Electrode for Use in Measuring Dielectric Properties of Parts

• US 20090091341A1
• Filed: 09/29/2008
• Published: 04/09/2009
• Est. Priority Date: 10/05/2007
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Comendant, Keith, Sato, Arthur H., Wu, Feiyang, Liu, Qing, Kim, Jaehyun
• Granted Patent: US 8,519,724 B2
• Time in Patent Office: Days
• US Class Current: 324/722
• CPC Class Codes: G01N 27/04 by investigating resistance
• CPC Class Codes: G01R 27/2623 Measuring-systems or electronic circuits G01R27/2635, G01R27/2682 take precedence
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

A plate of substantially uniform thickness is formed from an electrically conductive material. The plate has a top surface defined to support a part to be measured. The plate has a bottom surface defined to be connected to a radiofrequency (RF) transmission rod such that RF power can be transmitted through the RF transmission rod to the plate. The plate is defined to have a number of holes cut vertically through the plate at a corresponding number of locations that underlie embedded conductive material items in the part to be measured when the part is positioned on the top surface of the plate.

Claims

1. An electrode for use in measuring dielectric properties of a part, comprising:

a plate formed from an electrically conductive material, the plate having a top surface defined to support a part to be measured, the plate having a bottom surface defined to be connected to a radiofrequency (RF) transmission rod such that RF power can be transmitted through the RF transmission rod to the plate, wherein the plate is defined to have a number of holes cut vertically through the plate at a corresponding number of locations that underlie embedded conductive material items in the part to be measured when the part is positioned on the top surface of the plate.

2. An electrode for use in measuring dielectric properties of a part as recited in claim 1, wherein the plate is formed from copper metal.

3. An electrode for use in measuring dielectric properties of a part as recited in claim 1, wherein a vertical thickness of the plate from the top surface to the bottom surface is within a range extending from about 0.125 inch to about 2 inches.

4. An electrode for use in measuring dielectric properties of a part as recited in claim 1, wherein a vertical thickness of the plate from the top surface to the bottom surface is about 0.75 inch.

5. An electrode for use in measuring dielectric properties of a part as recited in claim 1, wherein the plate includes a number of alignment features defined to facilitate alignment of the part to be measured on the top surface of the plate.

6. An electrode for use in measuring dielectric properties of a part as recited in claim 1, wherein a periphery of the plate is defined to be proximate to a periphery of the part to be measured when the part to be measured is positioned on the top surface of the plate so as to be substantially centered on the top surface of the plate.

7. An electrode for use in measuring dielectric properties of a part as recited in claim 1, wherein the plate is defined to be an interchangeable component within an apparatus for measuring dielectric properties of the part.

8. A method for defining an electrode for use in measuring dielectric properties of a part, comprising:

forming a plate of electrically conductive material to have an outer perimeter defined to substantially match an outer perimeter of a part, wherein the part is a dielectric part including a number of embedded conductive material items;

identifying a location of each embedded conductive material item within the part;

projecting the identified location of each embedded conductive material item within the part upon the plate with the outer perimeters of the part and the plate substantially aligned; and

removing a portion of the plate at each embedded conductive material item location as projected upon the plate.

9. A method for defining an electrode for use in measuring dielectric properties of a part as recited in claim 8, wherein a size of each removed portion of the plate is sufficient to ensure that the plate is not located below the embedded conductive material item within the part when the part is positioned upon the plate with the outer perimeters of the part and the plate substantially aligned.

10. A method for defining an electrode for use in measuring dielectric properties of a part as recited in claim 8, wherein removing the portion of the plate at each embedded conductive material item location is performed such that the plate remains a single contiguous component.

11. A method for defining an electrode for use in measuring dielectric properties of a part as recited in claim 8, wherein the plate is formed from copper metal.

12. A method for defining an electrode for use in measuring dielectric properties of a part as recited in claim 8, wherein a vertical thickness of the plate from a top surface of the plate to a bottom surface of the plate is within a range extending from about 0.125 inch to about 2 inches.

13. A method for defining an electrode for use in measuring dielectric properties of a part as recited in claim 8, further comprising:

forming a number of alignment features within the plate to facilitate alignment of the part on a top surface of the plate.

14. A method for defining an electrode for use in measuring dielectric properties of a part as recited in claim 8, further comprising:

forming a number of fastening devices within the plate to enable securing of the plate to a support rod within an apparatus for measuring dielectric properties of the part.

15. An electrode for use in measuring dielectric properties of a ring-shaped part, wherein the ring-shaped part includes a number of embedded conductive material items circumferentially disposed within the ring-shaped part, comprising:

a plate formed from an electrically conductive material, wherein the plate includes a solid center region and a number of spokes extending radially outward from the solid center region by an extent sufficient to enable support of the ring-shaped part on a top surface of each of the number of spokes, wherein the number of spokes are defined and spaced about the solid center region such that the number of spokes support the ring-shaped part at locations between adjacent embedded conductive material items within the ring-shaped part.

16. An electrode as recited in claim 15, wherein the solid center region and each of the number of spokes are defined to have a substantially uniform vertical thickness extending from a top surface of the plate to a bottom surface of the plate.

17. An electrode as recited in claim 16, wherein the substantially uniform vertical thickness is about 0.75 inch.

18. An electrode as recited in claim 15, wherein the plate is formed from copper metal.

19. An electrode as recited in claim 15, wherein adjacent ones of the number of spokes are separated from each other by a gap within which the plate is absent.

20. An electrode as recited in claim 15, wherein a bottom surface of the solid center region of the plate includes a number of fastening devices defined to enable securing of the plate to a support rod within an apparatus for measuring dielectric properties of the part.