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We investigated the interface structural properties of direct bonded SiCN substrate using neutron reflectometry (NR). NR results suggest that direct bonded SiCN requires annealing process immediately after bonding process, because of water penetration into non-annealed bonded interface.

In this paper, we propose a 3-D chiral metamaterial comprising of a high-K dielectric cube and metallic mesh in the microwave region. Our numerical results show that the metamaterial has dispersionless optical activity and an impedance matching to free space, resulting in broad polarization rotation and low reflectance.

In this paper, a polarization-plane-controllable beam-scanning leaky-wave antenna based on pseudo-traveling-wave resonance is proposed and demonstrated by using nonreciprocal metamaterials. The antenna is composed of a ferrite-microstrip-line-based nonreciprocal composite right/left-handed transmission-line resonator that is terminated with tunable reactive loads for reflectors and a feed line. By changing the externally applied dc magnetic field to the ferrite, beam scanning was achieved at the fixed frequency. In addition, plane of polarization can be rotated independently by changing the phase condition of the reflectors. The numerical and experimental results verified the basic concept.

In this paper, enhancement of phase-shifting nonreciprocity is proposed by using metamaterial lines with comb-shaped capacitive stubs on the normally magnetized ferrite substrate. The insertion of capacitive stubs enhances the effective permittivity, i.e., effective propagation distance in one propagation direction due to edge-guided mode propagation along the comb-shaped stub edges. The nonreciprocity of the proposed structure was numerically compared with those of other types of metamaterial lines, and transmission characteristics of the prototype circuit were measured and reproduced by the numerical simulations, verifying the enhancement.

In this paper, an enhanced bandwidth technique for a backward-wave directional coupler is proposed. The coupler is composed of a conventional microstrip line and a nonreciprocal composite right/left-handed metamaterial line using a normally magnetized ferrite substrate in order to control the dispersion characteristics. In the numerical simulation and measurement results, enhancement of the coupling bandwidth was achieved for the designed and prototype couplers by applying the dc magnetic field to the ferrite substrate.

While the leading-edge serration in owls’ wing is known to be responsible for low noise gliding and flapping flights, the findings on its aero-acoustic role have been diverse or even controversial. Here we present an experimental study of the morphological effects of leading-edge serrations on aerodynamic force production by utilizing owl-inspired, single-feather, clean and serrated wing models with different serration lengths and spacing, and by combining Particle Image Velocimetry (PIV) and force measurements. Force measurements show that an increase in the length and density of the leading-edge serrations leads to a reduction in the lift coefficient and lift-to-drag ratio at Angles of Attack (AoAs) 15°, which owl wings often reach in flight. Furthermore PIV visualization of the flow fluctuations demonstrates that the leading-edge serration-based mechanism is consistent in all serrated wing models in terms of passive control of the laminar-turbulent transition while at AoAs > 15° similar suction flow is present at leading edge resulting in a comparable aerodynamic performance to that of the clean wing. Our results indicate the robustness and usefulness of leading-edge serration-inspired devices for aero-acoustic control in biomimetic rotor designs.

A new approach to enhance the phase-shifting nonreciprocity of microstrip-line-based metamaterials with normally magnetized ferrite substrates is proposed, by using a combination of curvature of the lines and asymmetric insertion of stubs. In the analytical approach, the nonreciprocity is approximately formulated by introducing asymmetric surface admittance on the side walls at the strip edges, showing that a linear combination of two factors due to the line curvature and the difference of asymmetric admittances contributes to geometrical asymmetry of the wave-guiding structures. Numerical simulation and measurement results verify predictions from the analytical approach. It is demonstrated that a combination of larger curvature of the metamaterial lines and hybrid insertion of inductive and capacitive stubs on the inner and outer sides, respectively, provides significant enhancement of the nonreciprocity compared to the single side insertion of stubs.

An enhancement technique of phase-shifting nonreciprocity in normally magnetized ferrite metamaterial lines is proposed by applying a slow wave structure based on spoof surface plasmon. The nonreciprocity is further enhanced by inserting an appropriate value of capacitance in the corrugated metallic strip. Metamaterial lines with high dispersive characteristics and large nonreciprocity were numerically designed and demonstrated in the experiment.

