Position detecting method and apparatus

• US 5,148,035 A
• Filed: 11/12/1991
• Issued: 09/15/1992
• Est. Priority Date: 09/09/1988
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hattori, Jun, Suda, Shigeyuki
• Primary Examiner(s): Nelms, David C.
• Application Number:
  US07/789,630
• Time in Patent Office: 308 Days
• Field of Search: 250/548, 250/557, 356/400, 356/401
• US Class Current: 250/548
• CPC Class Codes: G03F 9/7049 Technique, e.g. interferometric

Abstract

A device for detecting a positional relationship between opposed first and second objects, with respect to a first direction perpendicular to the opposing direction. The device includes a light source for projecting light to the first and second objects, a photodetecting portion for receiving light from one of the first and second objects irradiated with the light from the light source, the photodetecting portion being operable to detect a predetermined parameter related to the light, which parameter is changeable with the positional relationship between the first and second objects with respect to the first direction, a first position detecting system for detecting a positional relationship between the first and second objects, with respect to a second direction perpendicular to the opposing direction of the first and second objects and having an angle with respect to the first direction, and a second position detecting system for detecting the positional relationship between the first and second objects with respect to the first direction, on the basis of the detection by the photodetecting system and the first position detecting system.

Claims

1. A device for detecting a positional relationship between first and second objects opposed in an opposing direction, with respect to a first direction perpendicular to the opposing direction, said device comprising:

light source means for projecting light to illuminate the first and second objects;

photodetecting means for receiving light from the illuminated first and second objects, said photodetecting means comprising means for detecting a position of incidence of the light upon a predetermined plane, which position changes with a change in the positional relationship between the first and second objects with respect to the first direction and with respect to a second direction which is perpendicular to both the opposing direction and to the first direction;

position detecting means for detecting the positional relationship between the first and second objects, with respect to the second direction; and

means for determining the positional relationship between the first and second objects with respect to the first direction, on the basis of the detection by said photodetecting means and by said position detecting means.

2. A device for detecting a positional relationship between first and second objects opposed in an opposing direction, with respect to a first direction perpendicular to the opposing direction, said device comprising:

light source means for projecting light to illuminate the first and second objects;

a first sensor comprising a light receiving surface for receiving first light from the illuminated first and second objects, said first sensor detecting a position of incidence of the received first light upon said first light receiving surface, which position changes with a change in the positional relationship between the first and second objects with respect to the first direction and with respect to a second direction which is perpendicular to both the opposing direction and to the first direction;

a second sensor comprising a second light receiving surface for receiving second light, different from the first light, from the illuminated first and second objects, said second sensor detecting a position of incidence of the received second light upon said second light receiving surface, which position changes with a change in the positional relationship between the first and second objects, with respect to the second direction; and

determining means for determining the positional relationship between the first and second objects with respect to the first direction, on the basis of the detection by said first and second sensors.

3. A device according to claim 2, said determining means further comprising means for determining the positional relationship between the first and second objects with respect to the second direction, on the basis of the detection by said first and second sensors.

4. A method of detecting a positional relationship between first and second objects opposed in an opposing direction, with respect to a first direction perpendicular to the opposing direction, said method comprising the steps of:

projecting light to illuminate the first and second objects;

receiving light from the illuminated first and second objects and detecting a predetermined parameter related to the received light, which parameter changes with a change in the positional relationship between the first and second objects with respect to the first direction and with respect to a second direction, perpendicular to the opposing direction and different from the first direction;

detecting the positional relationship between the first and second objects, with respect to the second direction; and

determining the positional relationship between the first and second objects with respect to the first direction, on the basis of the detection of the predetermined parameter and the detection of the positional relationship.

5. In a position detecting method wherein a radiation beam is projected to a mark having an optical power formed on a substrate so that the radiation beam is converged on a predetermined plane and wherein a position of the substrate in a predetermined direction is determined on the basis of a position of the radiation beam on the predetermined plane, the improvement comprising:

determining the position of the substrate in the predetermined direction on the basis of a position of the substrate in a direction perpendicular to the predetermined direction and the position of the radiation beam on the predetermined plane.

6. In a semiconductor device manufacturing method wherein positional deviation between an original including an alignment pattern having an optical power and a substrate including an alignment mark having an optical power is detected with respect to a first direction by using the alignment pattern and the alignment mark and, after correction of the positional deviation, the substrate is exposed to a circuit pattern of the original with radiation, the improvement comprising:

converging a projected radiation beam by the alignment pattern and the alignment mark on a predetermined plane;

detecting the position of the radiation beam on the predetermined plane;

detecting the position of the substrate relative to the original with respect to a second direction perpendicular to the first direction; and

detecting the positional deviation between the original and the substrate on the basis of the position of the radiation beam on the predetermined plane and the relative position of the substrate with respect to the second direction.

7. In a semiconductor device manufacturing method wherein positional deviation between an original having first and second alignment patterns and a substrate having first and second alignment marks is detected with respect to each of a first direction and a second direction perpendicular to the first direction by using the first and second alignment patterns and the first and second alignment marks and, after correction of the positional deviation, the substrate is exposed to a circuit pattern of the original with radiation, and wherein the first alignment pattern and the first alignment mark each has an optical power with respect to the first direction, while the second alignment pattern and the second alignment mark each has an optical power with respect to the second direction, the improvement comprising:

converging a projected first radiation beam by the first alignment pattern and the first alignment mark on a first predetermined plane;

detecting the position of the first radiation beam on the first plane;

converging a projected second radiation beam by the second alignment pattern and the second alignment mark on a second predetermined plane;

detecting the position of the second radiation beam on the second plane;

detecting a positional deviation between the original and the substrate with respect to the first direction on the basis of the position of the first radiation beam on the first plane and the position of the second radiation beam on the second plane; and

detecting a positional deviation between the original and the substrate with respect to the second direction on the basis of the position of the first radiation beam on the first plane and the position of the second radiation beam on the second plane.

