Radiation Damage In Semiconductors Research Articles

Determination of radiation hardness of silicon diodes

In this paper, we describe an experiment aimed to measure the physical observables, which can be used for the assessment of the radiation hardness of commercially available silicon photo diodes commonly used as nuclear detectors in particle accelerator laboratories. The experiment adopted the methodology developed during the International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP No. F11016) “Utilization of Ion Accelerators for Studying and Modelling Ion Induced Radiation Defects in Semiconductors and Insulators”.This methodology is based on the selective irradiation of micrometer-sized regions with different fluences of MeV ions using an ion microbeam and on the measurement of the charge collection efficiency (CCE) degradation by Ion Beam Induced Charge (IBIC) microscopy performed in full depletion condition, using different probing ions.The IBIC results are analyzed through a theoretical approach based on the Shockley-Read-Hall model for the free carrier recombination in the presence of ion-induced deep traps. This interpretative model allows the evaluation of the material radiation hardness in terms of recombination parameters for both electrons and holes.The device under study in this experiment was a commercial p-i-n photodiode, which was initially characterized by i) standard electronic characterization techniques to determine its doping and ii) the Angle-Resolved IBIC to evaluate its effective entrance window. Nine regions of (100 × 100) µm2 were irradiated with 11.25 MeV He ions up to a maximum fluence of 3·1012 ions/cm2. The CCE degradation was measured by the IBIC technique using 11.25 MeV He and 1.4 MeV He as probing ions.The model presented here proved to be effective for fitting the experimental data. The fitting parameters correspond to the recombination coefficients, which are the key parameters for the characterization of the effects of radiation damage in semiconductors.

A deep-level transient spectroscopy variation for the determination of displacement threshold energies in GaAs

The deep-level transient spectroscopy (DLTS) method is optimized for the observation of radiation damage in semiconductors. A new isothermal variation of the technique is applied to the study of displacement defects in GaAs in order to determine threshold energies and displacement cross sections. A pronounced anisotropy is found for the threshold energy. A linearly increasing displacement probability function is shown to properly model the displacement cross section in <100≳ direction, as compared with the <111≳ direction which requires only a simple step function. Anisotropy leads to a tailing off in the displacement cross section at energies below an ‘‘effective’’ threshold of about 15.5 eV in the <100≳ direction, indicating that the <111≳ direction is more sensitive to displacement damage than the <100≳ direction. Differences in the damage between these two directions are as large as a factor of 2.

A Microscopic View of Radiation Damage in Semiconductors Using EPR as a Probe Invited Paper

This is the text of a tutorial talk on the use of electron paramagnetic resonance (EPR) as a "microscopic" tool in the study of radiation-produced defects in semiconductors. The basic concepts of EPR and its general applicability to point defects in semiconductors are outlined. As an illustrative example, the study of a p-type (aluminum doped) silicon sample is described from 20.4°K irradiation with 1.5 MeV electrons through various annealing stages. By analysis of the EPR spectra, it is shown that the major defects can be identified and the annealing mechanisms determined.

Factors Influencing the Stability of Radiation Defects in Semiconductors

Recent advances in the understanding of radiation damage in semiconductors are discussed and areas of difficulty are indicated. Most attention is focused upon (a) stability of close-pair defects resulting from low temperature irradiation with energetic (0.7 to 5 Mev) electrons, (b) the yield of permanent damage in germanium as a function of temperature, (c) damage of intermediate stability in germanium (anneals at 150°K) which is attributable to non-reorientable divacancies, (d) interstitials in electron bombarded germanium, and (e) low temperature damage in electron bombarded p-type germanium and its transformation by light and heating. The inadequacies of certain of the models are discussed particularly in the case of (e).

Electron Radiation Damage in Semiconductors and Metals

Electron Radiation Damage in Semiconductors and Metals

Book Review: Electron Radiation Damage in Semiconductors and Metals

Book Review: Electron Radiation Damage in Semiconductors and Metals

Symposium on Radiation Damage in Semiconductors, Royaumont, July 1964

The papers and discussions at this symposium showed that radiation damage effects in semiconductors are still far from being completely understood, but that definite progress can be reported.

July 16–18 radiation damage in semiconductors

July 16–18 radiation damage in semiconductors

SECTION OF PHYSICAL SCIENCES: A GRADUATE RESEARCH PROGRAM IN NUCLEAR ENGINEERING AND SCIENCES*

Research problems in reactor physics, nuclear spectroscopy, and radiation effects on materials are discussed. The R.P.I. linac and associated facilities are described. The time dependence of flux on space, energy, and angle transients is being studied. Precision measurements of asymptotic and time- dependent spectra in moderators and subcritical assemblies are reported. Measurements of neutron capture and fission cross sections and the detailed study of certain photonuclear disintegrations are reported as in progress. Some results are given for isotopic assignments of hafnium energy levels. Other programs reported are molecular energy levels and neutron cross sections from low- - energy neutron inelastic scattering, plans for mass spectrometric isotopes laboratories, and radiation damage in semiconductors and thin metal films. (R.E.U.) H03 H029803 No genetic effects were observed in Drosophila on exposure to homogeneous and inhomogeneous magnetic fields of high field strength and gradient. Synergistic effects of magnetic fields in combination with x radiation, starvation, hyperoxia, and hypoxia were also not observed. (auth)