Research on the β-Ga2O3 Power Diodes with N2O Plasma Pretreatment

This paper proposes a method that pretreating the anode surface with N2O plasma to reduce the etching damage caused by Cl-based etching. The I-V characteristics and breakdown characteristics of untreated conventional Schottky barrier diode(UT-CSBD), untreated recessed SBD(UT-RSBD), conventional SBD pretreated with N
2
O plasma(PT-CSBD) and recessed SBD pretreated with N
2
O plasma(PT-RSBD) are studied. It was found that the current density of the untreated device decreased from 797 A/cm
²
to 759 A/cm
²
after etching, while that of the device pretreated with N
2
O plasma decreased from 845 A/cm
²
to 830 A/cm
²
after etching; the change rate decreased from 4.02% to 1.78%, and the specific on-resistance(R
on,sp
) of the untreated device increased from 5.92 mΩ·cm
²
to 6.70 mΩ·cm
²
after etching, while that of the device pretreated by N
2
O plasma increased from 5.07 mΩ·cm
²
to 5.29 mΩ·cm
²
after etching; the change rate decreased from 13.18% to 4.34%, and the change rate decreased significantly. This shows that the N
2
O plasma pretreatment can inhibit the formation of defects such as oxygen vacancies caused by Cl-based etching in β-Ga
2
O
3
and reduce etching damage in Ga
2
O
3
power diodes.