Showing papers by "Roozbeh Tabrizian published in 2010"

Temperature-Stable High-Q AlN-on-Silicon Resonators with Embedded Array of Oxide Pillars

Abstract: This paper reports on a new temperature compensation technique for high-Q AlN-onSilicon bulk acoustic wave resonators. A uniform array of silicon dioxide (SiO2) pillars are formed in the silicon body of the resonator to generate a composite resonator with a near-zero temperature coefficient of frequency (TCF). At a resonance frequency of 24MHz, a total frequency drift of 90 ppm over the temperature range of −20 °C to 100 °C was measured while Q exceeded 10,000 at all temperatures. This compensation technique is applicable to bulk acoustic resonators with thick silicon substrate that demonstrate high Q as well as good power handling and linearity. Copyright Notice

Methods of Forming Micromechanical Resonators Having High Density Trench Arrays Therein that Provide Passive Temperature Compensation

Abstract: A method of forming a micromechanical resonator includes forming a resonator body anchored to a substrate by at least a first anchor. This resonator body may include a semiconductor or other first material having a negative temperature coefficient of elasticity (TCE). A two-dimensional array of spaced-apart trenches are provided in the resonator body. These trenches may be filled with an electrically insulating or other second material having a positive TCE. The array of trenches may extend uniformly across the resonator body, including regions in the body that have relatively high and low mechanical stress during resonance. This two-dimensional array (or network) of trenches can be modeled as a network of mass-spring systems with springs in parallel and/or in series with respect to a direction of a traveling acoustic wave within the resonator body during resonance.