Polishing composition and polishing method

A method for polishing an object to form wiring in a semiconductor device, wherein the object has a barrier layer and a conductive layer in this order on an insulating layer having a trench, and the barrier layer and the conductive layer have a portion positioned outside the trench and a portion positioned inside the trench, respectively, the method comprising:

• removing a part of the portion of the conductive layer positioned outside the trench by chemical mechanical polishing to expose an upper surface of the barrier layer, and
• removing the remaining part of the portion of the conductive layer positioned outside the trench and the portion of the barrier layer positioned outside the trench by chemical mechanical polishing to expose an upper surface of the insulating layer,
• wherein a first polishing composition is used in the chemical mechanical polishing to remove a part of the portion of the conductive layer positioned outside the trench, and a second polishing composition is used in the chemical mechanical polishing to remove the remaining part of the portion of the conductive layer positioned outside the trench and the portion of the barrier layer positioned outside the trench, and
• the first polishing composition includes a surfactant, a silicon oxide, a carboxylic acid, an anticorrosive, an oxidizing agent and water, the surfactant including at least one kind selected from the compounds represented by general formulae (1) to (7) below and salts thereof;
• in the general formula (1), R1 represents an alkyl group having 8 to 16 carbon atoms, R2 represents a hydrogen atom, a methyl group, or an ethyl group, R3 represents an alkylene group having 1 to 8 carbon atoms, —(CH2CH2O)1—, —(CH2CH(CH3)O)m—, or a combination of at least two kinds thereof, when R3 represents —(CH2CH2O)1— or —(CH2CH(CH3)O)m—, 1 and m are an integer of 1 to 8, when R3 represents the combination of —(CH2CH2O)1— and —(CH2CH(CH3)O)m—, the sum of 1 and m is an integer of 8 or less, X1 represents a carboxyl group or a sulfone group;
• in the general formulae (2) and (3), R4 represents an alkyl group having 8 to 16 carbon atoms, Z is a functional group represented by the chemical formula (i) or (ii) below, Y1 represents —(CH2CH2O)n—, —(CH2CH(CH3)O)p—, or a combination of —(CH2CH2O)n— and —(CH2CH(CH3)O)p—, when Y1 represents —(CH2CH2O)n— or —(CH2CH(CH3)O)p—, n and p are an integer of 1 to 6, when Y1 represents the combination of —(CH2CH2O)n— and —(CH2CH(CH3)O)p—, sum of n and p is an integer of 6 or less, X2 represents a phosphoric acid group or a sulfone group;
• and
• in the general formulae (4) to (7), each of R5 and R6 represents a hydrogen atom, a hydroxyl group, or an alkyl group having 8 to 16 carbon atoms, each of Y2 and Y3 represents —(CH2CH2O)q—, (CH2CH(CH3)O)r—, or a combination of —(CH2CH2O)q— and —(CH2CH(CH3)O)r—, when Y2 or Y3 represents —(CH2CH2O)q— or —(CH2CH(CH3)O)r—, q and r are an integer of 1 to 6, when Y2 or Y3 represents the combination of —(CH2CH2O)q— and —(CH2CH(CH3)O)r—, the sum of q and r is an integer of 6 or less, and
• the second polishing composition includes colloidal silica, an acid, an anticorrosive, a completely saponified polyvinyl alcohol, and water, and general formulae (1) to (7). (i) and (ii) are as follows:
• is the polishing composition according to any one of

A method for polishing an object to form wiring in a semiconductor device, wherein the object has a barrier layer and a conductive layer in this order on an insulating layer having a trench, and the barrier layer and the conductive layer have a portion positioned outside the trench and a portion positioned inside the trench, respectively, the method characterized-by comprising:

• removing a part of the portion of the conductive layer positioned outside the trench by chemical mechanical polishing to expose an upper surface of the barrier layer, and
• removing the remaining part of the portion of the conductive layer positioned outside the trench and the portion of the barrier layer positioned outside the trench by chemical mechanical polishing to expose an upper surface of the insulating layer,
• wherein a first polishing composition is used in the chemical mechanical polishing to remove a part of the portion of the conductive layer positioned outside the trench, and a second polishing composition is used in the chemical mechanical polishing to remove the remaining part of the portion of the conductive layer positioned outside the trench and the portion of the barrier layer positioned outside the trench,
• the first polishing composition includes an a-amino acid, a benzotriazole derivative, a silicon oxide, a surfactant, an oxidizing agent and water, the benzotriazole derivative is represented by general formula (8):
• in the general formula (8), R7 represents an alkyl group having a carboxyl group, an alkyl group having a hydroxyl group and a tertiary amino group, an alkyl group having a hydroxyl group, or an alkyl group other than those, and
• the second polishing composition includes colloidal silica, an acid, an anticorrosive, a completely saonified polyvinyl alcohol, and water.