Minority Carrier Transport in Heavily Doped GaAs

高掺杂砷化镓中的少数载流子输运控制着异质结双极晶体管和太阳能电池等双极器件的性能。众所周知，所谓的重掺杂效应（即重杂质掺杂对能带结构、载流子散射和重组的影响）会深刻影响硅器件的行为。重杂质掺杂对砷化镓光学性能的影响已被广泛研究，但评估其对器件电性能影响的实验工作几乎没有。本研究的目的是通过实验表征GaAs中平衡np积和少数载流子迁移率与多数载流子浓度的关系。该研究将增加我们对重掺杂GaAs的能带结构和少数载流子散射机制的认识。它将提供测试现有理论模型的数据和对设备设计至关重要的信息。对与重杂质设计相关的能带结构变化的理解也可能允许利用由重杂质掺杂自然产生的异质结的新器件选择。

Minority carrier transport in heavily doped GaAs controls the performance of bipolar devices such as heterojunction bipolar transistors and solar cells. So-called heavy doping effects (that is, the influence of heavy impurity doping on the band structure, carrier scattering, and recombination) are well-known to profoundly influence the behavior of silicon devices. The influence of heavy impurity doping on the optical properties of GaAs has been extensively studied, but experimental work to assess its influence on the electrical properties of devices is virtually nonexistent. The objective of this research is to experimentally characterize the equilibrium np product and the minority carrier mobility versus majority carrier concentration in GaAs. The research will increase our knowledge of the band structure and minority carrier scattering mechanisms in heavily doped GaAs. It will provide data to test existing theoretical models and information that is essential for device design. An understanding of the band structure changes associated with heavy impurity design may also permit new device options which exploit the heterojunctions that occur naturally as a result of heavy impurity doping.