Detection of Nonradiative Recombination Centers in GaPN by Combining Two‐Wavelength Excited Photoluminescence and Time‐Resolved Photoluminescence
Detection of Nonradiative Recombination Centers in GaPN by Combining Two‐Wavelength Excited Photoluminescence and Time‐Resolved Photoluminescence
复制标题
结合双波长激发光致发光和时间分辨光致发光检测 GaPN 中的非辐射复合中心
DOI：
10.1002/pssb.202100119
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Shuhei Yagi
中科院分区：
文献类型：
--
作者：
Sanjida Ferdous;Hiroki Iwai;Norihiko Kamata;Hiroyuki Yaguchi;Shuhei Yagi
用双波长激发光致发光方法和时间分辨光致发光(TRPL)测量研究了中间带(IB)型材料GaP_(1-x)N_x()中非辐射复合(NRR)中心的存在及其影响.在77 K下，利用带隙下激发(BGE)光和带上激发(AGE)，发现光致发光峰值强度增加，这表明NRR中心的存在和从IB到导带(CB)的二次激发.根据不同BGE能量的影响，解释了NRR中心分布和NRR过程的能量图。光致发光的饱和增长归因于NRR中心的陷阱填充效应，这使得我们可以修正速率方程。对修正的单能级模型的速率方程进行了定性模拟，并结合TRPL确定的寿命对NRR参数进行了估算。在继续用速率方程分析评估NRR参数的基础上，增加了TRPL测量，提高了精度，并接近于NRR参数的确定。NRR中心的成功表征导致了IB型太阳能电池(IBSCs)的适当优化。
Presence and influence of nonradiative recombination (NRR) centers in an intermediate band (IB)‐type material, GaP1–xNx(), are studied by two‐wavelength excited photoluminescence (TWEPL) method and time‐resolved photoluminescence (TRPL) measurement at 77 K. With the use of below‐gap excitation (BGE) light in addition to an above‐gap excitation (AGE), the PL peak intensity is found to increase which indicates the presence of NRR centers and a secondary excitation from the IB to conduction band (CB). Depending on the effect of different BGE energies, an energy diagram on the distribution of NRR centers and NRR process is interpreted. The saturation of PL increase is attributed to the trap‐filling effect in NRR centers, which allows us to modify the rate equation. The NRR parameters are evaluated by a qualitative simulation of the modified rate equations of one‐level model together with the lifetime determined by TRPL. In continuation of evaluating NRR parameters by rate equation analysis, the addition of TRPL measurement improves accuracy and approaches the determination of NRR parameters. A successful characterization of NRR centers leads to a proper optimization of IB‐type solar cells (IBSCs).