Eddy current system for in-situ profile measurement
AssigneeApplied Materials, Inc.
InventorsG. Laurie Miller, Boguslaw A. Swedek, Manoocher Birang
Life of this patent
Estimating the term…
Abstract
An eddy current monitoring system may include an elongated core. One or more coils may be coupled with the elongated core for producing an oscillating magnetic field that may couple with one or more conductive regions on a wafer. The core may be translated relative to the wafer to provide improved resolution while maintaining sufficient signal strength. An eddy current monitoring system may include a DC-coupled marginal oscillator for producing an oscillating magnetic field at a resonant frequency, where the resonant frequency may change as a result of changes to one or more conductive regions. Eddy current monitoring systems may be used to enable real-time profile control.
Claims28
An apparatus for chemical mechanical polishing, comprising:
- a platen to support a polishing surface;
- and
- an eddy current monitoring system to generate an eddy current signal, the eddy current monitoring system comprising an elongated core positioned at least partially in the platen, the elongated core including one or more protrusions and having a length and a width, the length being parallel to the polishing surface and longer than the width, at least one of the one or more protrusions and the core having a common length along an axis of the length of the core.
An eddy current sensing system, comprising:
- an elongated core including a back portion and one or more protrusions extending away from the back portion along a first axis, the elongated core having a length and a width, the length being orthogonal to the first axis and longer than the width, at least one of the one or more protrusions and the core having a common length alone an axis of the length of the core;
- a housing having mounting features shaped and configured to position the elongated core in a recess of a platen;
- a coil wound around a portion of the elongated core;
- a drive system to generate a current in the coil;
- and
- a sense system to derive a characteristic of a conductive region based on eddy currents generated in the conductive region.
An apparatus for chemical mechanical polishing, comprising:
- a platen having a top surface to support a polishing surface;
- and
- an eddy current monitoring system to generate an eddy current signal, the eddy current monitoring system including an elongated core positioned at least partially in the platen, the elongated core having a plurality of prongs extending in parallel along a first axis parallel to the top surface and spaced apart from each other along a second axis parallel to the top surface and perpendicular to the first axis, the core having a length along the first axis and a width along the second axis, the length being longer than the width.
Dependencies are inferred from the claim text.