Exploring Performance Variations in Bottom-Gated OTFTs: A Comparative Study of Top Contact vs. Bottom Contact Configurations under Parameter Variations

This study focuses on enhancing the operational efficiency of organic thin-film transistors (OTFTs), particularly in a bottom gate configuration. Leveraging Silvaco International's ATLAS™ TCAD software, we conducted numerical analysis of two-dimensional devices, manipulating channel length (L) from 10μm to 50μm. In the Bottom Gate Bottom Contact (BGBC) setup, drive current decreased from −1.4 × 10 ⁻¹⁰ A to −2.7 × 10 ⁻¹¹ A, impacting the current ratio from 1.2 × 10 ¹² to 1.4 × 10 ³ . Variations in organic semiconductor thickness (OSC) from 10nm to 50nm were also explored. The study analyzed key parameters, including mobility, on/off current ratio, and threshold voltage. Additionally, OTFT devices based on pentacene with a bottom-gate configuration were constructed, enabling comprehensive performance comparisons with contacts at the top and bottom.