Removal of hexavalent chromium by Zn(ii) dithiocarbamate/ZnS nanocomposite.

In this study, GaAs metal–oxide–semiconductor (MOS) capacitors using Y‐incorporated TaON as gate dielectric have been investigated. Experimental results show that the sample with a Y/(Y + Ta) atomic ratio of 27.6% exhibits the best device characteristics: high k value (22.9), low interfacestate density (9.0 × 1011 cm–2 eV–1), small flatband voltage (1.05 V), small frequency dispersion and low gate leakage current (1.3 × 10–5A/cm2 at Vfb + 1 V). These merits should be attributed to the complementary properties of Y2O3 and Ta2O5:Y can effectively passivate the large amount of oxygen vacancies in Ta2O5, while the positively‐charged oxygen vacancies in Ta2O5 are capable of neutralizing the effects of the negative oxide charges in Y2O3. This work demonstrates that an appropriate doping of Y content in TaON gate dielectric can effectively improve the electrical performance for GaAs MOS devices.

GaAs metal–oxide–semiconductor (MOS) capacitors with NbAlON gate dielectric are fabricated with LaAlON or LaON as interface passivation layer and compared with their counterpart without interface passivation layer. Experimental results show that improvements in electrical properties and reliability are achieved, especially for the sample with LaAlON passivation layer (the hygroscopicity of LaON is largely reduced by Al incorporation): relatively high k value (25.5), low interface‐state density (6.8 × 1011 cm−2 eV−1), small flatband voltage (0.67 V), small hysteresis (45 mV), small frequency dispersion and low gate leakage (6.18 × 10−6 A cm−2 at Vfb + 1 V). These should be attributed to the suppressed growth of unstable Ga and As oxides on the GaAs surface and reduced in‐diffusion of elements from the gate dielectric to the GaAs surface by the LaAlON passivation layer during gate‐dielectric annealing.