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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]

In this paper the LiAlSiO4:Ce3+ nanophosphors for different concentration were prepared by low temperature solution combustion method using aloe vera gel as a fuel. The thermoluminescences (TL) was used to characterize the synthesized nanophosphors after gamma irradiation at various doses from a 60Co source. The LiAlSiO4:Ce3+ (1-11 mol %) nanophosphors were irradiated for a total dose 1kGy. Also 7 mol% is irradiated by the different dose such as 1, 3, 6 and 10 kGy which shows good sensitivity for the radiation. The LiAlSiO4:Ce3+ (5 mol%) irradiated with 5 kGy was characterized upto 160 οC at heating rate by 3 and 7 οC/s. The TL analysis using glow curve deconvolution technique was also done for determining different trapping parameters. The obtained results confirm that the synthesized nanophosphors are suitable for dosimetry application. [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]

The total dose effects of 80 MeV C6+ ions on the DC electrical characteristics of Silicon NPN rf power transistors have been studied in the dose range of 100 krad to 100 Mrad. The SRIM simulation was used to understand the energy loss and range of the ions in the transistor structure. The different electrical parameters such as Gummel characteristics, excess base current (ΔIB=IBpost - IBpre), dc forward current gain (hFE), transconductance (gm), displacement damage factor (K) and output characteristics (VCE-IC) were studied systematically before and after irradiation. The significant degradation in base current (IB) and hFE was observed after irradiation. Isochronal annealing study was conducted on the irradiated transistors to analyze the recovery in different electrical parameters. These results were compared with 60C0 gamma irradiation results in the same dose range. [ABSTRACT FROM AUTHOR]

The 200 GHz SiGe HBTs were irradiated with 80 MeV Carbon ions up to a total dose of 100 Mrad to understand the degradation in electrical characteristics. The degradation in the electrical characteristics of SiGe HBTs was also studied by mixed mode electrical stress up to 10,000 s. The electrical characteristics were measured before and after every total dose and after fixed stress time. The normalized peak hFE of the stressed and irradiated SiGe HBTs are compared to estimate the equivalent stress time for a particular total dose. These correlations are drawn for the first time and the results will establish a systematic relation between stress time and total dose. [ABSTRACT FROM AUTHOR]

The effects of 3 MeV proton irradiation on the I-V characteristics of NPN rf power transistors were studied in the dose range of 100 Krad to 100 Mrad. The different electrical characteristics like Gummel, current gain and output characteristics were systematically studied before and after irradiation. The recovery in the I-V characteristics of irradiated NPN BJTs were studied by isochronal and isothermal annealing methods. [ABSTRACT FROM AUTHOR]

Single crystals of nonlinear optical (NLO) L-alanine Sodium Nitrate (LASN) were grown by slow evaporation method. The grown crystals were irradiated by 100 MeV oxygen ions with the cumulative doses of 1Mrad, 6 Mrad and 10 Mrad. The dielectric properties, differential scanning calorimetry (DSC) and second harmonic generation (SHG) of the crystals were studied before and after irradiation. The dielectric constant was found to increase after irradiation. The DSC reveals that the melting point remains unaffected due to irradiation. The SHG efficiency of LASN was found to decrease with increase in radiation dose. [ABSTRACT FROM AUTHOR]

In this paper we present the comprehensive results on the effects of different radiation on the electrical characteristics of different semiconductor devices like Si BJT, n-channel MOSFETs, 50 GHz and 200 GHz silicon-germanium heterojunction bipolar transistor (SiGe HBTs). The total dose effects of different radiation are compared in the same total dose ranging from 100 krad to 100 Mrad. We show that the irradiation time needed to reach very high total dose can be reduced by using Pelletron accelerator facilities instead of conventional irradiation facilities. [ABSTRACT FROM AUTHOR]

The semi-organic non-linear optical (NLO) crystals of γ-Glycine (G), with additives like Ammonium Oxalate (AO), Barium Nitrate (BN) and Potassium Nitrate (PN) were grown by aqueous solution method. The mechanical properties, dielectric constant, dielectric loss, AC conductivity of the grown crystals were studied. Studies confirm that the grown NLO crystals retain the merits of organic (SHG response and flexibility) and inorganic (good hardness) properties. [ABSTRACT FROM AUTHOR]

N-channel depletion metal oxide semiconductor field effect transistors (MOSFETs) were irradiated with 175 MeV Ni3+ ions and Co-60 gamma radiation in the dose range of 100 krad to 100 Mrad. The I-V characteristics of MOSFETs were studied systematically before and after ion and gamma irradiation. The threshold voltage (VTH) of the irradiated MOSFETs was found to decrease with increase in ion and gamma dose. The more degradation was observed in the devices irradiated with Co-60 gamma radiation than irradiated with Ni13+ ions at given total doses. [ABSTRACT FROM AUTHOR]

The dc characteristics of NPN rf power transistors were studied systematically before and after irradiation by 50 MeV Li3+ ions, 100 MeV F8+ ions and 140 MeV Si10+ ions in the dose range of 100 krad to 100 Mrad. The transistor parameters such as excess base current (ΔIB = IBpost-IBpre), dc current gain (hFE), and collector-saturation current (ICSat) were determined before and after irradiation. The base current (IB) was found to increase significantly after ion irradiation and this in turn decreases the hFE of the transistors. Further, the output characteristics of the irradiated devices exhibit the decrease in the collector current at the saturation region (ICSat) with increase of ion dose. [ABSTRACT FROM AUTHOR]

Deep Level Transient Spectroscopy (DLTS) technique is useful tool to study process and radiation induced defects in semiconductor materials and devices. The different types of radiation induced trap levels in the collector-base depletion region of the transistors were studied by DLTS technique. [ABSTRACT FROM AUTHOR]