Test assembly and method of assembling the test assembly for a test period

Abstract

The present disclosure generally relates to test equipment, apparatus and systems for devices under test (such as but not limited to semiconductor devices). More specifically, the present disclosure relates to portable test equipment, apparatus and systems for use in atypical test environments.

Description

Technical Field

[0001] The present disclosure generally relates to test equipment, apparatus and systems for devices under test, such as but not limited to semiconductor devices. More specifically, the present disclosure relates to portable test equipment, apparatus and systems for use in atypical test environments. Background Art

[0002] The semiconductor industry continues to require access to the many electronic devices on semiconductor wafers. As the semiconductor industry grows and devices become smaller and more complex, many electronic devices, most commonly the semiconductor devices and the electrical interconnects on the wafer, must be electrically tested, for example, for leakage current and very low operating currents while the device is in wafer form. In addition, current and device characteristics often need to be evaluated over a wide temperature and voltage range to understand how temperature and voltage affect the device. Furthermore, due to the continued rapid changes in semiconductor technology, the size of semiconductor devices and their electrical contact pads are getting smaller and smaller.

[0003] To effectively measure semiconductor devices in wafer form, probes are used to contact conductive pads on the surface of the wafer. These probes are in turn electrically connected to the test instrument. Typically, additional electrical interconnect components (such as circuit boards) form part of the connection between the probes and the test instrument. To minimize degradation of electrical measurements, the probes and interconnect components must be designed to isolate the measurement signal from external electrical interference, leakage currents through dielectric materials, parasitic capacitance, triboelectric noise, piezoelectric noise, and dielectric absorption.

[0004] Therefore, there is a continuing need for improvements in semiconductor test equipment used to electrically probe semiconductor devices, such as semiconductor wafers. Summary of the invention

[0005] The present disclosure generally relates to test equipment, apparatus and systems for devices under test, such as but not limited to semiconductor devices. More specifically, the present disclosure relates to portable test equipment, apparatus and systems for use in atypical test environments.

[0006] In one embodiment, a test assembly for testing a device under test comprises: a base plate including a test site, a top plate, and a probe card, wherein the probe card is fixed to the top plate and extends through the top plate to contact the device under test set on the test site. The base plate includes a flexible ring, a socket set in the flexible ring, and a hole. The test site is set within the periphery of the flexible ring, and the test site is configured to support the device under test. The top plate includes an adjustable rigid stop and a pin. A fastener is configured to be inserted through the adjustable rigid stop and aligned with the hole to provide Z positioning and control. The pins can be inserted into the socket, and when inserted, the pins and the socket provide X and Y control. The flexible ring is configured to provide Z positioning and control. The probe card is configured to push the device under test against the base plate.

[0007] In one embodiment, the pin is tapered.

[0008] In one embodiment, the pin is configured to provide rotational positioning and control.

[0009] In one embodiment, the test assembly further comprises a cleaning plate and a cleaning pad.

[0010] In one embodiment, the cleaning plate includes a flexible ring, and the cleaning pad is within a perimeter of the flexible ring of the cleaning plate.

[0011] In one embodiment, the cleaning pad comprises tungsten carbide.

[0012] In one embodiment, the test site includes a rigid site stop and a flexible holder to allow the device under test to remain in place at the test site.

[0013] In one embodiment, the base plate includes a pad configured to receive the adjustable rigid stop.

[0014] In one embodiment, the top plate includes an adjustable lock configured to secure the rigid stop in a desired position in the Z position.

[0015] In one embodiment, a method of assembling a test assembly for a device under test includes: assembling the test assembly by mounting the top plate including the probe card onto the bottom plate; and tightening a fastener to fix the test assembly.

[0016] BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Reference is made to the accompanying drawings which form a part of this disclosure and which illustrate embodiments in which the systems and methods described in this specification may be practiced.

[0018] Figure 1shows a top perspective view of a probe card assembly according to an embodiment;

[0019] Figure 2 It shows that according to the embodiment Figure 1 A bottom perspective view of a probe card assembly;

[0020] Figure 3 It shows that according to the embodiment Figure 1 a top perspective view of a probe card assembly with the probe card removed;

[0021] Figure 4 It shows that according to the embodiment Figure 1 a top perspective view of a probe card assembly with the probe card removed;

[0022] Figure 5 It shows that according to the embodiment Figure 1 a cross-sectional view of a probe card assembly with the probe card removed;

[0023] Figure 6 It shows that according to the embodiment Figure 1 A side view of a probe card assembly;

[0024] Figure 7 shows a top perspective view of a probe card assembly according to an embodiment;

[0025] Fig. 8A and 8B It shows that according to the embodiment Figure 7 A top view of a base plate of a probe card assembly;

[0026] Fig.9A and 9B The assembly according to the embodiment is shown Figure 7 Method for probe card assembly;

[0027] Fig. 10A and 10B A cleaning plate according to an embodiment is shown, which can be used in an embodiment Figure 7 A probe card assembly;

[0028] Fig. 10C The installation according to the embodiment is shown Figure 7 The probe card assembly Fig. 10A and 10B Cleaning board.

