2020 Technology Roadmap of solid-state Terahertz source device technologies

Abstract

The aim of this thesis is to review the Radio Frequency (RF) sources leading to Terahertz source technologies that operate at room temperature and are based on solid-state devices technologies and have light weight and mass manufactureable for growing wireless technologies such as 5G and beyond. This review study has enabled us to predict a 2020 roadmap to predict the future development and progress that is anticipated in terms of these source technologies to estimate the output power frequency capabilities these sources. We have identified three such source technologies and they are planar Gunn diode, Impact ionization avalanche Transit-Time diode (IMPATT) diode and resonant tunnelling diode (RTD). We find two remarkable trends for planar Gunn diode and Resonant Tunnelling Diodes. The planar Gunn diode is predicted to reach an output RF power of 110dBm & 1THz fundamental mode of operation by 2040 compared to current state of the art performance of -5dBm and 300GHz frequency of oscillations. In case of RDT a remarkable frequency of oscillations of 5.2THz and output power of 9.7dBm by 2040 from current state of the art performance of 1.9THz and 0dBm output power. This means without some significant breakthroughs the future researcher will find powerful RF sources for 5G and 6G technologies. Although there are other Terahertz solid-state sources able to produce higher output power such as THz quantum cascade lasers (QCLs), vacuum tube based sources. However, they are bulky, some needs cryogenic cooling and some are not mass producible and most of all they are expensive to use in commercial applications. The program of this research was in collaboration with the Cranfield University.