InAs/AlGaSb heterostructures have favourable properties for high speed devices with low power consumption which promise to provide superior performance compared to devices based on other material systems. Already field effect transistors and other electronic devices using InAs/AlGaSb heterostructures have been realised and it has been demonstrated that the relevant device parameters for high speed applications reflect the excellent intrinsic properties of this semiconductor. However, field effect transistors realised so far do still not make use of all advantages of InAs/AlGaSb. The reason can be seen in the insufficiently developed technology of fabrication and processing of devices with this new material system.
The specific project is to fabricate and study field effect transistors that make use of the latest developments in material research on InAs/AlGaSb, thereby bridging the areas of fundamental physics and device applications.
Following on the demonstration of state-of-the-art mobility in this material system in our group heterostructures that show the combination of highest mobility and carrier concentration are processed using photo- and electron beam lithography. The fabricated devices are examined with electrical and spectroscopic characterisation techniques. The experimental work is completed with modelling and simulation of the devices. The correlation between fabrication techniques and device performance is studied in order to find conditions for an optimal exploitation of the properties of InAs/AlGaSb for high speed field effect transistors with low power consumption.