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• A low-pass filter has been designed using periodic self-similar coplanar waveguide. • The filter is used in large integrated or hybrid circuits without require wire bonding. • The paper gives the MEMS surface fabrication processing of the filter. • The MEMS switch has relatively lower driven voltag with 26 V. This paper presents a low-pass filter based on microelectromechanical system using periodic self-similar coplanar waveguide. The device is fabricated on 525-μm high-resistivity silicon substrate using surface micromachining process which partial compatible process with IC. The tunable resonant frequency is achieved using micro-electromechanical contact capacitive switches. The total area of the filter is about 6 mm2 including bias lines and pads. The parameters of the filter has been analyzed by applying the Ansoft-HFSS. When switch is on original state, the measured results of the filter show that the 3-dB cutoff frequency is 16.15 GHz with the average insertion loss of 0.95 dB. The 3 dB cut-off frequency of the reconfigurable filters is 22.85 GHz with the average insertion loss of 2.33 dB. A relatively lower driven voltage is around 26 V. [ABSTRACT FROM AUTHOR]

GaN-based LEDs with different thickness of n-GaN have been grown on 4-in. Si(1 1 1) substrate by metal–organic chemical vapor deposition. Quality of GaN epilayer has been evaluated by X-ray diffraction (XRD). Strain information in the structure has been directly investigated by means of micro-Raman scattering. It can be concluded that the compressive strain has varied to a tensile one with increasing n-GaN thickness from 0.5 to 2.0 μm. As a result, in a sample with a 2 μm n-GaN thickness, the tensile stress of GaN epilayer was calculated to be 0.44 GPa. Moreover, the strain states of GaN epilayer have been revealed from the variations of its a - and c -lattice constants, which have been calculated using XRD results. In addition, emission peak shift of GaN epilayer has been confirmed by cathodoluminescence measurement, and light output power of LEDs has also been measured. Nevertheless, some correlations in this study would inspire researcher to design much more reasonable GaN-LEDs structures in future. [ABSTRACT FROM AUTHOR]