METHODS AND COMPOSITIONS FOR PROCESSING DIELECTRIC SUBSTRATE
Described are materials and methods for processing (polishing or planarizing) a substrate that contains pattern dielectric material using a polishing composition (aka “slurry”) and an abrasive pad, e.g., CMP processing.
1 . A method of polishing a dielectric-containing surface of a substrate, the method comprising:
providing a substrate comprising a surface that includes dielectric material,
providing a polishing pad,
providing a chemical-mechanical polishing composition comprising:
an aqueous medium,
abrasive particles dispersed in the aqueous medium, and
removal rate accelerator having the formula:
wherein R is selected from: straight or branched alkyl, aryl, substituted aryl, alkoxy, straight or branched halogen-substituted alkyl, halogen-substituted aryl, and halogen-substituted alkoxy,
the slurry having a pH of below about 7,
contacting the substrate with the polishing pad and the chemical-mechanical polishing composition; and
moving the polishing pad and the chemical-mechanical polishing composition relative to the substrate to abrade at least a portion of the dielectric layer on a surface of the substrate to polish the substrate.
2 . The method of claim 1 wherein the abrasive particles comprise ceria, zirconia, or a mixture thereof.
3 . The method of claim 1 , wherein particle is zirconia and the slurry pH is about 3.5 to about 6.5.
4 . The method of claim 3 , wherein the zirconia comprises metal-doped zirconia, non-metal-doped zirconia, or a combination thereof.
5 . The method of claim 1 wherein R is selected from methyl, phenyl, 2-hydroxyphenyl, methoxy ethoxy, or butoxy.
6 . The method of claim 1 wherein the substrate comprises a surface that includes pattern dielectric material comprising raised areas of the dielectric material and trench areas of the dielectric material, a difference between a height of the raised areas and a height of the trench areas being step height.
7 . The method of claim 1 wherein the removal rate accelerator is selected from the group consisting of acetohydroxamic acid, benzhydroxamic acid, salicylhydroxamic acid, N-hydroxyurethane, N-boc hydroxylamine and combinations thereof.
8 . The method of claim 1 wherein the composition further comprises picolinic acid.
9 . The method of claim 8 wherein the picolinic acid is in an amount in a range from 5 to 80 weight percent based on the weight of the removal rate accelerator.
10 . The method of claim 1 wherein the removal rate accelerator is salicylhydroxamic acid.
11 . The method of claim 1 wherein removal rate accelerator is present in the polishing composition at a concentration of about 5 to about 3,000 parts per million.
12 . The method of claim 1 wherein the pattern dielectric consists of dielectric material selected from silicon oxide, tetraethoxysilane, phosphosilicate glass, or borophosphosilicate glass.
13 . A chemical-mechanical polishing composition useful for polishing a dielectric-containing substrate, the composition comprising:
aqueous medium,
abrasive particles dispersed in the aqueous medium, and
removal rate accelerator having the formula:
wherein R is selected from; a straight or branched alkyl, aryl, substituted aryl, alkoxy, straight or branched halogen-substituted alkyl, halogen-substituted aryl, and halogen-substituted alkoxy,
and the slurry has a pH of below about 7.
14 . The composition of claim 13 wherein R is methyl, phenyl, 2-hydroxyphenyl, methoxy ethoxy, or butoxy.
15 . The composition of claim 13 wherein the removal rate accelerator is selected from the group consisting of acetohydroxamic acid, benzhydroxamic acid, salicylhydroxamic acid, N-hydroxyurethane, and N-boc hydroxylamine, and combinations thereof.
16 . The composition of claim 13 further comprising picolinic acid.
17 . The composition of claim 16 wherein the picolinic acid is in an amount in a range from 5 to 80 weight percent based on the weight of the removal rate accelerator.
18 . The composition of claim 13 wherein the removal rate accelerator is salicylhydroxamic acid.
19 . The composition of claim 13 wherein removal rate accelerator is present in the polishing composition at a concentration of about 5 to about 3,000 parts per million, based upon the weight of the composition.
20 . The composition of claim 13 wherein the abrasive particles comprise ceria, zirconia, or a mixture thereof.
21 . The composition of claim 20 wherein the abrasive particles are wet-process ceria particles, calcined ceria particles, metal-doped ceria particles, zirconia particles, metal-doped zirconia particles, or a combination thereof.
22 . The composition of claim 21 wherein the abrasive particles are wet-process ceria particles having a median particle size of about 40 to about 100 nanometers, are present in the polishing composition at a concentration of about 0.005 weight percent to about 2 weight percent, and have a particle size distribution of at least about 300 nanometer.
23 . The composition of claim 19 wherein the abrasive particles are present in the polishing composition at a concentration of about 0.1 weight percent to about 15 weight percent.
24 . The composition of claim 13 wherein the pH of the polishing composition is about 1 to about 6.
25 . The composition of claim 13 further comprising not greater than 0.001 weight percent of a metal passivating agent.