An improved-performance transparent organic thin-film transistor (OTFT) is described, which has a vanadyl-phthalocyanine (VOPc) film as an active p-channel, lattice-matched (Sc0.7Y0.3)(2)O-3 film as a high-k gate dielectric, and atomically flat indium tin oxide (ITO) film as the bottom contact (see Figure). These features-lattice matching and atomic flatness-are expected to lead to further improvements in transparent OTFTs.