Smallest terahertz wave oscillation and detection devices

ROHM offers samples of the industry’s smallest terahertz (THz) wave oscillation and detection devices using semiconductor elements known as resonance tunnelling diodes (RTDs). Terahertz waves are expected to be applied to non-destructive testing, imaging, and sensing in the medical and healthcare sectors and possibly future ultra-fast communication technologies. Supplying these devices contributes to the advancement of terahertz wave applications.

The company has developed a 0.5mm × 0.5mm RTD chip for terahertz wave generation and detection, capable of oscillating and detecting terahertz waves at a frequency of 320GHz (typ.) with an output power ranging from 10µW to 20µW. ROHM will begin offering samples of this RTD element mounted in a PLCC package (4mm × 4.3mm) typically used for LEDs. With an extremely compact size, generally one-thousandth of that of conventional oscillators, this innovation allows easy development of terahertz wave applications, even in space-constrained environments.

By positioning the antenna surfaces of the oscillation and detection devices facing each other 10mm apart, a dynamic range of 40dB (typ.) can be achieved. The oscillator and detector maintain a drive power consumption of 10mW (typ.), while their ability to oscillate and detect terahertz waves at room temperature eradicates the necessity for cooling equipment needed with some conventional methods. These compact, power-saving devices are almost unaffected by the operating environment, allowing usage in various applications.

The company offers samples of terahertz wave oscillation and detection devices less than one-tenth the price of conventional devices. It also supplies evaluation kits with an evaluation board and other components, allowing users to integrate the devices into a research and development environment easily. The sale of sample products and evaluation kits needs the prior signing of a non-disclosure agreement (NDA) with ROHM.

Professor Safumi Suzuki, Laboratory for Future Interdisciplinary Research of Science and Technology, Institute of Integrated Research, Institute of Science Tokyo, said: “Terahertz waves are expected to be applied to various fields such as imaging, sensing, and wireless communications due to their excellent characteristics and high degree of safety. However, research and development for commercialisation has traditionally required large-scale equipment and substantial costs. In this context, the RTD terahertz wave device – developed through years of collaborative research with ROHM – is an ultra-small 4mm × 4.3mm device that challenges conventional norms while featuring astonishingly low power consumption and implementation costs. With the launch of device samples, we anticipate that many private companies and research institutions will begin exploring terahertz wave research. We hope that the use of terahertz waves in various fields will lead to the creation of new applications with functions that were previously difficult to achieve. Going forward, we will continue to contribute to society through the development of terahertz wave devices in partnership with ROHM.”

Ken Nakahara, general manager of ROHM Research & Development Center, ROHM Co., Ltd., said: “The terahertz R&D team and I are very excited and proud to have reached the point where we can bring this technology to market. We have dedicated ourselves to THz devices for about 15 years; the journey has not been easy. We gathered the forces of industry, academia, and government along the way, and have successfully established the position that ROHM holds today. The team understands that this announcement is just a small step toward the commercialisation of THz technology, but at the same time, it is a giant leap for us. We believe that this small beginning will grow big and contribute to the well-being of our society.”