High hole concentration in nonpolar a-plane p-AlGaN films with Mg-delta doping technique. (September 2017)

• Record Type: Journal Article
• Authors: Wu, Zili; Zhang, Xiong; Dai, Qian; Zhao, Jianguo; Fan, Aijie; Wang, Shuchang; Cui, Yiping
• Is Part Of: Superlattices and microstructures. Volume 109(2017)
• Page Start: 880
• Page End: 885
• Publication Date: 2017-09
• Subjects: MOCVD -- Nonpolar a-plane -- p-AlGaN -- Mg-delta-doping -- Mg incorporation; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2017.06.008
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: The Mg-delta-doping technique was employed in the epitaxial growth of the nonpolar a -plane p-AlGaN films on semi-polar r -plane sapphire substrates by metal organic chemical vapor deposition (MOCVD). The structural, morphological, and electrical properties of the nonpolar a -plane p-AlGaN epi-layers were characterized with secondary ion mass spectroscopy (SIMS), high-resolution X-ray diffraction (HR-XRD), atomic force microscopy (AFM), and Hall effect measurement, respectively. The characterization results demonstrate that the crystalline quality, the surface morphology, and the efficiency of Mg incorporation in the nonpolar a -plane p-AlGaN films could be improved significantly by optimizing the pulse time of Cp2 Mg mass flow in the Mg-delta-doping process. In fact, a hole concentration as high as 1.4 × 10 18 cm −3 under an average Mg incorporation density of ∼1 × 10 19 cm −3 was achieved. Highlights: The Mg-delta-doped nonpolar a -plane p-AlGaN epi-layers were successfully grown. A hole concentration as high as 1.4 × 10 18 cm −3 was achieved. A root mean square as small as 1.17 nm was obtained in this study. Secondary ion mass spectroscopy was used to investigate the Mg incorporation.