In0.53Ga0.47As based metal oxide semiconductor capacitors with atomic layer deposition ZrO2 gate oxide demonstrating low gate leakage current and equivalent oxide thickness less than 1 nm

The paper demonstrates properties of metal oxide semiconductor capacitors fabricated on molecular beam epitaxial In(0.53)Ga(0.47)As wafers with the atomic layer deposition ZrO(2) gate oxide. The equivalent oxide thickness of 0.8 nm was obtained for 5 nm thick ZrO(2), while the gate leakage current density at V(FB)+1 V was as low as 0.1 A/cm(2). Sensitivity of capacitance-voltage characteristics to the metal gate work function along with low frequency dispersion of similar to 5%/decade served as a strong evidence of a nonpinned Fermi level at the oxide-InGaAs interface. Both electrical and structural properties remain stable up to 800 degrees C. (c) 2008 American Institute of Physics.