[0029] Like reference numerals refer to like parts throughout. DETAILED DESCRIPTION

[0030] The present disclosure generally relates to test equipment, apparatus and systems for devices under test, such as but not limited to semiconductor devices. More specifically, the present disclosure relates to portable test equipment, apparatus and systems for use in atypical test environments.

[0031] The test apparatus and systems described herein may be particularly suitable for testing devices under test that include atypical test environments. In one embodiment, the atypical test environment may include, but is not limited to, application of extreme temperatures (e.g., cold such as in a cryostat; heat such as in an oven; etc.); application of radiation; application of pressure, etc.

[0032] In one embodiment, the test equipment and systems described herein may be portable such that the test equipment and components may be placed in an atypical test environment and used to test devices (eg, chips) directly in the atypical test environment rather than on a semiconductor wafer.

[0033] In one embodiment, the test apparatus and system described herein are portable, wherein the probe and its mounting piece or plate and the mounting piece or plate of the device under test have motion control in the X, Y and Z directions as well as θ, compared to many current apparatus and systems in which both the probe and the device under test can move, requiring a large additional expense of additional equipment to control or limit the motion. The test apparatus and system described herein are portable because the mounting features provide motion control in a compact set of equipment. The test apparatus and system described herein are portable and can allow for kinematics and flexible components with repeatable alignment for multiple tests and, for example, multiple tests in atypical test environments.

[0034] The probe card can be mated to the base plate with a repeatability of 10 microns or about 10 microns. In one embodiment, this can be achieved by multiple adjustable rigid stops for overspeed and flatness. In one embodiment, three adjustable rigid stops are shown. In one embodiment, the adjustable rigid stops provide Z positioning and control. In one embodiment, multiple tapered locators can be assembled into holes in the flex plate and used to provide X&Y positioning and control. In one embodiment, tapered locating pins can provide rotational or theta positioning and control. In one embodiment, two tapered pins can be used, such as shown in the figure below.

[0035] The device under test (e.g., chip) can be held in the base plate by a spring clip that pushes the chip against a rigid stop. The probe tips of the probe card push the chip against the base plate. There can be temperature sensors on the probe card and the base plate. Three screws can secure the probe card to the base plate. A tungsten carbide cleaning plate can be inserted between the base plate and the probe card.

[0036] Figure 1A top perspective view of a probe card assembly 10 according to an embodiment is shown. The probe card assembly 10 includes a bottom plate 15, a top plate 20, and a probe card 25 fixed to the top plate 20. The bottom plate 15 can be fixed to a suitable test environment. For example, the bottom plate 15 can be installed in a cryostat, an oven, etc., depending on the desired test environment. For illustration purposes, Figure 1 The X, Y, and Z axes are included to indicate the X, Y, and Z directions.

[0037] Figure 2 It shows that according to the embodiment Figure 1 The bottom perspective view of the probe card assembly 10 is shown in FIG. The central portion 30 of the probe card 25 is adjustable to allow the probe card 25 to be precisely aligned with the device under test. The device under test can be placed on the test site 55 ( Figure 4 ) as follows Figure 4 As shown and described. A plurality of rigid stops 35 protrude from a surface of the top plate 20 (toward the bottom plate 15). In the illustrated embodiment, fasteners (e.g., screws, etc.) 37 protrude from the rigid stops 35. An adjustable lock 40 (e.g., a locking screw) can secure the rigid stops 35 in a desired position. For example, the adjustable lock 40 allows the rigid stops to be adjusted and secured in the Z direction.

[0038] Figure 3 It shows that according to the embodiment Figure 1 1 is a top perspective view of the probe card assembly 10 with the probe card 25 removed. In the illustrated embodiment, the geometry of the bottom plate 15 and the top plate 20 is an octagon. In one embodiment, the thickness of the bottom plate 15 can be 0.25 inches or approximately 0.25 inches thick. In one embodiment, the thickness of the top plate can be 0.3125 inches or approximately 0.3125 inches thick. It should be understood that these thicknesses are examples and that actual thicknesses can vary beyond the specified values ​​in accordance with the principles of the present specification.

