Enhanced hole concentration and improved surface morphology for nonpolar a-plane p-type AlGaN/GaN superlattices grown with indium-surfactant. (June 2019)

• Record Type: Journal Article
• Authors: Fan, Aijie; Zhang, Xiong; Wu, Zili; Zhao, Jianguo; Chen, Shuai; Chen, Hu; Nasir, Abbas; Cui, Yiping
• Is Part Of: Superlattices and microstructures. Volume 130(2019)
• Page Start: 396
• Page End: 400
• Publication Date: 2019-06
• Subjects: Nonpolar a-plane AlGaN/GaN superlattices -- Mg-delta-doping -- Indium surfactant -- Surface morphology -- Hole concentration; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2019.05.012
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: The nonpolar a -plane Mg-delta-doped Al0.6 Ga0.4 N/GaN superlattices (SLs) with enhanced hole concentration were successfully grown by using indium (In)-surfactant with metal organic chemical vapor deposition (MOCVD) technology. The effect of In-surfactant on the characteristics of the nonpolar a -plane Mg-doped AlGaN/GaN SLs were studied with scanning electron microscopy, atomic force microscopy, X-ray diffraction, and Hall effect measurements. It was found that the surface morphology was improved evidently and the hole concentration was enhanced effectively with the use of In-surfactant. In fact, a root-mean-square value as small as 0.8 nm and a hole concentration as high as 5.1 × 10 17 cm -3 were achieved by carefully optimizing the TMIn mole flow rate in the MOCVD growth process. Moreover, it was inferred that the enhancement in hole concentration was due to the significant increase in the Mg incorporation efficiency and the decrease in the self-compensation effect induced by the proper usage of In-surfactant. Highlights: The nonpolar a -plane Mg-delta-doped Al0.6 Ga0.4 N/GaN superlattices (SLs) were grown by using indium (In)-surfactant with metal organic chemical vapor deposition technology. A hole concentration of 5.1 × 10 17 cm -3 and a hole mobility of 4.7 cm 2 /V s of nonpolar a -plane p-type Al0.6 Ga0.4 N/GaN superlattices was achieved with a TMIn flow rate of 1.94 μmol/min. A root-mean-square value as small as 0.8 nm of nonpolar a -plane p-Al0.6 Ga0.4 N/GaN superlattices was achieved by carefully optimizing the TMIn mole flow rate in the MOCVD growth process.