Method and apparatus for monitoring integrated circuit fabrication

• US 6,820,028 B2
• Filed: 01/23/2004
• Issued: 11/16/2004
• Est. Priority Date: 11/04/2002
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: Brion Technologies Incorporated (ASML Holding NV)
• Inventors: Ye, Jun, Chen, Xun
• Primary Examiner(s): Hoff, Marc S.
• Assistant Examiner(s): Raymond, Edward
• Application Number:
  US10/763,433
• Publication Number:
  US 20040153279A1
• Time in Patent Office: 298 Days
• Field of Search: 702/116, 702/117, 702/132, 702/136, 702/184, 702/185, 438/5, 438/10, 438/11, 438/14, 438/17, 438/18, 156/345.13
• US Class Current: 702/117
• CPC Class Codes: G01D 9/005 Solid-state data loggers
• CPC Class Codes: H01L 21/67253 Process monitoring, e.g. flow or thickness monitoring
• CPC Class Codes: H01L 21/67276 Production flow monitoring, e.g. for increasing throughput program-control systems per se G05B19/00, e.g. total factory control G05B19/418
• CPC Class Codes: H01L 22/34 Circuits for electrically characterising or monitoring manufacturing processes, e. g. whole test die, wafers filled with test structures, on-board-devices incorporated on each die, process control monitors or pad structures thereof, devices in scribe line switching, multiplexing, gating devices G01R19/25; process control with lithography, e.g. dose control, G03F7/20; structures for alignment control by optical means G03F7/70633
• CPC Class Codes: H01L 2224/48463 the connecting portion on the bonding area of the semiconductor or solid-state body being a ball bond
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/3011 Impedance

Abstract

In one aspect, the present invention is a sensor unit for sensing process parameters of a process to manufacture an integrated circuit using integrated circuit processing equipment. In one embodiment, the sensor unit includes a substrate having a wafer-shaped profile and a first sensor, disposed on or in the substrate, to sample a first process parameter. The sensor unit of this embodiment also includes a second sensor, disposed on or in the substrate, to sample a second process parameter wherein the second process parameter is different from the first process parameter. In one embodiment, the sensor unit includes a first source, disposed on or in the substrate, wherein first source generates an interrogation signal and wherein the first sensor uses the interrogation signal from the first source to sample the first process parameter. The sensor unit may also include a second source, disposed on or in the substrate, wherein second source generates an interrogation signal and wherein the second sensor uses the interrogation signal from the second source to sample the second process parameter. The first sensor and the first source may operate in an end-point mode or in a real-time mode. In this regard, the first sensor samples the first parameter periodically or continuously while the sensor unit is disposed in the integrated circuit processing equipment and undergoing processing. In one embodiment, the first sensor is a temperature sensor and the second sensor is a pressure sensor, a chemical sensor, a surface tension sensor or a surface stress sensor.

Claims

1. An EIW unit for use in measuring a physical characteristic of an electrically conductive layer that is deposited or formed by integrated circuit processing equipment which is used to manufacture an integrated circuit, the EIW unit comprising:

a substrate having a wafer or wafer-like shape and a first surface to receive the conductive layer that is deposited or formed by the integrated circuit processing equipment; and

a sensor structure disposed on or in the substrate, the sensor structure including a plurality of electrodes that are disposed on or in the substrate such that at least a portion of each electrode is exposed on the first surface of substrate wherein each electrode is spatially located, relative to the other electrodes and the conductive layer, on or in the substrate to permit measuring of the physical characteristic of the conductive layer after deposition or formation of the conductive layer on the EIW unit, and wherein the plurality of electrodes, in conjunction with the conductive layer deposited or formed on the first surface of the substrate, form a four-point probe type sensor.

2. The EIW unit of claim 1 further including measurement circuitry, coupled to the sensor structure, to sample the electrical characteristic of the conductive layer.

3. The EIW unit of claim 2 wherein the measurement circuitry is disposed in or on the substrate and includes a current or voltage source which is coupled to the electrodes of the sensor structure.

4. The EIW unit of claim 3 wherein the measurement circuitry further includes a current or voltage measuring circuitry which is coupled to the electrodes of the sensor structure.

5. The EIW unit of claim 2 wherein the measurement circuitry includes data storage to store the sampled electrical characteristic of the conductive layer.

