Novel AlAs-InGaAs-AlAs Resonant Tunnelling Diodes for THz

点击翻译按钮获取中文摘要

The Double-Barrier Quantum Well(DBQW) RTD is considered as the most promising candidate for high-speed functionaldevices and THz oscillators at room temperature. For THz oscillators, the highestfrequency of electronic single devices at room temperature reported recently (2016)is 1.9THz holding much promise for the realisation of compact and efficient electronicTHz oscillatorsThe DBQW-RTD in its simplest form, consists of a few monolayers undoped quantumwell sandwiched between two undoped layer of barriers of thickness 3 monolayers.The emitter and collector contact regions are heavily doped. One of the keytechnologies for this achievement is the precise control of epitaxial growth of ultrathinsemiconductor heterostructures. The structural design of oscillators andmicrofabrication technology are also crucial. To achieve oscillations in the terahertzregime, this programme will examine a novel RTD structure designs with ultra thinAlAs tensile barriers and highly compressive InGaAs quantum wells, which effectivelyreduces both the operating bias voltage and electron transit time in the collectordepletion region. InGaAs/AlAs RTD oscillator with 0.9-nm-thick barriers will bestudied for fundamental oscillations at frequencies > 1 THz at room temperature. Thisprogramme will examine the integration of RTDs with RF circuits to form completenarrow band emitters in the THz region for use as high power emitters in CW THzimaging systems.