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In this paper, we present the investigation results of radiation-induced effects in metal-oxide-semiconductor (MOS) doped with moderate amounts of Zinc Oxide (ZnO) as a potential candidate for space-borne application. The samples were fabricated via the sputtering method at a working pressure of 3mTorr and a deposition temperature of 300oC. The ZnO samples were exposed to 1.25-MeV gamma-ray utilizing Co60 source, and their electronic response was measured at ionizing doses ranging from 10 kGy to 300 kGy. A comparative work was performed through finite element method to simulate the electronic response of the PN junction diode due to ionizing radiation. The results indicate that the ideality factor of the MOS diode increases as the ionizing dose increases, rendering it unsuitable for use as a diode. The degradation of the electrical parameters was also simulated, showing the increase in hole concentration. These findings suggest that the ejection of electrons occurred, which agrees with the gamma radiation effects trend. Furthermore, as the intensity of radiation increases, the spatial charge that arises from the separation of hole-electron pairs results in a substantial reduction of the electric field in the central portion of the n-type region. These findings provide insights into the degradation of electrical parameters in MOS devices under gamma radiation and have implications for their use in space-borne applications.

In space, geostationary electronics located within the outer van Allen radiation belt are vulnerable to gamma radiation exposure. In terms of application, implementing an electronic system in a high radiation environment is impossible via conventional engineering materials such as metal alloys as they are prone to radiation damage. Exposure to such radiation causes degradation and structural defects within the semiconductor component, significantly changing their overall density. The changes in the density will then cause electronic failure, known as the single event phenomena. Thus, the radiation response of material must be thoroughly investigated before the material is applied in a harsh radiation environment, specifically for flexible space borne electronic application. In this work, potential candidates for space-borne application devices: zinc oxide (ZnO) and Mg-doped ZnO thin film with a film thickness of 300 nm, were deposited onto an indium tin oxide (ITO) substrate via radio frequency (RF) sputtering method. The fabricated films were then irradiated by Co-60 gamma ray at a dose rate of 2 kGy/hr. The total ionizing dose (TID) effect of ZnO and Mg-doped ZnO thin films were then studied. From the results obtained, degradation towards the surface morphology, optical properties, and lattice parameters caused by increasing TID, ranging from 10 kGy–300 kGy, were evaluated. The alteration can be observed on the morphological changes due to the change in the roughness root mean square (RMS) with TID, while structural changes show increased strain and decreased crystallite size. For the optical properties, band gap tends to decrease with increased dose in response to colour centre (Farbe centre) effects resulting in a decrease in transmittance spectra of the fabricated films.

PM10 (particulate matter with aerodynamic diameter below 10 microns) has always caught scientific attention due to its effect to human health. Predicting PM10 concentration is essential for early preventive measures, especially for cities such as Kota Kinabalu. Temporal data clustering may enhance accuracy of prediction model by group data in time range. However, the necessity of temporal data clustering has yet to be studied in Kota Kinabalu. OBJECTIVE. This research is conducted to compare significance of meteorological and pollutant factors for PM10 variation in clustered and unclustered data. METHODOLOGY. This study is focused in Kota Kinabalu, Sabah. The data for meteorological factors (Ws, Wd, Hum, Temp) and pollutant factors (CO2, NO2, O3, SO2, PM10) from 2003 to 2012 provided by Department of Environment are used for this research. Missing data are imputed using nearest neighbour method before it is clustered by monsoonal clustering. Unclustered and clustered datasets are analysed using principal component analysis (PCA) to check significance of factors contributing to PM10 concentration. FINDINGS. PCA results show that temporal clustering does not have noticeable effect on the variation of PM10 concentration. For all datasets, humidity and x-component wind speed have highest factor loading on PC1 and PC2 respectively. Further statistical analysis by 2-D regression shows that humidity (ρ = -0.60 ± 0.20) and temperature (ρ = 0.63 ± 0.11) have moderate to strong correlation towards PM10 concentration. This may be due to high humidity level and strong negative correlation between temperature and humidity (ρ = -0.91 ± 0.03). In contrast, both x- and y-component wind speed generally show weak correlation towards PM10, with ρ value of 0.09 ± 0.14 and 0.24 ± 0.18 respectively probably because of varying direction of particle dispersion. Fourier analysis further confirms this result by showing that human activity contributes major effect to variation of PM10 concentration.

