Method for producing masks for photolithography and the use of such masks

• US 7,625,675 B2
• Filed: 02/22/2005
• Issued: 12/01/2009
• Est. Priority Date: 02/25/2004
• Status: Expired due to Fees

• Current Assignee: Oerlikon Trading AG, Trubbach
• Original Assignee: Oerlikon Trading AG, Trubbach
• Inventors: Wiki, Max, Lanker, Michael
• Primary Examiner(s): Huff; Mark F
• Assistant Examiner(s): JELSMA, JONATHAN G
• Application Number:
  US11/063,271
• Publication Number:
  US 20050202324A1
• Time in Patent Office: 1,743 Days
• Field of Search: 430/5
• US Class Current: 430/5
• CPC Class Codes: G03F 1/50 Mask blanks not covered by G03F1/20 - G03F1/34; Preparation thereof
• CPC Class Codes: G03F 7/7035 Proximity or contact printers

Abstract

A mask for photolithography methods comprises opaque and transparent areas as well as a surface structure. For the contact with a substrate (10) to be exposed at least a few opaque areas are incorporated and at least a few transparent areas are arranged in a spaced fashion and are deep-etched down to a structural depth. In a further embodiment at least one transparent area is designed as a positively resting area (12). The structural depth in the deep-etched areas is greater than the thickness of the surface structure, at least greater than or equal to 1 μm.

Claims

1. Mask for photolithography method comprising opaque and transparent areas and a surface structure, characterized in that for the purpose of establishing a contact to a substrate (10) that is supposed to be exposed, at least a few opaque areas are designed as areas resting positively on said substrate and at least a few transparent areas within a portion of the mask facing entirely to said substrate are arranged spaced and deep-etched down to a structural depth, and at least one transparent area is designed as a positively resting area for resting on said substrate, wherein the structural depth in the deep-etched areas is greater than the thickness of the surface structure.

2. Mask pursuant to claim 1, characterized in that the positively resting areas are essentially identical to those areas that are provided for the exposure of high resolution structures.

3. Mask pursuant to claim 1, characterized in that the structural depth in the deep-etched areas is at least greater than or equal to 1 μ

m.

4. Mask pursuant to claim 1, characterized in that the ratio of the width of the contact areas to the structural depth in any case is better than 1:

2.

5. Mask pursuant to claim 1, characterized in that the surface ratio of contact areas to spaced areas is at least 1:

100.

6. Mask pursuant to claim 1, consisting of glass with structuring made of chrome.

7. Method for producing a mask pursuant to claim 1 comprising the following steps:

Treatment of the mask to be structured with a bonding agent;

Application of photoresist on the mask;

Masking of the areas that are not supposed to be deep-etched;

Exposure of the photoresist;

Development of the exposed photoresists;

Etching of the areas not covered by the photoresist;

Cleaning of the photomask.

8. A lithography method comprising a mask pursuant to claim 1 with the following steps:

Provision of a substrate (10) that is to be structured with a photo-sensitive layer;

Application of a mask on the substrate such that opaque contact areas and transparent spaced areas are implemented;

Exposure of the substrate through the mask;

Development of the photosensitive layer.

9. The mask pursuant to claim 1, characterized in that the structural depth in the deep-etched areas is 5 μ

m.

10. The mask pursuant to claim 1, characterized in that the ratio of the width of the contact area to the structural depth in any case is 1:

1 or above.

11. The mask pursuant to claim 1, characterized in that the surface ratio of contact areas to spaced areas is 1:

10 or above.

12. The mask pursuant to claim 6, wherein the glass is quartz glass.