Lithuanian Journal of Physics article / Lietuvos fizikos žurnalo straipsnis

NEUTRON IRRADIATION INFLUENCE ON MOBILITY AND COMPENSATION OF DARK CONDUCTIVITY IN SILICON
Juozas Vidmantis Vaitkus, Algirdas Mekys, Vytautas Rumbauskas, and Jurgis Storasta
Institute of Applied Research and Department of Semiconductor Physics, Vilnius University, Saulėtekio 3, LT-10222 Vilnius, Lithuania
E-mail: juozas.vaitkus@ff.vu.lt

Received 19 December 2015; revised 27 April 2016; accepted 21 June 2016

The electrical properties of the neutron irradiated Si were analysed by means of the Hall effect and magnetoresistance temperature dependence. It was demonstrated that the electron mobility decreased with increasing the neutron fluence in a wide fluence range, and the microinhomogeneities in samples caused differences between the mobility values from the measured Hall and magnetoresistance effects. Exploiting the magnetoresistance mobility temperature dependence, the free carrier concentration dependence on temperature was analysed. It was found that the neutron irradiation introduced deep levels in the upper part of the bandgap, but their contribution decreased with increasing the neutron fluence – that is explained by more effective generation of acceptor type levels in the middle or lower part of the bandgap. The activation energy of the free carrier concentration did not follow the homogeneous semiconductor model, so the dark conductivity origin, that is related to the modified cluster model and cluster environment, was proposed.

Keywords: radiation defects, electron mobility, Hall and magnetoresistance mobilities, clusters, silicon
PACS: 72.10.Fk, 72.20.My, 72.80.Cw, 72.20.Fr, 71.55.Cn

APŠVITOS NEUTRONAIS ĮTAKA ELEKTRONŲ JUDRIUI IR TAMSINIO LAIDUMO KOMPENSACIJAI SILICIO KRISTALUOSE

Juozas Vidmantis Vaitkus, Algirdas Mekys, Vytautas Rumbauskas, Jurgis Storasta
Vilniaus universiteto Taikomųjų mokslų institutas ir Fizikos fakulteto Puslaidininkių fizikos katedra, Vilnius, Lietuva

apšvitintuose reaktoriaus neutronais, panaudojant Holo efekto ir magnetovaržos metodikas. Analizuotos elektronų judrio ir krūvininkų koncentracijos prieklausos nuo neutronų įtėkio ir temperatūros. Parodyta, kad elektronų judris mažėja didinant neutronų įtėkį plačiame įtėkių intervale, ir bandiniuose sukuriami mikronevienalytiškumai, lemiantys elektronų judrio, nustatomo iš Holo efekto ir magnetovaržos, skirtumus. Panaudojant magnetovaržinio judrio vertes nustatyta elektronų koncentracijos prieklausa nuo temperatūros, o ją analizuojant gautos lokalinių lygmenų aktyvacijos energijos ir jų koncentracijos. Gauta, kad apšvita neutronais sukuria lygmenis viršutinėje draustinės juostos pusėje, tačiau jų įtaka tamsiniam kristalų elektriniam laidumui didėjant neutronų įtėkiui mažėja, nes sukuriama didesnė akceptorių koncentracija draustinės juostos viduryje ar jos apatinėje dalyje. Nustatyta, kad laisvųjų krūvininkų koncentracijos aktyvacijos energija netenkina vienalyčio puslaidininkio modelio, todėl sukurtas modifikuotas defektų klasterio modelis ir paaiškinta puslaidininkio tamsinio laidumo prigimtis, nusakanti klasterio ir jo apsupties savybes.

