Frenkel defects experimental observation

Of the nine defect-pairs possible, only 5 have actually been experimentally observed in solids. These are Schottky, Frenkel,... 

Schottky devices have recently been fabricated by thermal evaporation of indium on polyaniline, poly(o-anisidine) and poly(aniline-co-or oanisidine), respectively [103]. The values of the rectification ratio, the ideality factor and the barrier height of an indium/poly(o-anisidine) have been experimentally determined as 300,4.41 and 0.4972, respectively. The observed deviation from the Schottky behaviour for these devices seen at higher voltages has been explained in terms of either the Poole-Frenkel effect or due to the presence of a large number of defects containing the trapped charges existing at the indium/poly (aniline-co-or oanisidine) interface. 

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