6. The EIW unit of claim 5 wherein the measurement circuitry operates in a real-time mode.

7. The EIW unit of claim 2 further including:

communication circuitry, disposed in or on the substrate, to provide the sampled electrical characteristic of the conductive layer to an external device; and

at least one rechargeable battery, to provid electrical power to the communication circuitry and measurement circuitry.

8. The EIW unit of claim 2 wherein the measurement circuitry operates in an end-point mode.

41. The EIW unit of claim 1 further including:

measurement circuitry, coupled to the sensor structure, to sample the electrical characteristic of the conductive layer while the EIW unit is disposed in the integrated circuit processing equipment and the electrically conductive layer is being deposited or formed; and

at least one battery, disposed on or in the substrate, to provide electrical power to the measurement circuitry.

9. A system for measuring a physical characteristic of a first conductive layer that is deposited or formed by integrated circuit processing equipment which is used to manufacture an integrated circuit, the system comprising;

an EIW unit, including;

a substrate having a wafer or wafer-like shape and a first surface to receive the first conductive layer that is deposited or formed by the integrated circuit processing equipment; and

a first sensor structure disposed on or in the substrate, the first sensor structure including a plurality of electrodes that are disposed on or in the substrate such that at least a portion of each electrode is exposed on the first surface of the substrate wherein each electrode is spatially located, relative to the other electrodes and the first conductive layer, on or in the substrate to permit measuring of the physical characteristic of the first conductive layer after deposition or formation by the integrated circuit processing equipment on the EIW unit, and wherein the plurality of electrodes, in conjunction with the first conductive layer deposited or formed on the first surface of the substrate, form a four-point probe type sensor;

measurement circuitry, coupled to the first sensor structure, to sample an electrical characteristic of the first conductive layer; and

a computing unit, coupled to the measurement circuitry, to receive data which is representative of the electrical characteristic of the first conductive layer and to determine the physical characteristic of the first conductive layer using the received data.

10. The system of claim 9 wherein at least a portion of the measurement circuitry is disposed on or in the substrate of the EIW unit.

11. The system of claim 9 wherein the EIW unit further includes a second sensor structure disposed on or in the substrate, the second sensor structure including a plurality of electrodes that are disposed on or in the substrate such that at least a portion of each electrode is exposed on the first surface of substrate wherein each electrode is spatially located, relative to the other electrodes of the second sensor structure and a second conductive layer, on or in the substrate to permit measuring of a physical characteristic of the second conductive layer after deposition or formation of the second conductive layer by the integrated circuit processing equipment on the EIW unit.

12. The system of claim 11 wherein:

the measurement circuitry is coupled to the second sensor structure to sample an electrical characteristic of the second conductive layer; and

the computing unit rec ives the data which is representative of the electrical characteristic of the s cond conductive layer and, using that data, determines the physical characteristic of the second conductive layer.

13. The system of claim 12 wherein the physical characteristic of the first and second conductive layers are the linewidths of the conductive layers and wherein the computing unit determines a linewidth distribution using the data which is representative of the electrical characteristic of the first conductive layer and the data which is representative of the electrical characteristic of the second conductive layer.

14. The system of claim 9 wherein the measurement circuitry is disposed in or on the substrate and includes a current or voltage source which is coupled to the electrodes of the first sensor structure.

15. The system of claim 14 wherein the measurement circuitry further includes a current or voltage measuring circuitry which is coupled to the electrodes of the first sensor structure.

16. The system of claim 14 wherein th measurement circuitry includes data storage to store data which is representative of the electrical characteristic of the first conductive layer.

17. The system of claim 14 wherein the EIW unit further includes:

communication circuitry, disposed in or on the substrate, to provide the data which is representative of the electrical characteristic of the first conductive layer to the computing unit; and

at least one rechargeable battery, to provide electrical power to the communication circuitry and measurement circuitry.

18. The system of claim 9 wherein the measurement circuitry operates in a real-time mode.

19. The system of claim 9 wherein the measurement circuitry operates in an end-point mode.

20. The system of claim 9 wherein the electrical characteristic includes a sheet resistance of the first conductive layer and wherein the physical characteristic of the first conductive layer is the thickness of the first conductive layer.

