Pressure sensor having a bossed diaphragm
AssigneeHoneywell International Inc.
InventorsCarl Stewart, Richard Davis, Gilberto Morales
Life of this patent
Estimating the term…
Abstract
A method includes forming a mask that defines a masked area and an unmasked area on a front side of a substrate, and implanting a buried layer corresponding to the unmasked area on the front side of the substrate. The method also includes forming an epitaxial layer having a back side on the front side of the substrate and on a front side of the buried layer, and creating an opening into a back side of the substrate up to a back side of the epitaxial layer and a back side of the one or portions of the buried layer.
Claims19
A method comprising:
- forming a mask on a front side of a substrate, wherein the mask defines a masked area and an unmasked area;
- implanting a buried layer corresponding to the unmasked area on the front side of the substrate;
- forming an epitaxial layer on the front side of the substrate and on a front side of the buried layer, wherein the epitaxial layer has a back side;
- and
- creating an opening into a back side of the substrate up to a back side of the epitaxial layer and a back side of the one or portions of the buried layer, wherein creating the opening forms a diaphragm that includes a portion of the silicon epitaxial layer and has a perimeter defined by one or more portions of the buried layer, and the diaphragm carries a boss formed by a portion of the buried layer.
A method comprising:
- forming a mask on a front side of a substrate, wherein the mask defines a masked area and an unmasked area;
- implanting a buried layer corresponding to the unmasked area on the front side of the substrate;
- forming an epitaxial layer on the front side of the substrate and on a front side of the buried layer, wherein the epitaxial layer has a back side;
- creating an opening into a back side of the substrate up to a back side of the epitaxial layer and a back side of the one or portions of the buried layer;
- and
- heating the substrate to diffuse the buried layer in the substrate, wherein edges and corners of the buried layer are rounded or smoothed in response to the heating.
A method for making a pressure sensor system comprising:
- implanting a patterned buried layer, based on a masking, at a front side of a silicon substrate;
- heating the substrate to diffuse the buried layer in the substrate to round or smooth edges and corners of the buried layer;
- forming a silicon epitaxial layer having a back side on the front side of the silicon substrate and on a front side of the buried layer;
- and
- creating an opening, as defined by masking, into a back side of the substrate up to a back side of the epitaxial layer and a back side of the one or portions of the buried layer.
Dependencies are inferred from the claim text.