Differentiating dopant and resist in device fabrication on the atomic scale

Full text: STM lithography using a hydrogen resist has been recently demonstrated to achieve atomically precise placements of single phosphorous dopants on Si(001) surfaces. This approach is currently pursued to fabricate nanoscale devices towards the quantum computer architecture proposed by Kane. So far, studying the redistribution of P dopants in the Si(001) surface has been hampered by the fact that the P dopants in the surface and remains of the hydrogen resist have close similarity in STM imaging. We demonstrate that subtle differences in the local electronic structure can be exploited for differentiating the two species in voltage-dependent imaging and Scanning Tunneling Spectroscopy. Copyright (2005) Australian Institute of Physics