| 摘要 |
<p>PURPOSE:To faithfully transfer wiring circuits of a branch shape and to prevent the leakage of light to parts exclusive of a prescribed waveguide by exchanging plural sheets of masks so as to avoid the interference of light, successively executing exposing, then developing and processing. CONSTITUTION:A substrate 1 is formed by using n type InP and an InGaAsP layer is grown thereon, then an InP layer 3 is grown as a clad layer thereon. An InGaAsP layer 4 is grown as a cap layer thereon. Zn is diffused to form a shape 5 and after this part is made into a p type, a negative resist is applied thereon and is exposed by using the 1st mask 6. The resist is then exposed by using the 2nd mask 7 without being developed and is thereafter subjected to the development, by which the Y-shaped photomask having no dulling is formed in the branch part 8. The faithful transfer of the desired shape is possible in this way and the optical switch which suppresses the leakage of the light to the parts exclusive of the prescribed waveguide is obtd.</p> |
