Furthermore, new transistor designs such as vertical devices are introduced to benefit from drastically reduced channel length while keeping the effort for structuring moderate.  Here, we show that a strong electrothermal feedback occurs in organic transistors, ultimately leading to output characteristics with regions of S-shaped negative differential resistance.  For that purpose, we use an organic permeable-base transistor (OPBT) with outstanding current densities, where a strong and reproducible, non-linear electrothermal feedback is revealed. 
THERM