[0039] Figure 4 It shows that according to the embodiment Figure 1 1 is a top perspective view of the probe card assembly 10 with the probe card 25 removed. In the illustrated embodiment, the top plate 20 includes three adjustable rigid stops 35. Fasteners such as, but not limited to, screws (e.g., Figure 2The fastener 37 in the probe card assembly 10 can be inserted into the rigid stop 35. This adjustment can control, for example, an overspeed device of an electrical contact in the probe card assembly 10. The flexible ring 45 is fixed to the bottom plate 15. The flexible ring 45 can be fixed with, for example, screws, pins, a suitable combination thereof, or the like. The flexible ring 45 includes a socket 50 for receiving a pin of the top plate 20 when assembled. In one embodiment, the socket 50 can be a hole into which a pin 80 can be inserted. In one embodiment, the pin 80 can be a tapered pin or pin with a chamfered or tapered surface. The pin 80 allows the top plate 20 to be loaded on top of the bottom plate 15 and the flexible ring 45 and then moved across the surface to help limit or control X, Y and / or θ movement.

[0040] The device under test may be held in place at the test site 55 by a plurality of rigid site stops 60 and flexible retainers 65 (eg, spring clips, etc.).

[0041] In one embodiment, the base plate 15 further includes a plurality of pads 70 for receiving the plurality of adjustable rigid stops 35. Thus, the number of pads 70 and the number of adjustable rigid stops 35 may be the same.

[0042] Figure 5 It shows that according to the embodiment Figure 1 1 is a cross-sectional view of the probe card assembly 10 with the probe card 25 removed. In the illustrated embodiment, a hole 75 is shown in the base plate 15 that is aligned with the fastener 37 that passes through the adjustable rigid stop 35. In one embodiment, the hole 75 is threaded to securely receive the fastener 37.

[0043] Figure 6 It shows that according to the embodiment Figure 1 1. A side view of the probe card assembly 10 of FIG. Two tapered pins 80 from the top plate 20 nest into receptacles 50 (e.g., holes) in the flex ring 45 attached to the bottom plate 15. When the probe card assembly is assembled, the pins 80 can establish the XY position. In one embodiment, when the pins 80 are inserted into the receptacles 50, the top plate with the probes is controlled to not move in θ (e.g., rotation) relative to the bottom plate 15. The flex ring 45 can deform (e.g., bend) until the rigid stop 35 bottoms out and helps define the Z position.

[0044] Figure 7 A top perspective view of a probe card assembly 100 according to an embodiment is shown. The probe card assembly 100 may be the same as or similar to the probe card assembly 10. The probe card assembly 100 in the illustrated embodiment includes a plurality of wires 105 electrically connected to the probe card 25 and capable of being electrically connected to a test device (not shown).

[0045] Fig. 8A and 8B It shows that according to the embodiment Figure 7The bottom plate 15 can be fixed in a test environment (e.g., Fig. 8A and 8B When the device under test is placed on the test site 55 for testing, the device under test can be inserted into the corner 110 ( Fig. 8A The opposite corner 115 of the device under test can rest on top of the rigid stop 60. The device under test can then be gently pushed toward the flexible holder 65 at the corner 115 (e.g., along the Figure 8B ) and downward (toward the base plate 15) until the device under test is placed on the test site 55.

[0046] Fig.9A and 9B The assembly according to the embodiment is shown Figure 7 Method of the probe card assembly 100. Arrow ( Fig.9A ) represents the direction in which the top plate 20 is mounted on the bottom plate 15. Once placed ( Fig. 9B ), the fastener 37 can be tightened to fix the probe card assembly 100.

[0047] Fig. 10A and 10B The installation according to the embodiment is shown Figure 7 The cleaning plate 150 in the probe card assembly 100 is shown in FIG. Fig. 10A A top view of the cleaning plate 150 is shown, Fig. 10B A bottom view of the cleaning plate 150 is shown. Fig. 10A , the cleaning plate 150 includes a cleaning pad 155 that is configured to align with the probe tip of the probe card 25. The cleaning pad 155 can be made of a material used to clean the probe tip. In one embodiment, the material can be a tungsten carbide material. In one embodiment, the material is textured tungsten carbide. Three rigid stops 160 can accommodate thickness variations of the cleaning plate 150. In one embodiment, the rigid stops 160 can be adjustable but fixed to a specific position during manufacturing. Fig. 10B As shown, three pins 165 are assembled into holes in the bottom plate 15 ( Fig. 10A , 10B 150). The tungsten carbide plate is bonded to the cleaning plate. Once the cleaning plate 150 is in place, the probe card 25 is mounted in the same manner as it is mounted to the base plate 15 (as described above). The probes of the probe card can be scrubbed against the cleaning pad 155 to remove debris from the probes.

