High-performance, solution-processable semiconductors have drawn significant attention for use in low-cost, functional electronic applications. Metal oxide semiconductors are the most promising building blocks for high performance electronic devices because of their electrical properties and solution-processability. However, the major impediment for metal oxide semiconductors is that the electrical properties applicable to electronic devices are activated by chemical/physical structural evolution at high temperatures, which critically limits the practical applications. This article reviews the recent progress in the development of high-performance oxide semiconductors processed at low temperatures which are compatible with plastic substrates and discusses the chemical/physical approaches to lower the annealing temperature.