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The solution combustion synthesis (SCS) method has been used to prepare strontium oxide [SrO2] nanoparticles using strontium nitrate [Sr (NO3)2] as an oxidizer. In order to study the effects of different fuels on the synthesis of SrO2 nanoparticles, different fuels like urea [CH4N2O], citric acid [C6H8O7] and glycine [C2H5NO2] were used. The synthesized nanoparticles were subjected to various characterization techniques such as X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy and UV Visible (UV-Vis) spectroscopy for analysing the structural and optical properties of synthesized samples. The XRD result confirms that the samples are crystalline in nature and the crystallite sizes were found to be 41.90 nm, 47.37 nm and 44.30 nm for CH4N2O, C2H5NO2 and C6H8O7 based SrO2 respectively. The FTIR results shows that there is bending and stretching of bonds because of H-O-H, −OH, and C=O groups. The bandgap (Eg) of the synthesized samples was calculated using UV-Visible spectra and are found to be 5.21 eV, 5.97 eV and 5.89 eV for SrO2 synthesized using CH4N2O, C2H5NO2 and C6H8O7 respectively. The results show that the SrO2 using C2H5NO2 has more bandgap and SrO2 synthesized using C2H5NO2 has more crystallite size. [ABSTRACT FROM AUTHOR]

A simple solution combustion route was adopted to synthesize monoclinic bismuth oxide (α-Bi2O3) nanoparticles using bismuth nitrate pentahydrate [Bi (NO3). 5H2O] and citric acid [C6H8O7] as oxidizer and fuel respectively. In order to study the effect of irradiation, the precursor solution and also the nanoparticles of Bi2O3 have been irradiated with 25 kGy of 60Co gamma radiation. The obtained unirradiated, precursor solution irradiated and irradiated α-Bi2O3 nanoparticle samples were characterized using various techniques to study the change in the properties due to 60Co gamma radiation. The X-ray Diffraction (XRD) analysis was carried out to study the structural properties and Fourier Transform Infrared Spectroscopy (FTIR) was carried out to study the optical characteristics of the synthesized samples before and after irradiation. The crystallite size calculated using XRD results was found to increase with the irradiation compared to unirradiated sample indicating the increase in crystallinity of the sample. The FTIR spectra reveals the stretching vibrations of the bonds present in the sample and there is no significant change in the vibrational frequencies of the sample with irradiation. [ABSTRACT FROM AUTHOR]

The total dose effects of 10 MeV electron on the dc electrical characteristics of NPN bipolar junction transistors (BJT) were investigated in the dose range from 100 krad(Si) to 100 Mrad(Si). The key electrical parameters like Gummel characteristics, excess base current (ΔIB = IBpost − IBpre), dc current gain (hFE), output characteristics(IC−VCE) and collector saturation current (ICSat) were characterized in-situ during irradiation. After electron irradiation the base current (IB) was found to increase significantly after irradiation and in turn decreases the hFE. The collector saturation region (ICSat) was found to decrease with increase in the radiation dose. The electron irradiated results obtained are compared with Co-60 gamma irradiation in the same dose range. The observed degradation in the key electrical characteristics of the transistor is mainly due to radiation induced generation-recombination (G-R) centers in emitter-base (E-B) spacer oxide and point defects in the transistor structure. The degradation for Co-60 gamma irradiation was significantly less when compared to 10 MeV electron irradiated transistor. [ABSTRACT FROM AUTHOR]

Silicon-Germanium heterojunction bipolar transistors (SiGe HBTs) were irradiated with 60Co gamma radiations at different dose rates up to 10 Mrad of total dose. The DC electrical characteristics such as Gummel characteristics, excess base current (ΔIB), current gain (hFE), neutral base recombination (NBR) and output characteristics (IC−VCE) were studied before and after irradiation. The important parameters such as IB and hFE were found to degrade after irradiation. Gamma irradiations at varying dose rates are found to produce drastically different degradation signatures at the different oxide interfaces. The degradation is more for SiGe HBTs irradiated at dose rate of 30 rad/s. [ABSTRACT FROM AUTHOR]

The effects of high energy ions on the electrical characteristics of silicon-germanium heterojunction bipolar transistors (SiGe HBTs) were studied in the total dose of ranging from 600 krad to 100 Mrad (Si). The two generations (50 GHz and 200 GHz) of SiGe HBTs were exposed to 50 MeV lithium, 75 MeV boron and 100 MeV oxygen ions. The electrical characteristics of SiGe HBTs were studied before and after irradiation. The SiGe HBTs were exposed to 60Co gamma radiation in the same total dose. The results are systematically compared in order to understand the interaction of ions and ionizing radiation with SiGe HBTs. [ABSTRACT FROM AUTHOR]

NPN rf power transistors and N-channel depletion MOSFETs are irradiated by different high energy swift heavy ions and 60Co gamma radiation in the dose range of 100 krad to 100 Mrad. The damage created by different heavy ions and 60Co gamma radiation in NPN rf power transistors and N-channel depletion MOSFETs have been correlated and studied in the same dose range. The recoveries in the electrical characteristics of different swift heavy ions and 60Co gamma irradiated devices have been studied after annihilation. [ABSTRACT FROM AUTHOR]

The SiGe HBTs were irradiated with 80 MeV Carbon ions up to 100 Mrad of total dose and were subjected to mixed mode (MM) electrical stress. The DC electrical characteristics were studied for irradiated and MM stressed SiGe HBTs. The base current (IB) of the irradiated SiGe HBTs was significantly increased after 100 Mrad of total dose and in turn, decrease the current gain (hFE). A significant recovery in IB and hFE was observed for ion irradiated SiGe HBTs after MM stress. The recovery in electrical characteristics of the irradiated SiGe HBTs is mainly due to the raise in the junction temperature. [ABSTRACT FROM AUTHOR]

The NPN transistors were irradiated with 80 MeV Nitrogen ion in the dose range from 100 krad(Si) to 100 Mrad(Si). The different electrical characteristics like Gummel characteristics, current gain(hFE) and output characteristics(IC-VCE) were studied before and after irradiation. After nitrogen ion irradiation a significant increase has been observed in the collector current (IC) along with increase in base current (IB). The hFE of the transistors decreased drastically after ion irradiation. Moreover, the output characteristics of the irradiated transistor show that the collector current (IC) in the saturation region (ICsat) decrease with increase in the ion dose. [ABSTRACT FROM AUTHOR]