National and Kapodistrian University of Athens Semiconductor and Microsystems Laboratory Solid State Physics Section Department of Solid State Physics Department of Solid State Physics, Faculty of Physics, University of Athens University of Athens, School of Science, Faculty of Physics, Department of Solid State Physics, Contact, Maps Penepistimiopolis Zografos, Athens 15784 | Phone: +30 210 7276-722 | Fax: +30 210 7276-711 Semiconducting Materials Semiconductor Devices MEMS Nanocomposites Reliability     Materials and     Transport parameters     Point defects     Dielectric films Dielectric films Material research Aim of this activity is to investigate the electrical properties of a wide range of dielectric materials that find application in both the semiconductor devices and MEMS switches. The dielectric materials the group investigates are: *   Plasma Enhanced Chemical Vapor Deposited (PECVD) Silicon Nitride. The group investigated the impact of deposition conditions such as plasma frequencey (13.56MHz,  380KHz or mixed frequency), the substrate temperature rnaging from 100^oC to 350^oC, the gas ratio composition etc, since all these directly affect the material nanostructure. *   PECVD Silicon Nitride with nanostructures embeded in the host materials *   PECVD Silicon Dioxide *   Nano/micro crystalline diamond *   AlN and Al₂O₃ *   Transition metal oxides such as TiO₂, Y₂O₃, HfO₂, etc *   varius PZT dielectrics The test structure to assess the dielectric materials are the Metal-Insulator-Metal (MIM) capacitors with different geometries. The parameters tested are: *   Current-Voltage characteristics *   Thermally Stimulated Depolarization/Polarization Currents (TSDC/TSPC) method to investigated point and extended defects *   Charge/Discharge Current Tranient method to monitor the charge/discharge transients in MIM capacitors *   Capacitance-voltage characteriszation to monitor the exchange of charges with the dielectric film and the dependence on test signal frequencey *   Kelvin Probe method to monitor the surface potential of dielectric films and/or the potential of top electrode in MIM capacitors *   All assessment performed  in the temperature range of 90 K to 450 K Experimental setup The experimental setup consists of: *  TSDC/TSPC setup * CCT/DCT * Kelvin Probe setup * Keithley 6485, 6487 and 6517A pico-Amperemeters for the current-voltage  characterization in MIM capacitors *  Kelvin Probe setup *  Probe station with Cascade micromanipulators in dark box for on wafer assessment *  Cascade Microtech RF-1 probe station with Pico-Probe CPW probes *  All measurements are computer controlled with Labview software. MIM capacitors with different geometries Distribution of time constants in energy domain for PECVD Silicon Nitride