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In our work, insights into the total dose response and native point defect behavior in the Al2O3 gate dielectric during irradiation were gained by gamma-ray irradiation experiments and first-principles calculations. It is found that the O vacancy (VO) can act as a hole trap in the Al2O3 gate dielectric during irradiation, leading to the negative shift of the capacitance–voltage (C–V) curves of the Al2O3-based metal–oxide–semiconductor (MOS) structure. Our calculations show that the neutral defect VO becomes a +2 charged center after irradiation, and the positively charged VO is a kind of conductive path for electrons, which contributes to an increase of the leakage current in the irradiated MOS capacitors. Additionally, the trapped holes are accumulated with irradiation doses, which can lower the barrier height of the Al2O3 gate oxide and further cause the increase of the leakage current. The other native point defects in the Al2O3 layer, such as aluminum vacancy (VAl), aluminum interstitial (Ali) and oxygen interstitial (Oi), only act as fixed charge centers during irradiation. Net negative charges existing in the Al2O3 layers before irradiation are mainly induced by the negatively charged defects of VAl and Oi.

We have fabricated surface plasmon modulated nano-aperture vertical-cavity surface-emitting lasers (VCSELs) from common 850 nm VCSELs using focus ion beam etching with Ga+ ion source. The far-field output power is about 0.3 mW at a driving current of 15 mA with a sub-wavelength aperture surrounded by concentric periodic grooves. The enhancement of transmission intensity can be explained by diffraction and enhanced fields associated with surface plasmon. This structure also exhibits beaming properties.

In order to study total dose radiation effects of PbZrxTi1-xO3 (PZT) film made with the pulsed excimer laser deposition (PLD) technique, hysteresis loops and capacitance-voltage (C-V) curves of PZT film capacitors have been measured before and after gamma-ray irradiation. The results show that, in a range of 0-2 x 10(5) Gy (Si), with increasing total dose, the remanent polarization 2P(r) increased while dielectric constant epsilon decreased. This can be explained by charges trapped by some defects during irradiation.

(PTO/YBCO) and (PZT/ YBCO) structures were fabricated on and substrates by the pulsed excimer laser deposition (PLD) method, respectively. In order to investigate total dose radiation effects on the Au/PTO/YBCO and Au/PZT/YBCO ferroelectric (FE) capacitors, the capacitance-voltage (C-V) and the retained polarization properties of the capacitor were measured before and after -ray irradiation. The results showed that, with the increment of the dose, the retained polarization and the dielectric constant of the FE capacitors decreased; but the absolute value of the negative and positive coercive fields of the PZT capacitor increased while that of the PTO capacitor decreased. The results have been interpreted by radiation-induced positive charges and the defect trap model.

ions with different energies and doses were implanted into SIMOX (separated by implantation of oxygen) materials to improve their irradiation hardness characteristics. Capacitors were fabricated on the SIMOX material after removing the top silicon layer. The high-frequency C-V characteristics of the capacitors after irradiation with -rays were investigated. It is found that the process of implantation can effectively improve the total-dose irradiation hardness of the buried oxide (BOX) layer of the SIMOX materials. In addition, with the change of dose and energy of the implantation, the distribution of F in the SIMOX material was also changed; in particular, for the dose of and 90 keV implantation, a nearly uniform fluorine doping is produced in the BOX layer upon annealing.

In order to investigate the total dose radiation effects of ferroelectric (FE) capacitors, Pt/PbZr0.52Ti0.48O3/Pt (Pt/PZT/Pt) and Au/PbTiO3/YBa2Cu3O7-δ(YBCO) capacitors were fabricated by pulsed excimer laser deposition (PLD) on Si(100) and SrTiO3(001) substrates, respectively. The capacitance-voltage (C-V) curve and hysteresis loops properties of the capacitors were measured before and after γ-ray irradiation. The results show that, with the increment of the total dose, the remanent polarization and the coercive field of the PZT capacitors did not decrease, but increased while the dielectric constantεdecreased; the degradation of theεof the PbTiO3capacitors is similar to that of the PZT capacitors, but the remanent polarization and the coercive field decreased gradually. The results have been interpreted by radiation-induced positive charges and the traps of defects theory.