STRENGTHENED GLASS AND METHODS FOR MAKING UTILIZING ELECTRIC FIELD ASSIST

摘要

Chemically strengthened glass with high surface compression, deeper case depth, shorter processing time and a reduced induced curvature relative to that obtained in a traditional immersion method and a method for making utilizing an electric filed assist are provided. The method includes providing a substrate, characterized by having a glass chemical structure including host alkali ions having an average ionic radius situated in the glass chemical structure. The method also includes exposing the substrate to the exchange medium; and conducting ion exchange to produce a strengthened substrate while exposing the substrate to the exchange medium and applying an electric field in a plurality of cycles across the surfaces of the substrate.

主权项

1. A method for making comprising:
providing a substrate having a first surface and a second surface,
wherein the substrate is characterized by having a glass chemical structure including host alkali ions situated in the structure and having an average ionic radius; providing an exchange medium including invading alkali ions having an average ionic radius that is larger than an average ionic radius of the host alkali ions; exposing the substrate to the exchange medium; and conducting ion exchange to produce a strengthened substrate while exposing the substrate to the exchange medium and applying an electric field across the surfaces of the substrate,
wherein applying the electric field includes reversing a polarity of the electric field through a plurality of cycles,wherein the strengthened substrate has a first compressive stress layer extending from the first surface into the substrate and second compressive stress layer extending from the second surface into the substrate,wherein the strengthened substrate has a balanced compressive stress profile based on
a first plot of first compressive stress amounts at first depths from the first surface within the first compressive stress layer,a second plot of second compressive stress amounts at second depths from the second surface within the second compressive stress layer, andat a corresponding first depth and second depth from the respective surfaces, a magnitude of a difference between a first compressive stress amount at the first depth and a second compressive stress amount at the second depth, is less than 500 MPa.