A case of severe flash flood event affecting Kota Kinabalu (KK) on 17 Jul 2005 is analyzed by means of synoptic analysis using ERA-Interim Reanalysis and NCEP-FNL Data sets. In the synoptic scale, significant amount of precipitation was recorded in Sabah on 16 Jul and 17 Jul 2005. The heavy rainfall was associated to the upper-level ridge and lower-level cyclone observed over the South China Sea. Several low-pressure centers were also noticed over the Philippines Sea which were believed to intensify the heavy rainfall in Sabah. The vertical cross section for divergence along 116°E at Kota Kinabalu also revealed that a significant convergence was observed near the surface and accompanied by a strong updraft of divergence at upper-level. In the mesoscale, the ability of the convection-permitting WRF model to reproduce the convective cells associated with the heavy rainfall event is examined. A triply nested WRF model with the highest resolution of 5-km horizontal grid spacing was integrated with conventional analysis data. The simulation results were validated against observation from TRMM, CHIRPS, and PERSIANN-CDR. The modelled results agree moderately to the observation and fairly well simulated the initiation, intensification, and deceleration of heavy rainfall at nearly the right time except for some mismatch in terms of spatial distribution. The corresponding precipitation amount was also reasonably reproduced in its distribution but slightly overestimated. We also found that the cause of this severe flash flood is rooted to the prolonged heavy rainfall in the KK region induced by Typhoon Haitang.

This study aims to analyse the distribution and factors that control the accumulation of heavy metals in marine sediment from Marudu Bay, Sabah. The sediment samples originated from the various types of rocks, namely ultrabasic rock, basic rock, and chert of ophiolite sequence, and sedimentary rock of the Kudat Formation. A total of 20 sediment core samples were systematically sliced for physico-chemical analysis such as pH value, organic matter (OM), and particle size distribution (PSD). Seven heavy metals are analysed in this research, namely cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), vanadium (V), and zinc (Zn) which is measured using the ICP-OES instrument. Descriptive statistics were used to study the distribution and accumulation of heavy metals from two main stations, namely Sg Karang Station (ST) and Kg Tampakan Station (SK). The results from both stations showed various levels of heavy metal concentration. The average concentration of Mn is between 2.19 mg/kg - 94.77 mg/kg and followed by Cr (0.87 mg/kg - 21.11 mg/kg). For Ni, Zn, Cu, V, and Co, the concentration range were between 0.28 mg/kg - 11.48 mg/kg, 0.94 mg/kg - 6.95 mg/kg, 0.55 mg/kg - 6.01 mg/kg, 0.64 mg/kg - 3.77 mg/kg, and 0.02 mg/kg - 0.85 mg/kg respectively. The result of correlation analysis showed the significant negative relationship between pH with Co, Cr, Ni, Mn, and Zn indicated the increasing concentration in acidic condition. A strong negative correlation between percentage of sand and Co, Cr, Mn, and Ni indicated the decreasing concentration in coarse sediment particle size. However, there was a strong positive correlation between percentage of sand and V due to the association in the carbonate minerals. The Kruskal-Wallis tests showed there were no significant means difference of the percentage of heavy metals based on sample depth and the distance from the shoreline except for V and Mn.

