Alloyed junction Ge Esaki diodes on Si substrates realised by aspect ratio trapping technique

A Ge Esaki diode is demonstrated on Si atop a coalesced epitaxial layer of Ge grown through narrow openings in SiO2 that are used to trap threading dislocations from the lattice mismatch. Spin-on doping was used to form the n-type junction and a controlled alloyed reaction of Al and Ge forms the p-type junction. At an alloy temperature of 580°C for 1 s, the Ge-on-Si diodes were found to have a peak-to-valley current ratio of 1.1 with a peak current density of 4.1 kA/cm2.