References / Nuorodos

[1] K. Wehe, Current trends in ionizing radiation detectors, Nucl. Eng. Technol. 38, 311–318 (2006),
http://www.kns.org/jknsfile/v38/JK0383111.pdf
[2] M. Moll, J. Adey, A. Al-Ajili, G. Alfieri, P.P. Allport, M. Artuso, S. Assouak, B.S. Avset, L. Barabash, A. Barcz, et al., Development of radiation tolerant semiconductor detectors for Super-LHC, Nucl. Instrum. Methods A 546, 99–107 (2005),
http://dx.doi.org/10.1016/j.nima.2005.03.044
[3] M. Moll, E. Fretwurst, and G. Lindström, Investigation on the improved radiation hardness of silicon detectors with high oxygen concentration, Nucl. Instrum. Methods A 439, 282–292 (2000),
http://dx.doi.org/10.1016/S0168-9002(99)00842-6
[4] M. Huhtinen, Simulation of non-ionising energy loss and defect formation in silicon, Nucl. Instrum. Methods A 491, 194–215 (2002),
http://dx.doi.org/10.1016/S0168-9002(02)01227-5
[5] T.J. Brodbeck, A. Chilingarov, T. Sloan, E. Fretwurst, M. Kuhnke, and G. Lindstroem, Carrier mobilities in irradiated silicon, Nucl. Instrum. Methods A 477, 287–292 (2002),
http://dx.doi.org/10.1016/S0168-9002(01)01858-7
[6] E. Borchi, M. Bruzzi, B. Dezillie, S. Lazanu, Z. Li, and S. Pirollo, Hall effect analysis in irradiated silicon samples with different resistivities, IEEE Trans. Nucl. Sci. 46, 834–838 (1999),
http://dx.doi.org/10.1109/23.790687
[7] V. Eremin and Z. Li, Carrier drift mobility study in neutron irradiated high purity silicon, Nucl. Instrum. Methods A 362, 338 (1995),
http://dx.doi.org/ 10.1016/0168-9002(95)00381-9
[8] R.H. Bube, Interpretation of Hall and photo-Hall effects in inhomogeneous materials, Appl. Phys. Lett. 13, 136–139 (1968),
http://dx.doi.org/10.1063/1.1652542
[9] W. Siegel, S. Schulte, C. Reichel, G. Kuhnel, and J. Monecke, Anomalous temperature dependence of the Hall mobility in undoped bulk GaAs, J. Appl. Phys. 82, 3832–3835 (1997),
http://dx.doi.org/10.1063/1.365747
[10] V.G. Karpov, A.J. Shik, and B.I. Shklovskii, Theory of the Hall effect in randomly inhomogeneous semiconductors, Sov. Phys. Semiconduct. 16, 901–903 (1982)
[11] J. Vaitkus, A. Mekys, G. Mockevičius, J. Storasta, and N. Vainorius, in: Materials of 4th International Conference on Radiation Interaction with Material and Its Use in Technologies 2012 (Technologija, Kaunas, 2012) pp. 33–38
[12] D.K. Schroder, Semiconductor Material and Device Characterization (Wiley, N. Y., 1990),
http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0471739065.html
[13] P. Norton, T. Braggins, and H. Levinstein, Impurity and lattice scattering parameters as determined from Hall and mobility analysis in n-type silicon, Phys. Rev. B 8, 5632–5653 (1973),
http://dx.doi.org/10.1103/PhysRevB.8.5632
[14] A.C. Beer, Galvanomagnetic Effects in Semiconductors (Academic Press, N. Y., 1963),
https://www.amazon.co.uk/Galvanomagnetic-effects-semiconductors-physics-Supplements/dp/B0000CM61T/
[15] A. Mekys, V. Rumbauskas, J. Storasta, L. Makarenko, and J.V. Vaitkus, Defect analysis in fast electron irradiated silicon by Hall and magnetoresistivity means, Nucl. Instrum. Methods B 338, 95–100 (2014),
http://dx.doi.org/10.1016/j.nimb.2014.08.007
[16] A. Mekys, V. Rumbauskas, J. Storasta, L. Makarenko, N. Kazuchits, and J.V. Vaitkus, Hall effect and magnetoresistance investigation of fast electron irradiated silicon, Lith. J. Phys. 54, 94–98 (2014),
http://dx.doi.org/10.3952/lithjphys.54204
[17] C. Jacoboni and P. Lugli, The Monte Carlo Method for Semiconductor Device Simulation (Springer Science & Business Media, 2012),
http://dx.doi.org/10.1007/978-3-7091-6963-6
[18] K.W. Böer, Handbook of the Physics of Thin-Film Solar Cells (Springer Science & Business Media, Berlin, 2014),