In this paper, we consider cube-shaped unit cells including high-ε dielectric cubes under magnetic dipole-like resonance placed at the center and metallic mesh wires for negative permittivity to construct three-dimensional quasi-isotropic metamaterials in the microwave region. Basically, such structures suffer from their low wave impedance due to inclusion of high-ε materials. To reduce effective permittivity of the composite structures, we propose to insert additional inductance into the metallic mesh. For the insertion of lumped inductors along the wires, dispersion diagram and the Bloch-impedance are numerically estimated, and converted to effective permittivity and permeability. The numerical simulation results clearly show almost 3-D isotropic propagation characteristics in a specific frequency region and enhancement of the Bloch-impedance close to free space in the left-handed region. The lumped inductors are replaced by meander-line strip patterns for practical configurations. The metallic patterned structures also achieve the enhanced Bloch impedance that is well-matched to free space.

Nonreciprocal metamaterials using normally magnetized ferrite microstrip lines are reviewed, showing derivation of formula for the phase-shifting nonreciprocity based on the eigenmode solution in terms of the effective magnetization in ferrite and asymmetric boundary condition for the wave-guiding structures. Dispersion engineering of the nonreciprocity is also discussed for potential applications to leaky wave antennas with wide steering angles and reduced beam squint.

In this paper, we design and fabricate a unit cell block for 3-D isotropic left-handed metamaterials impedance-matched to free space which is composed of a dielectric cube and metallic mesh. The numerical simulation results show almost 3-D isotropic propagation characteristics in a specific frequency region with low reflection loss at the boundaries. Furthermore, near field profiles along the 1-D aligned array were simulated and measured verifying the backward wave mode propagation without serious field scatterings.

Dual-band and low-profile mushroom antenna with vertically-polarized and omnidirectional radiation in the horizontal direction is proposed. The mushroom antenna has multiple vias forming coaxial double ring structure at the center between a ground plane and a metallic patch. The double ring structure of vias has two different parallel resonant frequencies. It is confirmed from the numerical simulation results that the proposed antenna shows omnidirectional radiation pattern at dual-band.

Nonreciprocal metamaterials have been investigated to discover new electromagnetic phenomena and to invent state-of-THe-art functional circuits and antennas [1], [2]. By using nonreciprocal metamaterials, we can have unidirectional wavenumber vectors along the wave-guiding structures regardless of the propagation directions. Transmission-line resonators based on such noneciprocal metamaterials show unique characteristics in that the resonance frequency is independent of the resonators’ size and that the field profiles have uniform magnitude and linearly-varying phase distribution, referred to as pseudo-traveling-wave resonators [3]. In addition, phase gradient of the fields along the resonators can be arbitrarily varied by changing the nonreciprocity of the lines under the resonant condition, which is implemented to highly-efficient beam scanning leaky wave antennas [4], and to polarization-switchable circularly polarized antennas. However, most of phase-shifting nonreciprocal metamaterials have resulted in relatively small magnitude of nonreciprocity even with considerably large applied dc magnetic field with the help of strong permanent magnets or huge size of electromagnets, which limit the availability and applications to beam steering antennas for practical use. In order to make the steering beam angle wider for antenna applications or to reduce the magnitude of the dc magnetic field, enhanced nonreciprocity is essential. Recently, the phase-shifting nonreciprocity for the normally magnetized ferrite-based metamaterials was analytically formulated showing that this phenomenon is described by a product of two factors; the one corresponds to off-diagonal component in Polder permeability tensor determining gyro-magnetic characteristics. Another factor is the geometrical asymmetry which is realized by periodically and asymmetrically inserting stubs into the normally magnetized ferrite rod-embedded microstrip lines at the center [5], [6]. So far, shunt stubs periodically inserted in previous metamaterials were constructed on the non-magnetic dielectric substrates to avoid the influence of dc magnetic field on the stub performance. However, capacitive stubs constructed on the dielectric substrate suffer from the coupling between adjacent stubs and cause degradation of enhanced phase-shifting nonreciprocity. In this paper, we propose a new enhancement technique for the phase-shifting nonreciprocity in metamaterial lines loaded with comb-shaped periodic open stubs constructed on the normally magnetized ferrite substrate at one side of strip edges, as shown in Fig 1. In the configuration, the edge guided mode [7] is excited that caused zigzag propagation along each stub. This mechanism corresponds to longer distance for one propagation direction. This situation is realized by reducing the coupling between adjacent stubs. At the other side of strip edges, inductive stubs are periodically inserted to realize negative effective permittivity and to reduce the propagation distance in the opposite direction of propagation. Combination of capacitive and inductive stub insertion results in enhanced nonreciprocity. Polycrystalline Yttrium Iron Garnet was employed as the ferrite material. The configuration parameters for the prototype circuit are as follows; thicknesses of the ferrite and dielectric substrates are both 0.8 mm, dielectric constants of ferrite and dielectric substrates are 15 and 2.6, respectively. The width of the center strip is 2 mm. The length and width of capacitive stubs are 2 mm and 0.8 mm, respectively. The unit cell length is 1.9 mm. In Fig. 2, the simulated and measured phase shifting nonreciprocity Δβ are extracted from the S-parameters for five unit cells and plotted as a function of the operating frequency and externally applied dc magnetic fields. It is found from Fig. 2 that experimental results agree well with numerical simulation results. It is noted that the beam sweep of ±15 degrees in the present configuration corresponds to the nonreciprocity for the external dc magnetic field of ±26 mT only which is about a quarter compared to the typical value of 100 mT required for previous nonreciprocal metamaterials. Thus, reduction of the applied dc magnetic field required for the nonreciprocity will open up realization of tunable nonreciprocity of metamaterials and beam steering antennas for practical use.

