Surface Dynamics Research Team

Surfaces Dynamics – this means to us research on high frequency ultrasound phenomena going along with Surface Acoustic Waves (SAW) as well as with Bulk Acoustic Waves (BAW). All this research is combined with the investigation of polar dielectric materials in order to gain a thorough understanding for applications in modern microacoustics, for implementation of new device principles and for material innovations finally resulting in a higher device performance. Our work is dedicated to fundamentals as well as to applied research. Besides collaboration with scientific groups, our specialty is a very intense co-operation with industrial partners. Hereby, the current field of interest comprises concepts, materials and applications of surface acoustic waves. Investigation of general phenomena in crystal acoustics is an important base for us to develop new device concepts including advanced design principles and improved methods for physical modelling of SAW-based frequency filters. This strongly application oriented research is usually executed in direct collaboration with industry. Another essential is detailed knowledge of acoustic properties, especially for the application of new promising materials. For this reason, we precisely characterize solid state materials like single crystals, ceramics and layered structures with respect to their elastic, dielectric, piezoelectric, ferroelectric and ferroelastic properties. Furthermore, we are active in the emerging trend of utilization of microacoustic elements as sensors and actuators. Examples are SAW- and BAW-based sensors for characterization of fluids as well as microfluidic mixers and atomizers.

The research team Surface Dynamics is a core part of SAWLab Saxony - the scientific network for acoustoelectronics !

Research topics

  • General microacoustic phenomena
  • New design principles for SAW devices
  • High-precision material characterization
  • Microacoustic sensors and actuators

 

 

Group Leader: Dr. Hagen Schmidt

Phone: +49 351 4659 278

Email

The Surface Dynamics Group possesses or has easy access to all equipment needed for the work on modern SAW systems . This includes a variety of unique and state-of-the-art tools and instruments for advanced simulation and extensive evaluation of thin films and bulk samples, as well as for the precise characterization of microacoustic devices under different ambient conditions:

  • Proprietary software tools for
    - Searching for acoustic modes in material systems of crystal acoustics (incl. thin films and fluids) and calculation of all relevant parameters
    - Extraction of material properties from BAW and SAW measurements
    - Calculation of COM parameters for SAW device simulation (surface impedance method)
    - SAW device simulation on base of different methods and models (surface impedance method, BAW based models)
    - FEM simulation of SAW systems
  • Customized ultra high frequency vibrometer for SAW & BAW wavefield measurements (Polytec UHF-120) with long-term stabilization and  capability for high temperature measurements
  • Dedicated clustertool CARMEN for thin film deposition on piezo- and pyroelectric substrates for magnetron sputtering, e-beam evaporation and pre-treatment including in-situ measurement techniques
  • High-precision ultrasonic pulse-echo measurement system (Ritec RAM-5000)
  • Customized laseracoustic devices (LAwave systems) for high-precision material characterization (bulk, thin films, temperature dependence)
  • Setup for high precision measurement of bulk sample mass densitity (single crystals etc.)
  • Brillouin light scattering measurement system (JRS)
  • Diverse setups for SAW-based microfluidics
  • In-situ measurement techniques for damage analysis on loaded SAW devices
  • Customized lifetime (TTF) measuring setups for SAW devices
  • Various ovens for thermal treatment and measurement up to 1600°C under different atmospheric conditions (vacuum, inert gas, forming gas)
  • Gas flow cryostats equipped for dielectric and ultrasonic measurements in the temperature range 4.2 K - 350 K
  • Diverse RF measurement devices up to 8.5 GHz (network analyzers, impedance/gain phase analyzers, digitizing oscilloscopes etc)
  • Equipment for measurement of electrical and mechanical thin film and bulk parameters (resistivity, polarization, pyroelectricity, hardness, thickness)