Effect of B and N isovalent impurities on the electronic transport of GaAs and GaP based alloys for silicon photonics and photovoltaics

在GaAs、GaP和相应的含in合金中加入同价硼或氮是在Si衬底上获得高质量的III-V半导体单片生长的唯一途径，这是向硅光子学迈出的重要一步，即在同一衬底上集成III-V光电子学和硅电子学。然而，这种合金不仅降低了与硅晶格匹配所必需的平均晶格常数，而且在这些合金的导带边缘附近诱导了N和B相关的局域态，这些局域态充当了陷阱和散射中心，从而对电子传递产生了负面影响。由于这些合金将被用于硅光子器件结构的n型接触区域，因此为了成功地按照这种方法制备硅光子器件，需要研究和理解这些内在效应的影响。此外，由于硅与III-V的极性差异，材料界面处可能出现空间电荷、交叉和反相边界，不仅影响界面本身的输运，还会影响上面含有III-V接触层的B或N的外部输运。我们建议在1.5 ~ 300 K的静水压力下进行磁输运实验，并进行垂直输运测量，以全面研究这些对电子输运的影响。本文将研究和比较在III-V和si衬底上生长的四种合金(Ga(N,As), (B,Ga)As, Ga(N，P), (B,Ga)P)，它们的导电带结构或同价杂质的性质不同。最先进的半导体样品由外部合作伙伴提供。实验结果的解释将与该领域的主要理论团体密切合作进行。

Incorporating isovalent boron or nitrogen into GaAs, GaP and corresponding In-containing alloys is the only way to obtain high-quality monolithic growth of such III-V semiconductors on Si substrates, which is a major step towards silicon photonics, i.e. the integration of III-V optoelectronics and silicon electronics on the same substrate. However, this alloying not only reduces the average lattice constant, essential for obtaining lattice-matching with silicon, but also induces, in the vicinity of the conduction band edges of these alloys, N and B related localized states which act as traps and scattering centers and thus have a negative effect on electron transport. As these alloys will be employed in the n-type contact regions of silicon photonic device structures, the impact of these intrinsic effects needs to be studied and understood in order to successfully prepare silicon photonic devices following this approach. In addition, due to the polarity difference between silicon and III-V, space charges at the interface between the materials, crossdoping, and antiphase boundaries may occur, which not only affect the transport through the interface itself, but also affects extrinsically transport in the B or N containing III-V contact layer above. We propose to perform a comprehensive study of these effects on the electronic transport by performing magnetotransport experiments under hydrostatic pressure up to 1.5 GPa in the temperature range between 1.5 and 300 K as well as vertical transport measurements. Four kind of alloy (e.g. Ga(N,As), (B,Ga)As, Ga(N,P), (B,Ga)P) grown on III-V as well as Si-substrates, which either differ with respect to the conduction band structure of the host or the character of the isovalent impurity, will be studied and compared. State-of-the-art semiconductor samples are provided by external partners. The interpretation of the experimental results will be carried out in close established cooperation with leading theoretical groups in the field.