The novel use of SiCN underneath TEOS oxide as a bonding surface in the wafer bonding of Backside-illuminated (BSI) sensor is proposed and the mechanism of void control by SiCN is clarified. In general, high-temperature processing results in generating voids between the wafer interfaces after bonding due to the release of high-pressure H 2 O contained in TEOS. In the proposed mechanism, the SiCN exposed to high-temperature H 2 O is oxidized thereby preventing the emission of high-pressure H 2 O gas. This paper analyzes the role of SiCN in this mechanism.

In this paper, a pair of tunable reactive elements for reflectors with impedances having a relation of complex conjugate is proposed based on nonreciprocal composite right/left handed transmission lines using a ferrite rod embedded substrate. These reflectors are inserted at both ends of a zeroth-order resonator. Numerical simulation results clearly show that the field profile on the zeroth-order resonator is continuously tunable by changing the applied DC magnetic field to the ferrite rods.

A pseudo-traveling-wave resonator with magnetically tunable phase gradient of field distribution is investigated, and a new type of beam-steering antenna based on the resonator is experimentally demonstrated for the first time. It is a short-ended transmission-line resonator and is composed of a nonreciprocal phase-shift composite right/left-handed transmission line using a polycrystalline yttrium-iron-garnet rod. The resonator operates as zeroth-order resonator if there is no dc magnetic field, and the radiation beam directs to broadside. By increasing an externally applied dc magnetic field normal to the substrate, the effective dc magnetization in the ferrite increases under the unsaturated regime. The phase gradient of the field distribution along the resonator is then continuously increased. As a result, the radiation beam direction changes obliquely with respect to broadside. Continuous backfire-to-endfire beam steering with more than 40° was achieved with almost constant gain of 5 dBi. In addition, numerical simulation results show considerably high radiation efficiency of 85%-95%, and the measured beam angle and gain were found almost constant within the relative bandwidth of 2%.

Simple configuration of a unit cell block including dielectric cube at the center covered with a host medium and metallic wire mesh is proposed to realize the 3-D isotropic CRLH metamaterials. The block can be flexibly stacked to construct an arbitrary shape of 3-D isotropic CRLH metamaterials with a discrete step. Influence of air gaps between adjacent blocks on the dispersion curves is also investigated. A small triangular prism is designed and fabricated to demonstrate a frequency-selective beam scanning with an angle ranging from positive to negative values. The experiment for TM mode propagation in the designed metamaterial lens clearly shows negative to positive refractive indices.

