Control of ion angular distribution function at wafer surface
First Claim
1. A method of controlling the angular distribution of ions incident onto the surface of a semiconductor wafer on an RF biased substrate holder during plasma processing, comprising:
- applying opposite and alternating potentials across pairs of conductors below the wafer supporting surface of a substrate holder in a plasma processing apparatus, wherein the pairs of conductors lie in a plane parallel to the wafer supporting surface;
creating with the applied opposite and alternating potentials, at one or more points on the wafer supporting surface, an electric field directed parallel to the surface of a semiconductor wafer supported on the substrate holder; and
impinging ions from a plasma across a plasma sheath and through the created electric field onto the surface of the semiconductor wafer while controlling the applied opposite and alternating potentials to affect the angular distribution of ions impinging onto the semiconductor wafer over the one or more points on the wafer supporting surface.
1 Assignment
0 Petitions
Accused Products
Abstract
A manufacturing method and apparatus for IC fabrication controls the ion angular distribution at the surface of a wafer with electrodes in a wafer support that produce electric fields parallel to the wafer surface without disturbing plasma parameters beyond the wafer surface. The ion angular distribution function (IADF) at the wafer surface is controlled for better feature coverage or etching. Grid structure is built into the substrate holder within the coating at the top of the holder. The grid components are electrically biased to provide electric fields that combine with the sheath field to distribute the ion incidence angles from the plasma sheath onto the wafer. The grid can be dynamically biased or phased to control uniformity of the effects.
29 Citations
20 Claims
-
1. A method of controlling the angular distribution of ions incident onto the surface of a semiconductor wafer on an RF biased substrate holder during plasma processing, comprising:
-
applying opposite and alternating potentials across pairs of conductors below the wafer supporting surface of a substrate holder in a plasma processing apparatus, wherein the pairs of conductors lie in a plane parallel to the wafer supporting surface; creating with the applied opposite and alternating potentials, at one or more points on the wafer supporting surface, an electric field directed parallel to the surface of a semiconductor wafer supported on the substrate holder; and impinging ions from a plasma across a plasma sheath and through the created electric field onto the surface of the semiconductor wafer while controlling the applied opposite and alternating potentials to affect the angular distribution of ions impinging onto the semiconductor wafer over the one or more points on the wafer supporting surface. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
-
Specification