Patent ID: 8455289
Filing Date: 2013-06-04
Classification: B06B,G01N

Abstract:
1. A method of forming a semiconductor transducer comprising: providing semiconductor substrate having top and bottom surfaces wherein the top surface lies in a plane; growing approximately a 5.15 micrometer thick oxide layer on both the top and bottom surfaces of the semiconductor wafer using a high-pressure oxidation (HIPOX) process; wherein the 5.15 micrometer thick oxide layer is grown at a temperature in range of 900° C. to 1200° C. with an operating pressure of 10 to 20 atmospheres; forming a patterned photoresist layer on the thick oxide layer on the top surface of the semiconductor substrate; etching the thick oxide layer, exposing the top surface of the semiconductor substrate and forming a post structure on the top surface of the semiconductor substrate from the thick oxide layer, wherein the post structure having a top surface, being non-conductive, and laterally surrounding a cell region of the top surface of the substrate has no portion of the post structure lying below the plane of the top surface of the semiconductor substrate; wherein etching the thick oxide layer comprises: forming a non-conductive structure that touches the cell region of the top surface of the semiconductor substrate; and forming a conductive structure that touches the top surface of the post structure and lies directly vertically over the non-conductive structure to form a cavity that lies vertically between the non-conductive structure and the conductive structure.