Patent ID: 8731344
Filing Date: 2014-05-20
Classification: G02F

Abstract:
1. A method for manufacturing a semiconductor optical modulator, the method comprising the steps of: forming a p-type semiconductor layer on a main surface of a p-type semiconductor substrate; forming a pair of stripe-shaped masks on the p-type semiconductor layer, the stripe-shaped masks extending in a first direction along the main surface of the p-type semiconductor substrate and being spaced apart from each other; simultaneously forming a hole extending in the first direction and a pair of stripe structures extending in the first direction by etching the p-type semiconductor layer through the stripe-shaped masks, the pair of stripe structures defining the hole and protruding in a direction crossing the main surface of the p-type semiconductor substrate; after removing the stripe-shaped masks, forming a buried layer in the hole; forming a core layer on the buried layer and the stripe structures, the core layer being made of a semiconductor material having a higher refractive index than the buried layer; and forming an upper cladding layer on the core layer, the upper cladding layer being made of an n-type semiconductor material having a lower refractive index than the core layer, wherein the buried layer is made of a semiconductor material with a lower optical absorption loss than that of the p-type semiconductor layer.