Journal of Modern Physics, 2012, 3, 383-387 doi:10.4236/jmp.2012.35053 Published Online May 2012 (http://www.SciRP.org/journal/jmp) In-Situ Study of Silicon Single Crystals Conductivity under Electron Irradiation Hrant N. Yeritsyan 1* , Aram A. Sahakyan 1 , Sergey K. Nikoghosyan 1 , Vachagan V. Harutyunyan 1 , Karen Sh. Ohanyan 1 , Norair E. Grigoryan 1 , Eleonora A. Hakhverdyan 1 , Aghasi S. Hovhannisyan 1 , Vahan A. Sahakyan 2 , Kamo A. Movsisyan 2 , Artur V. Hovhannisyan 3 1 A.I. Alikhanyan National Science Laboratory (YerPhI), Yerevan, Armenia 2 Institute of Metrology Republic of Armenia, Yerevan, Armenia 3 State Nuclear Safety Regulatory Committee by the Government of Armenia, Yerevan, Armenia Email: * Grant@yerphi.am Received February 23, 2012; revised March 12, 2012; accepted March 23, 2012 ABSTRACT The influence of electron radiation on the properties of semiconducting silicon single crystals (Si)—both n- and p-types (currently one of the most widely applied material in the electronic technology) was studied under the electron irradia- tion process in-situ in air (in common conditions). Higher value of electro-conductivity (σ) during the irradiation proc- ess with respect to after irradiation was observed, which was explained by ionization and capture mechanisms resulting in the formation of non-equilibrium carriers (hole-electron pairs). The kinetics of radiation defects generation, their physical nature, temperature stability and relaxation are examined. Structural radiation defects formation: point and complexes, their influence on the silicon conductivity are considered. Keywords: Silicon; Radiation Defects (RD); Carrier Concentration; Carrier Mobility; Conductivity 1. Introduction There are numerous investigations concerning the influ- ence of irradiations on the properties of solid states (in- cluding silicon) which are carried out before and after irr- adiation [for example 1-14]. The works on studying the properties of solid states directly under the irradiation process are very scarce [15-20]. However, these works describe the situation in more adequate conditions and are important in terms of using silicon devices, for in- stance in space, nuclear plants, in particle accelerators. In present study silicon conductivity (the main property for practical usage) measurements are carried out directly under the electron irradiation process. The nature of radiation structural defects depends on type, energy, dose and intensity of radiation [1,2,4]. The charged particles interact with atoms in the material by means of long-distance Coulomnic forces, resulting in frequent, but weak collisions. The neutral particles trans- fer large amount of energy to the atomic nucleus and the constituent atoms undergo infrequent, but energetic col- lisions. In the first process, the formation of large number of simple vacancy-interstitial type atoms predominates; while in the second case large disordered areas (clusters), consisting of hundreds, thousands of simple defects are formed. The difference in these mechanisms results in different properties of the radiated materials, and it is very difficult to specify common equivalents for radia- tion by charged particles or for radiation by neutral parti- cles. However, it is possible to find common features when comparing the effect of different charged particles on a particular material. For example, when modeling some effects in semiconductors it is reasonable to substitute protons and α-particles with energy of several МeV—by electrons with energies of tens MeV. Nevertheless, each type of radiation-substitution requires its own particular and detailed analysis, because even when both kinds of radiation consist of charged particles there is no absolute equivalence, because of different defect densities in the tracks of particles with different masses. In this paper the results of in-situ measurements of specific conductivity of silicon single crystals (both n- and p-type) under electron irradiation with energy 8 MeV in air (in common conditions) are presented. 2. Experimental Procedure Both p- and n-types of silicon samples with initial electro * Corresponding author. Copyright © 2012 SciRes. JMP