Device and method for compensating a capacitive sensor measurement for variations caused by environmental conditions in a semiconductor processing environment
OwnerDelRae H. Gardner, Andy K. Liminventors
Life of this patent
Estimating the term…
Abstract
A method of sensing proximity to a showerhead in a semiconductor-processing system is provided. The method includes measuring a parameter that varies with proximity to the showerhead, as well as with at least one external factor. The method also includes measuring a parameter that does not vary with proximity to the showerhead, but does vary with the at least one factor. A compensated proximity output is calculated based upon the measured parameters and is provided as an output.
Claims17
A method of sensing proximity to a showerhead in a semiconductor-processing system, the method comprising:
- providing a first sensing capacitive plate that is operably supported by a substrate support pedestal;
- providing a second sensing capacitive plate that forms a sensing capacitor with the first sensing capacitive plate, wherein the sensing capacitor has a capacitance that varies with distance between the substrate support pedestal and the showerhead and also varies with at least one external factor;
- providing first and second reference capacitive plates to form a reference capacitor having a reference capacitance that does not vary with distance between the substrate support pedestal and the showerhead, but does vary with the at least one external factor;
- measuring the capacitance of the sensing capacitor;
- measuring the capacitance of the reference capacitor;
- providing an output relative to the proximity of the showerhead based upon the capacitance of the sensing and reference capacitances.
A method of sensing proximity to a showerhead in a semiconductor-processing system, the method comprising:
- measuring a parameter that varies with proximity to the showerhead, as well as with at least one external factor;
- measuring a parameter that does not vary with proximity to the showerhead, but does vary with the at least one factor;
- calculating a compensated proximity output based upon the measured parameters;
- and
- providing the calculated proximity output.
A sensor for sensing proximity to a showerhead in a semiconductor processing system, the sensor comprising:
- a controller;
- capacitance measurement circuitry operably coupled to the controller;
- a proximity sensing capacitor operably coupled to the capacitance measurement circuitry;
- a reference capacitor operably coupled to the capacitance measurement circuitry;
- and
- wherein the controller is configured to provide a compensated proximity output based upon a sense capacitance and a reference capacitance.
Dependencies are inferred from the claim text.