Quantum Information Processing, Vol. 3, Nos. 1–5, October 2004 (© 2004)
Quantum Computer Development with Single Ion
S. J. Park,
J. A. Liddle,
I. W. Rangelow,
F. I. Allen,
D. H. Schneider,
and T. Schenkel
Received February 9, 2004; accepted March 15, 2004
Spins of single donor atoms are attractive candidates for large scale quantum
information processing in silicon. Formation of devices with a few qubits is cru-
cial for validation of basic ideas and development of a scalable architecture. We
describe our development of a single ion implantation technique for placement
of single atoms into device structures. Collimated highly charged ion beams are
aligned with a scanning probe microscope. Enhanced secondary electron emission
due to high ion charge states (e.g.,
) allows efﬁcient detec-
tion of single ion impacts. Studies of electrical activation of low dose, low energy
P in silicon show a drastic effect of dopant segregation to the
/Si interface, while Si
P segregation. We discuss resolution
limiting factors in ion placement, and process challenges for integration of single
atom arrays with control gates and single electron transistors.
KEY WORDS: Electron emission; single electron devices; Coulomb blockade;
ion doping; scanning probe; quantum computation.
PACS: 03.67.Lx, 34.50.Dy, 85.35.Gv, 73.23, 61.72, 86.40.py, 07.79.−v.
Several promising proposals for implementation of large scale quantum
information processing devices in solids are based on the manipulation
E. O. Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. E-mail:
Institute of Microstructure Technologies and Analytics, University of Kassel, 34109 Kassel,
Department of Electrical Engineering and Computer Science, University of California,
Berkeley, CA 94720, USA.
Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
1570-0755/04/1000-0233/0 © 2004 Springer Science+Business Media, Inc.