AlGaN/GaN high electron mobility transistors(HEMTs)with high performance were fabricated and characterized.A variety of techniques were used to improve device performance,such as AlN interlayer,silicon nitride passi...AlGaN/GaN high electron mobility transistors(HEMTs)with high performance were fabricated and characterized.A variety of techniques were used to improve device performance,such as AlN interlayer,silicon nitride passivation,high aspect ratio T-shaped gate,low resistance ohmic contact and short drain-source distance. DC and RF performances of as-fabricated HEMTs were characterized by utilizing a semiconductor characterization system and a vector network analyzer,respectively.As-fabricated devices exhibited a maximum drain current density of 1.41 A/mm and a maximum peak extrinsic transconductance of 317 mS/mm.The obtained current density is larger than those reported in the literature to date,implemented with a domestic wafer and processes.Furthermore, a unity current gain cut-off frequency of 74.3 GHz and a maximum oscillation frequency of 112.4 GHz were obtained on a device with an 80 nm gate length.展开更多
The paper reports that Hfrio dielectric is deposited by reactive co-sputtering of Hf and Ti targets in an Ar/O2 ambience, followed by an annealing in different gas ambiences of N2, NO and NH3 at 600℃ for 2 min. Capac...The paper reports that Hfrio dielectric is deposited by reactive co-sputtering of Hf and Ti targets in an Ar/O2 ambience, followed by an annealing in different gas ambiences of N2, NO and NH3 at 600℃ for 2 min. Capacitancevoltage and gate-leakage properties are characterized and compared. The results indicate that the NO-annealed sample exhibits the lowest interface-state and dielectric-charge densities and best device reliability. This is attributed to the fact that nitridation can create strong Si≡N bonds to passivate dangling Si bonds and replace strained Si-O bonds, thus the sample forms a hardened dielectric/Si interface with high reliability.展开更多
文摘AlGaN/GaN high electron mobility transistors(HEMTs)with high performance were fabricated and characterized.A variety of techniques were used to improve device performance,such as AlN interlayer,silicon nitride passivation,high aspect ratio T-shaped gate,low resistance ohmic contact and short drain-source distance. DC and RF performances of as-fabricated HEMTs were characterized by utilizing a semiconductor characterization system and a vector network analyzer,respectively.As-fabricated devices exhibited a maximum drain current density of 1.41 A/mm and a maximum peak extrinsic transconductance of 317 mS/mm.The obtained current density is larger than those reported in the literature to date,implemented with a domestic wafer and processes.Furthermore, a unity current gain cut-off frequency of 74.3 GHz and a maximum oscillation frequency of 112.4 GHz were obtained on a device with an 80 nm gate length.
基金Project supported by the National Natural Science Foundation of China (Grant No 60376019).
文摘The paper reports that Hfrio dielectric is deposited by reactive co-sputtering of Hf and Ti targets in an Ar/O2 ambience, followed by an annealing in different gas ambiences of N2, NO and NH3 at 600℃ for 2 min. Capacitancevoltage and gate-leakage properties are characterized and compared. The results indicate that the NO-annealed sample exhibits the lowest interface-state and dielectric-charge densities and best device reliability. This is attributed to the fact that nitridation can create strong Si≡N bonds to passivate dangling Si bonds and replace strained Si-O bonds, thus the sample forms a hardened dielectric/Si interface with high reliability.