Method of repairing a mask with high electron scattering and low electron absorption properties

• US 6,440,615 B1
• Filed: 02/09/2000
• Issued: 08/27/2002
• Est. Priority Date: 02/09/1999
• Status: Expired due to Fees

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Shimizu, Sumito
• Primary Examiner(s): ROSASCO, STEPHEN D
• Application Number:
  US09/500,560
• Time in Patent Office: 930 Days
• Field of Search: 430/5, 216/63, 216/67, 427/255.28
• US Class Current: 430/5
• CPC Class Codes: G03F 1/20 Masks or mask blanks for imaging by charged particle beam [CPB] radiation, e.g. by electron beam; Preparation thereof
• CPC Class Codes: G03F 1/74 by charged particle beam [CPB], e.g. focused ion beam

Abstract

A method to repair a scattering stencil type mask having a high electron beam scattering property and low electron absorption. In order to correct a defect caused at the time of manufacturing of the mask, which is being used when a reduction projection image is transferred onto a substrate and has a pattern projection portion comprising an electron beam scattering material, a repair membrane is formed in the defective portion of the mask by irradiating a charged particle beam to said defect while a gas including substances having high scattering properties are supplied to the close vicinity of the defective portion.

Claims

1. A method of repairing a defect of a mask used in a projection lithography system having a pattern with high electron scattering property and low electron absorption, comprising following steps:

detecting a defect area in the pattern of manufactured mask;

supplying a gas comprising at least one compound material including halogen for use as an etching agent for silicon, said supplied gas including one of the following;

iodine, chlorine, xenon fluoride, carbon tetrachloride group, carbon trichloride group, carbon tetrafluoride group, or carbon trifluoride group;

said supplied gas being first diluted by an inert gas and then supplied to the vicinity of the defect area with an adjusted flow rate; and

irradiating a charged particle beam to said defect area.

2. A method of repairing a defect of a mask used in projection lithography system, having a pattern with high electron scattering property and low electron absorption, comprising following steps:

detecting a defective portion in the pattern when transferred to a wafer; and

forming a membrane in the defective portion, the membrane composed of a material, main element of which is silicon or carbon, and including substances comprising at least one atom of nonmetal Vb group atoms and semiconductor atoms except silicon, a nonmetal atom and a metal atom.

3. A method of claim 2, wherein the membrane provides forward-scattering of electrons greater than 10 mrad when being illuminated by an electron beam.

4. A method of claim 2, wherein, when an electron beam is irradiated to the membrane, a number of electrons which are forward-scattered within electron beam irradiation angle range of 10 mrad is less than 1.5% of total number of irradiated electrons.

5. A method of claim 2, wherein the composition quantity ratio for containing at least one atom of the nonmetal Vb group atoms and the semiconductor atoms except silicon, the nonmetal atom, and the metal atom in the substances is less than 92% of all atoms.

6. A method of claim 5, wherein the membrane includes phosphorous and the composition quantity ratio of phosphorous atoms is less than 92% of all atoms.

7. A method of claim 5, wherein the membrane includes titanium and the composition quantity ratio of titanium atoms is less than 73% of all atoms.

8. A method of claim 5, wherein the membrane includes gold and the composition quantity ratio of gold atoms is less than 20% of all atoms.

9. A method of claim 5, wherein the membrane includes platinum and the composition quantity ratio of platinum atoms is less than 15% of all atoms.

10. A method of repairing a defective portion of a mask used in projection lithography system, having a pattern with high electron scattering property and low electron absorption, by forming a membrane selectively in a defective portion, the method comprising following steps:

detecting the defective portion;

supplying a plurality of gasified substances comprising electron beam scattering substances mixed at a predetermined mixture ratio to the vicinity of the defective portion individually; and

irradiating the charged particle beam to the defective portion.

11. A method of claim 10, further comprising creating in the vicinity of the defective portion a precursor gas atmosphere with a predetermined density and mixture composition ratio.

12. A method of claim 10, wherein the substances comprising the electron beam scattering substances are mixed at a predetermined mixture ratio, and their mixture supplied to the vicinity of the defective portion.

13. A method of claim 12, wherein the mixture of substances is further gasified.

14. A method of claim 10, wherein the substances are mixed in advance in order to supply a mixture with a predetermined density and mixture composition ratio to the defective portion.

15. A method of claim 14, wherein the mixture of the substances is further gasified.

16. A method of repairing a defective portion of a mask used in projection lithography system, having a pattern with high electron scattering property and low electron absorption, by forming a membrane selectively in a defective portion, the method comprising following steps:

detecting the defective portion;

forming in the defective portion a membrane composed of a substance, main element of which is carbon or silicon; and

forming a repair reinforcement layer on the membrane.

17. A method of claim 16, wherein the repair reinforcement layer is composed of substances containing semiconductor atoms except silicon, non-metal atoms, or metal atoms.

18. A structure for repairing a defective portion of a mask used in projection lithography system, the mask having a pattern with high electron scattering property and low electron absorption, the structure comprising a membrane formed in the defective portion and composed of a material, a main element of which is silicon or carbon, comprising substances containing at least one atom of nonmetal Vb group atoms and semiconductor atoms except silicon, a nonmetal atom, and a metal atom in a defect portion.

19. A structure for repairing a defective portion of a mask used in projection lithography system, the mask having a pattern with high electron scattering property and low electron absorption, the structure comprising;

a membrane formed in the defective portion and composed of a substance main element of which is carbon or silicon; and

a repair reinforcement layer composed of substances containing semiconductor atoms except silicon, non-metal atoms, or metal atoms, and formed on the membrane.