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US 11,111,415 B2Granted
Chemical mechanical planarization of films comprising elemental silicon
AssigneeVersum Materials US, LLC
InventorsJames Matthew Henry, Hongjun Zhou, Krishna P. Murella, Dnyanesh Chandrakant Tamboli, Joseph Rose
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Abstract
Chemical Mechanical Planarization (CMP) polishing compositions comprising abrasive particles and additives to boost removal rates of films comprising elemental silicon such as poly-silicon and Silicon-Germanium.
Claims13
A polishing method for chemical mechanical planarization of a semiconductor substrate comprising at least one surface containing elemental silicon, comprising the steps of:
- contacting the at least one surface containing elemental silicon with a polishing pad;
- delivering a polishing composition to the at least one surface containing elemental silicon;
- wherein the polishing composition consisting essentially of:
- abrasive particles ranging from 0.01 wt. % to 15 wt. %;
- a compound to enhance removal rate of films comprising elemental silicon ranging from 0.001 wt. % to 0.5 wt. %;
- liquid carrier;
- and optionally an additive selected from the group consisting of (i) a polyacrylic acid or its salts with molecular weight ranging between 500 and 100,000;
- (ii) an additive having a functional group selected from the group consisting of organic carboxylic acids and salts thereof, amino acids and salts thereof, aminocarboxylic acids and salts thereof, N-acylamino acids and salts thereof, organic sulfonic acids and salts thereof, organic phosphonic acids and salts thereof, polymeric carboxylic acids and salts thereof, polymeric sulfonic acids and salts thereof, polymeric phosphonic acids and salts thereof, arylamines, aminoalcohols, aliphatic amines, heterocyclic amines, hydroxamic acids, substituted phenols, sulfonamides, thiols, polyols having hydroxyl groups, and combinations thereof;
- and combinations of (i) and (ii);
- a pH adjusting agent;
- a surfactant selected from the group consisting of a) non-ionic surface wetting agents;
- b) anionic surface wetting agents;
- c) cationic surface wetting agents;
- d) ampholytic surface wetting agents;
- and mixtures thereof;
- and a biological growth inhibitors or preservatives to prevent bacterial and fungal growth during storage;
- wherein pH of the polishing composition is between 2 and 12;
- wherein the abrasive particles are selected from the group consisting of fumed silica, colloidal silica, fumed alumina, colloidal alumina, cerium oxide, ceria-silica composite particles, titanium dioxide, zirconium oxide, polystyrene, polymethyl methacrylate, mica, hydrated aluminum silicate, and combinations thereof;
- and wherein the compound to enhance removal rate of films comprising elemental silicon is selected from the group consisting of isothiazolinone and derivatives, thiazolinone and derivatives, imidazolidine and derivatives, pyrozolidine and derivatives, imidazole and derivatives, pyrazole and derivatives, thiazole and derivatives, isothiazole, and derivatives, thiazolidine and derivatives, isothiazolidine and derivatives, dithiolane and derivatives, triazole and derivatives, tetrazole and derivatives, thiadiazole and derivatives, acetone, benzophenone, acetophenone, acetylacetone, butanol, 3-hydroxybutanal, p-nitrobenzenzaaldehyde, cinnamaldehyde, vanillin, and combinations thereof;
- and polishing the at least one surface containing elemental silicon with the polishing composition.
17 more elements
A method for selectively increasing or decreasing the removal rate of elemental silicon in relation to a compound of silicon during chemical mechanical planarization of a semiconductor substrate, comprising the steps of:
- a) contacting, with a polishing pad, a semiconductor substrate comprising a first surface containing elemental silicon and a second surface comprising a compound of silicon;
- b) providing a polishing composition comprising abrasive particles, a liquid carrier and a first additive selected from the group consisting of isothiazolinone and derivatives, thiazolinone and derivatives, imidazolidine and derivatives, pyrozolidine and derivatives, imidazole and derivatives, pyrazole and derivatives, thiazole and derivatives, isothiazole and derivatives, thiazolidine and derivatives, isothiazolidine and derivatives, dithiolane and derivatives, triazole and derivatives, tetrazole and derivatives, thiadiazole and derivatives, acetone, benzophenone, acetophenone, acetylacetone, butanol, 3-hydroxybutanal, p-nitrobenzenzaaldehyde, cinnamaldehyde, vanillin, and combinations thereof, wherein the first additive comprises a first additive concentration and a second additive selected from the group consisting of (i) a polyacrylic acid or its salts with molecular weight ranging between 500 and 100,000;
- (ii) an additive having a functional group selected from the group consisting of organic carboxylic acids and salts thereof, amino acids and salts thereof, amidocarboxylic acids and salts thereof, N-acylamino acids and salts thereof, organic sulfonic acids and salts thereof;
- organic phosphonic acids and salts thereof;
- polymeric carboxylic acids and salts thereof;
- polymeric sulfonic acids and salts thereof;
- polymeric phosphonic acids and salts thereof;
- arylamines, aminoalcohols, aliphatic amines, heterocyclic amines, hydroxamic acids, substituted phenols, sulfonamides, thiols, polyols having hydroxyl groups, and combinations thereof;
- and combinations of (i) and (ii);
- c) contacting the polishing composition with the first and second surfaces and the polishing pad;
- d) polishing the first and second surfaces with the polishing pad and the polishing composition to produce a first removal rate of the first surface and a second removal rate of the second surface, wherein a removal rate selectivity is defined by the ratio of the first removal rate to the second removal rate;
- e) tuning the removal rate selectivity, wherein the tuning is accomplished by varying the first additive concentration and the second additive concentration.
9 more elements
A method comprising:
- a) preparing a polishing composition comprising abrasive particles, a liquid carrier and a first additive selected from the group consisting of isothiazolinone and derivatives, thiazolinone and derivatives, imidazolidine and derivatives, pyrozolidine and derivatives, imidazole and derivatives, pyrazole and derivatives, thiazole and derivatives, isothiazole and derivatives, thiazolidine and derivatives, isothiazolidine and derivatives, dithiolane and derivatives, triazole and derivatives, tetrazole and derivatives, thiadiazole and derivatives, acetone, benzophenone, acetophenone, acetylacetone, butanol, 3-hydroxybutanal, p-nitrobenzenzaaldehyde, cinnamaldehyde, vanillin, and combinations thereof, the first additive having a first additive concentration representing a weight percentage of the polishing compound provided by the first additive;
- b) placing the polishing compound in contact with at least one selected from the group of a polishing pad and a semiconductor substrate having a first film comprising elemental silicon and a second film comprising a compound of silicon;
- c) polishing the first and second films with the polishing pad and the polishing composition resulting in a first removal rate of the first film and a second removal rate of the second film, wherein the first removal rate is different from the second removal rate;
- d) prior to performing the step a), selecting the first additive and the first additive concentration to produce a desired removal rate selectivity, the removal rate selectivity being a ratio of the first removal rate to the second removal rate;
- and
- e) after performing steps (a) through (d) at least once, changing the first additive concentration selected in step (d) to more closely produce the desired removal rate selectivity.
3 more elements
Dependencies are inferred from the claim text.