Process integration of electrical thickness measurement of gate oxide and tunnel oxides by corona discharge technique

• US 6,593,748 B1
• Filed: 07/12/2001
• Issued: 07/15/2003
• Est. Priority Date: 07/12/2001
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Subramanian, Ramkumar, Singh, Bhanwar, Halliyal, Arvind
• Primary Examiner(s): Patidar, Jay
• Assistant Examiner(s): Nguyen, Vincent Q.
• Application Number:
  US09/904,367
• Time in Patent Office: 733 Days
• Field of Search: 438/14, 438/798, 250/492.2, 324/765, 324/750, 324/759, 324/760, 324/455, 324/766, 324/702, 427/352, 427/355, 427/460
• US Class Current: 324/455
• CPC Class Codes: C23C 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence

Abstract

The present invention relates to a system for controlling a thin film formation process using a corona discharge measurement technique. The system includes a thin film formation system operative to form a thin film based on one or more process parameters, a corona discharge measurement system operable to measure one or more properties of the thin film, and a processor operatively coupled to the thin film formation system and the corona discharge measurement system, wherein the processor analyzes the data from the corona discharge measurement system and a set of target data and controls the one or more process parameters via the thin film formation system based on the analysis. The present invention also relates to a method for controlling a thin film formation using a corona discharge technique. The method includes forming a thin film based on one or more thin film formation process parameters, measuring the thin film via a corona discharge technique, analyzing the results of the corona discharge measurement, and controlling the one or more thin film formation process parameters based on the analysis.

Claims

1. A system for controlling thin film formation, comprising:

a thin film formation system operative to form a thin film on a substrate based on one or more process parameters;

a corona discharge measurement system operative to measure one or more properties of the thin film, thereby defining measured thin film data; and

a processor operatively coupled to the thin film formation system and the corona discharge measurement system, wherein the processor is adapted to receive the measured thin film data from the corona discharge measurement system, and use the measured thin film data to control the one or more process parameters utilized by the thin film formation system.

2. The system of claim 1, wherein the control is based on an analysis of the measured thin film data and a target thin film data set.

3. The system of claim 1, wherein the processor comprises an intelligent system.

4. The system of claim 3, wherein the intelligent system comprises a neural network trained to determine the control of the one or more process parameters based at least on an analysis of the measured thin film data.

5. The system of claim 3, wherein the intelligent system comprises an algorithm designed to determine the control of the one or more thin film process parameters based at least on an analysis of the measured thin film data.

6. The system of claim 1, wherein the processor comprises a look-up table designed to associate the control of the one or more thin film process parameters based at least on an analysis of the measured thin film data.

7. The system of claim 1, wherein the thin film is formed via the thin film formation system in a process chamber and measured via the corona discharge measurement system in a measurement chamber.

8. The system of claim 7, wherein the process chamber and the measurement chamber are operably connected via a substrate transfer system, wherein the substrate transfer system is operable to facilitate a transfer of the substrate between the process chamber and the measurement chamber in an environmentally isolated manner.

9. The system of claim 7, further comprising:

a plurality of process chambers wherein a thin film is formed on a substrate in each of the process chambers; and

a transfer system operable to transfer a substrate between at least one of the process chambers and the measurement chamber in an environmentally isolated manner.

10. The system of claim 9, wherein the processor is operable to control the one or more process parameters for each of the plurality of process chambers based at least on the analysis of the respective measured thin film data.

11. The system of claim 7, wherein the process chamber and the measurement chamber are the same chamber.

12. The system of claim 7, wherein the process chamber is a chemical vapor deposition chamber, atomic layer chemical vapor deposition system, metal organic chemical vapor deposition system, oxide deposition system, nitride deposition system, metal oxide deposition system, silicate deposition system, or aluminate deposition system.

13. The system of claim 7, wherein the process chamber is a rapid thermal processing chamber.

14. The system of claim 1, wherein the one or more process parameters is selected from the group consisting of temperature, pressure, gas flow rate, and formation time.

15. The system of claim 1, wherein the measured thin film data and the target thin film data set comprise thin film electrical thickness data (T_ox).

16. The system of claim 1, wherein the measured thin film data and the target thin film data set comprise thin interface charge density (D_it), total oxide charge (Q_tot), flat band voltage (V_fb), or onset of oxide tunneling (E_tunnel).

17. A method for controlling a thin film formation process comprising:

forming a thin film on a substrate via a thin film formation system based on one or more process parameters;

measuring the thin film using a corona discharge technique, thereby defining measured thin film data;

transmitting the measured thin film data to a processor;

analyzing the measured thin film data via the processor, thereby generating one or more controlled process parameters;

transmitting the one or more controlled process parameters to the thin film formation system via the processor; and

controlling the thin film formation system based on the one or more controlled process parameters.

