A practical operational amplifier circuit is formed using thing film transisters. An operational amplifier circuit is formed by thin film transistors formed on a quartz substrate wherein cumulative distribution of mobilities of the n-channel type thin film transistors becomes 90% or more at 260 cm2/Vs and wherein cumulative distribution of mobilities of the p-channel type thin film transistors becomes 90% or more at 150 cm2/Vs. The thin film transistors have active layers formed using a crystalline silicon film fabricated using a metal element that selected to promote crystallization of silicon. The crystalline silicon film is a collection of a multiplicity of elongate crystal structures extending in a certain direction, and the above-described characteristics can be achieved by matching the extending direction and the moving direction of carriers.