The optical property improvement of GaAs via surface passivation and carriers restriction of MgO film

ABSTRACT

Surface passivation is an effective way to eliminate the surface states and to improve the optical properties of GaAs. Moreover, carriers restriction of wide bandgap materials also is a path to enhance photoluminescence. In this paper, Be-doped GaAs epilayer was growth on GaAs substrate by molecular beam epitaxy. The MgO films were deposited by atom layer deposition. It was used as not only passivation layer to eliminate surface states, but also barrier layer to restrict carriers. The carriers restriction was confirmed by photoluminescence and current-voltage characteristics of metal-insulator-semiconductor structure. As the result, the photoluminescence intensity of Be-doped GaAs with 5 nm MgO was 2.5 times higher than the bare Be-doped GaAs.

KEYWORDS:

• GaAs
• MgO
• passivation
• carriers restriction

Additional information

Funding

This work is supported by the National Natural Science Foundation of China (61474010, 61574022, 61504012, 61674021 and 11674038), the Developing Project of Science and Technology of Jilin Province (20160519007JH, 20160101255JC, 20160204074GX and 20170520117JH), The Innovation Foundation of Changchun University of Science and Technology (XJJLG-2016-11 and XJJLG-2016-14).