Publications Details

Single-electron-occupation metal-oxide-semiconductor quantum dots formed from efficient poly-silicon gate layout

Carroll, Malcolm; Rochette, Sophie; Rudolph, Martin R.; Roy, A.M.; Curry, Matthew J.; Ten Eyck, Gregory A.; Manginell, Ronald P.; Wendt, J.R.; Pluym, Tammy P.; Carr, Stephen M.; Ward, Daniel R.; Lilly, Michael L.; Pioro-Ladriere, Michel

We introduce a silicon metal-oxide-semiconductor quantum dot structure that achieves dot-reservoir tunnel coupling control without a dedicated barrier gate. The elementary structure consists of two accumulation gates separated spatially by a gap, one gate accumulating a reservoir and the other a quantum dot. Control of the tunnel rate between the dot and the reservoir across the gap is demonstrated in the single electron regime by varying the reservoir accumulation gate voltage while compensating with the dot accumulation gate voltage. The method is then applied to a quantum dot connected in series to source and drain reservoirs, enabling transport down to the single electron regime. Finally, tuning of the valley splitting with the dot accumulation gate voltage is observed. This split accumulation gate structure creates silicon quantum dots of similar characteristics to other realizations but with less electrodes, in a single gate stack subtractive fabrication process that is fully compatible with silicon foundry manufacturing.