DCS Tx filters using AlN resonators with iridium electrodes.
In this paper we present the design, fabrication technology, and characterization of BAW filters for the Digital Cellular System (DCS) Tx-band at 1.75 GHz. The filters are fabricated with AlN-based solidly mounted resonators (SMR) using iridium electrodes, in an attempt to increase the effective electromechanical coupling factor of the BAW devices and achieve the bandwidth requirements of DCS filters. The design and optimization of the filters is performed with a simulation tool that uses a circuit model to compute the filter frequency response. Tx filters with balanced inputs and outputs and different topologies are designed and fabricated. The experimental filter response is compared with the simulations to determine the suitability of each design. DCS bandwidth requirements are fulfilled by using Ir/AlN/Ir stacks.
Clement
Marta
M
Grupo de Microsistemas y Materiales Electrónicos, Universidad Politécnica de Madrid, Madrid, Spain. mclement@etsit.upm.es
Iborra
Enrique
E
Olivares
Jimena
J
Rimmer
Nick
N
Giraud
Sylvain
S
Bila
Stéphane
S
Reinhardt
Alexandre
A