Electrochemical anodizing techniques for structuring of high-performance vertical organic field-effect transistors

Vertical organic transistors are an attractive alternative for short channel transistors, in particular, vertical organic permeable base transistors can achieve record-high transition frequencies of up to 40 MHz and drive large current densities of kA cm-2. Here, we design a novel architecture for vertical organic field-effect transistors (VOFETs) with superior electrical performance and simplified low-cost processing. By using electrochemically oxidized aluminum oxide as the charge blocking layer in VOFETs, direct leakage current paths between source and drain can be effectively suppressed, enabling VOFETs with a high on-off ratio and exceptional transconductance. Our anodization technique is easy to be realized and can be readily used on both n-type and p-type organic semiconductor thin films to achieve high-performance VOFETs, opening a new pathway to build, e.g. complementary circuit composed of vertical organic transistors.