Evaluation of the electric field in thin insulating layers using a thermal stimulus technique

Researchers : A. Oukms (PHD student), P. Notingher (Professor), S. Agnel (MCF), J-C. Laurentie (MCF), O. Guille (ASI)

Duration : 3 years (2017-2020)

The Energy and Materials Group of the IES is at the origin of a method based on the application of a low temperature step, to determine the distribution of charges and electric fields in materials and insulating structures. This stimulus is particularly suitable for thicknesses ranging from several hundred microns to several tens of millimetres. In order to deepen the study of the accumulation of space charges near the insulator/conductor or insulator/semiconductor interfaces, this work aims, on the one hand, to improve the knowledge of the temperature on the surface of the sample in contact with the temperature source, and secondly the optimization of the heat transfer from the source to the sample.

After a literature review on measurement methods and temperature sensors, we focused on the realization and characterization of a large-area, high-dynamic, electrically insulated, low-surface thermal sensor (bolometer) signal-to-noise ratio. On the other hand, to allow analysing the influence, on the measurement signals, of the distribution of the charges in the insulator and the thermal interfaces between the temperature source and the sample, a tool of simulation and of numerical analysis has been developed. The rest of the work will include experimental studies to be performed on a device under development, which will be coupled with simulations and modelling of electrostatic and thermal phenomena to optimize the tool and increase its accuracy.