US 6,615,615 B2 · GePSG core for a planar lightwave circuit

Abstract

A method of depositing a core layer for an optical waveguide structure of a planar lightwave circuit. A GePSG core for an optical waveguide structure of a planar lightwave circuit is fabricated such that the optical core comprises doped silica glass, wherein the dopant includes Ge and P. In depositing a core layer from which the optical core is formed, two separate doping gasses (e.g., GeH4 and PH3) are added during the PECVD process to make Ge and P doped silica glass (GePSG). The ratio of the Ge dopant and the P dopant is configured to maintain a constant refractive index within the core layer across an anneal temperature range and to reduce a formation of bubbles within the core layer. The ratio of the Ge dopant and the P dopant is also configured to reduce refractive index birefringence within the core layer across an anneal temperature range.

Claims17

Dependent claims

A method of depositing a core layer for an optical waveguide structure of a planar lightwave circuit, the method comprising the steps of:

a) providing a flow rate for a Ge dopant for a SiO2 core layer deposition;
b) providing a flow rate for a P dopant for the core layer deposition;
and
c) controlling the flow rate for the Ge dopant and the flow rate for the P dopant to form the core layer, thereby increasing refractive index stability of the core layer across an anneal temperature range, and wherein the controlling of the flow rate for the Ge dopant and the flow rate for the P dopant is configured to reduce a formation of bubbles within the core layer.

1 more element

Dependencies are inferred from the claim text.

GePSG core for a planar lightwave circuit

Life of this patent

GePSG core for a planar lightwave circuit

Life of this patent

Abstract

Claims17