Fabrication method of semiconductor integrated circuit device

Claim 2

Method for manufacturing a semiconductor IC device, comprising the steps of: (a) depositing a photoresist over a semiconductor wafer so as to form a photoresist film; and (b) transferring an integrated circuit pattern over a photomask to the semiconductor wafer by irradiating the photoresist film over said semiconductor wafer with an off-axis illumination through an optical reduction projection system, wherein said photomask comprises: (i) a mask substrate; (ii) a halftone film over a main surface of the mask substrate; (iii) a plurality of main apertures in the halftone film to transfer the integrated circuit pattern corresponding to a plurality of hole patterns having substantially a same size over the wafer; and (iv) a plurality of auxiliary apertures in the halftone film not resolved over said semiconductor wafer, wherein said main apertures and said auxiliary apertures are disposed periodically as a whole.

Claim 3

Method for manufacturing a semiconductor IC device according to claim 1 , wherein said main apertures and said auxiliary apertures are disposed at intersecting points of first and second virtual lines perpendicularly crossing with each other.

Claim 4

Method for manufacturing a semiconductor IC device according to claim 2 , wherein pitches of said first and second virtual lines are identical in first and second regions over the main surface of said photomask, and positions of said first and second virtual lines in said first and second regions are shifted from each other.

Claim 5

Method for manufacturing a semiconductor IC device according to claim 2 , wherein said first virtual lines are different from said second virtual lines in their pitches.

Claim 6

Method for manufacturing a semiconductor IC device according to claim 4 , wherein a type of said off-axis illumination is chosen in accordance with the pitches of the first and second virtual lines.

Claim 7

Method for manufacturing a semiconductor IC device according to claim 2 , wherein said main apertures and said auxiliary apertures are disposed at the intersecting points of said first and second virtual lines in a first region, while said main apertures and said auxiliary apertures are disposed off the intersecting points in a second region.

Claim 8

Method for manufacturing a semiconductor IC device according to claim 1 , wherein a proximity correction is applied to first main apertures, of said main apertures, or to first auxiliary apertures, of said auxiliary apertures.

Claim 9

Method for manufacturing a semiconductor IC device according to claim 1 , wherein said auxiliary apertures are disposed around a densely disposed region of said main apertures.

Claim 10

Method for manufacturing a semiconductor IC device according to claim 1 , wherein said off-axis illumination is a quadrupole illumination or an annular illumination.

Claim 11

Method for manufacturing a semiconductor IC device according to claim 1 , wherein the photomask has a dense region and a diffused region where the main apertures are disposed respectively in a higher density and lower density.

Claim 12

Method for manufacturing a semiconductor IC device, comprising the steps of: (a) depositing a photoresist over a semiconductor wafer so as to form a photoresist film; and (b) transferring an integrated circuit pattern over a photomask to the semiconductor wafer by irradiating the photoresist film over said semiconductor wafer with an off-axis illumination through an optical reduction projection system, wherein said photomask comprises: (i) a mask substrate; (ii) a halftone film over a main surface of the mask substrate; (iii) a plurality of main apertures in the halftone film to transfer the integrated circuit pattern corresponding to a plurality of hole patterns having substantially a same size over the wafer; and (iv) a plurality of auxiliary apertures in the halftone film not resolved over said semiconductor wafer, wherein said main apertures and said auxiliary apertures are disposed periodically as a whole, and a proximity correction is applied to at least one of first main apertures of said main apertures and first auxiliary apertures of said auxiliary apertures.

Claim 13

Method for manufacturing a semiconductor IC device, comprising the steps of: (a) depositing a photoresist over a semiconductor wafer so as to form a photoresist film; and (b) transferring an integrated circuit pattern over a photomask to the semiconductor wafer by irradiating the photoresist film over said semiconductor wafer with an off-axis illumination through an optical reduction projection system, wherein said photomask comprises: (i) a mask substrate; (ii) a halftone film over a main surface of the mask substrate; (iii) a plurality of main apertures in the halftone film to transfer the integrated circuit pattern corresponding to a plurality of hole patterns having substantially a same size over the wafer; and (iv) a plurality of auxiliary apertures in the halftone film not resolved over said semiconductor wafer, wherein said main apertures and said auxiliary apertures are disposed periodically as a whole, and a proximity correction is applied to at least one of first main apertures of said main apertures and first auxiliary apertures of said auxiliary apertures.

Claim 14

Method for manufacturing a semiconductor IC device according to claim 11 , wherein said main apertures and said auxiliary apertures are disposed at intersecting points of first and second virtual lines perpendicularly crossing with each other.

