Publications
 
Si and SiGe Publications
V. Nyugen, B. Redlich, D.J. Paul, J. Freeman, S.A. Lynch, C.R. Pidgeon and B.N. Murdin, "Pump-probe measurement of impurity state lifetimes in silicon" Applied Physics Letters (Submitted for publication) A. De Rossi, M. Carras and D.J. Paul, "Low-loss surface-mode waveguides for terahertz Si/SiGe quantum cascade lasers" IEEE Journal of Quantum Electronics (Submitted for publication) S.A. Lynch, D.J. Paul, P. Townsend, G. Matmon, Z. Suet, R.W. Kelsall, Z. Ikonic, P. Harrison, J. Zhang, D.J. Norris, A.G. Cullis, C.R. Pidgeon, P. Murzyn, B.N. Murdin, M. Bain, H.S. Gamble, M. Zhao and W.-X. Ni, "Towards silicon-based lasers for terahertz sources" IEEE Journal of Selected Topics in Quantum Electronics (Accepted for publication) T. Ferrus, R. George, N. Lumpkin, D.J. Paul and M. Pepper, "Activation mechanisms in sodium-doped MOSFETs" Phys. Rev. B (Submitted for publication) T. Ferrus, R. George, C.H.W. Barnes, N. Lumpkin, D.J. Paul and M. Pepper, "Evidence for multiple impurity bands in sodium-doped silicon MOSFETs" Physical Review B 73, 041304 Rapid (2006) C.R. Pidgeon, P.J. Phillips, D. Carder, B.N. Murdin, T. Fromherz, D.J. Paul, W.-X. Ni and M. Zhao, "Pump-probe measurement of lifetime engineering in SiGe quantum wells below the optical phonon energy" Semiconductor Science and Technology 20, ppL50-L52 (2005) R.W. Kelsall, Z. Ikonic, C.R. Pidgeon, P.J. Philips, P. Harrison, S.A. Lynch, P. Townsend, D.J. Paul, S.L. Liew, D.J. Norris and A.G. Cullis, "Intersubband lifetimes in p-Si/SiGe terahertz quantum cascade heterostructures" Physical Review B 71, 115326 (2005) J. Zhang, X.B. Li, J.H. Neave, D.J. Norris, A.G. Cullis, S. Lynch, P. Townsend, D.J. Paul and P.F. Fewster, "SiGe quantum cascade structures for light emitting devices" Journal of Crystal Growth 278, pp488-494 (2005) I. Shlimak, V. Ginodman, A.B. Gerber, A. Milner, K.J. Friedland and D.J. Paul, "Transverse 'resistance overshoot' in a Si/SiGe two-dimensional electron gas in the quantum Hall effect regime" Europhysics Letters 69, pp997-102 (2005) D.J. Paul "Si/SiGe quantum cascade emitters" in The Silicon Heterostructure Handbook: Materials, Fabrication, Devices, Circuits and Applications of SiGe and Si Strained-Layer Epitaxy (Editor J.D. Cressler) Chapter 7.6 (2005) S.A. Lynch, P. Townsend, G. Matmon, D.J. Paul, Z. Ikonic, R.W. Kelsall, P. Harrison, D.J. Norris, A.G. Cullis, and D.D. Arnone, “Temperature dependence of terahertz optical transitions from boron and phosphorus dopant impurities in silicon” Applied Physics Letters 87, 101114 (2005) M. Dragosavac, D.J. Paul, M. Pepper, A.B. Fowler and D.A. Buchanan, "Effective electron mass in ultra-thin gate-oxide silicon MOSFET inversion layers" Semiconductor Science and Technology 20, pp664-667 (2005) G. Nicholas, T.J. Grasby, E.H.C. Parker, T.E. Whall, D.J. Paul, A.G.R. Evans and H. von Känel, "Investigation of the injection velocity of holes in strained-Si p-MOSFETs" Semiconductor Science and Technology 20, ppL20-L22 (2005) D.J. Paul, M. Temple, S.H. Olsen, A.G. O'Neill, Y.T. Tang, A.M. Waite, C. Cerrina, A.G. R. Evans, X. Li, J. Zhang, D.J. Norris and A.G. Cullis, "Strained-Si n-MOS surface channel and buried Si0.7Ge0.3 compressively strained p-MOS fabricated in a 0.25 µm heterostructure CMOS process" Materials