Degradation mechanisms of electron mobility in metal-oxide-semiconductor field-effect transistors with LaAlO3 gate dielectric

作者：Chang Ingram Yin ku^*; You Sheng wen; Chen Main gwo; Juan Pi chun; Chen Chun heng; Lee Joseph Ya min

来源：Journal of Applied Physics, 2009, 105(10): 104512.

DOI：10.1063/1.3129687

LaAlO3 is a promising candidate of gate dielectric for future very large scale integration devices. In this work, metal-oxide-semiconductor capacitors and transistors with LaAlO3 gate dielectric were fabricated and the electron mobility degradation mechanisms were studied. The LaAlO3 films were deposited by radio frequency magnetron sputtering. The LaAlO3 films were examined by x-ray diffraction, secondary ion mass spectroscopy, and x-ray photoelectron spectroscopy. The temperature dependence of metal-oxide-semiconductor field-effect transistors characteristics was studied from 11 K to 400 K. The rate of threshold voltage change with temperature (Delta V-T/Delta T) is -1.51 mV/K. The electron mobility limited by surface roughness is proportional to E-eff(-0.66) in the electric field of 0.93 MV/cm < E-eff < 2.64 MV/cm at 300 K and the phonon scattering is proportional to T-5.6 between 300 and 400 K. Soft optical phonon scattering was used to explain the extra source of phonon scattering in LaAlO3-gated n-channel metal-oxide-semiconductor field-effect transistors.

• 出版日期2009-5-15
• 单位中国科学院电工研究所; 清华大学