11,679 research outputs found
Fracture strain of LPCVD polysilicon
A polysilicon bridge-slider structure in which one end of the bridge is fixed and the other is connected to a plate sliding in two flanged guideways, is designed and fabricated to study the strain at fracture of LPCVD polysilicon. In the experiments, a mechanical probe is used to push against the plate end, compressing and forcing the bridge to buckle until it breaks. The distance that the plate needs to be pushed to break the bridge is recorded. Nonlinear beam theory is then used to interpret the results of these axially-loaded-bridge experiments. The measured average fracture strain of as-deposited LPCVD polysilicon is 1.72%. High-temperature annealing of the bridge-sliders at 1000°C for 1 h decreases the average fracture strain to 0.93%
Path ideals of rooted trees and their graded Betti numbers
Let be a rooted tree and let be a positive integer. We study
algebraic invariants and properties of the path ideal generated by monomial
corresponding to paths of length in . In particular, we give a
recursive formula to compute the graded Betti numbers, a general bound for the
regularity, an explicit computation of the linear strand, and we characterize
when this path ideal has a linear resolution.Comment: 18 page
Topics in electrodynamics of moving media Final report, 1 May 1965 - 1 May 1966
Electrodynamics of moving medi
The dyadic green's function for an infinite moving medium
Derivation of dyadic Green function for electromagnetic field in moving medium using Minkowski theory and method of Fourier analysi
Silicon micromachined waveguides for millimeter-wave and submillimeter-wave frequencies
The development of micromachining techniques to create silicon-based waveguide circuits, which can operate up to high submillimeter-wave frequencies, is reported. As a first step, a WR-10 waveguide has been fabricated from (110) silicon wafers. Insertion loss measurements on a gold-plated silicon waveguide show performance comparable to that of standard metal waveguides. It is suggested that active devices and planar circuits can be integrated with the waveguides, solving the traditional mounting problems
Corrosion Behavior of Parylene-Metal-Parylene Thin Films in Saline
In this paper, we study the corrosion behavior of parylene-metal-parylene thin films using accelerated-lifetime soak tests. The samples under test are thin film resistors with a 200 nm layer of Au sandwiched by parylene-C on both sides, fabricated with parylene-metal skin technology. The samples are tested in hot saline both passively and actively, and different failure modes are observed using optical and electron-beam metrologies. Bubbles and delamination are first seen in the samples after 2 days of soaking under passive conditions, and followed by metal corrosion. While under active conditions, either bubbles or parylene breakdowns are observed depending on the thickness of parylene packaging. These results contribute to a better understanding of the failure mechanisms of parylene packaging in body fluids
Electrolysis-based diaphragm actuators
This work presents a new electrolysis-based microelectromechanical systems (MEMS) diaphragm actuator. Electrolysis is a technique for converting electrical energy to pneumatic energy. Theoretically electrolysis can achieve a strain of 136 000% and is capable of generating a pressure above 200 MPa. Electrolysis actuators require modest electrical power and produce minimal heat. Due to the large volume expansion obtained via electrolysis, small actuators can create a large force. Up to 100 µm of movement was achieved by a 3 mm diaphragm. The actuator operates at room temperature and has a latching and reversing capability
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