Our previous research work indicated that highly boron doped polysilicon nanofilms (≤100 nm in thickness) have higher gauge factor (the maximum is ∼34 for 80 nm-thick films) and better temperature stability than common polysilicon films (≥ 200nm in thickness) at the same doping levels. Therefore, in order to further analyze the influence of deposition temperature on the film structure and piezo...

We report an optical phased array (OPA) for two-dimensional free-space beam steering. The array is composed of tunable MEMS all-pass filters (APFs) based on polysilicon high contrast grating (HCG) mirrors. The cavity length of each APF is voltage controlled via an electrostatically-actuated HCG top mirror and a fixed DBR bottom mirror. The HCG mirrors are composed of only a single layer of poly...

Based on PVDF (piezoelectric sensing techniques), this paper attempts to study the propagation law of shock waves in brittle materials during the process of three-wavelength laser irradiation of polysilicon, and discusses the formation mechanism of thermal shock failure. The experimental results show that the vapor pressure effect and the plasma pressure effect in the process of pulsed laser ir...

Silicon films of submicrometer thickness play a central role in many advanced technologies for computation and energy conversion. Numerous thermal conductivity data for silicon films are available in the literature, but they are mainly for the lateral, or in-plane, direction for both polycrystalline and single crystalline films. Here, we use time-domain thermoreflectance (TDTR), transmission el...

The processes for the neuronal microneedle are performed with only one ordinary double-polished (100) silicon wafer. The buried microchannel in the neuronal microneedle is fabricated using the processes of anisotropic dry etching, sidewall passivation, isotropic dry etching, and trench-refilling with a LPCVD polysilicon film. Because the microchannel fabrication process in this thesis uses the ...

Wear and fatigue are important factors in determining the reliability of microelectromechanical systems (MEMS). While the reliability of MEMS has received extensive attention, the physical mechanisms responsible for these failure modes have yet to be conclusively determined. In our work, we use a combination of on-chip testing methodologies and electron microscopy observations to investigate th...

A MEMS-first fabrication process for integrating CMOS circuits with polysilicon micromechanical structures is described in detail. The overall process uses 18 masks (22 lithography steps) to merge a p-well LOCOS CMOS process that has one metal and two polysilicon layers with a surface micromachining process that has three layers of polysilicon. The microstructures are formed within recesses on ...

The current condition and outlooks of the world semiconductor polycrystalline silicon (poly-Si) markets have been analyzed. A long period low PS prices which hindered growth investments into industry has now changed for price recovery to an investment attractive level. Demand offer balance until 2024 term analyzed, main currently used processes reviewed. poly-Si market proficiency is expected r...