Silicate glass is one of the popular radiation shielding materials due to its abundance on Earth. However, due to fabrication simplicity, tellurite-based optical glass materials became the primary glass network forming, garnering great scientific and technological relevance for their future uses. Previous studies stated that the silicate and tellurite glass system might be employed in shielding applications, with metal oxide concentrations balanced with SiO2 and TeO2 content. The inclusion of SiO2 and TeO2 in the glass composition reduces the impact of radiation. In electron radiation, electron interaction activities with glass are more substantial in the low electron energy area. Meanwhile, the proton attenuation factors of the glass samples are smaller than the electrons. There is no discernible difference in the fast neutron effective removal cross-section (ΣR) values of the glass samples in neutron radiation. In the studies of tellurite glasses for gamma radiation shielding, the photon interaction parameters change as a function of material density. The measurements show that adding TeO2 to glass samples improved the gamma protection characteristics of the glasses. This review aims to explain the various material compositions and discuss a more in-depth analysis of radiation shielding properties in the silicate and tellurite glasses.

The present study examines the impact of meteorological conditions on future surface ozone (O3) over Malaysia region under RCP8.5 and RCP4.5 scenarios. The weather research forecast–community multiscale air quality (WRF-CMAQ) modelling system has been applied for the baseline period (year 2010) and the future day period (years 2050 and 2100) during the winter and summer monsoons. The simulation of WRF agrees well with observation datasets in simulating the surface temperature. However, precipitation did not perform well. The future projection revealed that the surface temperature increased across the Malaysian region, while patterns of total precipitation were varied. The study also identified model deficiencies of WRF-CMAQ in simulating air quality in the Malaysian region. RCP simulations reproduced the observed and reanalysis dataset for O3 mixing ratio with moderate values in statistical analysis. Compared with the present scenario, a small decrease in the O3 concentration was found under RCP8.5 scenario, while a large decrease was found for the RCP4.5 scenario except for the winter monsoon. In 2100, O3 reduced by − 1.4% (− 15.2%) and 4.5% (− 25.8%) during winter (summer) monsoons under the RCP8.5 and RCP4.5 scenarios, respectively. Overall, the decrease in O3 was found to be affected by meteorological change, as well as changes in ozone oxidants such as hydroxyl radical (OH), nitrogen oxides (NOx) and acid nitric (HNO3). Further tightening control measures on anthropogenic emissions to reduce future surface ozone may be unnecessary, since the future ozone mixing ratio did not exceed the Malaysia standard. However, continuous monitoring is vital to ensure efficient air quality management in Malaysia.

A smaller band gap with lower electron-hole recombination is required to ensure good photocatalytic performance of a photocatalyst. This study reveals that the incorporation of graphene oxide (GO) into Engelhard Titanosilicate-10 (ETS-10) forms GO/ETS-10 material with reduced optical band gap of about 2.9 eV, thereby making the GO/ETS-10 material a functional photocatalyst under regions of visible and ultraviolet radiations. Moreover, the results of ultraviolet photoelectron and low-energy inverse photoelectron spectroscopy (UPS-LEIPS) show that GO is a good platform for ETS-10, which significantly lowers the electronic band gap (Eg = 4.005 eV) between the highest occupied (HOMO) and lowest unoccupied molecular orbitals (LUMO) to ease electron transport, significantly reduces the work function (WF = 4.357 eV) to facilitate excitation of electron, and significantly increases the electron affinity (EA = 4.179 eV) to slow down the electron-hole recombination. The results are in good agreement with the empirical photocatalytic degradation of aqueous methylene blue (MB) by the GO/ETS-10 material. Under ultraviolet light irradiation, photocatalytic degradation of MB by the GO/ETS-10 material (as GO/ETS-10/UV-A) shows a similar degradation rate (k1 = 1.6 × 10−3 min−1) in comparison to that under visible light irradiation (as GO/ETS-10/Vis) (k1 = 1.6 × 10−3 min−1), and double the degradation rate in comparison to that in the ETS-10/UV-A system (k1 = 0.7 × 10−3 min−1). Furthermore, the addition of 10 mM of hydrogen peroxide (H2O2) into the photocatalytic system significantly increases the rate of MB degradation with k1 = 4.8 × 10−3 min−1 for the GO/ETS-10/H2O2/UV-A system and k1 = 2.9 × 10−3 min−1 for the GO/ETS-10/H2O2/Vis system. This study illustrates that UPS-LEIPS can be a good technique to predict the performance of a solid photocatalyst, and the GO/ETS-10 material is a good photocatalyst for the degradation of organic pollutants in water.

