The Melbourne Node

1
The Melbourne Node
2
The Melbourne Node
3
The Melbourne Node
Node Team Leader Steven Prawer
Test structures created by single ion implantation
Atom Lithography and AFM measurement of test
structures
Theory of Coherence and Decoherence
4
Key Personnel

• Students
• Paul Otsuka
• MatthewNorman
• Elizabeth Trajkov
• Brett Johnson
• Amelia Liu
• Leigh Morpheth
• David Hoxley
• Andrew Bettiol
• Deborah Beckman
• Jacinta Den Besten
• Kristie Kerr
• Louie Kostidis
• Poo Fun Lai
• Jamie Laird
• Kin Kiong Lee

• Geoff Leech DeborahLouGreig
• Ming Sheng Liu
• Glenn Moloney
• Julius Orwa
• Arthur Sakalleiou
• Russell Walker
• Cameron Wellard

• Academic Staff
• David Jamieson
• Steven Prawer
• Lloyd Hollenberg
• Postdoctoral Fellows
• Jeff McCallum
• Paul Spizzirri
• Igor Adrienko
• 2
• Infrastructure
• Alberto Cimmino
• Roland Szymanski
• William Belcher
• Eliecer Para

5
Existing Infrastructure

• NEC 5U Pelletron accelerator with RIEF funded
  upgrade to make it one of the brightest
  accelerators in the world for nuclear microprobe
  operation (2,000,000)
• Two MeV ion microprobe beam lines and associated
  instrumentation (1,000,000 each)
• Dilor confocal Raman spectrometer (500,000)
• Joel UHV AFM (700,000)
• Distributed computer network (100,000).
• Pulsed Laser Deposition System (1,000,000)
• This combination of instruments is unique
  worldwide for one research Centre!

6
The Science

• Creation of an array of phosphorous ions ina Si m

7
The Melbourne Pelletron Accelerator

• Installed in 1975 for nuclear physics
  experiments.
• National Electrostatics Corp. 5U Pelletron.
• Now full time for nuclear microprobe operation.
• Will be state-of-the-art following RIEFP upgrade
• Capable of delivering a single ion into an area
  0.25 mm in diameter

Accelerator
Specimen Chamber
8
JEOL Variable Temperature UHV AFM/STM

• Imaging RT-800K
• Cantilever based AFM
• STM imaging with tip or AFM cantilever
• All imaging modes available
• In situ evaporation source.
• In situ ion sputtering.

9
Atom Lithography Key Imaging Fabrication
Technology
10
Programmed Lithography for nanofabrication
100 x 100 nm
1 atom deep, 10 atoms wide
Alberto Cimmino leaves his mark
11
AFM imaging of surfaces
Atomic Force Microscope Image of Si 7 x 7 surface
reconstruction. Each dot is a single Si atom.
12
Test structures created by single ion implantation

• The basic idea
• Previous work
• Potential problems and solutions

13
Single Ion Implantation Fabrication Strategy
Etch latent damage metallise
Read-out state of qubits
MeV 31P implant
Resist layer
Si substrate
14
MeV ion etch pits in track detector

• Single MeV heavy ions are used to produce latent
  damage in plastic
• Etching in NaOH develops this damage to produce
  pits
• Light ions produce smaller pits

3. Etch
2. Latent damage
1. Irradiate
From B.E. Fischer, Nucl. Instr. Meth. B54 (1991)
401.
15
Single ion tracks
Depth

• Latent damage from single-ion irradiation of a
  crystal (Bi2Sr2CaCuOx)
• Beam 230 MeV Au
• Lighter ions produce narrower tracks!

1 mm
3 mm
5 mm
7.5 mm
3 nm
From Huang and Sasaki, Influence of ion velocity
on damage efficiency in the single ion target
irradiation system Au-Bi2Sr2CaCu2Ox Phys Rev B
59, p3862
16
Project Management - A distributed system
Director Clark
Deputy Director Milburn
Theory/Modelling
Array fabrication
Readout
SET Dzurak
Magnetic Resonance (LANL)
Quantum Optics Rubeinstein-Dunlop
Single Ion Implantation Jamieson
Atom Lithography Prawer
Silicon MBE Simmons
17
Potential Problems