Analytical Model for Threshold-Voltage Shift in Submicron Staggered Organic Thin-Film Transistors

J. Pruefer, J.S. Leise (TH Mittelhessen Univ. of Applied Sciences, Germany and Univ. Rovira i Virgili, Spain), G. Darbandy (TH Mittelhessen Univ. of Applied Sciences, Germany), J.W. Borchert (Max Planck Inst. for Solid State Research and Univ. Stuttgart, Germany), H. Klauk (Max Planck Inst. for Solid State Research, Germany), B. Iniguez (Univ. Rovira i Virgili, Spain), T. Gneiting (AdMOS GmbH, Germany), A. Kloes (TH Mittelhessen Univ. of Applied Sciences, Germany)

This paper presents a compact model for the threshold-voltage shift, consisting of V_Troll-off and Drain- Induced-Barrier-Lowering (DIBL), in short-channel staggered organic thin-film transistors (OTFTs). An analytical surface potential solution is derived for a staggered geometry containing two-dimensional effects which is used to extract the V_Troll-off and DIBL out of it. Thus, the closed-form and physics-based equations extend an existing compact current model by incorporating them into expressions for VT. Verification of the modeling approach is done by comparison with TCAD Sentaurus simulations as well as measurements on organic TFTs with a channel length down to 400 nm.