Large area electronics - Activities
Silicon Large Area Electronics
- We'd like to highlight the achievement of NMOS and PMOS TFTs based on μc-Si films produced by PECVD.
Organic Large Area Electronics
-The physical models were integrated in circuit simulators, thus connecting the device and system levels.
Modeling of Organic Diodes
Our numerical model is based on the following facts:
- Under reverse bias, the impedance response of the diode is that of a perfect capacitance, with a value that does not depend on the applied voltage. This is at variance with the conventional Schottky diode model, which predicts that the capacitance should vary as the reversed square root of the reverse bias.
- Organic semiconductors behave more like insulators than conventional semiconductors.
- Shortly, the organic diode is actually fully depleted at all bias.
Our model matured under three successive stages:
- Development of a simplified analytical equation.
- Numerical simulation with a software package that solves the two dimensional equations through finite element calculations.
- Validation of model results on real devices.
Modelling of Organic Field-effect Transistors (OFET)
The modelling of OFETs is performed at varous levels
- Analytical equations.
- Numerical simulation.
- Compact modelling.
Thanks to our approach we have found that the performance of OFETs is dictated by several basic parameters
The charge carrier mobility, which is several orders of magnitude lower than that of silicon.
- The mobility is significantly dependent on the density of charge carriers. In a OFET, it may have a primary effect on the modeling of the device.
The contact resistance. We have shown that in OFETs contact resistence largely depends on the configuration of its elements. In particular whether the source and drain are on the same side (planar) or on the opposite side (staggered) as the gate-dielectricsemiconductor interface.