Cytocompatible, disintegrable, low-voltage operation n-type organic thin film transistors†

Abstract

The constant demands for the better performance of consumer electronics have led to shorter usage lifespans, resulting in a significant increase in electronic waste (e-waste). Developing electronics that can be easily broken down and recycled is a promising strategy to tackle this growing e-waste challenge. Herein, we report a biocompatible and degradable organic thin film transistor (OTFT) utilizing a biocompatible semiconductor with a biodegradable dielectric and substrate. We present the first OTFT based on bispentafluorophenoxy silicon phthalocyanine (F₁₀-SiPc) integrated with a polyvinyl alcohol (PVA) and poly(caprolactone) (PCL) bilayer as the dielectric, leading to a drop in threshold voltage (V_T) from 12.7 V to −0.97 V, versus using SiO₂ while maintaining similar mobility values. We demonstrate the importance of the annealing temperature on PLA substrate roughness and gate electrode surface chemistry for the fabrication of working OTFT devices. We then demonstrate that the bendable OTFTs could easily be dissolved in phosphate buffer saline (PBS) solution at room temperature in less than a month, which is a crucial aspect for ensuring eco-sustainability in electronic devices. Finally, incubation of the degradation products with fibroblastic cells did not affect cell viability, suggesting that they are non-cytotoxic. These cytocompatible disintegrable OTFTs with low operating voltages will find applications in bioresorbable electronics and constitute a step towards minimizing e-waste.