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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.

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.

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.

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.

The physical phenomena associated with the stopping of energetic ions in semiconductor materials have always been a subject which receives great theoretical and experimental interest. Consequently, bombardment of high energy particles and high energy gamma (γ) rays causes potential hazards to these electronic systems. These effects range from degradation of performance to functional failure that can affect the system operations. Such upsets becoming increasingly likely as electronic components are getting more sophisticated while decreasing in size and moves to larger integration. In this paper, the penetration of gamma rays, utilizing Cobalt-60 (Co-60)) into bipolar junction transistor (BJT) is being simulated using the program simulation SRIM. From the findings, it is observed that the penetration of Co-60 ions into the simulated BJT leads to production of lattice defects in the form of vacancies, defect clusters and dislocations. These can alter the material parameters and hence the functional properties of the devices.

Performance and properties of bipolar junction transistor (BJT) devices are affected due to the harsh radiation environment. This report reviews the typical effects occurring in BJT devices due to irradiation with x-rays. The defect parameters on the device tested is obtained by in situ experimental technique. In order to study the self-annealing behaviour in BJTS due to ionizing and displacement modifications, damage efficiencies at different bias current levels are compared. The study reveals that higher gain degradation dispersion occurs at lower bias current level. Damage creation in the BJTs is dominated by the excitation mechanism of valence electron to the conduction band. 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.

Study for defect in semiconductors induced by ionizing radiation has become much more sophisticated in this recent year, driven by the current development in the ongoing miniaturization of silicon (Si) semiconductor industry. In this paper, the damage evolution due to Cobalt-60 (Co-60) is being simulated in nanoscale Silicon layer using SRIM (Stopping and Range of Ions in Matter). SRIM is a computer simulation that uses Monte Carlo method and it contains TRIM (The Range of Ions in Matter) calculation. The SRIM-TRIM calculates the range of ions in matter using collisions of ions-atoms. Besides, the radiation tolerance of the silicon layer is compared when its thickness is scaling down to nano dimension. From the findings, it is observed that the penetration of Co-60 ions into the target silicon layer leads to production of lattice defects in the form of vacancies, defect clusters and dislocations. These can alter the material parameters and hence the properties of the devices. The simulation results also show that nanoscale silicon layer features improved radiation robustness against ionizing radiation, in term of displacement damage.

Studies for introduction of atoms into a solid substrate by bombardment of the solid with ions in the electron-volt (eV) to mega-electron-volt (MeV) energy range have always received great interest. Gallium Arsenide (GaAs) is a basic material for most of the III-V based electronics, and, therefore, lends itself for applications where this is of concern. In this paper, the damage evolution due to photon energy deposition of Cobalt (Co) is being simulated in GaAs material using SRIM (Stopping and Range of Ions in Matter). Besides, TRIM (The Range of Ions in Matter) calculation also gives the amount of nuclear energy deposited in the collisions and recoil events. From the findings of this research, it is found that exposure to high energy photon irradiation causes a degradation of the electrical parameters of GaAs layer and this is mainly caused by the displacement damage.

Space and ground level electronic equipment with semiconductor devices are subjected to the deleterious effects by radiation. This paper is attempted to present the transient and post-irradiation response of optoelectronic devices to gamma (γ) rays utilizing cobalt-60. In situ measurements were made on the devices under test (DUTs) up to a total dose of 60 krad followed by a post-irradiation not in-flux test for eight hours. Current transfer ratio (CTR) with is the vital merit of the optoelectronic system is found to decrease remarkably with the absorbed dose. This degradation is induced by the interaction of the energetic photons from gamma rays via two main mechanisms. The dominant effect is the mechanism by ionization while the secondary is by displacement. This radiation effect is found to arouse either a permanent or temporarily damage in the DUTs depending on their current drives and also the Total Ionizing Dose (TID) absorbed. The TID effects by gamma rays are cumulative and gradually take place throughout the lifecycle of the devices exposed to radiation. The full damage cascade phenomenon in the DUTs is calculated via the simulation.