ИМПУЛЬСНЫЕ ХАРАКТЕРИСТИКИ КРЕМНИЕВЫХ СТРУКТУР С N-P ПЕРЕХОДОМ, ОБЛУЧЕННЫХ ПРОТОНАМИ

Abstract

Currently, methods are being actively developed to create semiconductor structures with desiredproperties by irradiation with ionizing particles (radiation defect engineering). The interactionof radiation defects with impurities, dislocations and other structural defects causes a change in theproperties of semiconductors and semiconductor devices. Irradiation with protons makes it possibleto controllably create radiation defects with a distribution maximum in a pre-calculated region. Theaim of this work is to analyze the effect of irradiation with low-energy protons on the impulse characteristicsof silicon structures with an n+-p junction. The task is to determine the effective lifetime  ofcharge carriers in the space charge region (SCR) of the n+-p junction. The n+-p-p+-structures madeof silicon grown by the Czochralski method, irradiated from the side of the n+-layer by a low-energyproton flux at sample temperatures of 300 K and 83 K were studied. To measure the impulse characteristics,bipolar rectangular voltage pulses with a constant amplitude of 10 mV and a frequency of1 MHz were used. The experimental data are explained using models of nonstationary charge carriertransport in inhomogeneous semiconductors and the formation of radiation defects in silicon underthe action of protons. Depth distributions of the average number of primary radiation defects arecalculated: interstitial silicon, vacancies, divacancies created by one proton per unit length of theprojective path. It is shown that irradiation with protons with a dose of 1015 cm2 and an energy of40 keV does not change the value of , but with an energy of 180 keV creates a region with an effectivelifetime of 5.5108 s in the SCR of the n+-p junction.