Apparatus for optical emission spectroscopy

• US 10,408,680 B2
• Filed: 01/28/2016
• Issued: 09/10/2019
• Est. Priority Date: 01/28/2015
• Status: Active Grant

• Current Assignee: Industry Academic Cooperation Foundation
• Original Assignee: Industry Academic Cooperation Foundation
• Inventors: Yun, Ilgu, Lee, Sang Myung
• Primary Examiner(s): Yu, Yuechuan
• Application Number:
  US15/008,856
• Publication Number:
  US 20160216155A1
• Time in Patent Office: 1,321 Days
• CPC Class Codes: G01J 3/0208 using focussing or collimating elements, e.g. lenses or mirrors; performing aberration correction
• CPC Class Codes: G01J 3/0216 using light concentrators or collectors or condensers
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/0235 using means for replacing an element by another, for replacing a filter or a grating
• CPC Class Codes: G01J 3/443 Emission spectrometry
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01J 37/32972 Spectral analysis

Abstract

Provided is an apparatus for optical emission spectroscopy. The apparatus for the optical emission spectroscopy includes a light collection unit configured to collect light within a plasma process chamber in which plasma is generated to process a substrate, a light transmission unit configured to transmit the collected light, and an analysis unit configured to analyze the light provided through the light transmission unit, thereby analyzing a plasma state. The light collection unit includes a light collection part configured to concentrate the light generated in the plasma process chamber and provide the concentrated light to the light transmission unit.

Claims

1. An apparatus for optical emission spectroscopy, comprising:

a light collection unit configured to collect light within a plasma process chamber in which plasma is generated to process a substrate, the light collection unit comprising a concave lens;

a light transmission unit configured to transmit the collected light; and

an analysis unit configured to analyze the light provided through the light transmission unit, thereby analyzing a plasma state,

wherein the light collection unit comprises a light collection part configured to concentrate the light generated in the plasma process chamber and provide the concentrated light to the light transmission unit,

wherein the concave lens is configured to expand an incident angle range of light that is incident from the inside of the plasma process chamber to concentrate the light,

wherein both a front surface of the concave lens facing the plasma process chamber and a rear surface opposite to the front surface of the concave lens are concave,

wherein the concave lens has a structure in which a curvature thereof in a horizontal direction is greater than a curvature thereof in a vertical direction,

wherein the concave lens has a front surface concave transverse section, a rear surface concave transverse section, and a rectangular vertical section,

wherein the rear surface concave transverse section of the concave lens is concave in the horizontal direction opposite to the curvature of the front surface concave transverse section of the concave lens,

wherein the horizontal direction is parallel to a top surface of the substrate, and the vertical direction is perpendicular to the top surface of the substrate, and

wherein a cross-section of the concave lens that is parallel to the top surface of the substrate is curved, and a cross-section of the concave lens that is perpendicular to the top surface of the substrate is not curved.

2. The apparatus of claim 1, wherein the light transmission unit comprises an optical fiber.

3. The apparatus of claim 1, further comprising a driving unit configured to move the light collection part to a front side of the light transmission unit or displace the light collection part from the front side of the light transmission unit.

4. The apparatus of claim 1, further comprising a rotating unit configured to rotate the light collection part in the horizontal direction.

5. The apparatus of claim 4, wherein the analysis unit is configured to analyze a plasma state for each of rotational angles of the light collection part.

6. The apparatus of claim 1, wherein the light collection part comprises a plurality of light collectors having different light incident angle ranges corresponding to different sizes of a plurality of substrates, and

the apparatus further comprises a driving unit configured to move the light collector, which has a light incident angle range corresponding to the size of the substrate disposed in the plasma process chamber, of the plurality of light collectors to a front side of the light transmission unit.

7. The apparatus of claim 1, wherein the light collection unit comprises a plurality of light collection parts that are disposed at positions different from each other in the plasma process chamber, and

the plurality of light collection parts have light incident angle ranges corresponding to different sizes of substrates.

8. The apparatus of claim 1, wherein the concave lens is configured to expand the incident angle range of light generated directly above the surface of the substrate.

9. An apparatus for optical emission spectroscopy, comprising:

a light collection unit configured to collect light within a plasma process chamber in which plasma is generated to process a substrate, the light collection unit comprising a concave lens; and

a light transmission unit configured to transmit the collected light to an analysis unit configured to analyze a plasma state,

wherein the light collection unit comprises a light collection part configured to concentrate the light generated in the plasma process chamber and provide the concentrated light to the light transmission unit,

wherein the concave lens is configured to expand an incident angle range of light that is incident from the inside of the plasma process chamber to concentrate the light,

wherein both front surface of the concave lens facing the plasma process chamber and rear surface opposite to the front surface of the concave lens are concave,

wherein the concave lens has a structure in which a curvature thereof in a horizontal direction is greater than that thereof in a vertical direction,

wherein the concave lens has a front surface concave transverse section, a rear surface concave transverse section, and a rectangular vertical section,

wherein the rear surface concave transverse section of the concave lens is concave in the horizontal direction opposite to the curvature of the front surface concave transverse section of the concave lens,

wherein the horizontal direction is parallel to a top surface of the substrate, and the vertical direction is perpendicular to the top surface of the substrate, and

wherein a cross-section of the concave lens that is parallel to the top surface of the substrate is curved, and a cross-section of the concave lens that is perpendicular to the top surface of the substrate is not curved.

10. The apparatus of claim 9, wherein the concave lens is configured to expand the incident angle range of light generated directly above the surface of the substrate.

11. A plasma processing apparatus comprising:

a plasma process chamber in which plasma is generated to process a substrate;

a light collection unit configured to collect light within the plasma process chamber; and

a light transmission unit configured to transmit the collected light to an analysis unit configured to analyze a plasma state,

wherein the light collection unit comprises a concave lens configured to concentrate the light generated in the plasma process chamber and provide the concentrated light to the light transmission unit,

wherein the concave lens is configured to expand an incident angle range of light that is incident from the inside of the plasma process chamber to concentrate the light

wherein both front surface of the concave lens facing the plasma process chamber and rear surface opposite to the front surface of the concave lens are concave,

wherein the concave lens has a structure in which a curvature thereof in a horizontal direction is greater than that thereof in a vertical direction,

wherein the concave lens has a front surface concave transverse section, a rear surface concave transverse section, and a rectangular vertical section,

wherein the rear surface concave transverse section of the concave lens is concave in the horizontal direction opposite to the curvature of the front surface concave transverse section of the concave lens,

wherein the horizontal direction is parallel to a top surface of the substrate, and the vertical direction is perpendicular to the top surface of the substrate, and

wherein a cross-section of the concave lens that is parallel to the top surface of the substrate is curved, and a cross-section of the concave lens that is perpendicular to the top surface of the substrate is not curved.

12. The plasma processing apparatus of claim 11, wherein the concave lens is configured to expand the incident angle range of light generated directly above the surface of the substrate.