Lithographic apparatus and device manufacturing method

• US 20060012779A1
• Filed: 02/04/2005
• Published: 01/19/2006
• Est. Priority Date: 07/13/2004
• Status: Abandoned Application

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Hinnen, Paul Christiaan, Franciscus Van Haren, Richard Johannes, Gertrudus Simons, Hubertus Johannes
• Application Number:
  US11/050,457
• Publication Number:
  US 20060012779A1
• Time in Patent Office: Days
• US Class Current: 356/237.400
• CPC Class Codes: G03F 7/70283 Mask effects on the imaging process
• CPC Class Codes: G03F 7/70683 Mark designs
• CPC Class Codes: G03F 7/70733 Handling masks and workpieces, e.g. exchange of workpiece or mask, transport of workpiece or mask

Abstract

A lithographic apparatus and method comprise an illumination system arranged to provide a radiation beam, a support structure configured to support a product patterning device and a metrology target patterning device. The product patterning device imparts a radiation beam derived from the illumination system with a product pattern in its cross-section representing features of a product device to be formed. The metrology target patterning device imparts the radiation beam with a metrology target pattern in its cross-section representing at least one metrology target. The product patterning device is separate from the metrology target patterning device. A substrate table holds a substrate. A projection system project the radiation patterned by the product patterning device and the metrology target patterning device onto a target portion of the substrate. A metrology target patterning device controller adjusts the metrology target pattern independently of the product pattern.

Claims

1. A device manufacturing method, comprising:

(a) performing a first exposure using a first set of exposure settings to expose a substrate with a first pattern that forms a set of one or more metrology targets;

(b) inspecting a latent image of the one or more metrology targets formed on the substrate;

(c) deriving from the latent image a second set of exposure settings; and

(c) performing a second exposure using the second set of exposure settings to expose the substrate to a second pattern that forms a set of one or more product device features.

2. The method of claim 1, wherein step (b) comprises:

using as the latent image a detectable pattern left on a resist layer on the substrate after the resist layer has been exposure to the first pattern, but before any further processing or development of the resist layer.

3. The method of claim 1, further comprising:

carrying out the first exposure and the second exposure on a same resist layer of the substrate.

4. The method of claim 1, further comprising:

using at least one of image magnification, image translation, image focus, and radiation intensity as the exposure settings.

5. The method of claim 1, further comprising:

forming only metrology targets with the first pattern.

6. The method of claim 1, further comprising:

forming only product device features with the second pattern.

7. The method of claim 1, further comprising:

forming a first set of metrology targets with the first pattern; and

forming a second set of metrology targets, which are different from the first set, with the second pattern.

8. The method of claim 1, wherein the second set of exposure settings are compensation exposure settings.

9. A lithographic apparatus, comprising:

an illumination system that supplies a beam of radiation;

a control system that controls an array of individually controllable elements that pattern the beam;

a projection system that projects the patterned beam onto a target portion of a substrate; and

a detection system that detects features formed on the substrate,

wherein a first set of exposure settings are used by the control system to control the individually controllable elements during a first exposure to expose the substrate with a first pattern that forms a first set of one or more metrology targets,

wherein the detection system detects a latent image of the first set of the one or more metrology targets and generates a second set of exposure settings therefrom,

wherein the second set of exposure settings are used by the control system to control the individually controllable elements during a second exposure to expose the substrate with a second pattern that forms a second set of one or more metrology targets.

10. The lithographic apparatus of claim 9, wherein the latent image comprises a detectable pattern left on a resist layer on the substrate after the resist layer has been exposure to the first pattern, but before any further processing or development of the resist layer.

11. The lithographic apparatus of claim 9, wherein a same resist layer of the substrate is used to carryout the first exposure and the second exposure.

12. The lithographic apparatus of claim 9, wherein the exposure settings include at least one of image magnification, image translation, image focus, and radiation intensity.

13. The lithographic apparatus of claim 9, wherein the first pattern comprises metrology targets only.

14. The lithographic apparatus of claim 9, wherein the second pattern comprises product device features only.

15. The lithographic apparatus of claim 9, wherein the first pattern comprises a first set of metrology targets and the second pattern comprises a second set of metrology targets, different from the first set.

16. The lithographic apparatus of claim 9, wherein the second set of exposure settings are compensation exposure settings.