Polarization Enhanced 2-Dimensional Electron Gas Properties with Single Crystal Yttrium Aluminium Nitride for Electronic Applications

The purpose of this research project is to investigate the epitaxial growth and the structural and 2-dimensional electron gas (2DEG) properties of a novel single crystal heterojunction Yttrium Aluminium Nitride/Gallium Nitride (YxAl1-xN/GaN) in a high-electron mobility transistor (HEMT).

This would be the first demonstration of heterostructures based on YAlN.Our goals are to the increase the electron concentration, lower the sheet resistance and to increase the electron confinement of the 2DEG. Total contact resistance will be reduced through re-grown n+-doped GaN contacts.

Epitaxial HEMT-layers will be grown on semi-insulation 4H-SiC, GaN-templates and AlN-substrates, and fabricated HEMTs will be characterized under application relevant condistions to asses the potential of the material.The project is organized in three work packages, Epitaxial growth, Material characterization, and HEMT-fabrication and characterization with clear goals on the electron transport properties of the 2-Dimensional Electon Gas.The III-Nitride semiconductor material system is today used in optoelectronic (LEDs), power electronic and high frequency electronics affecting us all.

Electrical power consumption and losses depend on the material properties.

Introducing Yttrium into the III-Nitride system could enhance the performance of the HEMT-devices and thus overall reduce the power consumption.