Science in Semiconductor Processing 8(1-3), pp343-346 (2005) R.W. Kelsall, Z. Ikonic, P. Harrison, S.A. Lynch, P. Townsend, D.J. Paul, D.J. Norris, S.L. Liew, A.G. Cullis, X. Li, J. Zhang, M. Bain and H.S. Gamble, "Optical cavities for Si/SiGe terahertz quantum cascade emitters" Optical Materials 27, pp851-854 (2005) X.B. Li, J.H. Neave, D.J. Norris, A.G. Cullis, D.J. Paul, R.W. Kelsall and J. Zhang, "Growth and structural characterisation of Si/SiGe heterostructures for optoelectronic applications" Optical Materials 27, pp855-858 (2005) D.J. Paul, "Group IV Semiconductors, Si/SiGe" in Encyclopedia of Modern Optics, Elsevier pp364-372 (2005) E. Kasper and D.J. Paul, "Silicon Quantum Integrated Circuits" Springer-Verlag, Berlin-Heidelberg (2005) D.J. Paul, "Si/SiGe heterostructures: from material and physics to devices and circuits" Semiconductor Science and Technology 19, ppR75-R108 (2004) S.H. Olsen, A.G. O'Neill, S. Chattopadhyay, L.S. Driscoll, K.S.K. Kwa, D.J. Norris, A.G. Cullis and D.J. Paul, "Study of single and dual-channel designs for high performance strained-Si/SiGe n-MOSFETs" IEEE Transactions of Electron Devices, 51(7), pp1245-1253 (2004) R. Bates, S.A. Lynch, D.J. Paul, Z. Ikonic, R.W. Kelsall, P. Harrison, D.J. Norris, S.L. Liew, A.G. Cullis, W. Tribe and D.D. Arnone, "Diagonal intersubband transitions in Si/SiGe quantum cascade emitters" Applied Physics Letters 83(20), pp4092-4094 (2003) A. Lewalle, M. Pepper, C.J.B. Ford, D.J. Paul and G. Redmond, “The masking by weak localisation of metallic behaviour in a two-dimensional system in strong parallel magnetic fields” Physical Review B 69, art. no. 075316 pp1-6 (2004) S. Olsen, L. Driscoll, K. Kwa, S. Chattopadhyay, A. O'Neill, A. Waite, Y. Tang, A. Evans, D.J. Norris, A.G. Cullis, D.J. Paul and D.J. Robbins "High performance strained Si/SiGe nMOSFETs using a novel CMOS architecture" IEEE Transactions on Electron Devices 50(9), pp1961-1969 (2003) I. Shlimak, V. Ginodman, M. Levin, M. Potemski, D.K. Maude, K.-J. Friedland and D.J. Paul "Longitudinal conductivity in Si/SiGe heterostructures at integer filling factors" Physical Review B 68, Art. 075321_1-5 (2003) R.W. Kelsall, Z. Ikonic, P.Harrison, S.A. Lynch, R. Bates, D.J. Paul, D.J. Norris, S.L. Liew, A.G. Cullis, D.J. Robbins, P. Murzyn, C.R. Pidgeon, D.D. Arnone and R.A. Soref, "Terahertz emission from silicon germanium quantum cascades" pp367-382 in "Towards the First Silicon Laser" Eds L. Pavesi et al., Kluwer Academic Publishers (2003) A. Lewalle, M. Pepper, C.J.B. Ford, E.H. Hwang, S. Das Sarma, D.J. Paul and G. Redmond, “The relative importance of electron-electron interactions compared to disorder in the two-dimensional 'metallic' state” Physical Review B 66, pp075324_1-5 (2002) S.A. Lynch, R. Bates, D.J. Paul, D.J. Norris, A.G. Cullis, Z.Ikonic, R.W. Kelsall, P. Harrison, D.D. Arnone and C.R. Pidgeon, “Intersubband electroluminescence from Si/SiGe cascade emitters at terahertz frequencies” Applied Physics Letters 81, pp1543-1545 (2002) C.R. Pidgeon, P. Murzyn, J-P.R. Wells, I.V. Bradley, Z. Ikonic, R.W. Kelsall, P. Harrison, S.A. Lynch, D.J. Paul, D.D. Arnone, D.J. Robbins, D.J. Norris and A.G. Cullis, “Picosecond intersubband dynamics in p-Si/SiGe quantum well emitters” Applied Physics Letters 80, pp 1456-1458 (2002) D.J. Paul, “Nanoelectronics” Encylopedia of Physical Science and Technology, Third Edition, Academic Press (2002) P. See and D.J. Paul, “Scaled performance of Si/SiGe resonant tunnelling diodes” IEEE Electron Device Letters 22(12), pp 582-584 (2001) P. See, D.J. Paul, B. Holländer, S. Mantl, I.V. Zozoulenko and K.