Transmission characteristics of nonreciprocal phase-shift composite right/left-handed transmission lines are experimentally investigated along with comparison to the numerical simulations. The line is composed of a microstrip line using a normally magnetized ferrite rectangular rod embedded into a dielectric substrate just below the center strip. It is experimentally verified that nonreciprocity in the amplitude of the transmission coefficients is negligibly small, whereas the nonreciprocity in the phase is still kept of the same order as previously reported.

Combination of magnetically-resonant dielectric resonators and TE cut-off waveguide structures provides unbalanced or balanced composite right/left handed transmission lines. This idea has been expanded into 1-D, 2-D, and 3-D composite structures, and can be applied to potential microwave and millimeter wave circuits and antennas in the same manner as conventional composite right/left handed transmission lines.

New configuration of anisotropic 3-D composite right/left-handed (CLRH) metamaterial structures is proposed and designed. It is composed of stacked layers using conductive mesh plates and dielectric layers including 2-D array of dielectric resonators. Balanced CLRH transmission structures are designed not only for both polarization and propagation directions in the layer plane, but also for the normal propagation. The structure is essentially anisotropic and has significant polarization dependence for the wave propagation. Still, for the wave propagation with the polarization parallel to the mesh plates, it can provide relatively small anisotropic propagation characteristics in a certain frequency region if the configuration parameters are appropriately designed. Additionally, it is numerically confirmed that the designed structure shows the left-handedness for the in-plane propagation with the normal polarization, but not right-handedness. The negative-refractive-index flat lens is experimentally demonstrated for validation.

Nonreciprocal phase-shift composite right/left handed transmission lines with small nonreciprocity in the amplitude of the transmission coefficients are proposed. The present structures are composed of a microstrip line periodically loaded with series capacitance and shunt inductance, and a ferrite rectangular rod is embedded in the dielectric substrate just below the center strip. The balanced composite right/left handed transmission line with nonreciprocal phase characteristics is designed. The numerical simulation results validate that the nonreciprocity in magnitude of the transmission coefficients is negligibly small whereas the nonreciprocity in the phase is still kept relatively large for the present configuration.

Leaky wave radiation from evanescent-mode left-handed (LH) transmission lines is investigated that are composed of a cut-off parallel plate waveguide loaded with a one-dimensional (1-D) array of the disc type dielectric resonators. The apertures are placed on side walls of the parallel plate waveguide. First of all, the dispersion diagram is numerically obtained with the complex eigenmode solutions. The simulated and measured backward wave radiation characteristics validate the backward wave propagation along the 1-D waveguides. Based on the concept, the backfire leaky wave antenna was designed and demonstrated with the 15-cell structure. The beam scanning with the operational frequency was achieved by more than 30 degrees.

A 2D negative-refractive index metamaterial is proposed and investigated, which is composed of a parallel-plate waveguide loaded with a square lattice of disc-type dielectric resonators. Collective and macroscopic behavior of the dielectric resonator lattice under the fundamental TE resonance gives negative effective permeability, whereas the parallel-plate waveguide below the cutoff for TE modes provides negative effective permittivity. Thus, the double-negative condition for the propagated waves with the appropriate polarizations can establish the left-handedness. Equivalent-circuit models are shown to give a good insight into the physical mechanism of the guided waves. Numerical simulation of the 2D dispersion diagram verifies the existence of the left-handed (LH) guided modes along with the isotropic characteristics. A triangular prism of the proposed LH structure that is sandwiched by the right-handed parallel-plate waveguides is designed and fabricated to directly observe the negative refractive index of the LH waveguide. The numerical and experimental results validate the negative refraction for the proposed structure.