18. The method of claim 17, wherein analyzing the measured thin film data further comprises analyzing a set of target thin film data via the processor.

19. The method of claim 17, wherein analyzing the measured thin film data further comprises utilizing an intelligent system.

20. The method of claim 19, wherein utilizing the intelligent system further comprises utilizing a neural network trained to generate the one or more controlled process parameters.

21. The method of claim 19, wherein utilizing the intelligent system further comprises utilizing an algorithm designed to generate the one or more controlled process parameters.

22. The method of claim 17, wherein analyzing the measured thin film data further comprises utilizing a look-up table designed to associate the one or more controlled process parameters.

23. The method of claim 17, wherein forming the thin film is performed in a process chamber, and wherein measuring the thin film is performed in a measurement chamber.

24. The method of claim 23, further comprising transferring the substrate between the process chamber and the measurement chamber in an environmentally isolated manner.

25. The method of claim 17, wherein forming the thin film and measuring the thin film is performed in the same chamber.

26. The method of claim 17, wherein forming the thin film is performed iusingchemical vapor deposition.

27. The method of claim 17, wherein forming the thin film is performed using rapid thermal processing.

28. The method of claim 17, wherein the thin film comprises a material selected from the group consisting of an oxide, a nitride, and a high-K dielectric material.

29. The method of claim 17, wherein the thin film is formed on a silicon substrate.

30. The method of claim 17, wherein the thin film is formed on another thin film, thereby defining a stacked thin film.

31. The method of claim 17, wherein the one or more process parameters are selected from a group consisting of temperature, pressure, gas flow rate, and deposition time.

32. The method of claim 17, wherein the measured thin film data and the target thin film data comprise electrical thickness data.

33. The method of claim 17, wherein the measured thin film data and the target thin film data comprise interface charge density data.

34. A method for controlling a stacked thin film formation process in n process chambers, wherein n is an integer greater than one, comprising:

(a) forming a thin film on a substrate in a process chamber via a thin film formation system based on one or more process parameters for the process chamber;

(b) transferring the substrate to a measurement chamber in an environmentally isolated manner;

(c) measuring the thin film using a corona discharge technique, thereby defining measured thin film data for the substrate;

(d) transmitting the measured thin film data to a processor;

(e) analyzing the measured thin film data via the processor, thereby generating one or more controlled process parameters for the process chamber;

(f) transmitting the one or more controlled process parameters for the process chamber to the thin film formation system via the processor;

(g) controlling the thin film formation system based on the one or more controlled process parameters for the process chamber;

(h) determining whether n process chambers have formed a thin film on the substrate and transferring the substrate to another process chamber in an environmentally isolated manner if n process chambers have not formed a thin film on the substrate; and

(i) repeating steps (a) through (h) for n process chambers for the substrate, thereby defining a stacked thin film on the substrate comprising n thin film layers.

35. The method of claim 34, wherein analyzing the measured thin film data further comprises analyzing a set of target thin film data via the processor to control the one or more process parameters.

36. The method of claim 34, wherein analyzing the measured thin film data further comprises utilizing an intelligent system.

37. The method of claim 36, wherein utilizing the intelligent system further comprises utilizing a neural network trained to control the one or more process parameters.

38. The method of claim 36, wherein utilizing the intelligent system further comprises utilizing an algorithm designed to control the one or more process parameters.

39. The method of claim 34, wherein analyzing the measured thin film data further comprises utilizing a look-up table designed to associate the control of the one or more process parameters.

40. The method of claim 34, wherein steps (a) through (h) are performed for a calibration of a thin film formation process on a periodic basis, wherein the one or more controlled process parameters for each process chamber are utilized for the formation of stacked thin films for production substrates.

41. The method of claim 40, further comprising n substrates, wherein each process chamber contains a separate substrate.

42. The method of claim 41, further comprising measuring the thin film on a substrate in the measurement chamber concurrent to forming thin films on substrates in the remaining process chambers.

43. The method of claim 34, wherein forming the thin film is performed using chemical vapor deposition.

44. The method of claim 34, wherein forming the thin film is performed using rapid thermal processing.

45. The method of claim 34, wherein the thin film comprises a material selected from the group consisting of an oxide, a nitride, and a high-K dielectric material.

46. The method of claim 34, wherein the thin film is formed on a silicon substrate.

47. The method of claim 34, wherein the one or more process parameters are selected from a group consisting of temperature, pressure, gas flow rate, and deposition time.

48. The method of claim 34, wherein the measured thin film data and the target thin film data comprise electrical thickness data.

49. The method of claim 34, wherein the measured thin film data and the target thin film data comprise interface charge density data.