| Electron cyclotron resonance (ECR) and inductively coupled plasma (ICP) sources have been used to generate a Cl2 plasma. Trenches > 100 μm deep have been etched in Si. High microwave power was used to achieve Si etch rates of 1.09 μm/min in a Cl2 plasma and 1.89 μm/min in a Cl2/SF6 plasma, while maintaining the vertical profile and smooth surface. Features with aspect ratios >30 have been fabricated.; An electron beam lithography system was used to pattern features as small as 0.1 μm. An etch has been developed to fabricate released 2 μm wide cantilevered single crystal Si beams as long as 500 μm with 0.1 μm gaps between them. Comb driven clamped-clamped beam resonators that are 3.1 μm thick with 0.2 μm gaps between comb fingers have been fabricated and tested.; A frontside-release etch-diffusion process has been developed to create released, single crystalline Si microstructures. Resonant microstructures 10 to 55 μm thick have been fabricated using this process. For typical clamped-clamped beam resonators that were 24 μm thick, 5 μm wide, and 400 μm long, with 2 μm comb gaps, a resonant frequency of 90.6 kHz and a quality factor of 362 were measured in air.; A simple process has been developed which combines thick single crystal Si micromechanical devices with a conventional bipolar complementary metal oxide semiconductor (BiCMOS) integrated circuit process. Clamped-clamped beam Si resonators that were 500 μm long, 5 μm wide, and 11 μm thick have been fabricated and tested with a CMOS transimpedance amplifier on the same chip. A typical resonator had a resonant frequency of 28.9 kHz and a maximum amplitude of vibration at resonance of 4.6 μm in air.; An accelerometer has been designed, simulated, fabricated, and tested using the technology described. As the gaps are scaled down to 0.1 μm the designed detectable acceleration is 4.40 μg/Hz1/2, limited by thermo-mechanical noise. The fabricated accelerometer with 1 μm beams and 0.2 μm comb gaps had a spring constant of 0.127 N/m, close to the simulated value of 0.146 N/m and a sensitivity of 6.3 fF/g, close to the calculated sensitivity of 7.0 fF/g,... |
