0000000000383067
AUTHOR
A. Pirojenko
Particle detectors made of high-resistivity Czochralski silicon
We have processed pin-diodes and strip detectors on n- and p-type high-resistivity silicon wafers grown by magnetic Czochralski method. The Czochralski silicon (Cz-Si) wafers manufactured by Okmetic Oyj have nominal resistivity of 900 O cm and 1.9 kO cm for n- and p-type, respectively. The oxygen concentration in these substrates is slightly less than typically in wafers used for integrated circuit fabrication. This is optimal for semiconductor fabrication as well as for radiation hardness. The radiation hardness of devices has been investigated with several irradiation campaigns including low- and high-energy protons, neutrons, g-rays, lithium ions and electrons. Cz-Si was found to be more…
Experimental Linear Energy Transfer of Heavy Ions in Silicon for RADEF Cocktail Species
Experimental linear energy transfer values of heavy ions in silicon are presented with comparison to estimations from different semi empirical codes widely used among the community. This paper completes the experimental LET data for the RADEF cocktail ions in silicon.
Radiation hardness of Czochralski silicon, Float Zone silicon and oxygenated Float Zone silicon studied by low energy protons
Abstract We processed pin-diodes on Czochralski silicon (Cz-Si), standard Float Zone silicon (Fz-Si) and oxygenated Fz-Si. The diodes were irradiated with 10, 20, and 30 MeV protons. Depletion voltages and leakage currents were measured as a function of the irradiation dose. Additionally, the samples were characterized by TCT and DLTS methods. The high-resistivity Cz-Si was found to be more radiation hard than the other studied materials.
The effect of oxygenation on the radiation hardness of silicon studied by surface photovoltage method
The effect of oxygenation on the radiation hardness of silicon detectors was studied. Oxygen-enriched and standard float-zone silicon pin-diodes and oxidized samples were processed and irradiated with 15-MeV protons. After the irradiations, the surface photovoltage (SPV) method was applied to extract minority carrier diffusion lengths of the silicon samples. Adding oxygen to silicon was found to improve the radiation hardness of silicon. The effect was visible in minority carrier diffusion lengths as well as in reverse bias leakage currents. The suitability of SPV method for characterizing irradiated silicon samples was proved.
Utilisation of a sputtering device for targetry and diffusion studies
A novel device for versatile sputtering applications is described. The apparatus design is realised for fulfilling the demands of both nuclear physics experiment target production and serial sectioning in solid-state diffusion studies with radiotracers. Results of several tests are reported, characterising the devise performance in these two differing applications.
Annealing study of oxygenated and non-oxygenated float zone silicon irradiated with protons
Abstract Introducing oxygen into the silicon material is believed to improve the radiation hardness of silicon detectors. In this study, oxygenated and non-oxygenated silicon samples were processed and irradiated with 15 MeV protons. In order to speed up the defect reactions after the exposure to particle radiation, the samples were heat treated at elevated temperatures. In this way, the long-term stability of silicon detectors in hostile radiation environment could be estimated. Current–voltage measurements and Surface Photovoltage (SPV) method were used to characterize the samples.