GaAsP/Si tandem solar cells: In situ study on GaP/Si:As virtual substrate preparation
GaAsP/Si tandem solar cells: In situ study on GaP/Si:As virtual substrate preparation
复制标题
GaAsP/Si 叠层太阳能电池：GaP/Si:As 虚拟衬底制备的原位研究
DOI：
10.1016/j.solmat.2017.07.032
复制
发表时间：
2017
影响因子：
6.9
通讯作者：
T. Hannappel
中科院分区：
文献类型：
--
作者：
A. Paszuk;O. Supplie;Boram Kim;S. Brückner;M. Nandy;A. Heinisch;P. Kleinschmidt;Y. Nakano;M. Sugiyama;T. Hannappel
Realization of high efficiency III-V-on-Si solar cells requires preparation of an oxygen free Si substrate surface, which allows for subsequent antiphase domain free III-V epitaxy. For GaAsP/Si tandem cells, the impact of As on established Si processing in metal organic vapor phase epitaxy (MOVPE) is essential. Here, we study the interaction of As with vicinal Si(100) surfaces, the formation of atomically well-ordered As-modified Si(100) surfaces, and its impact on subsequently grown GaP epilayers. We apply opticalin situspectroscopy during MOVPE and show that process routes strongly affect the formation of double-layer steps on Si(100). We demonstrate that exposure to As, together with HF pre-treatment, enables processing of suitable Si(100) 2° and 6° offcut surfaces at temperatures below 820 °C. Subsequently grown GaP epilayers exhibit smooth surfaces free of antiphase disorder and distinct Laue oscillations in X-ray diffraction. Such low temperature processing, which is controllablein situ, is promising for further metamorphic GaAsP integration.