-F. Berggren, “High dc performance Si/Si1-xGex resonant tunelling diodes” IEEE Electron Device Letters 22(4), pp182-184 (2001) D.J. Paul, P. See, I.V. Zozoulenko, K.-F. Berggren, B. Holländer, S. Mantl, N. Griffin, B.P. Coonan, G. Redmond and G.M. Crean “Si/SiGe resonant tunnelling diodes with graded spacer wells” Applied Physics Letters 78(26), pp4184-4186 (2001) D.J. Paul, P. See, I.V. Zozoulenko, K.-F. Berggren, B. Kabius, B. Holländer and S. Mantl “Si/SiGe electron resonant tunnelling diodes” Applied Physics Letters 77(11), pp1653-1655 (2000) D.J. Paul “Silicon germanium makes its mark” Physics World 13(2), pp27-32 (2000) D.J. Paul, “Silicon germanium strianed layer materials in microelectronics” Advanced Materials 11(3), pp191-204 (1999) A.C. Churchill, D.J. Robbins, D.J. Wallis, N. Griffin, D.J. Paul, A.J. Pidduck, W.Y. Leong and G.M. Williams “2D electron gas mobility as a function of virtual substrate quality in strained Si/SiGe heterojunctions” Journal of Vacuum Science and Technology B 16, pp1634-1638 (1998) N. Griffin, D. D. Arnone, D. J. Paul, M. Pepper, D. J. Robbins, A. C. Churchill and J. M. Fernández “Cyclotron resonance measurements of silicon/silicon-germanium two-dimensional electron gases with differing strain” Journal of Vacuum Science and Technology B 16(3), pp1655-1658 (1998) D.J. Paul, A. Ahmed, M. Pepper, A.C. Churchill, D.J. Robbins and D J Wallis “Electrical properties and uniformity of two dimensional electron gases grown on cleaned SiGe virtual substrates” Journal of Vacuum Science and Technology B16(3), pp1644-1647 (1998) A.C. Churchill, D.J. Robbins, D.J. Wallis, N. Griffin, D.J. Paul and A.J. Pidduck “High mobility two dimensional electron gases in Si/SiGe heterostructures on relaxed SiGe layers grown at high temperature” Semiconductor Science and Technology 12, pp943-945 (1997) D.J. Paul, N. Griffin, D.D. Arnone, M. Pepper, C.J. Emeleus, P.J. Phillips and T.E. Whall “Low temperature characterisation of modulation doped SiGe grown on bonded silicon-on insulator” Applied Physics Letters 69(18), pp2704-2706 (1996) D.J. Paul, V.J. Law and G.A.C. Jones “Si1-xGex pulsed plasma etching using CHF3 and H2” Journal of Vacuum Science and Technology B 13(6), pp2234-2237, (1995) D.J. Paul, J.R.A. Cleaver, H. Ahmed and T.E. Whall “Co-tunnelling of holes in silicon based structures” Physical Review B 49(2), pp16514-16517 (1994) D.J. Paul, J.R.A. Cleaver, H. Ahmed and T.E. Whall “Coulomb blockade in silicon based structures at temperatures up to 50K” Applied Physics Letters 63(5), pp631-632 (1993) D.J. Paul, S.A. Lynch, P. Townsend, Z. Ikonic, R.W. Kelsall, P. Harrison, S.L. Liew, D.J. Norris, A.G. Cullis, J. Zhang, M. Bain, H.S. Gamble, W.R. Tribe and D.D. Arnone, "Towards a Si/SiGe quantum casacde laser for terahertz applications" Materials Research Society Symposium Proceedings 832, pp56-68 (2005) D.J. Paul, P. Townsend, S.A. Lynch, R.W. Kelsall, Z. Ikonic, P. Harrison, D.J. Norris, S.L. Liew, A.G. Cullis, X. Li, J. Zhang, M. Bain, H.S. Gamble, W.R. Tribe