Ultra-high gain diffusion-driven organic transistor

Emerging large-area technologies based on organic transistors are enabling the fabrication of low-cost flexible circuits, smart sensors and biomedical devices. High-gain transistors are essential for the development of large-scale circuit integration, high-sensitivity sensors and signal amplification in sensing systems. Unfortunately, organic field-effect transistors show limited gain, usually of the order of tens, because of the large contact resistance and channel-length modulation. Here we show a new organic field-effect transistor architecture with a gain larger than 700. This is the highest gain ever reported for organic field-effect transistors. In the proposed organic field-effect transistor, the charge injection and extraction at the metal–semiconductor contacts are driven by the charge diffusion. The ideal conditions of ohmic contacts with negligible contact resistance and flat current saturation are demonstrated. The approach is general and can be extended to any thin-film technology opening unprecedented opportunities for the development of high-performance flexible electronics

A Review of Fully Integrated and Embedded Power Converters for IoT

The Internet of Things (IoT) has found application in many components of implantable medical devices, wearable smart devices, monitoring systems, etc. The IoT devices are conventionally battery powered, even though, in several low power applications, they can also be powered using energy harvesting technology. Independently of the power sources (if batteries or environment), efficient and robust power converters must be designed to provide the small and distributed energy required by such IoT devices. This review paper will first provide an overview about the power consumption in IoT devices; second, it will discuss the most recent research and advance in the field of fully-integrated or embedded DC/DC converters, starting from high-performance integrated charge pumps or embedded inductive boost converters for specific harvesting sources (temperature, solar, and so on), to novel DC/DC converters for multiple energy sources