In recent years, heat dissipation rates in personal computer, power devices and laser diodes have been increasing, and water-cooling technique is becoming to be used in electronic equipment cooling. When fins cannot be mounted on the heated base plate surface in the liquid channel because of manufacturing constraint, turbulence promoter is usually used in the liquid channel. We developed a heat sink with a wavy turbulence promoter facing heated base plate as a thermal enhancement technique in the liquid channel. The heat transfer coefficient of the base plate facing wavy turbulence promoter was 20000-30000W/ (m2·K). The heat transfer performance of the heat sink with a wavy turbulence promoter facing heated base plate was 3 or 4 times larger than the smooth surface channel.

A nonreciprocal left-handed transmission line is proposed and investigated, which is composed of a normally magnetized ferrite microstrip line periodically loaded with inductive stubs but without capacitive loading. The circuit configuration becomes simpler than that of a nonreciprocal left-handed transmission line with both shunt inductive and series capacitive loadings. In the proposed structure, ferrite medium is employed as the substrate not only for the nonreciprocal characteristics but also for negative effective permeability that is essential to establish the left-handedness. After calculations of dispersion curves using equivalent circuit model, scattering parameters along with field patterns are estimated numerically with the help of electromagnetic simulation, and the experiments are also carried out. It is found that the band width of the proposed left-handed transmission line is relatively narrow but the structure still has the high isolation ratio of more than 30 dB.

A lot of test pieces are usually produced in glaze studies. Data base is useful for an efficient utilization of them. Construction of two data base systems was attempted for several hundred thousand glaze test pieces accumulated during many years of ceramic studies at the National Industrial Research Institute of Nagoya. One system was for filing of glaze test pieces data as a library catalogue, while the other was opened to the public on Internet WWW. The data items of the systems were reference number, glaze name, firing temperature, firing type, color, surface conditions, Seger formula, coloring element, picture of test pieces, and so on. Construction of data items, evaluation method of color, classification of glaze, and treatment of pictures were discussed in both the systems.

A stacked image sensor with a 0.9 μm pixel size fabricated by using organic photoconductive film (OPF) was realized. It is the first trial to introduce an active material, that is, an organic semiconductor into the BEOL process. This pixel structure is fabricated by using a standard 45 nm BEOL process. However, after OPF deposition, it is essential to restrict the thermal budget and to avoid oxygen, moisture, and plasma irradiation. By controlling the above conditions, a demonstration of a stacked image sensor with OPF, which has high sensitivity, high saturation charge, and a wide incident light angle, was successfully performed.

Isotropic three-dimensional composite right/left handed (CRLH) metamaterial structure is proposed and designed. It is composed of conductive jungle gym structure and dielectric spheres with high dielectric constant. By adjusting the configuration parameters appropriately, balanced CRLH transmission structures are designed in the numerical simulation. The numerical results show that the wavenumber vector of the designed structures provides almost isotropic characteristics in a specific frequency region in the vicinity of Γ point.

A ZnO:Al target was sputtered concurrently with additional Zn or Al, by co-sputtering it with either a Zn or an Al target. The influence of the deposition of these additional atoms on the ZnO:Al film properties was investigated. When co-sputtering the Zn target, the film resistivity shows a minimum for an adequate supply of Zn. With this supply of Zn, both the carrier concentration and the Hall mobility show maxima, and the optical transmittance and absorption edge are improved. When co-sputtering with the Al target, the carrier concentration alone is increased. These results indicate that there is a considerable Zn deficiency in the ZnO:Al films prepared in pure Ar gas, and additional Zn or Al atoms during film deposition can compensate for these Zn defects, in addition to the increased donor concentration in the film.

Indium tin oxide (ITO) films were prepared by a planar magnetron sputtering system with facing ITO ceramic targets. In this case, the substrate is placed between the targets, so that film bombardment by energetic particles such as O − ions and 0 atoms can be avoided. With the addition of small partial pressure of O 2 in the atmosphere, film resistivity shows a minimum. A resistivity of 1.6×10 −4 Ω cm is attained. This value is nearly the same as the lowest value reported until now, which confirms that film preparation by the facing target system is effective in decreasing the film resistivity. Adding a greater proportion of O 2 gas in the Ar induces a decreased carrier concentration, which is due to the oxidation of Sn donor atoms and oxygen vacancies. The oxidation mechanism is discussed.

