Patent ID: 7941023
Filing Date: 2011-05-10
Classification: G02B,G02F

Abstract:
1. A method of forming a low loss SOI-based optical waveguiding structure, the method comprising the steps of: a) providing an SOI structure including a silicon substrate, an insulating layer disposed over the silicon substrate and a relatively thin silicon surface layer disposed over the insulating layer; b) forming a relatively thick oxide layer over the relatively thin silicon surface layer; c) depositing an oxide-resistant layer over the relatively thick oxide layer formed in step b); d) patterning the oxide-resistant layer to define a portion to be used to form the optical waveguiding structure; e) removing the oxide resistant layer outside of the defined portion patterned in step d) to expose the underlying relatively thick oxide layer; f) oxidizing the structure of step e), consuming a portion of the relatively thin silicon layer with preferential growth of the relatively thick oxide layer beyond the defined waveguiding portion to the structure, transforming the relatively thin silicon surface layer in the waveguiding portion to exhibit a relatively rounded and smooth profile; and g) removing the remaining oxide-resistant layer and the relatively thick oxide layer to expose the relatively rounded and smooth, low loss optical waveguiding structure formed within the relatively thin silicon surface layer.