Frances Ann Williams

US Patent:

7784346, Aug 31, 2010

Filed:

Aug 8, 2005

Appl. No.:

11/199102

Inventors:

Frances R. Williams - Norfolk VA, US
Gary S. May - Atlanta GA, US

Assignee:

Georgia Tech Research Corporation - Atlanta GA

International Classification:

G01N 29/024

US Classification:

73597, 73598, 73632

Abstract:

Disclosed are micromachined acoustic sensors for monitoring electrochemical deposition, methods for fabricating such sensors, and methods for in-situ monitoring of electrochemical deposition processes using such sensors. An exemplary acoustic sensor includes a deformable silicon membrane, an encapsulated piezoelectric layer formed on the silicon membrane, and surface electrodes formed on the piezoelectric layer. The sensor and a loudspeaker may be used to calibrate an electrochemical deposition process. The acoustic response of the sensor is monitored over time with respect to plating thickness during electroplating of a sample to generate a predictive model defining the plating process. The predictive model may be used to monitor the plating thickness of other samples in real time.