21. The system of claim 20 wherein the measurement circuitry periodically samples electrical characteristic of th first conductive lay r during deposition or formation of the first conductive layer by the integrated circuit processing equipment on the first surface of the EIW unit.

22. The system of claim 21 wherein the computing unit receives the periodic samples of the electrical characteristic of the first conductive layer and, in response thereto, calculates the thickness of the first conductive layer over time.

23. The system of claim 22 wherein the periodic samples of the electrical characteristic of the first conductive layer are representative of the entire deposition or formation process.

24. The system of claim 22 wherein the formation process is a polishing process or chemical-mechanical polishing (CMP) process.

42. The system of claim 9 further including:

measurement circuitry, coupled to the first sensor structure, to sample the electrical characteristic of the first conductive layer while the EIW unit is disposed in the integrated circuit processing equipment and the first conductive layer is being deposited or formed; and

at least one battery, disposed on or in the substrate, to provide electrical power to the measurement circuitry.

25. An EIW unit for use in measuring a first parameter of a first conductive layer that is deposited or formed by integrated circuit processing equipment which is used to manufacture an integrated circuit, the EIW unit comprising:

a substrate having a wafer or wafer-like shape and a first surface to receive the first conductive layer that is deposited or formed by the integrated circuit processing equipment; and

a sensor structure disposed on or in the substrate, the sensor structure including;

a plurality of electrodes that are disposed on or in the substrate; and

a base pad electrically connected to the plurality of electrodes and disposed on or in the substrate such that at least a portion of the pad is exposed on the first surface of the substrate, wherein the base pad is spatially located on or in the substrate such that the first conductive layer is deposited or formed on the base pad by the integrated circuit processing equipment, and wherein the plurality of electrodes, base pad and first conductive layer form a four-point probe type sensor.

26. The EIW unit of claim 25 further including measurement circuitry, coupled to the sensor structure, to sample an electrical characteristic of the first conductive layer.

27. The EIW unit of claim 26 wherein the measurement circuitry is disposed in or on the substrate and includes a current or voltage source which is coupled to the electrodes of the sensor structure.

28. The EIW unit of claim 27 wherein th measurement circuitry further includes a current or voltag measuring circuitry which is coupled to the electrodes of the sensor structure.

29. The EIW unit of claim 26 wherein the measurement circuitry includes data storage to store data which is representative of the electrical characteristic of the first conductive layer.

30. The EIW unit of claim 26 wherein the measurement circuitry operates in a real-time mode.

31. The EIW unit of claim 30 further including:

communication circuitry, disposed in or on the substrate, to provide the data which is representative of the electrical characteristic of the first conductive layer to an external device; and

at least one rechargeable battery, to provide electrical power to the communication circuitry and measurement circuitry.

32. The EIW unit of claim 26 wherein the measurement circuitry operates in an end-point mode.

33. The EIW unit of claim 26 further including computing circuitry disposed on or in the substrate and coupled to the measurement circuitry, wherein the computing circuitry determines the first parameter of the first conductive layer using the electrical characteristic of the first conductive layer.

34. The EIW unit of claim 33 wherein the first parameter is the linewidth of the first conductive layer.

35. The EIW unit of claim 26 wherein the electrical characteristic includes the resistivity of the first conductive layer.

36. The EIW unit of claim 35 further including computing circuitry, coupled to the measurement circuitry, to determine the first parameter using resistivity of the first conductive layer.

37. The EIW unit of claim 36 wherein the first parameter is the thickness of the first conductive layer.

38. The EIW unit of claim 26 wherein the measurement circuitry periodically samples an electrical characteristic of the first conductive layer during deposition or formation of the first conductive layer on the first surface of the EIW unit.

39. The EIW unit of claim 38 wherein the formation process is a polishing process.

40. The EIW unit of claim 39 wherein the polishing process is a chemical-mechanical polishing (CMP) process.

43. Th EIW unit of claim 25 further including:

measurement circuitry, coupl d to the sensor structure, to sample an lectrical characteristic of the first conductive layer while the EIW unit is disposed in the integrated circuit processing equipment and the first conductive layer is being deposited or formed; and

at least one battery, disposed on or in the substrate, to provide electrical power to the measurement circuitry.