and D.D. Arnone "In search of a Si/SiGe terahertz quantum cascade laser" IEEE Topical Meeting on Silicon Monolithic Intergrated Circuits in RF Systems, Digest Of Papers : pp143-146, September (2004) R.W. Kelsall, Z. Ikonic, P. Harrison, D.J. Paul, S.A. Lynch, R. Bates, D.J. Norris, S.L. Liew, A.G. Cullis, D.D. Arnone, D.J. Robbins and R.A. Soref, "Towards SiGe terahertz VCSELs" Materials Science Forum 453-454, pp1-8 (2004) I. Shlimak, V. Ginodman, M. Levin, M. Potemski, D.K. Maude, A. Gerber, A. Milner and D.J. Paul "Conductivity of weakly and strongly localised electrons in a n-type Si/SiGe heterostructure" Proceedings of the 10th Conference on Hopping and Related Phenomena 10, pp67-70 (2004) S.L. Liew, D.J. Norris, A.G. Cullis, R.W. Kelsall, P. Harrison, Z. Ikonic, D.J. Paul, S.A. Lynch, R. Bates, D.D. Arnone and D.J. Robbins, "Analysis of terhertz emitting SiGe quantum cascade structures by transmission electron microscopy" Institute of Physics Conference Series 180, pp155-158 (2003) A.C.K. Chang, D.J. Norris, A.G. Cullis and D.J. Paul, "Advanced TEM analysis of strain-balanced Si/SiGe resonant tunnelling diodes structures" Institute of Physics Conference Series 180, pp163-168 (2003) C.R. Pidgeon, P. Murzyn, J.-P.R. Wells, Z. Ikonic, R.W. Kelsall, P. Harrison, S.A. Lynch, D.J. Paul, D.D. Arnone and D.J. Robbins, "THz intersubband dynamics in p-Si/SiGe quantum well emitter structures" Physica Statui Solidi (b) 237, pp381-385 (2003) A. Lewalle, M. Pepper, C.J.B. Ford, D.J. Paul and G. Redmond, "Weak localisation and the 'destruction' of the two-dimensional metallic behaviour by a parallel magnetic field" Institute of Physics Conference Series 171, L1.5 (2003) D.J. Paul, S.A. Lynch, R. Bates, Z. Ikonic, R.W. Kelsall, P. Harrison, D.J. Norris, S.L. Liew, A.G. Cullis, C.R. Pidgeon, P. Murzyn, W. Tribe and D.D. Arnone "Si/SiGe quantum cascade emitters for terahertz applications" Proc. 3rd International Conference on SiGe(C) Epitaxy and Heterostructures (2003) S. Olsen, L. Driscoll, K. Kwa, S. Chattopadhyay, A. O'Neill, A. Waite, Y. Tang, A. Evans, D.J. Norris, A.G. Cullis, D.J. Paul and D.J. Robbins "High performance strained Si/SiGe nMOSFETs using a novel CMOS architecture" Proc. 3rd International Conference on SiGe(C) Epitaxy and Heterostructures (2003) S.A. Lynch, D.J. Paul, R. Bates, D.J. Norris, A.G. Cullis, Z. Ikonic, R.W. Kelsall, P. Harrison, D.D. Arnone and C.R. Pidgeon, "Far intrared (THz) electroluminescence from Si/SiGe quantum cascade heterostructures" Proc. SPIE R.W. Kelsall, Z. Ikonic, P. Harrison, S.A. Lynch, R. Bates, D.J. Paul, D.J. Norris, S.L. Liew, A.G. Cullis, D.J. Robbins, P. Murzyn, C.R. Pidgeon and D.D. Arnone, "Terahertz intersubband emission from silicon-germanium quantum cascades" Proc. IEEE Tenth International Conference on Terahertz Electronics pp9-12 (2002) M. Pepper, A. Lewalle, A.R. Hamilton, M.Y. Simmons, C.J.B. Ford, D.J. Paul and D.A. Ritchie, "Localisation and Metal-Insulator Transitions in 2D" Proc. High Magnetic Field Conference, Oxford, August 2002 D.J. Paul, S.A. Lynch, R. Bates, Z. Ikonic, R.W. Kelsall, P. Harrison, C.R. Pidgeon,P. Murzyn, J.