Author(s): Shi, YM (Shi, Yiming); Meng, JH (Meng, Junhua); Chen, JR (Chen, Jingren); Wu, R (Wu, Rui); Zhang, LS (Zhang, Lisheng); Jiang, J (Jiang, Ji); Deng, JX (Deng, Jinxiang); Yin, ZG (Yin, Zhigang); Zhang, XW (Zhang, Xingwang)

Source: JOURNAL OF ALLOYS AND COMPOUNDS Volume: 974  Article Number: 172946  DOI: 10.1016/j.jallcom.2023.172946  Published: FEB 15 2024 

Abstract: As a common impurity, H plays a role in tuning the electrical properties of beta-Ga2O3 and has attracted immense interest. Despite years of investigations, the influence of H-doping on electrical properties is not always clear due to the lack of comprehensive characterization on both micro- and macro scale. In this work, we investigate the effects of the H-plasma treatment on the electrical properties of beta-Ga2O3 films by combining several techniques, from macroscale Hall and photoluminescence measurements to microscale conductive atomic force microscopy (CAFM) and Kelvin probe force microscopy (KPFM). The incorporation of H in beta-Ga2O3 not only introduces shallow donor states such as H-i, but also passivates V-Ga defects by forming the V-Ga-4H complex. As a result, both the carrier concentration and mobility of H-doped beta-Ga2O3 film are significantly increased, corresponding to an enhancement of conductivity by four orders of magnitude in comparison with the intrinsic one. These results correlate well with the local conductivity and surface potential mappings obtained from CAFM and KPFM. Moreover, we found that the work function of beta-Ga2O3 thin films can also be tuned by the H-plasma treatment.

Accession Number: WOS:001127925300001

ISSN: 0925-8388

eISSN: 1873-4669