Time-resolved compression of a laser-driven solid deuterated plastic sphere with a cone was measured with flash Kα x-ray radiography. A spherically converging shockwave launched by nanosecond GEKKO XII beams was used for compression while a flash of 4.51 keV Ti Kα x-ray backlighter was produced by a high-intensity, picosecond laser LFEX (Laser for Fast ignition EXperiment) near peak compression for radiography. Areal densities of the compressed core were inferred from two-dimensional backlit x-ray images recorded with a narrow-band spherical crystal imager. The maximum areal density in the experiment was estimated to be 87 ± 26 mg/cm2. The temporal evolution of the experimental and simulated areal densities with a 2-D radiation-hydrodynamics code is in good agreement.

Transparent conductive ZnO:Al films were prepared in Ar gas by a planar magnetron sputtering system with facing targets, where strong internal magnets were contained in target holders to confine the plasma between the targets. A film resistivity of 4 × 10 −4 Ω cm was attained at a substrate temperature of 200 dgC. However, the film resistivity increased with increasing substrate temperature, due to a decrease of the carrier concentration. The reason for this phenomenon was the decrease of Zn donors in the film as native donors or an increase of Zn defects. When excess Zn atoms were supplied during film growth, a low resistivity of 2 × 10 −4 Ω cm was obtained even at a substrate temperature of 250 °C.

High performance 32nm-node interconnect with ELK (Extremely Low-k, k=3D2.4) has been demonstrated. To suppress process damage and enlarge the via-line space with a wide lithography process margin, robust ELK film with a metal hard mask (MHM) self-aligned via process has been developed. It has accomplished both ultimate low capacitance wirings and high TDDB reliability between Cu lines with vias. In addition, a novel technique of interface engineering between ELK and a liner layer has been developed to strengthen the tolerance against chip packaging. This has achieved highly reliable chip packaging. This complete process has a high manufacturability and it therefore offers a promising technology for the 32-nm node and beyond.

We have improved ELK film so that it is suitable for the processes used in fabricating Cu interconnects without using a dielectric protection layer for CMP, the so called “direct CMP process”. The depth profile of the pore size in the film was successfully controlled to prevent water absorption during the CMP process with a limited k-value increase in the film. The line-to-line dielectric breakdown voltage and the time dependent dielectric breakdown lifetime at the 45 nm spacing for the advanced ELK interconnects without the DPL were significantly improved.

New configuration of anisotropic 3-D composite right/left handed metamaterial structures is proposed and designed. It is composed of stacked layers using conducting mesh plates and dielectric layers including 2-D array of dielectric resonators. Balanced composite right /left handed transmission structures are designed not only for the propagation direction parallel to the layers, but also for the normal direction. The structure is essentially anisotropic and has polarization dependence for the wave propagation. Still, for the wave propagation with the polarization parallel to the mesh plates, it can provide relatively small anisotropic propagation characteristics in some frequency region by appropriately designing the configuration parameters. The negative-refractive-index flat lens is demonstrated for the validation.

In order to control the characteristics of porogen-based porous SiOC film (k ≪ 2.5), we investigated its dependence on the wavelengths of ultraviolet (UV) light by using methods of FT-IR, TDS and nano-indentation. As a result, it was found that specific wavelengths of UV light strongly was effective to porous SiOC film production : porogen desorption, mechanical strength improvement, and reduction of the film damage. Vacuum ultraviolet (VUV) irradiation is necessary for porogen desorption. However, after porogen was removed from SiOC film, the energy of VUV irradiation was too high for porous SiOC film and this caused film damage. The energy of deep ultraviolet (DUV) irradiation was sufficient to improve mechanical strength. We propose that UV curing process should be a multi-step process consisting of VUV and DUV irradiation (Figure 1). The first step removes porogen using VUV irradiation. The second step forms robust porous SiOC film using DUV irradiation. A multi-step curing process was used to control the characteristics of porogen-based porous SiOC film.

