Author:
Bai Min ,Xuan Rong-Xi ,Song Jian-Jun ,Zhang He-Ming ,Hu Hui-Yong ,Shu Bin ,
Abstract
Indirect bandgap Ge can be turned to a direct bandgap semiconductor by the alloy-modified technique, which can be applied to advanced photonic devices and electronic devices. Based on 8 bands Kronig-Penny Hamilton, this paper focuses on the physical parameters of direct bandgap Ge1-xSnx, such as conduction band effective density of states, valence band effective density of states and the intrinsic carrier concentration, and aims to provide valuable references for understanding the direct bandgap modified Ge materials and device physics as well as their applications. Results show that: conduction band effective density of states in direct bandgap Ge1-xSnx alloy decreases obviously with increasing Sn fraction, while its valence band effective density of states almost does not change with increasing Sn fraction. Compared with bulk Ge, the conduction band effective density of states and valence band effective density of states in direct bandgap Ge1-xSnx alloy are lower by two and one orders of magnitude respectively; the intrinsic carrier concentration in direct bandgap Ge1-xSnx alloy increases with increasing Sn fraction, and its value is an order of magnitude higher than that of bulk Ge.
Publisher
Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences
Subject
General Physics and Astronomy
Reference15 articles.
1. Michael O, Konrad K, Tzanimir A, Gregor M 2014 IEEE Photon. Technol. Lett. 26 187
2. Zhang D L, Xue C, Cheng B, Su S J, Liu Z, Zhang X, Zhang G Z, Li C B, Wang Q M 2013 Appl. Phys. Lett. 102 141111
3. Tseng H H, Li H, Mashanov V, Yang Y J, Cheng H H, Chang G E, Soref R A, Sun G G 2013 Appl. Phys. Lett. 103 231907
4. Soref R A, Sun G, Cheng H H 2012 J. Appl. Phys. 111 123113
5. Tonkikh A A, Eisenschmidt C, Talalaev V G, Zakharov N D, Schilling J, Schmidt G, Werner P 2013 Appl. Phys. Lett. 103 032106