Claim 15

Method for manufacturing a semiconductor IC device according to claim 12 , wherein pitches of said first and second virtual lines in first and second regions over the main surface of said photomask are identical and positions of said first and second virtual lines in said first and second regions are shifted from each other.

Claim 16

Method for manufacturing a semiconductor IC device according to claim 12 , wherein said first virtual lines are different from said second virtual lines in their pitches.

Claim 17

Method for manufacturing a semiconductor IC device according to claim 14 , wherein a type of said off-axis illumination is chosen in accordance with the pitches of the first and second virtual lines.

Claim 18

Method for manufacturing a semiconductor IC device according to claim 12 , wherein the said main apertures and said auxiliary apertures are disposed at the intersecting points of said first and second virtual lines in a first region, while said main apertures and said auxiliary apertures are disposed off the intersecting points in a second region.

Claim 19

Method for manufacturing a semiconductor IC device according to claim 12 , wherein said auxiliary apertures are disposed around a densely disposed region of the said main apertures.

Claim 20

Method for manufacturing a semiconductor IC device according to claim 12 , wherein said off-axis illumination is quadrupole illumination or annular illumination.

Claim 21

Method for manufacturing a semiconductor IC device according to claim 12 , wherein the main surface of the mask substrate has a dense region and a diffused region where the main apertures are disposed respectively in a higher density and a lower density.

Claim 22

Method for manufacturing a semiconductor IC device, comprising the steps of: (a) depositing a photoresist over a semiconductor wafer so as to form a photoresist film; and (b) transferring an integrated circuit pattern over a photomask to the semiconductor wafer by irradiating the photoresist film over said semiconductor wafer with an off-axis illumination through an optical reduction projection system, wherein said photomask comprises: (i) a mask substrate; (ii) a halftone film over a main surface of the mask substrate; (iii) a plurality of main apertures in the halftone film to transfer the integrated circuit pattern corresponding to a plurality of hole patterns having substantially a same size over the wafer; and (iv) a plurality of auxiliary apertures in the halftone film not resolved over semiconductor wafer, wherein said main apertures and said auxiliary apertures are disposed periodically as a whole; and said auxiliary apertures are disposed in a region which is broadened for a length of integer times a pitch of said integrated circuit pattern with reference to said main apertures.

Claim 23

Method for manufacturing a semiconductor IC device, comprising the steps of: (a) depositing a photoresist over a semiconductor wafer so as to form a photoresist film; and (b) transferring an integrated circuit pattern over a photomask to the semiconductor wafer by irradiating the photoresist film over said semiconductor wafer with an off-axis illumination through an optical reduction projection system, wherein said photomask comprises: (i) a mask substrate; (ii) a halftone film over a main surface of the mask substrate; (iii) a plurality of main apertures in the halftone film to transfer the integrated circuit pattern corresponding to a plurality of hole patterns having substantially a same size over the wafer; and (iv) a plurality of auxiliary apertures in the halftone film not resolved over semiconductor wafer, wherein said main apertures and said auxiliary apertures are disposed periodically as a whole; and said auxiliary apertures are disposed in a region which is broadened for a length of integer times a pitch of said integrated circuit pattern with reference to said main apertures.

Claim 24

Method for manufacturing a semiconductor IC device according to claim 20 , wherein said main apertures and said auxiliary apertures are disposed at intersecting points of first and second virtual lines crossing perpendicularly with each other.

Claim 25

Method for manufacturing a semiconductor IC device according to claim 21 , wherein pitches of said first and second virtual lines are different for every region over the main surface of said photomask.

Claim 26

Method for manufacturing a semiconductor IC device according to claim 21 , wherein said first virtual lines are different from said second virtual lines in their pitches.

Claim 27

Method for manufacturing a semiconductor IC device according to claim 23 , wherein a type of said off-axis illumination is chosen in accordance with the pitches of the first and second virtual lines.

Claim 28

Method for manufacturing a semiconductor IC device according to claim 21 , wherein said main apertures and said auxiliary apertures are disposed at the intersecting points of said first and second virtual lines in a first region, while said main apertures and said auxiliary apertures are disposed off the intersecting points in a second region.

Claim 29

Method for manufacturing a semiconductor IC device according to claim 20 , wherein said off-axis illumination is quadrupole illumination or annular illumination.

Claim 30

Method for manufacturing a semiconductor IC device according to claim 20 , wherein the main surface of the mask substrate has a dense region and a diffused region where the main apertures are disposed respectively in a higher density and a lower density.