-P.R. Wells, I.V. Bradley, D.J. Norris, S.L. Liew, A.G. Cullis,W. Tribe and D.D. Arnone "Si/SiGe quantum cascade emitters for terahertz applications" Proc. International Conference of the Physics of Semiconductors, July / August 2002 D.J. Paul, S.A. Lynch, R. Bates, Z. Ikonic, R.W. Kelsall, P. Harrison, D.J. Norris, S.L. Liew, A.G. Cullis, P. Murzyn, C. Pidgeon, D.D. Arnone and D.J. Robbins "Electroluminescence from Si/SiGe quantum cascade emitters" Physica E 16, pp309-314 (2003) R. Bates, S.A. Lynch, D.J. Paul, D.J. Norris, A.G. Cullis, Z.Ikonic, R.W. Kelsall, P. Harrison, D.D. Arnone and C.R. Pidgeon, “Intersubband electroluminescence from Si/SiGe cascade emitters at terahertz frequencies” CLEO Technical Digest 2002, pp629-630 (2002) (Paper CFB2) S.A. Lynch, D.J. Paul, R. Bates, P. Murzyn, C.R. Pidgeon, Z. Ikonic, R.W. Kelsall, P. Harrison, D.J. Norris, A.G. Cullis, and D.D. Arnone, “Intersubband and impurity electroluminescence in Si/SiGe heterostructures at terahertz frequencies” CLEO Technical Digest 2002, p629 (2002) (Paper CFB1) D.J. Paul, S.A. Lynch, R. Bates, Z.Ikonic, R.W. Kelsall, P. Harrison, D.J. Norris, S.L. Liew, A.G. Cullis, D.D. Arnone, C.R. Pidgeon, P. Murzyn, J.-P.R. Wells and I.V. Bradley, "Si/SiGe quantum cascade emitters for terahertz applications" Physica E 16, pp147-155 (2003) A. Lewalle, M. Pepper, C.J.B. Ford, D.J. Paul, N. Griffin, B.P. Coonan, G. Redmond and G.M. Crean, “Investigation of the zero field 2D 'metallic' state with rs and kFl controlled independently” Physica E 12, pp616-619 (2002) C.R. Pidgeon, P. Murzyn, J-P.R. Wells, I.V. Bradley, Z. Ikonic, R.W. Kelsall, P. Harrison, S.A. Lynch, D.J. Paul, D.D. Arnone, D.J. Robbins, D.J. Norris and A.G. Cullis, “THz intersubband dynamics in p-Si/SiGe quantum well structures” Physica E 13, pp904-907 (2002) S.A. Lynch, S.S. Dhillon, R. Bates, D.J. Paul, D.D. Arnone, D.J. Robbins, Z. Ikonic, R.W. Kelsall, P. Harrison, D.J. Norris, A.G. Cullis, C.R. Pidgeon, P. Murzyn and A.Loudon, “Si-based electroluminescence at THz frequencies” Material Science and Engineering B 89, pp 10-12 (2002) D.J. Paul, P. See, B. Holländer, S. Mantl, I.V. Zozoulenko, K.F- Berggren, N. Griffin, B.P. Coonan, G. Redmond and G.M. Crean, “n-type Si/SiGe resonant tunnelling diodes” Material Science and Engineering B 89, pp 26-29 (2002) D.J. Paul, A. Ahmed, A.C. Churchill, D.J. Robbins and W.Y. Leong, “Low dimensional inverted Si/SiGe modulation-doped electron gases using selective ex-situ ion implantation” Material Science and Engineering B 89, pp111-115 (2002) R.B. Dunford, D.J. Paul, M. Pepper, B.P. Coonan, N. Griffin, G. Redmond, G.M. Crean, B. Holländer and S. Mantl,”Si/Si1-xGex heterostructure field effect transistors fabricated using a low thermal budget CMOS process” Microelectronic Engineering 53(1-4), pp209-212 (2000) R.B. Dunford, A. Ahmed, D.J. Paul, M. Pepper, A.C. Churchill, D.J. Robbins and A.J. Pidduck “Inverted modulation-doped n-type Si/SiGe heterostructures” Microelectronic Engineering 53(1-4) pp205-208 (2000) R.B. Dunford, N. Griffin, D.J. Paul, M. Pepper, D.J. Robbins, A.C. Churchill and W.Y. Leong “Schottky gating high mobility Si/Si1-xGex 2D electron systems” Thin Solid Films 369, pp316-139 (2000) A. Ahmed, R.B. Dunford, D.J. Paul, M. Pepper, A.C. Churchill, D.J. Robbins and W.Y. Leong “Si/SiGe n-type inverted modulation-doping using ion implantation” Thin Solid Films 369, pp324-327 (2000) B.P. Coonan, N. Griffin, J.T. Beechinoor, M. Murtagh, G. Redmond, G.M. Crean, B. Holländer, S. Mantl, S. Bozzo, J.