In the tropics, Langley calibration is often complicated by abundant cloud cover. The lack of an objective and robust cloud screening algorithm in Langley calibration is often problematic, especially for tropical climate sites where short, thin cirrus clouds are regular and abundant. Errors in this case could be misleading and undetectable unless one scrutinizes the performance of the best fitted line on the Langley regression individually. In this work, we introduce a new method to improve the sun photometer calibration past the Langley uncertainty over a tropical climate. A total of 20 Langley plots were collected using a portable spectrometer over a mid-altitude (1,574 m a.s.l.) tropical site at Kinabalu Park, Sabah. Data collected were daily added to Langley plots, and the characteristics of each Langley plot were carefully examined. Our results show that a gradual evolution pattern of the calculated Perez index in a time-series was observable for a good Langley plot, but days with poor Langley data basically demonstrated the opposite behavior. Taking advantage of this fact, the possibly contaminated data points were filtered by calculating the Perez derivative of each distinct air mass until a negative value was obtained. Any points that exhibited a negative derivative were considered bad data and discarded from the Langley regression. The implementation was completely automated and objective, rendering qualitative observation no longer necessary. The improved Langley plot exhibits significant improvement in addressing higher values for correlation, R, and lower values for aerosol optical depth, τa. The proposed method is sensitive enough to identify the occurrence of very short and thin cirrus clouds and is particularly useful for sun-photometer calibration over a tropical climate.

In space, semiconductor devices are vulnerable to various effect of high energy radiation, causing single event upsets (SEUs), damaging or altering the lattice structure of the semiconductor device. The effect of ionizing radiation on metal oxide semiconductor device had been receiving very little attention as most research focus on polycrystalline silicon-based semiconductor. Based on our previous research studies specifically on gamma radiation exposure, the interaction effects of radiation towards ZnO based semiconductors shows changes across all 4 different types of parameter, namely the morphology, structural and optical as well as the electrical properties. As a general classification, morphological change is attributed to the interaction within the crystal lattice, while structural distortion is due to high energy displacement cascade, whereas changes in the optical properties relates to the formation of colour centres (F-centre). The overall parametric changes will then affect the electrical properties as degradation of general parameters will lead to the increase of the ideality factor of the ZnO semiconductor device. The increase of the ideality factor after irradiation is attributed to the production of recombination centres in the space charge region. Furthermore, large values of the ideality factor, obtained after irradiation, point out extrinsic recombination mechanisms where the initial and final states of recombination are located at a lattice imperfection such as a dangling bond or a complex involving impurity atoms and vacancies. Therefore, in this paper a more thorough review of past research on the radiation related studies on ZnO is discussed. This review aims to provide an in-depth discussion on various radiation effects of zinc oxide based semiconductor devices.

Irradiation impact of gamma rays and X-rays on bipolar junction transistors (BJTs) in terms of electronic excitation due to transfer of energy and subsequent ionization, as well as energy transfer to atomic nuclei is studied using in-situ method. Comparison is made on the electrical characteristics of the devices under test (DUT) for various collecting current at two different operating mode. Both temporary and permanent damages in DUTs are found to be induced by energy transfer from the irradiation by gamma-rays and X-rays, depending upon total dose absorbed and current drive. Increased probability of recombination, due to creation of electron–hole pairs at the base region is found to be the most significant radiation damage in BJTs, as it leads to decrease in electron flux reaching the collector region.

