Pattern forming method and phase shift mask manufacturing method

Abstract

A light-shielding layer over a transparent substrate is processed into a predetermined pattern by first etching and then a recess is formed in an underlying layer below the light-shielding layer by second etching using at least the light-shielding layer as a mask. Subsequently, a defect inspection of the recess is performed. If, as a result of the inspection, a residue defect is detected at the recess otherwise formed in the underlying layer below the light-shielding layer, defect portion data of a pattern of a region including a residue-defect portion is produced and a repairing resist pattern is formed on the light-shielding layer based on the defect portion data. Then, third etching is applied to the underlying layer below the light-shielding layer using the light-shielding layer and the repairing resist pattern as a mask, thereby repairing the residue-defect portion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A to 1C show the general structures of auxiliary pattern type phase shift masks, wherein FIG. 1A is a plan view of the auxiliary pattern type phase shift mask (the plan view is the same for both masks) and FIGS. 1B and 1C respectively show sections, each taken along a chain line A in FIG. 1A, in terms of two examples;

FIGS. 2A to 2F are process diagrams showing a conventional phase shift mask manufacturing method;

FIGS. 3A to 3G are process diagrams showing a conventional halftone type phase shift mask manufacturing method;

FIGS. 4A to 4J are process diagrams showing a first embodiment of a phase shift mask manufacturing method according to this invention (in the case of an auxiliary pattern type phase shift mask);

FIG. 5A is a plan view showing the state of a residue defect detected by a defect inspection in the first embodiment of the phase shift mask manufacturing method according to this invention and FIG. 5B is a plan view showing defect portion data of a pattern of a region including a residue-defect portion;

FIGS. 6A to 6L are process diagrams showing a second embodiment of a phase shift mask manufacturing method according to this invention (in the case of a halftone type phase shift mask); and

FIG. 7A is a plan view showing the state of a residue defect detected by a defect inspection in the second embodiment of the phase shift mask manufacturing method according to this invention and FIG. 7B is a plan view showing defect portion data of a pattern of a region including a residue-defect portion.

Claims

1. A pattern forming method comprising the steps of: forming a resist pattern on a coating layer on a substrate;applying a first etching to said coating layer using said resist pattern as a mask to form a pattern on said coating layer;applying a second etching to an underlying layer which lies below said coating layer using at least said coating layer as a mask to form a recess in said underlying layer;performing a defect inspection for said recess;producing defect portion data of a pattern including a residue-defect portion when a residue defect of said recess is detected by said defect inspection;forming a repairing resist pattern on said coating layer based on said defect portion data; andapplying a third etching to said underlying layer using said coating layer and said repairing resist pattern as a mask to form said recess in said underlying layer, thereby repairing said residue-defect portion.

2. A pattern forming method according to claim 1, wherein said underlying layer is said substrate.

3. A pattern forming method according to claim 1, wherein said underlying layer is a second coating layer formed between said coating layer and said substrate.

4. A pattern forming method according to claim 1, wherein said defect portion data is produced in a manner that the defect portion data contain a pattern data representing a recess of a size which is larger than the size for the recess to be formed in said underlying layer, based on a coordinate data of said residue-defect.

5. A method for manufacturing a phase shift mask comprising a light-shielding layer over a transparent substrate, which method comprises the steps of: forming a resist pattern on said light-shielding layer;applying a first etching to said light-shielding layer using said resist pattern as a mask to form a pattern on said light-shielding layer;applying a second etching to an underlying layer which lies below said light-shielding layer using at least said light-shielding layer as a mask to form a recess in said underlying layer;performing a defect inspection for said recess;producing defect portion data of a pattern including a residue-defect portion when a residue defect of said recess is detected by said defect inspection;forming a repairing resist pattern on said light-shielding layer based on said defect portion data; andapplying a third etching to said underlying layer using said light-shielding layer and said repairing resist pattern as a mask to form said recess in said underlying layer, thereby repairing said residue-defect portion.

6. A phase shift mask manufacturing method according to claim 5, wherein said underlying layer is said transparent substrate.

7. A phase shift mask manufacturing method according to claim 5, wherein said underlying layer is a light-semitransmitting layer formed between said light-shielding layer and said transparent substrate.

8. A phase shift mask manufacturing method according to claim 5, wherein said defect portion data is produced in a manner that the defect portion data contain a pattern data representing a recess of a size which is larger than the size for the recess to be formed in said underlying layer, based on a coordinate data of said residue-defect.