Nitrided HfTiON/Ga₂O₃(Gd₂O₃) as stacked gate dielectric for GaAs MOS applications

Abstract

GaAs metal–oxide–semiconductor (MOS) capacitors with HfTiON as a gate dielectric and Ga2O3(Gd2O3) (GGO) as an interlayer annealed in NH3 or N2 are fabricated, and their electrical properties are characterized. Experimental results show that the HfTiON/GGO/GaAs MOS device annealed in NH3 exhibits a low interface-state density (1.1 × 1012 cm−2 eV−1), a small gate leakage current (1.66 × 10−4 A cm−2 at Vg = Vfb + 1 V), a large equivalent dielectric constant (25.7), and a good capacitance–voltage behavior. All these should be attributed to the fact that the GGO interlayer and postdeposition annealing in NH3 can effectively suppress the formation of interfacial Ga/As oxides and remove the excess As atoms at the GaAs surface, thus reducing the relevant defects at/near the GGO/GaAs interface.

Determination of optical constant and electrical properties of sputtering-derived HfTiON gate dielectrics

“…However, the Hf-Ti oxide composition should be optimized aiming at simultaneous enhancement of the dielectric constant and preservation of an interface barrier height sufficient to prevent electron tunneling because of the lower band-gap of TiO 2 compared with HfO 2 . In this paper, the TiO 2 concentration was fixed at 9% in consideration of the suitable band offsets relative to Si as well as applicable permittivity [13][14][15]. Currently, it has been reported that nitrogen incorporation into Hf-based high k gate dielectrics, such as HfON, HfAlON and HfLaON, have been focused to meet the urgent need for advanced MOS device applications because it can effectively lessen the gate leakage current, enhance the crystallization temperature, reduce charge trapping, and further scale down the equivalent oxide thickness (EOT) [16][17][18][19].…”

Improved Electrical Properties and Reliability of GaAs Metal-Oxide-Semiconductor Capacitor by Using LaAlON Passivation Layer

“…Owing to the advantages of La 2 O 3 mentioned above, especially its good interfacial quality with GaAs, La‐based high‐ k materials have attracted much attention for passivating the surface of GaAs. The comparison of D it , hysteresis and gate leakage of GaAs MOS devices with sputtering deposited gate dielectric stacks between this work and recent reports with different interfacial passivation layers and gate dielectrics are listed in Table S1 (see more details in supporting information). Obviously, La‐based high‐ k materials are more suitable for the IPL, with the one in this work achieving the lowest D it and gate leakage.…”

Characteristics of In0.7Ga0.3As MOS Capacitors with Sulfur and Hydrazine Pretreatments

“…Specifically, improved C-V behaviors with less frequency dispersion in the accumulation region and steep slope in the depletion regime are demonstrated for sample C, indicating fewer interface states and Femi-level pinning effects at the high-κ/In 0.7 Ga 0.3 As interface. 9,34,35 This can be attributed to the fact that the N 2 H 4 treatment can reduce the As-As, In-O, Ga-O, and As-O bonds at the high-κ/In 0.7 Ga 0.3 As interface while strong N-related covalent bonds formed.…”