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US 8,298,751 B2Granted
Alkaline rinse agents for use in lithographic patterning
AssigneeInternational Business Machines Corporation
InventorsWilliam D. Hinsberg, Gregory Michael Wallraff
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Abstract
Lithographic patterning methods involve the formation of a (one or more) metal oxide capping layer, which is rinsed with an aqueous alkaline solution as part of the method. The rinse solution does not damage the capping layer, but rather allows for lithographic processing without thinning the capping layer or introducing defects into it. Ammoniated water is a preferred rinse solution, which advantageously leaves behind no nonvolatile residue.
Claims27
A method of treating a metal oxide film of a metal gate device, the method comprising:
- following at least one process step to form the film, rinsing at least a portion of the film with alkaline water (having a basic compound therein) to remove residue, while dissolving a limited amount of said portion of the film such that the average thickness of said portion of the film is reduced by less than 1 angstrom, and wherein following the rinsing step:
- i) the alkaline water, including its basic compound, evaporates, thereby leaving no residue, wherein the alkaline water does not include nonvolatile solutes, and
- ii) said portion of the film is not rinsed in a non-alkaline aqueous solution, wherein the metal oxide includes an oxide selected from the group consisting of magnesium, barium, scandium, cerium, samarium, erbium, terbium, neodymium, lanthanum, and gallium oxides.
A method of treating a metal oxide film of a metal gate device, the method comprising:
- following at least one process step to form the film, rinsing at least a portion of the film with alkaline water (having a basic compound therein) to remove residue, while dissolving less than 50% of the mass of said portion of the film, and wherein following the rinsing step:
- i) the alkaline water, including its basic compound, evaporates, thereby leaving no residue, wherein the alkaline water does not include nonvolatile solutes, and
- ii) said portion of the film is not rinsed in a non-alkaline aqueous solution, wherein the metal oxide includes an oxide selected from the group consisting of magnesium, barium, scandium, cerium, samarium, erbium, terbium, neodymium, lanthanum, and gallium oxides.
A method, comprising:
- (a) forming at least one semiconducting region that resides over a substrate;
- (b) forming a dielectric region on said at least one semiconducting region;
- (c) forming an inorganic capping layer on the dielectric region;
- (d) applying a photoresist layer over the capping layer;
- (e) exposing a portion of the photoresist layer to radiation to form an exposed photoresist layer;
- (f) optionally applying a post-exposure bake to the exposed photoresist layer;
- (g) developing the exposed photoresist layer to remove a portion of it, thereby revealing a first portion of the capping layer;
- (h) rinsing the developed photoresist layer and the first portion of the capping layer with alkaline water (having a basic compound therein) to remove any residue, while dissolving a limited amount of the first portion of the capping layer such that the average thickness of the first portion of the capping layer is reduced by less than 1 angstrom;
- (i) etching away the first portion of the capping layer;
- (j) applying a strip etch to remove remaining photoresist, thereby revealing a second portion of the capping layer that had been in contact with photoresist;
- and
- (k) rinsing the second portion of the capping layer with alkaline water (having a basic compound therein) to remove any residue, while dissolving a limited amount of the second portion of the capping layer such that the average thickness of the second portion of the capping layer is reduced by less than 1 angstrom;
- and wherein following the rinsing of step (k):
- (1) the alkaline water, including its basic compound, evaporates, thereby leaving no residue, wherein the alkaline water does not include nonvolatile solutes, is and
- (m) the second portion of the capping layer is not rinsed in a non-alkaline aqueous solution.
12 more elements
Dependencies are inferred from the claim text.