和电压在最大功率点分别为1.66 μA和0.69V。频率和偏置相关的电容与电压（C（V））的数据产生的平均载流子寿命从2.5 ms到1.5 ms，分别在低和高偏置，在10 kHz，但下降到0.5 ms，独立于偏置电压，在100 kHz。
Semiconducting aromatic boron carbide films have been formed by plasma enhanced chemical vapor deposition (PECVD) from closo-1,2-dicarbadodecarborane (orthocarborane) and indole precursors. X-ray photoemission and ellipsometry indicate that the films consist of intact indole moieties bonded to the B sites on orthocarborane icosahedra. The ellipsometry measurements, of the PECVD hydrogenated boron carbide alloyed with indole moieties, indicate indirect and direct band gaps of 1.6 eV and 3.5 eV, respectively, in good agreement with density functional theory cluster calculations. These calculations also indicate that states near the valence band maximum and conduction band minimum are associated with indole and carborane moieties, respectively. The current versus voltage (I(V)) curves, of PECVD hydrogenated boron carbide alloyed with indole moieties to n-type silicon diodes, indicate a photocurrent at zero bias, with an appreciable open-circuit voltage of 1 V. The 4th quadrant conductivity and voltage, at the maximum power point, were 1.66 μA and 0.69 V respectively, under illumination. The frequency- and bias-dependent capacitance versus voltage (C(V)) data yield mean carrier lifetimes from 2.5 ms to 1.5 ms at low and high bias, respectively at 10 kHz, but falling to 0.5 ms, independent of bias voltage, at 100 kHz.