Infineon Technologies Ag

Nokia Corporation

Avago Technologies Wireless IP (singapore) Pte. Ltd.

Lüder Elbrecht

Robert Aigner

Stephan Marksteiner

Winfried Nessler

Pasi Tikka

Juha Ellä

Hans-Jörg Timme

Katri Helena Pohjonen

In a method of producing an electrode for a resonator in thin-film technology, the electrode of the resonator is embedded in an insulating layer such that a surface of the electrode is exposed, and that a surface defined by the electrode and the insulating layer is substantially planar.

Method of producing a topology-optimized electrode for a resonator in thin-film technology

A filter device and a method for fabricating filter devices can package filters, especially acoustic wave filters, by bonding a carrier (substrate) wafer carrying manufactured filters to another wafer referred to as a capping wafer. A capping wafer/substrate eliminates the need for a conventional package to protect the sensitive filters, which reduces both product size and product costs significantly. Even though additional packaging is possible (i.e. in plastic molded packages, or in glob-top packages), it is not required for the reliability of the filters.

Filter device and method for fabricating filter devices

The invention relates to bulk acoustic wave filters including at least two bulk acoustic wave resonators. Each of these resonators includes at least one first electrode, a piezoelectric layer, and a second electrode. At least two of the bulk acoustic wave resonators have effective resonator surfaces which differ in their surface form and/or surface content. The inventive design of the bulk acoustic wave resonators enables optimal suppression of interference modes without influencing the impedance level of the filter.

Bulk acoustic wave filter utilizing resonators with different aspect ratios

Growing community of inventors

Munich, Germany

Lüder Elbrecht