Fabrication of Mg₂Si pn-junction photodiode with shallow mesa-structure and ring electrode

Abstract

We fabricated Mg2Si pn-juncion photodiodes with a shallow mesa structure and a ring electrode using a conventional photolithography process and investigated their electrical and optical character. Dark current densities of about 0.18 and 9 × 10-4 A/cm 2 were obtained at room temperature and 100 K under the reverse bias at-3 V. Photoresponse below about 2.1 μm was observed in the shallow mesa-type PDs at room temperature operation. The photosensitivity at 1.31 μm was determined about 22 mA/W and 42 mA/W for the bias voltage at 0 and-0.1 V, respectively.