[0048] In one embodiment, the cleaning plate 150 includes: Fig. 10BThe pin 180 shown, which can be a tapered pin (as shown), can be used to assemble the bottom of the cleaning plate 150 to the bottom plate 15. For example, the pin 180 can be inserted into the socket 50 of the bottom plate 15. Likewise, the cleaning plate 150 includes a socket 52 similar to the socket 50 of the bottom plate for receiving the pin 80 of the top plate 20. In one embodiment, the cleaning plate 150 can also have a flexible ring 145 in which the socket 52 is arranged.

[0049] Fig. 10C The installation according to the embodiment is shown Figure 7 The probe card assembly Fig. 10A and 10B As shown in the figure, the cleaning plate 150 is assembled between the top plate 20 (with the probe card) and the bottom plate 15.

[0050] It should be understood that in some embodiments, the bottom plate 15 is not required to use the cleaning plate 150. In this case, in one embodiment, the cleaning plate 150 can still receive the pins 80 of the top plate through the sockets 52 on the cleaning plate 150. However, at the bottom of the cleaning plate, there are no pins 165 or pins 180 because it is not necessary to assemble the cleaning plate 150 with the bottom plate 15. That is, for example, the bottom of the cleaning plate 150 can be flat without pins 165 or 180.

[0051] Semiconductor devices are not restrictive

[0052] The present disclosure is particularly applicable to probing semiconductor devices, but the use of the present teachings is not limited to probing semiconductor devices. Other devices may be applied to the teachings of the present invention. Therefore, although the present description refers to probing "semiconductor" devices, the term should be broadly interpreted to include probing any suitable device.

[0053] The terms used in this specification are intended to describe specific embodiments and are not intended to be limiting. Unless otherwise expressly stated, the terms "a", "an" and "the" also include plural forms. The terms "comprise" and / or "comprising", when used in this specification, specify the presence of the features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements and / or components.

[0054] With respect to the foregoing description, it should be understood that changes may be made in detail, especially in the construction materials employed and the shapes, sizes and arrangements of parts without departing from the scope of the present disclosure. This specification and the described embodiments are exemplary only, with the true scope and spirit of the present disclosure being indicated by the claims that follow.

Claims

1. A test assembly for testing a device under test, comprising: a base plate including test sites and holes; a top plate including an adjustable rigid stop configured to be secured to the bottom plate by a fastener configured to be inserted through the adjustable rigid stop and aligned with the hole to secure the top plate to the bottom plate to provide Z positioning and control; and a probe card fixed to the top plate and extending through the top plate to contact the device under test disposed on the test site, Wherein, the bottom plate comprises a flexible ring and a socket arranged in the flexible ring, The test site is disposed within a perimeter of the flexure ring, and the test site is configured to support the device under test, The top plate includes a pin, The pins can be inserted into the sockets, and when inserted, the pins of the top plate and the sockets of the bottom plate provide X and Y control, The flexure ring is configured to provide Z positioning and control, and The probe card is configured to push the device under test against the base plate.

2. The test assembly according to claim 1, wherein: The pin is tapered.

3. The test assembly according to claim 1, wherein: The pin is configured to provide rotational positioning and control.

4. The test assembly of claim 1, further comprising a cleaning plate and a cleaning pad.

5. The test assembly according to claim 4, wherein: The cleaning plate includes a flexible ring, and the cleaning pad is within a perimeter of the flexible ring of the cleaning plate.

6. The test assembly according to claim 4, wherein: The cleaning pad includes tungsten carbide.

7. The test assembly according to claim 1, wherein: The test site includes a rigid site stop and a flexible holder to allow the device under test to remain in place at the test site.

8. The test assembly according to claim 1, wherein: The base plate includes a pad configured to receive the adjustable rigid stop.

9. The test assembly according to claim 1, wherein: The top plate includes an adjustable lock configured to secure the adjustable rigid stop in a desired position in the Z position.

10. A method of assembling a test assembly for a device under test, comprising: assembling the test assembly as claimed in claim 1 by mounting the top plate including the probe card to the bottom plate; and The fasteners are tightened to secure the test assembly.

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