Target for use in magnetron sputtering of nickel for forming metallization films having consistent uniformity through life
AssigneeApplied Materials, Inc.
InventorsMurali Abburi, Seshadri Ramaswami
Life of this patent
Estimating the term…
Abstract
Improved targets for use in DC magnetron sputtering of nickel or like ferromagnetic face-centered cubic (FCC) metals are included for forming metallization films having effective edge-to-edge deposition uniformity of 5% (3σ) or better. Such targets may be characterized as having: (a) a homogeneous texture mix that is at least 20% of a <200> texture content and less than 50% of a <111> texture content, (b) an initial pass-through flux factor (% PTF) of about 30% or greater; and(c) a homogeneous grain size of about 200 μm or less.
Claims19
A target certifying method for certifying lots of ferromagnetic targets for use in a DC_magnetron PVD system adapted to receive said targets for installation therein, wherein each said target of a given lot is manufactured in essentially a same manner as other members of the given lot to have a deposition-producing portion composed primarily of an electrically and magnetically conductive, to-be-deposited metal, said certifying method comprising the steps of:
- (a) selecting one or more representative samples from a given lot;
- (b) testing each selected sample target for compliance with two or more of the following characteristics:
- (b.1) an average texture mix that is at least 20% <200> texture and less than 50% <111> texture;
- (b.2) an initial pass-through flux factor (% PTF) of about 30% or greater;
- and
- (b.3) a homogeneous grain size of about 200 μm or less;
- and
- (c) certifying for commercial use each given lot whose selected samples comply with the two or more characteristics while not certifying each given lot for which a statistically significant number of the selected samples do not comply with said two or more characteristics.
A qualification method for qualifying manufacturing targets that are adapted for installation into a DC-magnetron PVD system for uniform operation over a pre-specified lifetime, wherein each said target has a deposition-producing portion composed primarily of a magnetically and electrically conductive, to-be-deposited metal, which metal has a tendency to form polycrystals of face-centered cubic structure, including <200> and <111> textured polycrystals, and said target qualification method comprises:
- (a) assuring by sampling and statistical analysis that each target has a statistically significant likelihood of having in its deposition-producing portion a texture mix that is at least 20% <200> texture and less than about 50% of the <111> texture.
Dependencies are inferred from the claim text.