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Superjunction MOSFETs used in aircraft and spacecraft can be exposed to high-density and high-energy gamma-ray radiation environments. Commercial superjunction MOSFETs were irradiated with gamma rays in their packaged state and their static and dynamic characteristics were measured. From the double pulse test, the switching waveforms of the devices were extracted as a function of irradiation dose, and gate oscillations were observed. To provide an accurate physical analysis, a five-contact TCAD model was used and compared with the actual data. In the simulation, by dividing the gate into the gate-to-source and the gate-to-drain, and the source into the ${n}^{+}$ and the ${p}^{+}$ , we identified the parasitic capacitance characteristics of the device and analyzed the gate oscillations.

Atomic layer deposition (ALD) is a promising nanomaterial synthesis technique due to its excellent confomality over complicated nanostructure. We fabricated ALD semiconducting oxide/semiconductor core-shell nanowire array and characterized the device performances as a photodiode. Si nanowires array with about 100~300 nm diameter were prepared using electroless etching technique. Nitrogen doped ALD ZnO was carried out using diethylzinc (DEZ) and diluted NH4OH various growth temperature. We measured responsivity and external quantum efficiency of the fabricated device as a function of wavelength of incident light and compared with thin film based photodiode. For NW array device, the photocurrent density and responsivity were significantly enhanced compared to thin film based device. Also, by combining self-assembly process, well ordered core-shell ZnO/Si nanowire arrays were prepared. The device performance made of ordered core-shell NW arrays was significantly enhanced. In addition, ZnO homojunction NW photodiode as well as ALD TiO2 outer shell NW photodiodes were fabricated and their device characterizations were compared to the planar type device.

Atomic layer deposition (ALD) is a promising nanomaterial synthesis technique due to its excellent confomality over complicated nanostructure. We fabricated ALD semiconducting oxide/semiconductor core-shell nanowire array and characterized the device performances as a photodiode. Si nanowires array with about 100~300 nm diameter were prepared using electroless etching technique. Nitrogen doped ALD ZnO was carried out using diethylzinc (DEZ) and diluted NH4OH various growth temperature. We measured responsivity and external quantum efficiency of the fabricated device as a function of wavelength of incident light and compared with thin film based photodiode. For NW array device, the photocurrent density and responsivity were significantly enhanced compared to thin film based device. Also, by combining self-assembly process, well ordered core-shell ZnO/Si nanowire arrays were prepared. The device performance made of ordered core-shell NW arrays was significantly enhanced. In addition, ZnO homojunction NW photodiode as well as ALD TiO2 outer shell NW photodiodes were fabricated and their device characterizations were compared to the planar type device.