Probe station having multiple enclosures

Details Probe station having multiple enclosures Probe station having multiple enclosures

2001-07-17

2002-03-26

Metjahic, Safet (Department: 2858)

Electricity: measuring and testing

Fault detecting in electric circuits and of electric components

Of individual circuit component or element

C324S1540PB, C324S761010

Reexamination Certificate

active

06362636

ABSTRACT:

BACKGROUND OF THE INVENTION
The present invention relates to probe stations, commonly known as package or wafer probers, used manually, semiautomatically or fully automatically to test semiconductor devices. More particularly, the invention relates to such probe stations having EMI shielded enclosures for substantially enclosing the test devices, such as those probe stations shown in commonly-owned U.S. Pat. Nos. 5,266,889 and 5,457,398 which are hereby incorporated by reference.
The probe stations shown in the foregoing patents are capable of performing both low-current and high-frequency measurements within a single shielded enclosure. However, as electrical test currents decrease, or as electrical test frequencies increase, the use of merely a single EMI shielding enclosure becomes less adequate. In the most sensitive of measurements, and particularly (although not necessarily) when guarding is employed for low current measurements as described in U.S. Pat. No. 5,457,398, the choice of the shield potential is critical. Reflecting such criticality, the single shield enclosures shown in the foregoing patents have in the past been equipped with selective connectors enabling the shield potential to match that of the measurement instrumentation ground while being isolated from other connectors, or alternatively to be biased by another connector, or to be connected to AC earth ground. Usually the measurement instrumentation ground is preferred since it provides a “quiet” shield ideally having no electrical noise relative to the measurement instrument. However, if the shielding enclosure is exposed to EMI (such as electrostatic noise currents from its external environment), its ideal “quiet” condition is not achieved, resulting in unwanted spurious currents in the chuck assembly guard element and/or the supporting element for the test device. The effect of such currents is particularly harmful to the operation of the guard element, where the spurious currents result in guard potential errors causing leakage currents and resultant signal errors in the chuck element which supports the test device.
For high-frequency measurements, guarding is typically not employed. However, for the most sensitive of measurements, the “quietness” of the shield is still critical. For this reason, it is common practice to construct a fully shielded room, commonly known as a screen room, large enough to contain a probe station with its own separate shield enclosure, test equipment, and several operators. However, screen rooms take up a large amount of space, are expensive to build, and are ineffective with respect to noise sources within the room.
The environmental influences which ordinarily compromise the desired quiet condition of a shield are the motion of external objects at constant potential which cause spurious shield currents due to varying capacitance, and external AC voltages which cause spurious shield currents via constant capacitance. For sensitive measurements, what is needed is a truly quiet shield unaffected by such environmental influences.
Also, to reduce the need for a screen room, and provide a shield unaffected by closely adjacent environmental influences, such quiet shield structure should be compact.
BRIEF SUMMARY OF THE INVENTION
The present invention satisfies the foregoing need by providing a probe station having respective inner and outer conductive shield enclosures insulated from each other, both enclosures at least partially enclosing the chuck assembly element which supports the test device, and also its associated guard element if one is provided. The outer shield enclosure, which is preferably connected either directly or indirectly to AC earth ground, intercepts the external environmental noise, minimizing its effects on the inner shield and on the chuck assembly elements enclosed by the inner shield.
Such inner and outer shield enclosures are preferably built integrally into the probe station and therefore are compact.
The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description, taken in conjunction with the accompanying drawings.


REFERENCES:
patent: 3185927 (1965-05-01), Margulis et al.
patent: 3333274 (1967-07-01), Forcier
patent: 3405361 (1968-10-01), Kattner et al.
patent: 3710251 (1973-01-01), Hagge et al.
patent: 4115736 (1978-09-01), Tracy
patent: 4383178 (1983-05-01), Shibata et al.
patent: 4694245 (1987-09-01), Frommes
patent: 4731577 (1988-03-01), Logan
patent: 4755746 (1988-07-01), Mallory et al.
patent: 4757255 (1988-07-01), Margozzi
patent: 4758785 (1988-07-01), Rath
patent: 4771234 (1988-09-01), Cook et al.
patent: 4845426 (1989-07-01), Nolan et al.
patent: 4856904 (1989-08-01), Akagawa
patent: 4884026 (1989-11-01), Hayakawa et al.
patent: 5077523 (1991-12-01), Blanz
patent: 5084671 (1992-01-01), Miyata et al.
patent: 5220277 (1993-06-01), Reitinger
patent: 5266889 (1993-11-01), Harwood et al.
patent: 5345170 (1994-09-01), Schwindt et al.
patent: 5457398 (1995-10-01), Schwindt et al.
patent: 5963027 (1999-10-01), Peters
patent: 6002263 (1999-12-01), Peters et al.
patent: 3114466 (1982-03-01), None
patent: 201205 (1986-12-01), None
patent: 1-209380 (1989-08-01), None
patent: 2-022837 (1990-01-01), None
patent: 2-220453 (1990-09-01), None
patent: 4-000732 (1992-01-01), None
“Model TPO3000 Series Thermochuck® Systems,” four-page product note, Temptronic Corporation, Newton, MA (May 1992 or earlier).
“Application Note 1 Controlled Environment Enclosure,” two-page application note, Temptronic Corporation, Newton, MA (May 1992 or earlier).
“Cross Section Signatone S-1240,” one-page sketch prepared by Signatone counsel, Signatone, San Jose, CA (Feb. 1988 or earlier per Signatone).
“S-1240,” two-page product note, Signatone, San Jose, CA (Feb. 1988 or earlier per Signatone counsel).
Y. Yamamoto, “A Compact Self-Shielding Prober . . . ,” IEEE Trans., Inst. and Meas., vol. 38, pp 1088-1093, 1989.
Temptronic's “Guarded” Chuck, one-page note describing guarding system of Temptronic Corporation of Newton, MA, dated Nov. 15, 1989.
Beck & Tomann, “Chip Tester,” IBM Technical Disclosure Bulletin, p. 4819 (Jan. 1985).
Article by William Knauer entitled “Fixturing for Low-Current/Low Voltage Parametric Testing,” appearing in Evaluation Engineering, (1990) pp. 150-153.
Hewlett-Packard, “Application Note 356-HP 4142 B Modular DC Source/Monitor Practical Applications,” (Nov. 1987) pp. 1-4.
Hewlett-Packard, H-P Model 4284A Precision LCR Meter, Operation Manual (Dec. 1991) pp. 2-1, 6-9 and 6-15.
Cascade Microtech, Advanced On-Wafer Device Characterization Using the Summit 10500, (Dec. 1992)
Micromanipulator Company, Inc., “Test Station Accessories,” 1983. (month unavailable).
Micromanipulator Company, Inc., “Model 8000 Test Station,” 1986. (month unavailable).
Micromanipulator Company, Inc., “Model 8000 Test Station,” 1988. (month unavailable).
Micromanipulator Company, Inc., “Probing Stations and Accessories,” 1995, pp. 1-12.
Photograph of Micromanipulator Probe Station, 1994.
Applebay, Harry F., Deposition transcript (pp. 61-67) with Exhibits 581 A,B,C describing Flexion AP-1 probe station sold in 1987.

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