http://dx.doi.org/10.1007/978-3-642-36748-9
[19] B.K. Ridley, Reconciliation of the Conwell–Weisskopf and Brooks–Herring formulae for charged-impurity scattering in semiconductors: Third-body interference, J. Phys. C 10(10), 1589–1593 (1977),
http://dx.doi.org/10.1088/0022-3719/10/10/003
[20] E. Verbitskaya, V. Eremin, Z. Li, J. Harkonen, and M. Bruzzi, Concept of Double Peak electric field distribution in the development of radiation hard silicon detectors, Nucl. Instrum. Methods A 583, 77–86 (2007),
http://dx.doi.org/10.1016/j.nima.2007.08.228
[21] H.J. Stein., Electrical studies of neutron-irradiated n-type Si: defect structure and annealing, Phys. Rev. 163(3), 801–808 (1967),
http://dx.doi.org/10.1103/PhysRev.163.801
[22] H.J. Juretschke, R. Landauer, and J.A. Swanson, Hall effect and conductivity in porous media, J. Appl. Phys. 27, 838 (1956),
http://dx.doi.org/10.1063/1.1722496
[23] W. Siegel, S. Schulte, G. Kühnel, and J. Monecke, Hall mobility lowering in undoped n-type bulk GaAs due to cellular-structure related nonuniformities, J. Appl. Phys. 81, 3155–9 (1997),
http://dx.doi.org/10.1063/1.364350
[24] L.R. Weisberg, Anomalous mobility effects in some semiconductors and insulators, J. Appl. Phys. 5, 1817–1821 (1962),
http://dx.doi.org/10.1063/1.1728839
[25] C. Jacoboni, C. Canali, G. Ottaviani, and A. Alberigi Quaranta, A review of some charge transport properties of silicon, Solid State Electron. 20(2), 77–89 (1977),
http://dx.doi.org/10.1016/0038-1101(77)90054-5
[26] K. Seeger, Semiconductor Physics (Springer-Verlag, Wien, New York, 1973),
http://dx.doi.org/10.1007/978-3-7091-4111-3
[27] W. Zhao and D. Jena, Dipole scattering in highly polar semiconductor alloys, J. Appl. Phys. 96, 2095–2101 (2004),
http://dx.doi.org/10.1063/1.1767615
[28] S.M. Sze, Physics of Semiconductor Devices (Wiley, New York, 1981),
http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0471673242.html
[29] J.S. Blakemore, Semiconductor Statistics (Pergamon Press, Oxford, 1962),
https://www.amazon.co.uk/Semiconductor-Statistics-International-Monographs-Semiconductors/dp/1483116522/
[30] B.J. Svensson, M.J. Rayson, P.R. Briddon, J. Coutinho, V.P. Markevich, A.R. Peaker, B. Hamilton, S.B. Lastovskii, and L.I. Murin, Electronic and dynamical properties of the silicon trivacancy, Phys. Rev. B 86, 174101 (2012),
http://dx.doi.org/10.1103/PhysRevB.86.174101
[31] G. Lindström, M. Moll, and E. Fretwurst, Radiation hardness of silicon detectors – a challenge from high-energy physics, Nucl. Instrum. Methods A 426, 1–15 (1999),
http://dx.doi.org/10.1016/S0168-9002(98)01462-4
[32] V. Kalendra, E. Gaubas, V. Kazukauskas, E. Zasinas, and J. Vaitkus, Photoconductivity spectra and deep levels in the irradiated p⁺–n–n⁺ Si detectors, Nucl. Instrum. Methods A 612, 555–558 (2010),
http://dx.doi.org/10.1016/j.nima.2009.08.043
[33] P.F. Ermolov, D.E. Karmanov, A.K. Leflat, V.M. Manankov, M.M. Merkin, and E.K. Shabalina, Neutron irradiation-induced effects caused by divacancy clusters with a tetravacancy core in float-zone silicon, Semiconductors 36, 1114–1122 (2002),
http://dx.doi.org/10.1134/1.1513854
[34] R.M. Fleming, C.H. Seager, D.V. Lang, P.J. Cooper, E. Bielejec, and J.M. Campbell, Effects of clustering on the properties of defects in neutron irradiated silicon, J. Appl. Phys. 102, 043711 (2007),
http://dx.doi.org/10.1063/1.2769783
[35] P.C. Serce, Multiphonon-assisted tunneling through deep levels: A rapid energy-relaxation mechanism in nonideal quantum-dot heterostructures, Phys. Rev. B 51, 14532–14541 (1995),
http://dx.doi.org/10.1103/PhysRevB.51.14532