Abstract
A photopolymer based Al/NOA60/p-Si (metal-polymer-semiconductor) MPS device was fabricated and the current transport properties were investigated by using the forward bias current-voltage (I-V) characteristic in the temperature range of 80-300 K. The cross-sectional structure of polymer/semiconductor was revealed by the scanning electron microscope (SEM) image and it was seen that the NOA60 photopolymer was tidily coated on the p-Si surface. According to the I-V measurements at room temperature, the MPS device exhibits a good rectification ratio of 8140 at ±1V. Temperature-dependent I-V measurements (I-V-T) were analyzed on the basis of thermionic emission (TE) theory and an abnormal increase in zero-bias barrier height (BH) and a decrease in ideality factor (n) was observed with increasing temperature. Additionally, two different linear regions with distinct values from the theoretical value of the Richardson constant (A*) were observed in the conventional Richardson plot. Such deviations from ideal TE theory has been attributed to the effect of BH inhomogeneities. Gaussian distribution (GD) of BH model has applied the I-V-T results and double GD BH with mean values of 0.75±0.08 eV (80 – 140 K) and 1.02±0.11 eV (140 – 300 K) were calculated. Moreover, the A* value of 64.73 A/cm2K2 was calculated close to the known value of p-Si from the modified Richardson plot. Thus, it has been concluded that the current transport of the Al/NOA60/p-Si MPS device can be explained by TE with double GD BH model for a wide temperature region.
Polymer source-gated transistors with low saturation voltage