In order to reduce the effective dielectric constant (keff) for the 32 nm technology node and beyond, Direct-CMP of a porous low-k film without a protective cap layer is required. However, the degradation of breakdown electric field (Ebd) has been one of critical issues. This study clarified that the Ebd degradation was caused by the pit defects on the surface of porous low-k film during Direct-CMP. In order to suppress the pit defects, we evaluated dependency of micro-pores density of CMP pads. As a result, we demonstrated that CMP pads with low-density micro-pores drastically reduced them and improved the Ebd degradation. In this paper, the mechanism for their reduction is also discussed.

We present the experimental results on strong optical-microwave interaction in yttrium iron garnet (YIG) single-crystal. Optical interactions with different microwave modes namely, quasi-transverse electromagnetic (quasi-TEM), edge-guide and magnetostatic surface wave (MSSW) modes are presented. Wide-band optical response of the magnetic wall resonance is observed at 1 GHz. Nonreciprocal characteristics of an edge-guide mode ferrite isolator at microwave frequency is observed in the optical output. The standing wave pattern of MSSW is also observed by using an optical probe. The phenomenon is discussed with reflection of optical plane wave by Bloch walls.

In this paper, stacked structures composed of mesh plates and dielectric layers including 2-D array of dielectric discs are proposed as a new type of volumetric composite right/left-handed metamaterial structure for TE-polarized waves. No band gap condition between right and left-handed bands is designed in order to broaden the left-handed bandwidth by adjusting the aperture size of the mesh. Based on this layered metamaterial structure, a flat focusing lens which operates in free space is designed and fabricated. For a source launched from a small loop antenna, beam focusing through the fabricated finite-cell-layered lens is experimentally confirmed by measuring the field profiles.

A new configuration of composite right/left handed (CRLH) metamaterial structure is proposed, which comprises of TE-resonant dielectric resonators and metallic parallel mesh plates. The balanced CRLH transmission lines are designed by adjusting the optimal distance between the mesh plates for a given size of the mesh windows. To confirm the fundamental operation, the transmission and far field radiation characteristics are simulated and measured for the one-dimensional structure. The numerical results show that the increase in the thickness of metallic mesh plates dramatically reduces the radiation efficiency. Nevertheless, the numerical simulation and measurement validate the continuous change in the phase flow along the waveguide from backward to forward directions with the operational frequency.

We present a left-handed material (LHM) at optical wavelength. Our structure consists of polystyrene spheres on layers of metals. Measurement of LHM is discussed, suggesting that our structure has a negative refractive index near 470nm.

Dual damascene Cu interconnects with Keff below 2.0 have been demonstrated for the first time. Air gaps between Cu lines were formed with a low K SiOC film in a carefully designed manner. CoWP cap layers were introduced to protect the Cu lines and to eliminate a dielectric liner layer. In addition, AGE (Air Gap Exclusion) was applied to solve crucial problems related to the air gaps. Keff of 1.9 was obtained at 65 nm design rule, which surpassed by far ITRS target (2.5~2.8) for hp 45. It was also confirmed that leakage current between lines was suppressed by the formation of the air gaps.

Leaky wave radiation from a one- dimensional left-handed transmission line is investigated that is composed of a cut-off parallel plate waveguide loaded with dielectric resonators (DR). The left-handedness is established by the combination of negative effective permittivity due to the cut-off TE parallel plate waveguide mode and negative effective permeability originating from the macroscopic behavior of DRs under the fundamental TE resonance. The DRs are placed near an aperture on the side wall of the parallel plates. The numerical simulation and the measurement of the radiation patterns verify the backward wave propagation along the proposed waveguide, and the promising characteristics for applications to leaky wave antennas.

A two-dimensional (2-D) negative-refractive-index metamaterial is proposed, which is composed of a parallel-plate waveguide and a square lattice of dielectric resonators (DR) inserted in it. The collective and macroscopic behavior of the DR lattice under TE resonance gives negative effective permeability whereas the parallel-plate waveguide below the cut-off for fundamental TE modes shows negative effective permittivity, which leads to the left-handedness. The 2-D triangular prism of the proposed left-handed waveguide that is sandwiched by right-handed parallel-plate waveguides provides the numerical and experimental demonstrations of the negative refraction for the propagated waves.

A new technology for manufacturing low Keff (