Nuclear dispersion is an important aspect in the process of slowing down ions by transferring their momentum to the target atoms and in determining path of the ion. This paper concerns the quantitative evaluation of the mechanism at which helium ions lose their energy when penetrate into a solid and the eventual distribution of the helium ion while stopping inside the Gallium Arsenide compound (GaAs). The first order effects of the atoms of the compound such as the electronic excitation of the atom, the lattice damage incurred to it, as well as the production of phonons in Gallium Arsenide due to the helium ions are also taken into account. The main finding is the mechanism of penetration of helium ions in GaAs, which is affected by the energy, the angle of incidence, and penetration density of the helium ions. It is found out that the energy has major impact than the angle of incidence in the interaction.

Neutron bombardment on semiconductor material causes defects, one such primary physical effect is the formation of displacement defects within the crystal lattice structure, and such defects effectively decrease the mean free path and thus shorten the recombination time. Ionizing radiation causes creation of electron-hole pair in the gate oxide and in parasitic insulating layers of the MOS devices. Calculations show increase of the dark current in depletion region caused by a single neutron. Determination of energy and angular distribution of primary knock on atoms, with 14 MeV neutron irradiation in silicon are presented.

Background and objective: Ozone gas has been used in microorganism treatment and is known as one of the strongest oxidizing agents. The main limitation of ozone is decay rapidly due to its short halflife. In this study, a novel method was established to enhance the production of ozonated water with lower decomposition time. Materials and method: The newly developed prototype was designed with improved technology to increase the kinetic reaction between ozone and water utilizing the parameters of high pressure and continuous flow. Ozonated water produced was examined using dissolved ozone meter with maximum detection of 20 mg L−1. The reaction and decomposition modeling of this system was developed and the dynamic structure of produced ozonated water was investigated using Raman spectroscopy. Results: The findings showed that the newly developed prototype facilitates a higher concentration of ozonated water with an ozone transfer rate of 2.5 L min−1 and a lower decomposition rate with an average half-life 200 min. The results obtained from Raman spectroscopy showed the increases in ozonated water concentration leading to a decrease in the intensity of Raman peak, more likely approaching the Raman intensity of distilled water. Conclusion: This system was proven to be efficient in producing ozonated water at high volume and concentration with longer half-life which suits the domestic and industrial application requirements.

In this research, n-ZnO/p-CuGaO2 based semiconductor devices were fabricated and exposed to gamma rays with increasing total ionizing dose (TID) and neutron fluence at different flux. Based on the I-V properties, the decrease in the turn-on voltage of the diode is noticeable with increasing radiation dose for both gamma and neutron flux exposure. The maximum turn-on-voltage of the fabricated diode was shown to be 1.5 V. Exposure towards gamma, shows that the turn-on is increased to 4.7 V at 200 kGy. However, the effect of neutron flux at 6.5x1015 n/cm2 shows a small significant effect on the turn on voltage of 1.7 V after irradiation. Results show moderate mitigation towards irradiation, indicating that n-ZnO/p-CuGaO2 thin film is capable of withstanding harsh radiation environment while still retaining its semiconductor as the changes in band gap ranges between 3 eV to 4 eV at post-irradiation.

Silicon is always the dominant semiconductor material of the modern semiconductor industry. This is as silicon can retain its semiconductor characteristics even at a higher temperature while the other semiconductor materials can't. However, when a silicon device is exposed to a flux of energetic radiation or particles, the effects from the radiation and the induced secondary particles can cause several degradation of the device performance. For the purpose of investigate the resultant effects from the bombardment of neutrons and the behavior of secondary charged particles in the silicon model, the neutron displacement defect was measured in situ and then followed by the simulation based on Monte Carlo method. The bombardment of neutron in the silicon model produce at least three secondary particles, which are alpha ˸α˹ particles, proton (p) particles and silicon recoil atoms, through the reactions of ˸̾˼α˹˼˰˸̾˼̀˹˰and neutron scattering respectively. The kinetic energy and range of these charged particles are different among themselves, and thus the probability of hitting and degradation effects in the silicon materials are varies. The simulation calculation showed that ˸̾˼α˹˰reaction induced soft error cross section of about 8.7 x 10-14 cm2 and for recoil atoms, it is about 2.9 x 10-15 cm2. There was no error of the silicon device configuration induced by proton particles until 1010 n/cm2.neutron fluence. It can be concluded that the largest portion of error in the silicon model is induced by the secondary alpha ˸α˹ particles.

