Epitaxial LiNbO₃ thin films grown by the "eclipse method"

LiNbO₃ thin films were grown by pulsed laser deposition (PLD) with a shadow mask, which is called the "eclipse method". Epitaxial twin-free films were obtained using a single crystal target without a postannealing process. The films had very smooth surface without the particulate problem, which is common in films grown by conventional PLD. The root-mean-sqaure surface roughness was only 3 nm, and optical propagation loss was as low as 3 dB/cm.