Fabrication of p-Si/β-FeSi₂/n-Si Double-Heterostructure Light-Emitting Diode by Molecular Beam Epitaxy

Abstract

We have fabricated p-Si/β-FeSi 2 film/n-Si double-heterstructure (DH) light-emitting diodes (LEDs) on Si(111) substrates by molecular beam epitaxy (MBE). It was found that both the thickness of an undoped Si overlayer and subsequent annealing temperature were key parameters in preventing the aggregation of the β-FeSi 2 film and the successful formation of a Si/β-FeSi 2 film/Si DH LED on Si(111). A 1.6 µm electroluminescence (EL) was realized at room temperature (RT) at a current density higher than 78 A/cm 2 by increasing the thickness of the β-FeSi 2 active region from 90 nm to 250 nm, suggesting that there exist numerous defects at Si/β-FeSi 2 heterointerfaces.