Poly(triarylamine) is one of the well-known organic materials and has several advantaged such as stable in ambient and require low-temperature annealing steps. A series of PTAA thin films were deposited at 1000 rpm to 3000 rpm on a glass substrate by spin coating. The structural and optical properties of the organic p-type semiconductor Poly(triarylamine) at the different spin rate were investigated. All the thin films exhibit approximately over 90% transmittance and the estimated band gap in the range of 3.01‐3.14 eV. The increasing of the spin rate results in the decreasing of the thickness and this relation obeys the power law relation of the form h ∝ ω−3/2, while the root mean square (RMS) of the films became more uniform as the spin rate increased.

The application of optical based instrument in particulate matter monitoring has gained interest among researchers in recent years due to their high degree automation in providing real time reading of particulate matter concentrations. Such instrument usually comes in compact form making it compatible for in-situ monitoring especially for dense monitoring network. Theoretically, optical based instrument is unable to measure the mass concentration of particulate matter which is the key parameter in air quality monitoring. Instead, the mass concentration is calculated based on particle size distribution under assumptions that all particles is spherical using a known density. This being said, the accuracy of the reported mass concentration by optical instrument can be easily deteriorated if one of these assumptions is violated. Therefore, there is a need for a thorough evaluation on the particle to mass conversion factor in order to improve the accuracy of the reported mass concentrations by an optical instrument. In this study, the reported mass concentration from an optical based instrument as a function of particle distribution through random air sampling was investigated. The obtained data was then used to develop a parametric model for calculation of particulate mass concentration based on particle count distribution. The model developed was evaluated at several site and reported a good accuracy with high correlation (R2 > 0.97) in estimation of mass concentration.

Zinc Oxide (ZnO) thin films have been deposited onto an ITO glass by RF sputtering method in a controlled condition followed by a layer of Poly(triarylamine) as an electron acceptor to form a hybrid-heterojunction thin film. In this work, Poly(triarylamine) is deposited by using spin coating method at different spin rate ranging from 1000 RPM to 5000 RPM. The correlation between the structural and optical properties of this hybrid heterojunction were investigated. The crystallographic structure of ZnO and PTAA is analysed by obtaining its Full width half maximum and grain size value by using X-ray diffractometer. UV-Vis result strongly reveal that all the thin films exhibits high transparency (>80%) in visible region with wide band gap of 3.38 eV for ZnO and 3.1 eV for PTAA at 5000 RPM sintering. Surface morphology of the hybrid film is observed using an advance material microscope (HIROX) with 3 different lenses of low range, mid-range and high range. It is shown that, as the RPM speed is increasing the distribution of PTAA on the ZnO layer is smoother and uniform. The correlation value obtained for grain size and band gap is 0.9344 and 0.9136. Thus, concluded that grain size and bandgap of device is highly correlated.

This paper reviews typical effects occurring in bipolar junction transistors (BJTs) due to gamma (γ) rays irradiation. The detrimental consequences of this interaction can be categorized into two: the transfer of energy to electrons due to ionization and electronic excitations; and also the transfer of energy to atomic nuclei. The radiation damage induced by this interaction was studied using in situ method by comparing the currentvoltage characteristics of the devices under test (DUTs) at different biased collecting current and operating modes. The high energy from gamma radiation is found to induce both temporarily and permanent damage in the DUTs depending on the current drive and total dose absorbed. The most significant radiation damage in the BJT is the creation of electron-hole pairs which increases the probability of recombination at the base region of BJTs. The DUTs are found to exhibit minor annealing effect at post-irradiation and the results also show that devices operating in higher bias current are more capable of withstanding the effect by gamma radiation.

