CALIBRATION STANDARDS AND METHODS OF THEIR FABRICATION AND USE

• US 20110208467A1
• Filed: 02/23/2010
• Published: 08/25/2011
• Est. Priority Date: 02/23/2010
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: Tang, Jinbang
• Granted Patent: US 8,290,736 B2
• Time in Patent Office: Days
• US Class Current: 702/117
• CPC Class Codes: G01R 27/28 Measuring attenuation, gain, phase shift or derived characteristics of electric four pole networks, i.e. two-port networks; Measuring transient response in line transmission systems H04B3/46
• CPC Class Codes: G01R 35/007 Standards or reference devices, e.g. voltage or resistance standards, "golden references"
• 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 2924/14 Integrated circuits

Abstract

An embodiment of a calibration standard includes a substrate, a set of conductive structures fabricated on the substrate, and a conductive end structure fabricated on the substrate. The set of conductive structures include an inner conductive structure, a first outer conductive structure positioned to one side of the inner conductive structure, and a second outer conductive structure positioned to an opposite side of the inner conductive structure. The inner and outer conductive structures are aligned in parallel with each other along offset principal axes of the inner and outer conductive structures. The conductive end structure is electrically connected between an end of the first outer conductive structure and an end of the second outer conductive structure, and the conductive end structure is spatially separated from an end of the inner conductive structure at the surface of the substrate.

Claims

1. A set of calibration standards comprising:

a substrate having a surface;

a first set of first conductive structures fabricated on the surface of the substrate, wherein the first conductive structures include a first inner conductive structure, a first outer conductive structure positioned to one side of the first inner conductive structure, and a second outer conductive structure positioned to an opposite side of the first inner conductive structure, and wherein the first conductive structures are aligned in parallel with each other along offset principal axes of the first conductive structures; and

a first conductive end structure electrically connected between a first end of the first outer conductive structure and a first end of the second outer conductive structure, wherein the first conductive end structure is spatially separated from a first end of the first inner conductive structure at the surface of the substrate.

2. The set of calibration standards of claim 1, wherein the set of calibration standards further comprise:

a second conductive end structure electrically connected between a second end of the first outer conductive structure and a second end of the second outer conductive structure, wherein the second conductive end structure is spatially separated from a second end of the first inner conductive structure at the surface of the substrate, and

wherein the first inner conductive structure is electrically isolated from the first and second conductive end structures.

3. The set of calibration standards of claim 2, wherein the first set of first conductive structures, the first conductive end structure, and the second conductive end structure form portions of a thru-type calibration standard.

4. The set of calibration standards of claim 2, wherein the first set of first conductive structures, the first conductive end structure, and the second conductive end structure form portions of a line-type calibration standard.

5. The set of calibration standards of claim 1, further comprising:

a second conductive end structure electrically connected between a second end of the first outer conductive structure and a second end of the second outer conductive structure, wherein the second conductive end structure is spatially separated from a second end of the first inner conductive structure at the surface of the substrate, and

wherein the first set of first conductive structures are electrically connected between the first ends and the second ends of the first inner conductive structure and the first and second conductive end structures, and

wherein the first set of first conductive structures, the first conductive end structure, and the second conductive end structure form portions of a short-type calibration standard.

6. The set of calibration standards of claim 1, further comprising:

a second set of second conductive structures fabricated on the surface of the substrate, wherein the second conductive structures include a second inner conductive structure, a third outer conductive structure positioned to one side of the second inner conductive structure, and a fourth outer conductive structure positioned to an opposite side of the second inner conductive structure, and wherein the second conductive structures are aligned in parallel with each other and along the principal axes of the first conductive structures, and wherein the first conductive structures are spatially separated from the second conductive structures at the surface of the substrate; and

a second conductive end structure electrically connected between a first end of the third outer conductive structure and a first end of the fourth outer conductive structure, wherein the second conductive end structure is spatially separated from a first end of the second inner conductive structure at the surface of the substrate.

7. The set of calibration standards of claim 6, wherein the first set of first conductive structures, the second set of second conductive structures, the first conductive end structure, and the second conductive end structure form portions of an open-type calibration standard.

8. The set of calibration standards of claim 6, further comprising:

resistive loads electrically connected between the first inner conductive structure and each of the first and second outer conductive structures, and between the second inner conductive structure and each of the third and fourth outer conductive structures,

wherein the first set of first conductive structures, the second set of second conductive structures, the first conductive end structure, the second conductive end structure, and the resistive loads form portions of a load-type calibration standard.

9. The set of calibration standards of claim 1, further comprising:

one or more conductive vias formed in the substrate between the first conductive end structure and a ground structure.

