Real-time system for monitoring and controlling film uniformity and method of applying the same

• US 7,436,526 B2
• Filed: 01/31/2007
• Issued: 10/14/2008
• Est. Priority Date: 11/21/2006
• Status: Active Grant

• Current Assignee: ProMOS Technologies, Inc.
• Original Assignee: ProMOS Technologies, Inc.
• Inventors: Tsai, Yu-Min, Wu, Hsiao-Che, Tsai, Wen-Li
• Primary Examiner(s): Lauchman, L. G.
• Assistant Examiner(s): Underwood, Jarreas C
• Application Number:
  US11/669,165
• Publication Number:
  US 20080118631A1
• Time in Patent Office: 622 Days
• Field of Search: 156/64, 356600-640, 427/248.1
• US Class Current: 356/630
• CPC Class Codes: C23C 14/544 using measurement in the gas phase
• CPC Class Codes: G01B 11/0625 with measurement of absorption or reflection
• CPC Class Codes: G01B 11/0675 using interferometry
• CPC Class Codes: G01B 11/0683 measurement during deposition or removal of the layer
• CPC Class Codes: H01L 22/12 for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions electrical measurement of diffusions H01L22/14
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps

Abstract

A real-time system adapted to a PVD apparatus for monitoring and controlling film uniformity is described. The system includes a shielding plate, a monitoring device, and a data processing program. The shielding plate is disposed on an inner wall of a reaction chamber above a wafer stage. An opening in the center of the shielding plate exposes the wafer. The monitoring device including a scanner and a sensor respectively disposed on opposite sidewalls of the reaction chamber between the shielding plate and the wafer stage is used for measuring the flux of the particles on every portion of the wafer to acquire real-time uniformity data including a function of the wafer position and the flux. The data processing program compares the real-time uniformity data and reference uniformity data, and a feedback signal is outputted to the PVD apparatus to adjust the process parameter thereof for controlling film uniformity.

Claims

1. A real-time system for monitoring and controlling film uniformity, the system being adapted to a physical vapor deposition (PVD) apparatus including a reaction chamber and a wafer stage used to carry a wafer, the system comprising:

a shielding plate, disposed on an inner wall of the reaction chamber above the wafer stage, wherein an opening in the center of the shielding plate exposes the wafer, and particles generated by the PVD apparatus pass through the opening and form a film on the wafer;

a monitoring device, including a scanner and a sensor which are disposed on opposite sidewalls of the reaction chamber between the shielding plate and the wafer stage, the monitoring device being used to measure the flux of the particles on every portion of the wafer so as to acquire real-time uniformity data including a function of the wafer position and the flux; and

a data processing program for comparing the real-time uniformity data and reference uniformity data and outputting a feedback signal to the PVD apparatus to adjust the process parameter thereof.

2. The real-time system for monitoring and controlling film uniformity as claimed in claim 1, wherein the sensor detects absorption of the particles such that the flux is measured.

3. The real-time system for monitoring and controlling film uniformity as claimed in claim 2, wherein the real-time uniformity data comprise a function of the wafer position and the absorption.

4. The real-time system for monitoring and controlling film uniformity as claimed in claim 1, wherein the scanner moves along a horizontal direction parallel to the wafer surface.

5. The real-time system for monitoring and controlling film uniformity as claimed in claim 1, wherein the scanner comprises an array light source.

6. The real-time system for monitoring and controlling film uniformity as claimed in claim 1, wherein the monitoring device is arranged in a two-dimensional array and is disposed on a horizontal surface parallel to the wafer surface.

7. The real-time system for monitoring and controlling film uniformity as claimed in claim 1, wherein the scanner outputs a collimated ray beam.

8. The real-time system for monitoring and controlling film uniformity as claimed in claim 1, wherein the shielding plate shields the particles which are not deposited on the wafer.

9. The real-time system for monitoring and controlling film uniformity as claimed in claim 1, wherein the PVD apparatus comprises a double-ring electromagnetic controlling system.

10. The real-time system for monitoring and controlling film uniformity as claimed in claim 1, wherein the PVD apparatus comprises a magnetic coil.

11. A method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 1, the method being adapted to the PVD process, the method comprising:

synchronically measuring the flux of the particles on every portion of the wafer with use of the real-time system for monitoring and controlling film uniformity and obtaining the real-time uniformity data;

executing the data processing program for comparing the real-time uniformity data and the reference uniformity data; and

outputting the feedback signal to the PVD apparatus to adjust the process parameter thereof.

12. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 11, wherein the method of measuring the flux of the particles comprises:

outputting a ray beam passing through the particles from the scanner; and

detecting the absorption of the particles from the sensor to measure the flux.

13. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 12, wherein the real-time uniformity data comprise the function of the wafer position and the absorption.

14. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 11, further comprising initiating a relative motion between the scanner and the wafer along a horizontal direction, the horizontal direction being parallel to the wafer surface.

15. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 11, wherein the scanner comprises an array light source.

16. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 11, wherein the monitoring device is arranged in a two-dimensional array and is disposed on a horizontal surface parallel to the wafer surface.

17. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 11, wherein the scanner outputs a collimated ray beam.

18. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 11, wherein the shielding plate shields the particles which are not deposited on the wafer during the PVD process.

19. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 11, wherein the PVD apparatus comprises a double-ring electromagnetic controlling system.

20. The method of applying the real-time system for monitoring and controlling film uniformity as claimed in claim 11, wherein the process parameter of the PVD apparatus is adjusted so as to adjust the flux of the particles on every portion of the wafer.