Transcript Slide 1
Miniaturization of Microfabricated Intermediate Frequency Filters Advisor Operation: Signal Filter Jaymes Hanna Jamol Pender Specifications: IF Filters Characteristic Dr. Gianluca Piazza Electrical and Systems Engineering University of Pennsylvania Center Frequency Wireless System: Cellphone Abstract 3dB Bandwidth Insertion Loss Power Handling Rejection Shape Factor (@ ±30dB) Load RF Filter/Switch Module Micro-Electro-Mechanical Systems MEMS use electrical and mechanical properties of microstructures for the realization of compact and low power sensors and actuators. MEMS devices are now pervasive in many major industries, including display electronics and wireless devices. The MEMS resonators for this project are made out of aluminum nitride (AlN), which has optimal mechanical and electrical properties for filtering and frequency-setting applications. AlN contour-mode filters offer reduced power consumption and increased space efficiency and the ability to span several frequencies on the same silicon chip. These devices can provide selective filter bands over a wider range of frequencies (MHz—GHz) than is currently possible on a single integrated chip. We report the techniques used for designing the IF filter starting from piezoelectric contourmode MEMS resonators. The devices have been designed using software such as MatLab and Cadence. A custom process was employed for the microfabrication of these structures. PA Module Transceiver Module Baseband Module Unit 150 / 300 / 450 1.0 2.5 ≤ 10 > 30 3 MHz 50 Ohms % dB dBm dB - ºC ppm/ºC MEMS Mechanically Deforming Structures Resonator Designs: AlN Layer Expansion Pt Electrodes High-Order Bar Resonator Contraction Filter Design: Single-Tether Ring Resonator f1 f S Case A Laboratory for Research on the Structure of Matter, Edison Building 3231 Walnut Street, Phila., PA 19104 Dual-Tether Ring Resonator Simulations, Fabrication & Results: IL = 1.00 dB Rejection = 65.59 dB BW = 5.80 MHz = 1.93 % Cc Case A 9:30 – 10:00, 1:30 – 2:30 Thursday, April 19, 2007 — 3-Stage: f1 f1 Input Demo Day Times and Place IL = 0.67 dB Rejection = 41.72 dB BW = 5.50 MHz = 1.83 % Value Temperature Range -40 – +85 Temperature -25 Response Coeff. i1 — 2-Stage: Specification Fabrication: i2 Output f2 f2 Input i1 Cc i2 Case B CAD Layouts: Output 150 MHz : 27(W) x 680(L) μm 300 MHz : 13.5(W) x 680(L)μm 450 MHz : 9.0(W) x 680(L) μm High-Order Bar CM f 2 f 1 1 Cc W Case B L = 680 / 4 =170 Current Best Results: High-Order Bar Single-Tether Ring W Expected Results of 2, 3-Stage Filter