APPARATUS AND METHOD FOR MEASURING AT LEAST ONE OF ARRANGEMENT AND SHAPE OF SHOTS ON SUBSTRATE, EXPOSURE APPARATUS, AND DEVICE MANUFACTURING METHOD

• US 20070133864A1
• Filed: 12/07/2006
• Published: 06/14/2007
• Est. Priority Date: 12/08/2005
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Morimoto, Osamu
• Granted Patent: US 7,760,931 B2
• Time in Patent Office: Days
• US Class Current: 382/151
• CPC Class Codes: G03F 9/7003 Alignment type or strategy, e.g. leveling, global alignment
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/0006 using a design-rule based approach
• CPC Class Codes: H01L 21/67259 Position monitoring, e.g. misposition detection or presence detection

Abstract

An apparatus for measuring at least one of an arrangement and shape of shots formed on a substrate, comprises a scope configured to obtain an image of an alignment mark corresponding to a shot; and a calculating device configured to calculate a difference between a position of the alignment mark in the image obtained by the scope and a designed position of the alignment mark, obtain a non-linear component of the calculated difference with respect to each of a plurality of conditions, calculate an index indicating a stability of the non-linear component of each shot with respect to each of the plurality of conditions, and select, from the plurality of conditions, a condition for obtaining the non-linear component based on the calculated indices.

Claims

1. An apparatus for measuring at least one of arrangement and shape of shots formed on a substrate, said apparatus comprising:

a scope configured to obtain an image of an alignment mark corresponding to a shot; and

a calculating device configured to calculate a difference between a position of the alignment mark in the image obtained by said scope and a designed position of the alignment mark, obtain a non-linear component of the calculated difference with respect to each of a plurality of conditions,

calculate an index indicating a stability of the non-linear component of each shot with respect to each of the plurality of conditions, and

select, from the plurality of conditions, a condition for obtaining the non-linear component based on the calculated indices.

2. An apparatus according to claim 1, wherein said calculating device is configured to

select representative data of the non-linear component with respect to each of a plurality of substrates,

divide shots on the substrate into a plurality of groups based on the selected representative data, and

select, from the plurality of conditions, a condition for obtaining the non-linear component with respect to each of the plurality of groups.

3. An apparatus according to claim 1, wherein said calculating device is configured to calculate the index based on a variation in non-linear components of shots having a plurality of different shot numbers among a plurality of substrates, and an average, over the plurality of different shot numbers, of variations in non-linear components of shots having identical shot numbers among the plurality of substrates.

4. An apparatus according to claim 1, wherein said calculating device is configured to select, as the representative data, one of the largest non-linear component and the largest magnification of the substrate.

5. An apparatus according to claim 1, wherein each of the plurality of conditions includes a condition for obtaining the non-linear component of a given shot based on the non-linear component of a shot neighboring the given shot.

6. An exposure apparatus for exposing a substrate to a pattern, said apparatus comprising:

a stage configured to hold the substrate and to move;

an apparatus as defined in claim 1;

and

a controller configured to control movement of said stage based on at least one of arrangement and shape of shots on the substrate measured by said apparatus as defined in claim 1.

7. A method of manufacturing a device, said method comprising steps of:

exposing a substrate to a pattern using an exposure apparatus as defined in claim 6;

developing the exposed substrate; and

processing the developed substrate to manufacture the device.

8. A method of measuring at least one of arrangement and shape of shots formed on a substrate, said method comprising step of:

obtaining an image of an alignment mark corresponding to a shot;

calculating a difference between a position of the alignment mark in the image and a designed position of the recorded alignment mark;

obtaining a non-linear component of the calculated difference with respect to each of a plurality of conditions;

calculating an index indicating a stability of the non-linear component of each shot with respect to each of the plurality of conditions; and

selecting, from the plurality of conditions, a condition for obtaining the non-linear component based on the calculated indices.

9. A method according to claim 8, further comprising steps of:

selecting representative data of the non-linear component with respect to each of a plurality of substrates; and

dividing shots on the substrate into a plurality of groups based on the selected representative data,

wherein a condition for obtaining the non-linear component is selected from the plurality of conditions with respect to each of the plurality of groups.

10. A method according to claim 8, wherein said index calculating step calculates the index based on a variation in non-linear components of shots having a plurality of different shot numbers among a plurality of substrates, and an average, over the plurality of different shot numbers, of variations in non-linear components of shots having identical shot numbers among the plurality of substrates.

11. A method according to claim 9, wherein said representative data selecting step selects, as the representative data, one of the largest non-linear component and the largest magnification of the substrate.

12. A method according to claim 8, wherein each of the plurality of conditions includes a condition for obtaining the non-linear component of a given shot based on the non-linear component of a shot neighboring the given shot.

13. An apparatus for measuring at least one of arrangement and shape of shots formed on a substrate, said apparatus comprising:

detecting means for detecting a position of an alignment mark corresponding to a shot; and

first calculating means for calculating a difference between the detected position of the alignment mark and a designed position of the alignment mark;

second calculating means for calculating a non-linear component of the calculated difference with respect to each of a plurality of conditions;

third calculating means for calculating an index indicating a stability of the non-linear component of each shot with respect to each of the plurality of conditions; and

selecting means for selecting, from the plurality of conditions, a condition for obtaining the non-linear component based on the calculated indices.

14. An exposure apparatus for exposing a substrate to a pattern, said apparatus comprising:

positioning means for positioning the substrate;

an apparatus as defined in claim 13;

and

controlling means for controlling a position of said positioning means based on at least one of arrangement and shape of shots on the substrate measured by said apparatus as defined in claim 13.

15. A method of manufacturing a device, said method comprising steps of:

exposing a substrate to a pattern using an exposure apparatus as defined in claim 14;

developing the exposed substrate; and

processing the developed substrate to manufacture the device.

16. A method of measuring at least one of arrangement and shape of shots formed on a substrate, said method comprising steps of:

detecting a position of an alignment mark corresponding to a shot; and

calculating a difference between the detected position of the alignment mark and a designed position of the alignment mark;

calculating a non-linear component of the calculated difference with respect to each of a plurality of conditions;

calculating an index indicating a stability of the non-linear component of each shot with respect to each of the plurality of conditions; and

selecting, from the plurality of conditions, a condition for obtaining the non-linear component based on the calculated indices.