Sun G, Soref R A, Cheng H H
Department of Physics, University of Massachusetts Boston, Boston, MA 02125, USA.
Opt Express. 2010 Sep 13;18(19):19957-65. doi: 10.1364/OE.18.019957.
This paper presents modeling and simulation of a silicon-based group IV semiconductor injection laser diode in which the active region has a multiple quantum well structure formed with Ge(0.9)Sn(0.1) quantum wells separated by Ge(0.75)Si(0.1)Sn(0.15) barriers. These alloy compositions were chosen to satisfy three conditions simultaneously: a direct band gap for Ge(0.9)Sn(0.1), type-I band alignment between Ge(0.9)Sn(0.1) and Ge(0.75)Si(0.1)Sn(0.15,) and a lattice match between wells and barriers. This match ensures that the entire structure can be grown strain free upon a relaxed Ge(0.75)Si(0.1)Sn(0.15) buffer on a silicon substrate - a CMOS compatible process. Detailed analysis is performed for the type I band offsets, carrier lifetime, optical confinement, and modal gain. The carrier lifetime is found to be dominated by the spontaneous radiative process rather than the Auger process. The modal gain has a rather sensitive dependence on the number of quantum wells in the active region. The proposed laser is predicted to operate at 2.3 μm in the mid infrared at room temperature.
本文介绍了一种基于硅的IV族半导体注入激光二极管的建模与仿真，其中有源区具有多量子阱结构，由Ge(0.9)Sn(0.1)量子阱组成，被Ge(0.75)Si(0.1)Sn(0.15)势垒隔开。选择这些合金成分是为了同时满足三个条件：Ge(0.9)Sn(0.1)的直接带隙、Ge(0.9)Sn(0.1)与Ge(0.75)Si(0.1)Sn(0.15)之间的I型能带排列以及阱与势垒之间的晶格匹配。这种匹配确保了整个结构可以在硅衬底上的弛豫Ge(0.75)Si(0.1)Sn(0.15)缓冲层上无应变生长——这是一种与CMOS兼容的工艺。对I型能带偏移、载流子寿命、光限制和模式增益进行了详细分析。发现载流子寿命主要由自发辐射过程而非俄歇过程主导。模式增益对有源区量子阱的数量有相当敏感的依赖性。预计所提出的激光器在室温下的中红外波段以2.3μm波长工作。
