Fabrication of H-FET
Heterostructure field effect transistors (H-FETs) are powerful tools to investigate the transport properties of two-dimensional hole gases in germanium quantum wells. In this video, you will learn how H-FETs are made and show examples where measurements of H-FETs help us engineer better materials for qubits.
Prerequisite knowledge
- Basic understanding of semiconductor heterostructures
- Ohm’s law
- Concepts of mobility and percolation density
Main takeaways
- Hall bar shaped heterostructure field effect transistor are devices similar to transistor, but comprise multiple ohmic contacts
- Electrical characterization of H-FETs at low temperature is a crucial part of the feedback loop to optimize germanium quantum wells
Further thinking
True or false: Do H-FETs with germanium quantum wells require ion implantation for making ohmic contacts?
Further reading
G. Scappucci et al. The germanium quantum information route. Nat Rev Mater 6, 926–943 (2021). https://doi.org/10.1038/s41578-020-00262-z
Sammak et al Adv. Funct. Mater, 29, 1807613 (2019) https://doi.org/10.1002/adfm.201807613
L. E. A. Stehouwer et al Appl. Phys. Lett. 123, 092101 (2023) https://doi.org/10.1063/5.0158262