Mechanical writing of n-type conductive layers on the SrTiO(3) surface in nanoscale

The fabrication and control of the conductive surface and interface on insulating SrTiO(3) bulk provide a pathway for oxide electronics. The controllable manipulation of local doping concentration in semiconductors is an important step for nano-electronics. Here we show that conductive patterns can be written on bare SrTiO(3) surface by controllable doping in nanoscale using the mechanical interactions of atomic force microscopy tip without applying external electric field. The conductivity of the layer is n-type, oxygen sensitive, and can be effectively tuned by the gate voltage. Hence, our findings have potential applications in oxide nano-circuits and oxygen sensors.