10. The set of calibration standards of claim 1, wherein the first conductive end structure is integrally formed with the first and second outer conductive structures from a same material as the first and second outer conductive structures.

11. The set of calibration standards of claim 1, wherein a width of a portion of the first conductive end structure that is connected to the first outer conductive structure is equal to a width of the first end of the first outer conductive structure.

12. The set of calibration standards of claim 1, wherein a width of a portion of the first conductive end structure that is connected to the first outer conductive structure is less than a width of the first end of the first outer conductive structure.

13. The set of calibration standards of claim 1, wherein the substrate is a wafer on which a device to be tested is fabricated.

14. The set of calibration standards of claim 1, wherein the substrate is a substrate that is separate from a device to be tested.

15. A method for fabricating a set of calibration standards, the method comprising the steps of:

providing a substrate having a surface;

forming a first set of first conductive structures on the surface of the substrate, wherein the first conductive structures include a first inner conductive structure, a first outer conductive structure positioned to one side of the first inner conductive structure, and a second outer conductive structure positioned to an opposite side of the first inner conductive structure, and wherein the first conductive structures are aligned in parallel with each other along offset principal axes of the first conductive structures; and

forming a first conductive end structure on the surface of the substrate and electrically connected between a first end of the first outer conductive structure and a first end of the second outer conductive structure, wherein the first conductive end structure is spatially separated from a first end of the first inner conductive structure at the surface of the substrate.

16. The method of claim 15, further comprising:

forming a second conductive end structure on the surface of the substrate and electrically connected between a second end of the first outer conductive structure and a second end of the second outer conductive structure, wherein the second conductive end structure is spatially separated from a second end of the first inner conductive structure at the surface of the substrate, and

wherein the first set of first conductive structures, the first conductive end structure, and the second conductive end structure form portions of a type of calibration standard selected from a group of calibration standards consisting of a thru-type calibration standard, a line-type calibration standard, and a short type calibration standard.

17. The method of claim 15, further comprising:

forming a second set of second conductive structures on the surface of the substrate, wherein the second conductive structures include a second inner conductive structure, a third outer conductive structure positioned to one side of the second inner conductive structure, and a fourth outer conductive structure positioned to an opposite side of the second inner conductive structure, and wherein the second conductive structures are aligned in parallel with each other and along the principal axes of the first conductive structures, and wherein the first conductive structures are spatially separated from the second conductive structures at the surface of the substrate; and

forming a second conductive end structure on the surface of the substrate and electrically connected between a first end of the third outer conductive structure and a first end of the fourth outer conductive structure, wherein the second conductive end structure is spatially separated from a first end of the second inner conductive structure at the surface of the substrate, and

wherein the first set of first conductive structures, the second set of second conductive structures, the first conductive end structure, and the second conductive end structure form portions of an open-type calibration standard.

18. The method of claim 15, wherein the substrate includes a ground structure, and the method further comprises:

forming one or more conductive vias in the substrate between the first conductive end structure and the ground structure.

19. The method of claim 15, wherein providing the substrate comprises providing a wafer on which a device to be tested is fabricated.

20. The method of claim 15, wherein providing the substrate comprises providing a substrate that is separate from a device to be tested.

21. A method for using a set of calibration standards with a testing system configured to test electrical characteristics of an integrated circuit device, the method comprising the steps of:

providing a set of calibration standards that includes

a substrate having a surface,

a first set of first conductive structures fabricated on the surface of the substrate, wherein the first conductive structures include a first inner conductive structure, a first outer conductive structure positioned to one side of the first inner conductive structure, and a second outer conductive structure positioned to an opposite side of the first inner conductive structure, and wherein the first conductive structures are aligned in parallel with each other along offset principal axes of the first conductive structures, and

a first conductive end structure electrically connected between a first end of the first outer conductive structure and a first end of the second outer conductive structure, wherein the first conductive end structure is spatially separated from a first end of the first inner conductive structure at the surface of the substrate;

contacting probes of the testing system with probe contact areas of the first conductive structures;

providing excitation signals through the probes;

measuring responsive signals through the probes; and

analyzing the responsive signals to determine electrical characteristics of the testing system.

22. The method of claim 21, further comprising:

generating an error model of the testing system based on the electrical characteristics of the testing system; and

determining electrical parameters of the integrated circuit device using the testing system and based on the error model of the testing system.

23. The method of claim 22, further comprising:

determining whether the electrical parameters of the integrated circuit device compare unfavorably to device specifications.

24. The method of claim 23, further comprising:

when the electrical parameters compare unfavorably to the device specifications, modifying a design of the integrated circuit device.

25. The method of claim 23, further comprising:

when the electrical parameters compare unfavorably to the device specifications, rejecting the integrated circuit device.