Novel Detectors For Single Atom Doping Of Quantum Computer Devices

Devices that employ single atoms to store and manipulate information will be constructed in the near future. For example a solid state quantum computer device has been proposed that encodes information in the nuclear spin of shallow arrays of single 31P atoms (qubits) in a matrix of pure silicon. Construction of these devices presents formidable challenges. We have proposed a strategy that employs single ion implantation, with an energy of 10 to 20 keV, to load the qubits into prefabricated cells of the device that employs detector electrodes adjacent to the cells that can detect single keV ion strikes appropriate for the fabrication of shallow arrays. Our method utilises a pure silicon substrate with a very high resistivity, a thin (5 nm) SiO2 surface layer, biased electrodes applied to the surface and sensitive electronics that can detect the charge transient from single keV ion strikes. A key feature of these detectors is the ultra‐thin surface dead layer. The charge collection efficiency of these dete...