Ultrathin Barrier AlGaN/GaN Heterostructure: A Recess Free Technology for Manufacturing High Performance GaN on Si Power Devices
(Al)GaN recess free normally OFF technology is developed for fabrication of high yield lateral GaN based power devices. The recess free process is achieved by an ultrathin barrier (UTB) AlGaN/GaN heterostructure that features a natural pinched off 2 D electron gas channel. The top down manufacturing technique overcomes the challenges in etching of AlGaN barrier with well controlled depth and uniformity, which is especially attractive for fabrication of normally OFF GaN based high electron mobility transistors (HEMTs) and metal insulator semiconductor HEMTs (MIS HEMTs) on large size Si substrate. With SiNx passivation grown by low pressure chemical vapor deposition, on resistance of the UTB AlGaN/GaN based power devices can be significantly reduced. High uniformity low hysteresis normally OFF HEMTs and Al2O3/AlGaN/GaN MIS HEMTs are successfully demonstrated on the UTB AlGaN/GaN on Si platform. It is also a compelling technology platform for manufacturing high performance GaN based lateral power diodes, and normally OFF p (Al)GaN heterojunction field effect transistors.
IEEE Transactions on Electron Devices