MANUFACTURE OF OPTICAL DEVICE

摘要

PURPOSE:To enable the manufacture of a high-precision, small-sized and inexpensive optical device such as prism by forming, on a transparent crystal substrate sliced into a wafer in a predetermined crystal plane, an etching mask layer having window sections disposed therein, performing an anisotropical etching to form hole sections having a sloped surface, and thereafter dicing the substrate. CONSTITUTION:A transparent crystal substrate 1 sliced into a wafer in a predetermined crystal plane is prepared, an etching mask layer 5 is formed thereon in which window sections 6 for etching are regularly disposed, and an anisotropical etching is performed, thereby forming a hole section 7 having a sloped surface 8 under each window section 6 for etching. Thereafter, a crystal substrate 1 is diced, providing many optical devices 10 having the sloped surface 8 as one end face. For instance, in the predetermined positions on both surfaces 2, 3 of a wafer-shaped crystal substrate 1 composed of a single crystal of GaP which was sliced in a plane inclined about 5.3 deg. from the plane (001) to the <110> direction, reflective films 4, 4 are formed. Then, an etching mask layer 5 is formed, an anisotropical etching is performed to form hole sections 7, and thereafter dicing the substrate, thereby obtaining prisms 10 having a trpezoidal cross-sectional shape.