Manufacturing method of silicon-based optical waveguide device

Abstract

The invention discloses a manufacturing method of a silicon-based optical waveguide device. The method comprises the steps: forming an SOI substrate, wherein the SOI substrate includes a silicon substrate, a buried oxide layer and a top silicon layer which are sequentially stacked from bottom to top; etching the top silicon layer to form a waveguide structure and a first groove; forming an upper cladding on an upper surface of the waveguide structure and the upper surface of the buried oxide layer, wherein a material of the upper cladding is the same as that of the buried oxide layer; etchingthe upper cladding and the buried oxide layer to form a second groove; and etching the silicon substrate to form a third groove, wherein a depth of the third groove is less than a thickness of the silicon substrate, and a horizontal projection of the third groove is superposed with the horizontal projection of the second groove. According to the manufacturing method of the silicon-based optical waveguide device provided by the invention, when a deep groove structure for end surface coupling is formed, an etching process only needs to be switched once so that an etching menu is simplified, andetching difficulty and a requirement to the thickness of photoresist are reduced.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a method for manufacturing a silicon-based optical waveguide device. Background technique [0002] With the continuous development of silicon-based photonic chip integration technology, the use of photonic chips to realize short-distance optical communication between chips or within chips is getting closer and closer to reality. Silicon on Insulator (SOI, Silicon On Insulator) has very good optical characteristics, and because silicon has a very large refractive index difference with silicon dioxide or air, silicon-based optical waveguides have a very strong ability to confine light fields, so silicon Basic optical waveguides can be fabricated to very small sizes. While the very small size of the silicon-based optical waveguide brings high device integration, it also brings a serious problem—the coupling loss between the silicon-based optical waveguide and the optical fib...

AI Technical Summary

Problems solved by technology

While the very small size of the silicon-based optical waveguide brings high device integration, it also brings a serious problem—the coupling loss between the silicon-based optical waveguide and the optical fiber is very large. A key problem that interconnection urgently needs to solve

Images