Effects of buffer layer preparation and Bi concentration on InGaAsBi epilayers grown by gas source molecular beam epitaxy

• Published in: Semiconductor science and technology Vol. 30; no. 12; pp. 125001 - 125006
• Main Authors: Zhou, Shuxing, Qi, Ming, Ai, Likun, Xu, Anhuai, Wang, Shumin
• Format: Journal Article
• Language: English
• Published: IOP Publishing 20.10.2015
• Subjects: dilute bismide; InGaAsBi; molecular beam epitaxy
• ISSN: 0268-1242; 1361-6641; 1361-6641
• DOI: 10.1088/0268-1242/30/12/125001

The effect of using an In0.53Ga0.47As buffer layer on the crystalline quality of InGaAsBi epilayer with Bi concentration up to 3.1% grown by gas source molecular beam epitaxy was investigated. It is found that use of the buffer layer has a dramatic effect on the improvement of surface morphology, structural, electrical and optical properties of InGaAsBi epilayers. Bi incorporation in InGaAs up to a concentration of 3.1% causes no degradation of the electron mobility and induces p-type carriers that compensate the background n-type carriers resulting in mobility enhancement with increasing Bi concentration. With the buffer layer preparation, a maximum electron mobility of 5550 cm2 V-1 s-1 at room temperature is demonstrated in InGaAsBi with xBi = 3.1%, which is the highest value reported in InGaAsBi with xBi > 2.5%.