Based on the mechanism of spoof surface plasmon polaritions (spoof SPPs), a kind of microwave bandpass filter is presented in both theory and experiment, which is realised by a periodic subwavelength metallic Domino array. The transmission bandwidth of spoof SPPs is controllable by designing the geometric parameters of the periodic structure. Simulation and experimental results of the spoof SPPs agree well with each other and verify the feasibility in bandpass filter applications.Introduction: The periodic structure has been utilised in microwave and optical component applications in the past [1], such as the reflection mirror, the DFB laser, the light beam coupler in the optical regime, and the bandstop filter, leaky wave antenna at microwave frequencies [2]. In 2004, Pendry put forward a concept of spoof surface plasmon polaritons (SPPs) in the low frequency band using a subwavelength periodic hole on the surface of the metal to increase penetration depth [3], and the working frequency is controllable by the geometric parameters of the structure. The spoof SPPs in the microwave regime have been verified theoretically and experimentally in [4] and [5], and the mechanism of electromagnetic field confinement of the spoof SPPs is studied in [6].In this Letter, we put forward a new kind of bandpass filter in X-band based on the principle of spoof SPPs constructed by the periodic subwavelength Domino structure. The modal field of the guided mode in the Domino structure is almost constant inside the structure. By adjusting the lattice constant and the height of the Domino, we can control the transmission bandwidth and transmission efficiency. Such a structure can be applied in high power filter components.

Low voltage cathodoluminescent characteristics of ZnGa2O4 phosphor grown by rf magnetron sputtering have been investigated from 300 to 700 nm. The effects of substrate heating and annealing treatment on the luminescent characteristics are also studied. A blue cathodoluminescent emission peaked at 470 nm is observed. Better luminescent properties are achieved on the films which have crystal structure with a standard powder x-ray diffraction pattern of ZnGa2O4. The effect of the strength of the ligand field on the resultant energy levels for the ZnGa2O4 phosphor is investigated. Low-voltage phosphor films with excellent cathodoluminescent characteristics have been successfully developed in this research.

A much higher leakage current, a lower breakdown effective field, a poorer charge-to-breakdown, and worse stress-induced leakage current are observed in ultrathin 30 Å oxides even at a low Cu contamination of 10 ppb. The strong degradation of the ultrathin gate oxide integrity can be explained by the tunneling barrier lowering and the increased interface trap tunneling due to the presence of Cu in the oxide and at the oxide-Si interface.Cu contamination 1-7 has attracted much attention in advanced high-speed complementary metal oxide semiconductors ͑CMOS͒ circuits using Cu metallization. The Cu contamination, which may come from either the front surface Cu interconnects or the back-side surface contaminated by the Cu process, may precipitate at the Si/SiO 2 interface 5,7,8 or form a silicide by a reaction with Si. The Cu contamination can degrade metal oxide field effect transistor's ͑MOSFETs͒ performance by increasing the leakage current at the source-drain junction, shifting the threshold voltage, and increasing the subthreshold swing. 8,9 The Cu contamination may also degrade the gate oxide integrity by reducing the breakdown electric field at high contamination levels, 2 but has little effect on the gate area oxide breakdown at low contamination levels. 1 However, most of the reported Cu contamination studies are focused on relatively thick oxides. In this paper, we have examined the gate oxide integrity 10-12 of Cu-contaminated ultrathin ϳ30 Å oxides used for an 0.18 m generation. In contrast to previous reports on thick oxides, we have found severe degradation of the gate oxide integrity for these ultrathin ϳ30 Å oxides. Compared with the control sample, the contaminated oxides show higher direct and Fowler-Nordheim ͑F-N͒ tunneling currents, lower breakdown electric field, poorer charge-to-breakdown distribution (Q BD ), and worse stress-induced leakage current ͑SILC͒, even at a low Cu contamination level of 10 ppb. This is probably due to the presence of Cu within both the oxide and the Si-oxide interface, which effectively lowers the tunneling barrier and increases the SILC. ExperimentalStandard 4 in. p-type Si ͑100͒ wafers with a typical resistivity of ϳ10 ⍀ cm were used in this study. The preoxidation cleaning of the wafers was performed by a modified RCA clean, followed by HF dipping, and spin drying. Device isolation was formed by growing and patterning the 3000 Å thick field oxide. Then the ϳ30 Å gate oxide was grown at 900°C in dry oxygen diluted with nitrogen. The oxide thickness was measured by ellipsometry and high frequency C-V measurements under accumulation. The gate electrode was formed by depositing a 3000 Å poly-Si with subsequent phosphorus doping by POCl 3 . The standard aluminum contact was formed by thermal evaporation, and MOS capacitors of 100 ϫ 100 m were fabricated. The Cu contamination was introduced by dipping the devices for 1 min into a CuSO 4 solution with a concentration of 10 ppb or 10 ppm, and the contaminated wafer was then annealed at 400°C in a nitrogen gas ambient. Figur...

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ZnGa204 films have been prepared by radio frequency (RF) magnetron sputtering at various total pressure, RF power, and substrate temperatures. Microstructure and crystallographic orientation were characterized by x-ray diffraction. Surface morphologies were observed by scanning electron microscope. In addition, cathodoluminescence (CL) measurement was employed to observe the emission spectra of ZnGa204 films. The influences of various deposition parameters on the properties of grown films were studied. The optimum substrate deposition temperature for luminous characteristics was about 500~ in this investigation. A blue cathodoluminescent emission peaked at 470 nm was observed. Good luminescent properties were observed in the films which exhibit the standard ZnGa204 x-ray diffraction pattern.