Abstract
Herein, we report the growth method of ultrathin indium nitride (InN) films on aluminum nitride (AlN) templates by sputtering and its application to field-effect transistors (FETs). Although island-like InN surfaces were formed at the initial film growth stage, the height of the islands on the surface could be controlled by changing the growth temperature. The height of the InN islands grown at 500 °C was lower than those grown at 440 °C and 480 °C. To demonstrate an application of the InN/AlN heterostructure to FETs, we fabricated FETs using a 2-nm-thick InN film grown on an AlN template. The FET with the InN channel grown at 500 °C exhibited a drain current density of 0.19 mA/mm and an on/off ratio of approximately 102 although the drain current of the FET with the InN grown at 450 °C was not adequately controlled by the gate bias. These results indicate that the growth condition of InN films is responsible for the characteristics of InN/AlN FETs.
Highlights
indium nitride (InN) has the smallest electron effective mass and the highest peak drift velocity and electron mobility among nitride semiconductors.1–9 Due to these remarkable properties, InN is an attractive material for high-speed or high-frequency devices
The full width at half maximum of the x-ray rocking curves (XRCs) for the 4-nmthick InN (∼300 arcsec) was comparable to that for the 50-nm-thick InN films, which indicates that highly c-axis oriented and ultrathin InN films can be grown on aluminum nitride (AlN) templates
Ultrathin InN films were grown on Al-polar AlN at various growth temperatures for the fabrication of InN/AlN field-effect transistors (FETs)
Summary
InN has the smallest electron effective mass and the highest peak drift velocity and electron mobility among nitride semiconductors.1–9 Due to these remarkable properties, InN is an attractive material for high-speed or high-frequency devices. InN films with a thickness of 1 nm–100 nm were grown on AlN templates by sputtering under various growth conditions.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
