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In this paper, we introduce a novel on-chip capacitive sensor design and a motion estimation method for measuring multi-axis out-of-plane tilting motion of a micro-stage that is used for in situ calibration of an integrated MEMS gyroscope. On-chip sensing and motion estimation is critical for this application, since precision in measuring high frequency tilting motion of the micro-stage determines how accurately an on-stage MEMS gyroscope can be calibrated in the field with respect to this motion. To obtain decoupled sensing signals from multi-axis out-of-plane tilting motion, a capacitive sensing layout with high off-axis signal rejection capability is introduced. With the proposed design specifications and range of tilting motion, a dual axis capacitive sensor model is developed, and simulation results show that the sensor is able to reject more than 99.90% of the off-axis signal. The sensor also permits detection of perturbations to stage geometry due to ambient temperature variation through the effects of nonlinear behavior on signal timing. To measure tilting motion with the obtained sensing signal, a motion estimator with extended Kalman Filter (EKF) is also developed. With assistance of a laser Doppler vibrometer (LDV), experiments are performed to identify the parameters of the motion estimator and validate its performance. The experimental results demonstrate a 286 ppm error in scale factor calibration of a commercial MEMS gyroscope by the micro-stage with moderate temperature variation.

Low-dielectric-constant SiOC(–H) thin films were deposited on p -type Si(100) substrates using plasma enhanced chemical vapor deposition (PECVD) from vinyltrimethylsilane (VTMS; CH 2 = CHSi(CH 3 ) 3 ) and oxygen gas as precursors. To improve the structural, mechanical and electrical characteristics, SiOC(–H) films deposited using PECVD were post-treated by ultraviolet (UV) irradiation for various time intervals. Carbon content of the SiOC(–H) films increased before 240 s of UV irradiation time. But carbon-bonded functional groups of the SiOC(–H) film, in case of 480 s UV irradiation time, is replaced with Si–O bond. Because the Si–CH n bond groups are broken due to UV irradiation, Therefore, the films are formed with Si–O bond rich in the Si–O–C(–H) structure. The lowest relative dielectric constant, leakage current density, the elastic modulus and the hardness of SiOC(–H) with 240 s of UV irradiation time were about 2.07, 2.1 × 10 −7 A/cm 2 , 43 GPa, and 3.68 GPa, respectively. The results indicate that the SiOC(–H) films exposed by UV irradiation improve the structural, mechanical, and electrical characteristics.

Low-dielectric constant SiOC( H) films were deposited on p -type Si(100) substrates by plasma-enhanced chemical-vapor deposition (PECVD) using dimethyldimethoxy silane (DMDMS, C 4 H 12 O 2 Si) and oxygen gas as precursors. To improve the physicochemical properties of the SiOC( H) films, the deposited SiOC( H) films were exposed to ultraviolet (UV) irradiation in a vacuum. The bonding structure of the SiOC( H) films was investigated by Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The electrical characterization of SiOC( H) films were carried out through I–V measurements using the comb-like patterns of the TiN/Al/Ti/SiOC( H)/TiN/Al/Ti metal–insulator–metal (MIM) structure. Excessive UV treatment adversely affected the SiOC( H) film, which resulted in an increased dielectric constant. Our results provide insight into the UV irradiation of low- k SiOC( H) films.

Carbon doped silicon oxide (SiOCH) thin films deposited using plasma-enhanced chemical vapor deposition (PECVD) are commonly used in multilevel interconnect applications. To enhance the electrical performance, the deposited SiOC(–H) films were annealed in a vacuum at various temperatures ranging from 250 to 450 °C. A Cu electrode was then deposited using thermal evaporation. The drift rate of Cu + ions in the SiOC(–H) films with the Cu/SiOC(–H)/ p -Si(100)/Al metal–insulator–semiconductor (MIS) structures after annealing was evaluated by C–V measurements with a flatband shift caused by bias-temperature stress (BTS). The samples were stressed at different temperatures of 150 to 275 °C and electric fields up to 1.5 MV/cm to examine the penetration of Cu + ions into the SiOC(–H) films. The Cu + ion drift diffusion behavior was observed by high-resolution transmission electron microscopy and depth profile analysis of the Auger electron spectra. The drift diffusion experiments suggested that the Cu + ion drift rate in the of SiOC(–H) films increased with increasing annealing temperature. A thermal stress and BTS were used to evaluate the impact of Cu penetration on the dielectric properties of the SiOC(–H) films.

Low dielectric constant SiOC(–H) films were deposited on p-type Si(100) substrates by plasma-enhanced chemical vapor deposition (PECVD) using dimethyldimethoxysilane (DMDMOS, C4H12O2Si) and oxygen gas as precursors. We studied the detailed electrical characterization of SiOC(–H)/p-Si(100) interfaces using different experimental parameters for using the multilevel interconnections in ultra large-scale integrated circuits (ULSI). To improve the SiOC(–H)/p-Si(100) interface, the wafer was cleaned using the RCA process and rinsed with deionized water. The deposited SiOC(–H) films were annealed at different temperatures ranging from 250 to 450 °C in a vacuum. The interface properties of the SiOC(–H)/p-Si(100) with Cu/SiOC(–H)/p-Si(100)/Al metal–insulator–semiconductor (MIS) structures were investigated by capacitance–voltage (C–V) measurement with a flat band shift by electric field stress. Trapped charge, fixed oxide charge, and the interface trap density of SiOC(–H) films were related to the dielectric breakdown and leakage current density at the SiOC(–H)/p-Si(100) interface. From these analyses, detailed electrical properties defining the interface states of the MIS structures were reported.

A simple method has been developed to suppress the DC term in in-line digital holographic microscope images. The technique is based on the use of the average intensity of a variable number of pixels rather than a fixed number of pixels. The DC-suppression ratio is similar to that associated with the averaging method proposed by Kreis and Juptner, while the image quality resulting from the new method is higher. This method can potentially yield significant improvements in the quality of reconstructed images.

Research and developments of a xenon weakly interactive massive particle (WIMP) searching detector have been done for a couple of decades. The weakness of signal amplitudes gives some difficulties to increase the detection efficiency. We brief a possible primary signal amplification method with an internal photo cathode and the secondary amplification method with electroluminescence technique. Using those methods, we achieved 1.8 × 102 ± 40 times amplification ratio for a primary scintillation and 4.3 × 10 ± 5 times amplification ratio for a secondary one. It will maximize the efficiency of a xenon detector to search for the super-symmetric dark matter, WIMP. Also we describe the response characteristics of a xenon detector that is exposed by cosmic ray on the ground level. We describe the possible detection region for a WIMP signal in the primary–secondary plot. We will show a possible WIMP signal detected by xenon detector. Here we also remind the detailed working mechanism of a xenon detector searching for the WIMP dark matter.