-L. Lazzari, F. Arnaud d.Avitaya, J. Derrien and D.J. Paul “Investigations of Si/SiGe heterostructure material using non-destructive optical techniques” Thin Solid Films 364, pp75-79 (2000) D.J. Paul, B. Coonan, G. Redmond, G.M. Crean, B. Holländer, S. Mantl, I. Zozoulenko, K.-F. Berggren, J.-L. Lazzari, F. Arnaud d’Avitaya and J. Derrien, “Silicon quantum integrated circuits” Proceedings of The Future of Microelectronics: Off the Beaten Path, pp183-192 Wiley (1999) D.J. Paul, B. Coonan, G. Redmond, B.J. O’Neill, G.M. Crean, B. Holländer, S. Mantl, I. Zozoulenko, K.-F. Berggren, J.-L. Lazzari, F. Arnaud d’Avitaya and J. Derrien, “Silicon quantum integrated circuits:- An attempt to fabricate silicon-based quantum devices using CMOS fabrication techniques” Thin Solid Films 336, pp130-136 (1999) C. E. Norman, N. Griffin, D. D. Arnone, D. J. Paul, M. Pepper, B. Gallas and J. M. Fernández “EBIC of strained Si/SiGe 2DEGs showing lateral electron confinement” Solid State Phenomena 63, pp25-32 (1998) N. Griffin, D.D. Arnone, D.J. Paul, C.E. Norman, B. Gallas, J.M. Fernández, and M. Pepper “Dislocation-induced lateral depletion in a high mobility Si/SiGe two dimensional electron gas” Proc. ICPS (1998) N. Griffin, D.D. Arnone, D.J. Paul, M. Pepper, D.J. Robbins and A.C. Churchill “Far-infrared cyclotron resonance study of the effect of strain and localisation in Si/SiGe 2DEGs” Solid State Electronics 42(7-8), pp1159-1163 (1998) D.J. Paul “Silicon germanium heterostructures in electronics:- The present and the future” Thin Solid Films 321, pp172-180 (1998) D.J. Paul, A. Ahmed, N. Griffin, M. Pepper, A.C. Churchill, D.J. Robbins and D J Wallis “Electrical properties of two dimensional electron gases grown on cleaned SiGe virtual substrates” Thin Solid Films 321, pp181-185 (1998) N. Griffin, D.J. Paul, M. Pepper, S. Taylor, W. Eccleston, J.M. Fernández and B.A. Joyce “Gating high mobility silicon germanium heterostructures” Journal of Microelectronic Engineering 35, pp309-312 (1997) D.J. Paul, J.M. Ryan, M. Pepper, A.N. Broers, T.E. Whall, J.M. Fernández and B.A. Joyce “Electron beam induced damage of silicon germanium” Journal of Microelectronic Engineering 35, pp59-62 (1997) D.J. Paul, J.M. Ryan, P.V. Kelly, G.M. Crean, J. M. Fernández, M. Pepper, A.N. Broers and B.A. Joyce “Investigation of electron-beam and optical induced damage in high mobility SiGe heterostructures” Solid State Electronics 41(10), pp1509-1513 (1997) D.J. Paul, J.M. Ryan, M. Pepper, A.N. Broers, T.E. Whall, J.M. Fernández and B.A. Joyce “Electron beam induced damage of silicon germanium” Journal of Vacuum Science and Technology B 14(6), pp3834-3838 (1996) J.M. Ryan, D.J. Paul, M. Pepper, A.N. Broers, T.E. Whall, J.M. Fernández and B.A. Joyce “Fabrication of SiGe quantum devices by electron-beam induced damage” Superlattices and Microstructures 21(1), pp29-36 (1997) D. Williams, E. Pettersen, D.J. Paul and H. Ahmed “High resolution scanning electron microscopy in mesoscopic physics” Institute of Physics Conference Series Number 134: Section 5, pp249-252 (1993) D.J. Paul, J.R.A. Cleaver and H. Ahmed “Fabrication of wires in silicon germanium material” Microelectronics Engineering 21, pp349-352 (1993)