Ultra shallow sidewall GaAs tunnel junctions implemented with molecular layer epitaxy

Low-temperature (290/spl deg/C) area selective regrowth by molecular layer epitaxy (MLE) was applied for the fabrication of ultra shallow sidewall GaAs tunnel junctions with the junction depth of 50 nm at 100 /spl mu/m long strip. Fabricated tunnel junctions have shown the record peak current density up to 35000 A/cm/sup 2/. It is shown that the tunnel junction characteristics are seriously dependent on the sidewall orientation and the regrown interface quality, which is controlled by the surface treatment under AsH/sub 3/ just prior to regrowth. MLE with the low-temperature area selective regrowth process is one of the most promising methods for the fabrication of ultra short channel devices.