The demand for flexible and inexpensive wireless communications and applications has sparked interest in innovation in wireless energy collection. For example, scientists were able to use organic material for a new semiconductor design for radio frequency circuits. Notably, organic semiconductors have applicability in 5G applications, according to international scientists led by King Abdullah University of Science and Technology (KAUST).
Basic Principles
Although organic semiconductors share the same physical properties as their inorganic counterparts, such as silicon-based semiconductors, there are significant differences. Read also : RF Plasma Generator Market To Reach US$ 5.1 Billion By 2031, TMR. One difference is that inorganic semiconductor molecules are joined by weak van der Waals interactions, and organic semiconductors are maintained by covalent bonds.
This distinction highlights variations in the properties of devices that use organic and inorganic semiconductors. In this regard, organic semiconductors are made using solvent-based processing techniques that make them cheaper and more flexible to print or use in sheet and die coating, Ph.D. student Kalaivanan Loganathan.
On the downside, electric charges move much more slowly in organic materials. This hindrance is a barrier to the application of organic semiconductors for use in fast applications, such as radio frequency electronics, the scientists said.
“For this technology to be useful for the 5G frequency band, Schottky organic diodes need to be manufactured,” Loganathan said.
The Schottky diode allows current to flow in one direction, but blocks in the other. The most important difference between the ubiquitous p-n diode and the Schottky diode is that the latter can change from a conductive state to a non-conductive state much faster. This makes them essential in radio frequency applications.
They explain that the speed of Schottky diodes is generally limited by the capacity and resistance of the device. But organic semiconductors are often associated with high capacity and endurance due to low load carrier mobility, the authors said. They are mostly used in traditional sandwich-type architecture, where semiconductors, metals, and electrical contacts are stacked on top of each other.
Reimagined for the 5G Frequency Range Loganathan, working with Professor Thomas Anthopoulos and his team, he redesigned the device’s architecture and put the two electrical connections aside. The organic semiconductor, called C16IDT-BT, was placed in a small gap of 25 nanometers between the diodes. The diodes in this structure have very low capacitance and resistance.
Scientists have shown that the Schottky diode operates at a frequency of 6 GHz (6 billion cycles per second). The frequency was extended to 14 GHz by chemically doping the semiconductor, adding another molecule.
“Our results show that organic semiconductors are capable of operating in the 5G frequency range, just like their inorganic counterparts,” Loganathan said, adding that these organic semiconductors can be manufactured at low cost using solution processing.
The group said they hope to integrate their diodes into radio frequency circuits, ID tags and wireless power storage devices.
The findings were published in the journal Advanced Materials.