Electronic device that subjected to various effects by radiations can cause small interferences such as noises in the circuit. These effects are especially critical in operating environment such as outer space, where radiation comes in stronger and more frequent. In this research, analytical study on the effects of ionizing radiation induced by 60Co gamma (γ) rays in bipolar junction transistor (BJT) devices had been performed. It was found that the high energy of the radiation allows more valence electrons to be excited to the conduction band in the BJT. This leads to the production of a large number of excited atoms and increases the holes in the valence band. The increase of holes in the base region due to trapping will increase the probability of recombination and reducing the number of electrons that reaches the collector region. This ionizing radiation effect was found to arouse either a permanent or temporarily damage in the devices depending on their current drives and total dose absorbed.

Radiation effects on Gallium Arsenide (GaAs) have been tested by exposing samples to Cesium-137 (137Cs) gamma rays. Gallium Arsenide is a basic photonic material for most of the space technology communication, and, therefore, lends itself for applications where this is of concern. Monte Carlo simulations of interaction between direct ionizing radiation and GaAs structure have been performed in TRIM software, being part of SRIM 2011 programming package. An adverse results shows that energy dose does not govern the displacement of atoms and is dependent on the changes of incident angles and thickness of the GaAs target element. At certain thickness of GaAs and incident angle of 137Cs ion, the displacement damage is at its highest value. From the simulation result, it is found that if the thickness of the GaAs semiconductor material is small compared to the projected range at that particular incident energy, the energy loss in the target GaAs will be small. Hence, when the depth of semiconductor material is ...

Microsystems, both in space and ground level, will use systems with III-V semiconductors and devices of nanoscale. Vulnerability of this system towards the radiations warrants extra care to be taken. Therefore, appropriate test and analysis to assure the hardness (radiation resistance) of components to be used in various radiation environments is necessary. In this paper, the defect generated in the interaction of alpha (α) particles and silicon (Si) semiconductor material is simulated using SRIM (Stopping and Range of Ions in Matter). The induced defects are in the form of vacancies, defect clusters and dislocations. Besides, the defect is found influencing the kinetic processes that occur both inside and outside the cascade volume. The radiation tolerance between the conventional scale and nanoscale thickness of silicon layer is also being compared. From the findings, it is observed that when the thickness of silicon layer is scaled down, defect that induced by the energy deposition of -particles is significantly lesser. This means that nanoscale silicon layer features improved radiation robustness towards the deposition of energetic ions.

In this research, optoelectronic devices consisted of an infrared light emitting diode and a phototransistor with no special handling or third party-packaging were irradiated to ionizing radiation utilizing x-rays. It was found that the devices under test (DUTs) undergo performance degradation in their functional parameters during exposure to x-rays. These damaging effects are depending on their current drives and also the Total Ionizing Dose (TID) absorbed. The TID effects by x-rays are cumulative and gradually take place throughout the lifecycle of the devices exposed to radiation.

Neutron radiation causes significant changes in the characteristics of MOS devices by the creation of oxide-trapped charge and interface traps. The degradation of the current gain of the GF4936 dual n-channel depletion mode MOS transistor, caused by neutron displacement defects, was measured using in-situ method during neutron irradiation. The average degradation of the gain current is 35 mA at maximum fluence of 2.0 × 1010 n/cm2 while with an average of 25 mA at minimum fluence of 5.0 × 108 n/cm2. The change in channel current gain increased proportionally with neutron fluence, meanwhile drain saturation current decreased proportionally with the neutron fluence.