Specific features of defect formation in the n­Si <P> single crystals at electron irradiation

• Main Authors: Sergiy Luniov, Andriy Zimych, Mykola Khvyshchun, Mykola Yevsiuk, Volodymyr Maslyuk
• Format: Article
• Language: English
• Published: PC Technology Center 2018-12-01
• Series: Eastern-European Journal of Enterprise Technologies
• Subjects: silicon single crystals; infrared fourier spectroscopy; hall effect; uniaxial pressure; radiation defects; deep energy levels
• Online Access: http://journals.uran.ua/eejet/article/view/150959

Based on measurements of infrared Fourier spectroscopy, Hall effect, and the tensor Hall-effect, we have established the nature, and determined the concentration, of the main types of radiation defects in the single crystals n-Si <P>, irradiated by different fluxes of electrons with an energy of 12 MeV. It is shown that for the examined silicon single crystals at electronic irradiation, it is quite effective to form a new type of radiation defects belonging to the VOiP complexes (A-center, modified with an additive of phosphorus). Based on the solutions to electroneutrality equation, we have derived dependences of activation energy for the deep level E1=EC–0,107 eV, which belongs to the VOiP complex, on uniaxial pressure along the crystallographic directions [100] and [111]. By using a method of least squares, we have constructed approximation polynomials for calculating these dependences. At orientation of the deformation axis along the crystallographic direction [100], the deep level E1=EC–0.107 eV will be decomposed into two components with a different activation energy. This explains the nonlinear dependences of activation energy of the deep level E1=EC–0.107 eV on the uniaxial pressure P≤0.4 GPa. For pressures P>0.4 GPa, the decomposition of this deep level is significant and one can assume that the deep level of the VOiP complex will interact only with two minima in the silicon conduction zone while a change in the magnitude of activation energy would be linear for deformation. For the case of uniaxial pressure P≤0.4 GPa along the crystallographic direction [111] a change in the activation energy for the VOiP complex is described by a quadratic dependence. Accordingly, the offset in the deep level E1=EC–0.107 eV for a given case is also a quadratic function for deformation. Different dependences of activation energy of the VOiP complex on the orientation of a deformation axis relative to different crystallographic directions may indicate the anisotropic characteristics of this defect. The established features in defect formation for the n-Si <P> single crystals, irradiated by electrons, could be applied when designing various instruments for functional electronics based on these single crystals