Novel high performance AlGaN/GaN based enhancement‐mode metal‐oxide semiconductor high electron mobility transistor

This paper presents first results of a new high performance enhancement‐mode (E‐mode) gallium nitride (GaN) based metal‐oxide semiconductor high electron mobility transistor (MOS‐HEMT) that employs an ultrathin 3 nm aluminium gallium nitride (Al0.25G0.75aN) barrier layer and relies on an induced two dimensional electron gas (2DEG) for operation. Devices have been demonstrated on both sapphire and silicon substrates. Single finger devices on a sapphire substrate were fabricated using 10 nm and 20 nm, and on a silicon substrate using 30 nm of plasma enhanced chemical vapour‐deposited (PECVD) silicon dioxide (SiO2) as the gate dielectric. They demonstrated threshold voltages of +3 V, +2 V, +0.8 V and very high maximum drain currents of over 620 mA/mm, 550 mA/mm and 450 mA/mm, respectively. These results show that the proposed device concept can be a building block for future power electronic devices. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)