Cointegration of optical waveguides, microfluidics, and electronics on sapphire substrates

摘要

A method of forming a semiconductor structure includes forming a first optical waveguide and a second optical waveguide on a sapphire substrate. The first optical waveguide and the second optical waveguide each include a core portion of gallium nitride (GaN), and a cladding layer laterally surrounding the core portion. The cladding layer includes a material having a refractive index less than a refractive index of the sapphire substrate. The method further includes etching a portion of the cladding layer to form a microfluidic channel therein and forming a capping layer on a top surface of the first optical waveguide, the second optical waveguide and the microfluidic channel.

主权项

1. A method of forming a semiconductor structure, said method comprising:
forming a first optical waveguide and a second optical waveguide on a sapphire substrate, wherein the first optical waveguide and the second optical waveguide each include a core portion of gallium nitride (GaN), and a cladding layer laterally surrounding the core portion, wherein the cladding layer includes a material having a refractive index less than a refractive index of the sapphire substrate; etching a portion of the cladding layer to form a microfluidic channel in the cladding layer; and forming a capping layer on a top surface of the first optical waveguide, the second optical waveguide and the microfluidic channel, wherein the cladding layer and the capping layer each include one of silicon oxide (SiO2) or glass, and wherein the first optical waveguide and the second optical waveguide are formed on the sapphire substrate by:
epitaxially growing a GaN layer on a seed layer located on the sapphire substrate;etching the GaN layer to form the first optical waveguide core portion and a second optical waveguide core portion on the sapphire substrate;depositing a cladding material on the sapphire substrate to backfill substantially all areas on the top surface of the sapphire substrate not occupied by the first optical waveguide core portion, the second optical waveguide core portion, and the seed layer with the cladding material; andplanarizing the cladding material to form the cladding layer, wherein a top surface of the cladding layer is coplanar with a top surface of the first optical waveguide core and a top surface of the second optical waveguide core.