ECE Assistant Professor Rinaldi Awarded Two Patents
ECE Assistant Professor Matteo Rinaldi was awarded a patent for the “Cross-Sectional Lamé-Mode Resonator (CLMR)” technology.
This patent describes the invention of a new class of piezoelectric micro-acoustic resonators based on the piezoelectric transduction of a Lamé mode in the cross-section of a piezoelectric plate. These new devices are dubbed Cross-Sectional-Lamé-Mode Resonators (CLMRs). Differently from any resonator technology demonstrated to date, CLMRs rely on a coherent combination of multiple piezoelectric coefficients of a piezoelectric material to transduce a 2-dimensional (2D) mechanical mode of vibration, which is characterized by longitudinal vibrations along both the width and the thickness of the plate. This feature enables the implementation of CLMRs with high values of electromechanical coupling coefficient (i.e. kt2>7% in Aluminum Nitride). In addition, due to dependence of such 2D mode on the lateral dimensions of the plate, CLMRs operating at significantly different frequencies can be lithographically defined on the same substrate without requiring additional fabrication steps. The capability of achieving high Figure of Merit (FOM, defined as the product between the resonator electromechanical coupling coefficient, kt2, and quality factor, Q), comparable to the ones of commercially available Aluminum Nitride (AlN) thin film bulk acoustic resonators (FBARs), and multiple operating frequencies on the same chip without additional fabrication costs (lithographic tunability of the resonance frequency), makes this technology one of the best candidate for the implementation of monolithic integrated contiguous and not-contiguous filters for platforms adopting carrier-aggregation (CA). An AlN CLMR prototype operating around 920 MHz has been demonstrated by Rinaldi’s group showing kt2 and FOM in excess of 6.2% and 108, respectively, which are the highest ever demonstrated in AlN resonators operating in the same frequency range.
A resonator including a piezoelectric plate and an interdigital electrode is provided. A ratio between a thickness of the plate and a pitch of the interdigital electrode may be from about 0.5 to about 1.5. A radiation detector including a resonator and an absorber layer capable of absorbing at least one of infrared and terahertz radiation is provided. A resonator including a piezoelectric plate and a two-dimensional electrically conductive material is provided.