Heavily-Doped Dual-Mode Distributed Lamé Resonator (DLR) for Temperature-Compensated Mems Oscillators

This paper reports on the implementation and characterization of a heavily-doped dual-mode distributed Lamé resonator (DLR) with a large frequency spacing between its two resonant modes at 49 MHz and 830 kHz, exhibiting a beat frequency with very high TCf ”23,350 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{ppm}^{\circ}\mathrm{C}$</tex>, the highest recorded beat frequency TCf to-date. The distributed Lamé (DL) mode of the resonator exhibits the highest reported frequency turnover point <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(250^\circ\mathrm{C})$</tex> of any MEMS resonator. Chip-scale ovenization of a wafer-level-packaged DLR is demonstrated at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$250^{\circ}\mathrm{C}$</tex>, showing sub-part-per-billion (ppb) stability for the oscillator.