Researchers develop switchable organic material that could slash costs for flexible electronics
Scientists created a single organic material that flips between conducting and insulating states using electrical fields, potentially enabling cheaper, more flexible semiconductor devices for large-scale manufacturing. The advance could lower production costs for next-generation displays, memory devices, and wearable electronics by replacing expensive multi-layer components with one adaptable material.
Originaltitel: Switchable Charge Injection Barrier in an Organic Supramolecular Semiconductor
<p>We disclose a supramolecular material that combines semiconducting and dipolar functionalities. The material consists of a discotic semiconducting carbonyl-bridged triarylamine core, which is surrounded by three dipolar amide groups. In thin films, the material self-organizes in a hexagonal columnar fashion through Jr-stacking of the molecular core and hydrogen bonding between the amide groups. Alignment by an electrical field in a simple metal/semiconductor/metal geometry induces a polar order in the interface layers near the metal contacts that can be reversibly switched, while the bulk material remains nonpolarized. On suitably chosen electrodes, the presence of an interfacial polarization field leads to a modulation of the barrier for charge injection into the semiconductor. Consequently, a reversible switching is possible between a high-resistance, injection-limited off-state and a low-resistance, space-charge-limited on-state. The resulting memory diode shows switchable rectification with on/off ratios of up to two orders of magnitude. This demonstrated multifunctionality of a single material is a promising concept toward possible application in lowcost, large-area, nonvolatile organic memories.</p>