بررسی خواص الکتروفیزیکی واریستورهای ترکیبی تهیه شده براساس گالیم آرسنید و پلیمر(پلی آنیلین)
/ساجده محمدی عارف
: دانشکده فیزیک
۱۸۳ص
چاپی
درجه دکتری
در رشتهی فیزیک - گرایش حالت جامد
۱۳۹۱/۱۱/۱۵
تبریز
.semoctuo etisoppo ni stluser lavretni emit gnilaenna eht gnisaercni ,esaerced ot tnerruc egakael eht dna esaercni ot egatlov nwodkaerb eht sesuac lavretni emit detimil rof erutarepmet tnatsnoc a ta gnilaenna hguohT)3
.Electrical and electronical systems are sensitive to various surges. Internal overvoltage transients or external electrostatic discharges cause irreparable damages to the systems. As a result, the electronic devices should be protected by any means. A practical method to overcome these surges is to use smart semiconductors to protect systems against overvoltages. These nonlinear variable resistors, whose nonlinear electrical properties make them competent to sense and limit transient surges repeatedly and quickly, are called varistors. In order to achieve the main goal of this project which is introducing varistors with lower breakdown voltages, first, the role of reducing the thickness of the composite zinc oxide varistors and then the effect of gallium arsenide replacement were investigated. The results show that although grain boundary structure of varistor is responsible for the non-linear behavior in both types, breakdown voltages of gallium arsenide-polymer varistors are distinctively lower than that of zinc oxide-polymer varistors. Obtained results for zinc oxide-polymer varistors, which were prepared using solution-casting method, can be summarized as follows: by increasing the amount of zinc oxide in the varistors' structure, their breakdown voltage, hysteresis and absorption increase; while their nonlinear coefficient, leakage current as well as their optical bandgap decrease
swollof sa era stluser ehT .snoitidnoc krow dna sisehtnys sa llew sa stneidergni fo tnuoma eht fo noitcnuf a sa deiduts erew scitsiretcarahc rieht ,srotsirav remylop-edinesra muillag roF: