Organic Permeable Base Transistors – Insights and Perspectives

Abstract

Vertical organic transistors have emerged as a new device concept holding great promise to overcome the limitations of lateral organic transistors. In this regard, the organic permeable base transistor (OPBT), a special kind of vertical transistor, stands out due to excellent performance figures such as low-voltage operation and high transition frequency measured in a pulse-biasing mode. On the occasion of Prof. Karl Leo's 60th birthday, his contributions to the development of high-performance OPBTs are honored and a perspective for the future of OPBT development is provided. The current state of the art of OPBTs is reviewed and the principles of the device operation are summarized. New insights into the formation of the permeable base layer, which is vital to the function of OPBTs, are discussed. Additionally, a full yield analysis on a batch of 144 equivalent OPBTs is reported and the device yield and temporal evolution of device parameters are statistically analyzed. This analysis proves a device yield of >90% for these short-channel transistors, rendering the possibility for circuit integration. Finally, the scaling laws of OPBTs are derived and strategies for new materials and device layouts to push the performance to the gigahertz regime are concluded.