Variable quadruple electromagnet array in plasma processing
First Claim
1. In a plasma processing reactor having a substrate support disposed in a plane perpendicular to a central axis of a vacuum chamber, an array of separately controllable electromagnetic coils arranged about said central axis, at least two of the coils being disposed at different radii from the central axis.
1 Assignment
0 Petitions
Accused Products
Abstract
A quadruple electromagnetic coil array coaxially arranged in a rectangular array about a chamber axis outside the sidewalls of a plasma sputter reactor, preferably in back of an RF coil within the chamber. The coil currents can be separately controlled to produce different magnetic field distributions, for example, between a sputter deposition mode in which the sputter target is powered to sputter target material onto a wafer and a sputter etch mode in which the RF coil supports the gas sputtering the wafer. The coil array may include a tubular magnetic core, particularly useful for suppressing stray fields. A water cooling coil may be wrapped around the coil array to cool all the coils. The electromagnets can be powered in different relative polarities in a multi-step process.
-
Citations
38 Claims
- 1. In a plasma processing reactor having a substrate support disposed in a plane perpendicular to a central axis of a vacuum chamber, an array of separately controllable electromagnetic coils arranged about said central axis, at least two of the coils being disposed at different radii from the central axis.
- 10. An array of electromagnetic coils fixed in an assembly and having both ends of all of said coils available on an outside of said assembly.
- 14. A quadruple array comprising four electromagnetic coils in an assembly annular about an axis in a rectangular pattern and configured for being disposed outside and around the wall of a plasma processing reactor.
-
20. A plasma processing reactor, comprising:
-
a chamber body arranged generally symmetrically about a central axis;
a support for supporting within said reactor a substrate to be plasma processed on a front face thereof; and
an array of a plurality of electromagnets wound about said chamber body at at least two radii from said central axis and at a axial distance displaced above said front face, at least some of said electromagnets being independently powerable. - View Dependent Claims (21, 22, 23, 24, 25, 26, 27)
-
-
29. An adapter and electromagnet assembly, comprising:
-
an adapter body generally arranged about a central axis and configured to be vacuum sealed to a plasma processing chamber with said central axis being perpendicular to a surface of a substrate to be processed; and
a plurality of electromagnetic coils wound on an exterior of said adapter body at at least two radii from said central axis and each having two leads accessible from an exterior of said coils. - View Dependent Claims (30, 31, 32, 33)
-
- 34. The assembly of claim 31, wherein said body comprises a helically wound rectangular member having said cooling channel formed therein.
-
34-1. A method of operating a plasma reactor including a chamber arranged around a central axis, a substrate support for supporting a substrate to be processed, and an array of a plurality of electromagnetic coils wound around said central axis in a vicinity of said chamber, said method comprising the steps of:
-
a first step including passing co-rotating currents through at least two of said coils to process said substrate; and
a second step including passing counter-rotating currents through said at least two coils to process said substrate.
-
Specification