Effect of In composition on electrical performance of AlInGaN/GaN-based metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) on Si

Al x In y Ga ( 1 − x − y ) N / GaN heterostructures were grown on 4-in. p-type Si wafers to investigate the effect of In composition in the quaternary nitride layer on the electrical performance of Al 2 O 3 / AlInGaN / GaN-based normally-ON metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs). From the comparative study of the electrical measurements, it was observed that the transport properties of the devices were relatively poor in the presence of higher In composition in the quaternary-N layer. The deterioration of the electrical characteristics of MIS-HEMTs originated from the formation of deep pits on the AlInGaN epilayer surface caused by the segregation of In atoms during epitaxial growth. However, the formation of such pits was reduced for the quaternary epilayer with lower In content and exhibited better transport performance. A maximum current density ( I d , m a x) of 780 mA/mm with a specific ON-resistance of 0.71 m Ω cm 2 was observed for the device fabricated on the wafer with an In composition of 9% in the AlInGaN epilayer. We have achieved a high breakdown voltage of 793 V with a device with the gate-to-drain distance ( L g d) of 20 μ m under the off-state condition. Al x In y Ga ( 1 − x − y ) N / GaN heterostructures were grown on 4-in. p-type Si wafers to investigate the effect of In composition in the quaternary nitride layer on the electrical performance of Al 2 O 3 / AlInGaN / GaN-based normally-ON metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs). From the comparative study of the electrical measurements, it was observed that the transport properties of the devices were relatively poor in the presence of higher In composition in the quaternary-N layer. The deterioration of the electrical characteristics of MIS-HEMTs originated from the formation of deep pits on the AlInGaN epilayer surface caused by the segregation of In atoms during epitaxial growth. However, the formation of such pits was reduced for the quaternary epilayer with lower In content and exhibited better transport performance. A maximum current density ( I d , m a x) of 780 mA/mm with a specific ON-resistance of 0.71 m Ω cm 2 was observed fo...