A cost effective low temperature co‐fired ceramics antenna with wide beamwidth and high gain at 77 GHz is presented. This antenna consists of an aperture coupled dielectric resonator antenna which provides high gain and wide beamwidth. The vias surrounding the dielectric resonator act as a metallic fence, and prevent signal leakage. The top surface of this antenna is covered with dielectric layer, and no metal pattern was exposed to the air. Fabrication cost can be reduced by eliminating the expensive gold plating process due to this top passivation layer. The simulated results of the proposed antenna show a wide beamwidth of 86° and a peak antenna gain at 76.5 GHz of 7.5 dBi.

High-beam-current microcolumns with large apertures were fabricated using a new process to improve etch uniformity and the quality of apertures of microlens. The properties of microcolumns were examined by varying the beam energy from 200 to 800 eV. The probe beam current of the sample was measured to be up to ∼5 nA at a total beam current of ∼1 µA and a working distance of ∼1 mm. The microcolumns readily distinguished carbon nanotube (CNT) sample wires with a diameter of 100 nm. The fabrication processes and the properties of high-beam-current microcolumns are presented.

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A new antenna structure with broadband and high gain at the millimetre wave bands is presented. This antenna consists of a conventional patch fabricated on a thick low-temperature cofired ceramic (LTCC) substrate. By introducing an inner ground plane surrounding the main patch, the propagation of the surface wave is prevented, and antenna gain is increased. Furthermore, the bandwidth of this antenna becomes wider due to the coupling between the main patch resonator and the newly introduced dielectric resonator. The simulated results of the proposed antenna show a bandwidth and peak antenna gain at 60 GHz of 12 GHz and 9.4 dBi, respectively.