In this letter, high-performance, highly transparent amorphous InGaZnO (IGZO) thin-film transistors (TFTs) with IGZO source/drain electrodes were fabricated. Rapid thermal annealing treatment effectively converted IGZO from a semiconductor into a conductor. Using a patterned SiO2 capping layer, highly transparent IGZO-TFTs with selectively formed IGZO electrodes were fabricated on a glass substrate. The mobility of the fabricated IGZO-TFT was 8.3 cm2/V s, ON/OFF ratio was 3.1 × 106, and subthreshold swing was 0.44 V/decade. Thus, the proposed scheme provides a simple and practical method of fabricating high-performance, highly transparent IGZO TFTs.