Characteristics of Ultrashallow Hetero Indium–Gallium–Zinc–Oxide/Germanium Junction

In this letter, we demonstrate an n-indium-gallium-zinc-oxide (IGZO)/i-germanium (Ge) heterojunction diode with an ultrashallow junction depth of ~ 37 nm. X-ray diffraction, atomic force microscopy, and secondary ion mass spectrometry analyses are performed to precisely investigate the n-IGZO and n-IGZO/i-Ge junctions. When the junction diodes are annealed at between 400 °C and 600 °C, a very high on-current density (180-320 A/cm
²
), which is comparable to that of a Ti/i-Ge reference junction, is obtained. In particular, after the 600 °C anneal, a fairly high on/ off-current ratio (7×10
²
) is also observed.