8. In a semiconductor device manufacturing method wherein a radiation beam is projected to a mark having an optical power formed on a substrate so that the radiation beam is converged on a predetermined plane, wherein positional deviation of the substrate in a predetermined direction is determined on the basis of a position of the radiation beam on the predetermined plane, and wherein, after correction of the positional deviation, a circuit pattern is printed on the substrate, the improvement comprising:

determining the position of the substrate in the predetermined direction on the basis of a position of the substrate in a direction perpendicular to the predetermined direction and the position of the radiation beam on the predetermined plane.

9. A position determining method for determining the position of a substrate in a first direction by detecting an alignment mark of the substrate, said method comprising the steps of:

detecting the position of the substrate in a second direction which substantially perpendicularly intersects the first direction; and

determining the position of the substrate in the first direction on the basis of the detection of the alignment mark and the detection of the position of the substrate in the second direction.

10. A method according to claim 9, further comprising using a zone plate pattern as the alignment mark.

11. A method according to claim 10, wherein said step of detecting the position of the substrate in the second direction is based on a second mark defined by a second zone plate pattern provided on the substrate.

12. A semiconductor device manufacturing method, wherein the position of a water in a first direction is adjusted by using an alignment mark formed on the wafer and then a circuit pattern is printed on the wafer to manufacture a semiconductor device, said method comprising the steps of:

photoelectrically detecting the alignment mark of the wafer;

detecting the position of the wafer in a second direction which substantially perpendicularly intersects the first direction;

determining an error in the position of the wafer in the first direction with respect to a predetermined position, on the basis of the detection of the alignment mark and the detection of the position of the wafer in the second direction; and

adjusting the position of the wafer so as to correct the error.

13. A method according to claim 12, further comprising using a zone plate pattern as the alignment mark.

14. A method according to claim 13, wherein said step of detecting the position of the wafer in the second direction is based on a second mark defined by a second zone plate pattern provided on the wafer.

15. An alignment and exposure apparatus for aligning a wafer in a first direction by using an alignment mark of the wafer and for printing a circuit pattern on the aligned wafer, said apparatus comprising:

illuminating means for illuminating the alignment mark of the wafer;

signal forming means for photoelectrically converting light from the illuminated alignment mark of the wafer and for forming a signal which is dependent on the position of the wafer in the first direction and the position of the wafer in a second direction which substantially perpendicularly intersects the first direction;

position determining means for determining the position of the wafer in the first direction on the basis of the signal and the position of the wafer in the second direction;

means for aligning the wafer in the first direction on the basis of the determination; and

means for exposing the wafer to the circuit pattern to print the circuit pattern on the wafer.

16. An apparatus according to claim 15, wherein the alignment mark of the wafer comprises a zone plate pattern.

17. An alignment and exposure apparatus for aligning a wafer in first and second orthogonal directions by using first and second alignment marks of the wafer and for printing a circuit pattern on the aligned wafer, said apparatus comprising:

illuminating means for illuminating the first and second alignment marks of the wafer;

signal forming means for photoelectrically converting light beams from the illuminated first and second alignment marks of the wafer and for forming first and second signals, respectively, each being dependent on the position of the wafer in the first direction and the position of the wafer in a second direction which substantially perpendicularly intersects the first direction;

position determining means for processing the first signal in accordance with the second signal to determine the position of the wafer in the first direction and for processing the second signal in accordance with the first signal to determine the position of the wafer in the second direction;

means for aligning the wafer in the first and second directions on the basis of the determination; and

means for exposing the wafer to the circuit pattern to print the circuit pattern on the wafer.

18. An apparatus according to claim 17, wherein each of the first and second alignment marks comprise a zone plate pattern.

19. An alignment and exposure apparatus for aligning a wafer in first and second orthogonal directions by using first and second alignment marks of the wafer and first and second alignment patterns of a mask and for exposing the wafer to a circuit pattern of the mark, wherein each of the first alignment mark and the first alignment pattern has an optical power with respect to the first direction and wherein each of the second alignment mark and the second alignment pattern has an optical power with respect to the first direction, said apparatus comprising:

a first alignment optical system for illuminating the first alignment pattern of the mask and the first alignment mark of the wafer to produce a first light beam influenced by the optical powers of the first alignment pattern and the first alignment mark;

first signal forming means for photoelectrically converting the first light beam to form a first signal which is dependent on the position of the wafer in the first and second directions;

a second alignment optical system for illuminating the second alignment pattern of the mask and the second alignment mark of the wafer to produce a second light beam influenced by the optical powers of the second alignment pattern and the second alignment mark;

second signal forming means for photoelectrically converting the second light beam to form a second signal which is dependent on the position of the wafer in the first and second directions;

position determining means for processing the first signal in accordance with the second signal to determine the position of the wafer in the first direction and for processing the second signal in accordance with the first signal to determine the position of the wafer in the second direction;

means for aligning the wafer in the first and second directions on the basis of the determination; and

means for exposing the wafer to the circuit pattern to print the circuit pattern on the wafer.