Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
102 words
A method for filling a VLSI high aspect ratio recess in an interconnection structure defined in a dielectric layer disposed on one main planar surface of a substrate with a metal comprising the steps of: (a) providing a low melting point alloy of a metal and an alloying element; (b) depositing said alloy into the recess of the interconnection structure at a deposition temperature which is below the alloy melting point; (c) purifying said alloy by diffusing the alloying element to a surface layer formed on said dielectric layer and removing said surface layer, thereby leaving the metal in the interconnection structure.
Claim 2
Dependent Claim
15 words
The method of claim 1, wherein said alloy has a melting point below about 600°C.
Claim 3
Dependent Claim
28 words
The method of claim 1 or 2, wherein said metal is a low resistivity metal comprising a metal selected from the group consisting of gold, silver and copper.
Claim 4
Independent Claim
38 words
The method of any one of the preceding claims, wherein said alloying element comprises an element selected from the group consisting of silicon, germanium, lead, aluminum, calcium, antimony, cerium, europium, lanthanum, lithium, magnesium, barium, selenium, strontium and tellurium.
Claim 5
Independent Claim
20 words
The method of any one of the preceding claims, wherein said depositing step comprises depositing said alloy by bias sputtering.
Claim 6
Independent Claim
17 words
The method of any one of the preceding claims, wherein said deposition temperature is below about 400°C.
Claim 7
Independent Claim
35 words
The method of any one of the preceding claims, wherein said purifying step includes oxidizing the element thereby diffusing the element to a surface of the surface layer in the form of a surface oxide.
Claim 8
Dependent Claim
26 words
The method of claim 7, wherein said purifying step includes chemical etching or mechanical polishing the surface oxide thereby removing the alloying element from the structure.
Claim 9
Independent Claim
51 words
The method of any one of the preceding claims 1 to 6, wherein said purifying step includes continually exposing the structure to plasma etching or reactive ion etching thereby simultaneously segregating the alloying element to a surface of said surface layer and removing the segregated alloying element from the surface layer.
Claim 10
Dependent Claim
18 words
The method of claim 8 or 9, further including the step of planarizing the surface of said structure.
Claim 11
Dependent Claim
21 words
The method of claim 10, wherein said planarizing step comprises removing excess material on the dielectric layer by chemical mechanical polishing.
Claim 12
Dependent Claim
47 words
The method of claim 1, wherein said purifying step comprises the steps of: (a) planarizing said dielectric layer; (b) depositing a sink layer onto the planarized dielectric layer; (c) annealing the structure thereby diffusing the alloying element into the sink layer; and (d) removing the sink layer.
Claim 13
Independent Claim
70 words
A method for purifying an alloy of a metal and an alloy element deposited in an interconnection structure defined in a dielectric layer disposed on one main planar surface of a substrate comprising the steps of: (a) planarizing the dielectric layer; (b) depositing a sink layer onto the planarized dielectric layer; (c) annealing the structure thereby diffusing the alloy element into the sink layer; and (d) removing the sink layer.
Claim 14
Dependent Claim
17 words
The method of claim 12 or 13, wherein the dielectric layer is planarized by chemical mechanical polishing.
Claim 15
Independent Claim
25 words
The method of any one of the preceding claims 12 to 14, wherein said sink layer is deposited by evaporation, sputtering or chemical vapor deposition.
Claim 16
Independent Claim
23 words
The method of any one of the preceding claims 12 to 15, wherein said structure is annealed at a temperature below about 400°C.
Claim 17
Independent Claim
20 words
The method of any one of the preceding claims 12 to 16, wherein the sink layer is removed by chemical-mechanical-polishing.
Claim 18
Independent Claim
29 words
The method of any one of the preceding claims 12 to 17, wherein the sink layer comprises a metal selected from the group consisting of gold, silver and copper.