Fabrication of an interdigitated sample holder for dielectric spectroscopy of thin films

6th International Conference on Optical, Optoelectronic and Photonic Materials and Applications 2014

Shenouda, Mina^1 ; Oliver, Derek R.^1

Department of Electrical and Computer Engineering, University of Manitoba, Winnipeg

MB

R3T 5V6, Canada^1

关键词: Adhesion layer;    Fabricated structures;    Finite element simulations;    Frequency dependent;    Fringing fields;    Function of frequency;    Impedance analyser;    Sample holders;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/619/1/012028/pdf
DOI  :  10.1088/1742-6596/619/1/012028

来源: IOP

【 摘 要 】

A planar interdigitated sample substrate has been designed to support a thin-film sample of a polymer while the frequency-dependent dielectric properties of the thin film are measured. Trenches for the electrodes were etched into a SiO2/Si wafer surface. Chromium was used as an adhesion layer prior to thermal evaporation of copper for the body of the electrode. The device was placed in a standard probe station and the dielectric character was recorded as a function of frequency with an impedance analyser. Devices with 20 to 70 fingers were measured and the results compared to analytical and finite element simulations. At 1 kHz, the total capacitance of a typical 20-finger device was 8 pF. The capacitive contribution of the thin film due to the fringing field in the polymer was about 2% of the total capacitance of the fabricated structures.