Title:
PRODUCTION OF OPTICAL DIRECTIONAL COUPLER OF TI-DIFFUSED WAVEGUIDE
Document Type and Number:
Japanese Patent JPH0232305
Kind Code:
A
Abstract:
PURPOSE:To obtain the optical directional coupler for which a crystal cut out in parallel with the optical axis is used by diffusing Mg ions into a Ti diffused layer and using the Ti diffused layer as a channel waveguide. CONSTITUTION:A Ti film of about 400-900Angstrom is formed over the entire surface of a Y-cut LiNbO3 substrate 11 and after the thermal diffusion of Ti is executed in the atm. contg. steam for about 8 hours at about 1,000 deg.C; thereafter, a thin MgO film is formed to about 900Angstrom and is patterned. The intervals of the thin MgO film patterns are required to be widened by about several 10% from the desired Ti waveguide width by taking the influence of the transverse diffusion of the Mg ions into consideration. The MgO pattern of the points where the gap part of the Ti-diffused optical directional coupler are formed has about 5mum width in this way. The Mg ions are diffused for a few hours at about 900 deg.C in gaseous oxygen. The optical directional coupler of the Ti diffused waveguide for which the crystal cut out in parallel with the optical axis is used is obtd. in this way.
Inventors:
IWASAKI MASAAKI
Application Number:
JP18208088A
Publication Date:
February 02, 1990
Filing Date:
July 21, 1988
Export Citation:
Assignee:
NEC CORP
International Classes:
G02B6/122; G02B6/12; G02B6/13; (IPC1-7): G02B6/12
Attorney, Agent or Firm:
Ozeki Shinsuke
Next Patent: JPH0232306