WAVEGUIDE TYPE OPTICAL CONTROL DEVICE AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a waveguide type optical control device in which switching voltage is lowered without increasing the light transmission loss in an optical waveguide and to provide its manufacturing method. SOLUTION: The waveguide type optical control device is provided with at least an optical waveguide made of a ferroelectric body having an electrooptic effect and a control electrode provided in contact with the optical waveguide. The control electrode is constructed by stacking an upper conductive layer having an extinction coefficient of <2000 and a light-transmitting lower conductive layer which does not form an electric barrier on the interface with the ferroelectric optical waveguide. The method for manufacturing the waveguide type optical control device forms the upper and lower conductive layers by sputtering using a target having >=90% density.