Level Sensor of Exposure Apparatus and Wafer-Leveling Methods Using the Same

• US 20140152991A1
• Filed: 05/24/2013
• Published: 06/05/2014
• Est. Priority Date: 07/24/2012
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Heo, Jinseok, Yeo, Jeongho
• Application Number:
  US13/901,652
• Publication Number:
  US 20140152991A1
• Time in Patent Office: Days
• US Class Current: 356/445
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures
• CPC Class Codes: G01B 11/26 for measuring angles or tapers; for testing the alignment of axes
• CPC Class Codes: G03F 9/7034 Leveling

Abstract

A level sensor of an exposure apparatus includes a light source that generates light that is illuminated onto a top surface of a wafer, a projection part provided in a path of incident light propagating from the light source to the wafer and having a single first slit, a detection part provided in a path of light reflected from the wafer and having a single second slit, and a detector that detects the reflected light that is incident on the second slit of the detection part.

Claims

1. A level sensor of an exposure apparatus, comprising:

a light source that generates light that is illuminated onto a top surface of a wafer;

a projection part provided in a path of incident light propagating from the light source to the wafer, the projection part having a single first slit;

a detection part provided in a path of reflected light that is reflected from the wafer, the detection part having a single second slit; and

a detector that detects the reflected light that passes through the second slit of the detection part.

2. The level sensor of claim 1, wherein the detector comprises an imaging device configured to sense the reflected light two-dimensionally.

3. The level sensor of claim 2, wherein the imaging device comprises a charge-coupled device.

4. The level sensor of claim 1, wherein the detector is configured to sense a change in intensity of the reflected light.

5. The level sensor of claim 1, wherein the light source comprises a halogen lamp.

6. The level sensor of claim 1, wherein the first slit has a width of 4 mm or less and a length of 26 mm or more.

7. The level sensor of claim 1, wherein the second slit has a width and a length that are equal to or greater than a width and a length of the first slit, respectively.

8. The level sensor of claim 1, wherein the detector is in contact with a first surface of the detection part opposite to a second surface of the detection part onto which the reflected light is incident.

9-14. -14. (canceled)