KR102603357B1 - Apparatus and method for performing tests on interconnect bonds - Google Patents

Abstract

An interconnection joint testing device for testing the joint strength of an electronic device includes at least one interconnection joint attached to the electronic device. The interconnect joint test apparatus has a positioning mechanism and a test tool assembly mounted on the positioning mechanism. The test tool assembly is configured to press the first portion of the interconnect joint and pull the second portion of the interconnect joint. The positioning mechanism is operative to align the test tool assembly to the interconnect joint during testing and to apply a pressing force to a first portion of the interconnect joint and a traction force to a second portion of the interconnect joint. The interconnect joint testing device has a jig including at least one force sensing element mounted on the jig. The at least one force sensing element is configured to apply a resisting force to the test tool assembly when engaged by the test tool assembly.

Description

Apparatus and method for performing tests on interconnection joints {APPARATUS AND METHOD FOR PERFORMING TESTS ON INTERCONNECT BONDS}

The present invention relates to an apparatus and method for testing the strength of interconnections, such as wire joints, in electronic devices, and in particular to an apparatus capable of performing both shear and traction tests.

During semiconductor assembly and packaging, wire joints are used for electrical interconnection between the semiconductor die and the substrate. To perform wire splicing, a wire is provided from the coil containing the splicing wire into a capillary tube. Each joint typically consists of a length of gold or copper wire bonded to the substrate surface.

It is important to test joint strength so that the user can be confident that the particular wire or interconnect joint formed is acceptable. Due to the size of the joints, the test tools used to test the joint strength of these joints must be able to accurately measure very small forces and deflections.

There are several known types of bond tests, for example shear tests and traction tests. The shear test tests the shear strength of a joint by applying a shear force to the side of the joint and shearing the joint from the substrate. The traction test tests the tensile strength of the wire joint by pulling the wire at the wire joint.

Machines that perform these tests typically have a test tool that can be positioned relative to the joint for testing. The test is then performed by moving the test tool, typically measuring the force required to break the joint. It is relatively time consuming as users must perform these tests manually and use different machines to perform different types of tests.

Additionally, machine performance can vary over time, causing forces generated by motors or detected by sensors to drift over a period of time. If this occurs during a production run, it affects test accuracy. Therefore, users must manually perform force measurements periodically, sometimes weekly or even daily, as a form of preventive maintenance of the testing machine. This is tedious and time-consuming. As a result, the overall equipment efficiency of the machine is reduced.

It would be beneficial to design an interconnect bond testing device that avoids and overcomes these drawbacks.

Accordingly, it is an object of the present invention to provide an interconnection joint testing apparatus configured to perform shear and traction tests on interconnection joints formed on electronic devices.

Another object of the present invention is to provide an interconnection joint testing device configured to perform self-monitoring mechanical force testing.

Accordingly, a first aspect of the present invention provides an interconnection joint testing apparatus for testing the bond strength of an electronic device comprising at least one interconnection joint attached to the electronic device, the interconnection joint testing apparatus comprising: positioning mechanism; a test tool assembly mounted on the positioning mechanism and configured to press a first portion of the interconnect joint and pull a second portion of the interconnect joint during testing; and the jig comprising at least one force sensing element mounted to the jig, wherein the at least one force sensing element is configured to exert a resistive force on the test tool assembly when engaged by the test tool assembly. and wherein the positioning mechanism aligns the test tool assembly with the interconnect joint during the test, applies a pushing force to the first portion of the interconnect joint and applies a pulling force to the second portion of the interconnect joint. It works to apply a pulling force.

In one embodiment, the test tool assembly includes a first test tool configured to apply the pressing force to press the first portion of the interconnect joint and a second test tool configured to apply the pulling force to pull the second portion of the interconnect joint. 2 Includes testing tools.

In one embodiment, the direction of the pressing force is perpendicular to the direction of the pulling force.

In one embodiment, the interconnect joint testing device further comprises at least one sensor coupled to the first and second test tools, wherein the at least one sensor detects the first and second sensors when the pressing force and the pulling force are applied. Operates to determine reaction forces applied to the second test tool.

In one embodiment, the at least one sensor is a first force sensor.

In one embodiment, the first testing tool has a tip at a lower end distal to the positioning mechanism, the tip configured to engage the first portion of the interconnect abutment when the pressing force is applied.

In one embodiment, the second testing tool has a hook on a distal end of the second testing tool distal to the positioning mechanism, the hook configured to engage the second portion of the interconnection joint when the traction force is applied. It is composed.

In one embodiment, the at least one force sensing element includes at least one curved portion.

In one embodiment, the jig further includes a constant weight mounted on the jig, and the test tool assembly is configured to engage and lift the constant weight.

In one embodiment, the constant weight is a dead mass.

In one embodiment, the at least one force sensing element further includes a second force sensor.

In one embodiment, the second force sensor is a strain gauge.

In one embodiment, the jig further includes a lever mass mounted on the jig, and the test tool assembly is configured to engage and lift the lever mass.

In one embodiment, the second force sensor is a piezoelectric sensor.

In one embodiment, the second force sensor is a bend sensor.

According to a second aspect of the invention, a method is provided for testing the bond strength of an electronic device comprising at least one interconnection joint attached to the electronic device, the method comprising: a test tool assembly mounted on a positioning mechanism; providing steps; moving the test tool assembly with the positioning mechanism to align the test tool assembly with the interconnect joint; applying a pressing force to a first portion of the interconnect joint and applying a pulling force to a second portion of the interconnect joint by the test tool assembly; engaging a force sensing element mounted on a jig with the test tool assembly; and determining reaction forces applied to the test tool assembly by the force sensing element.

In one embodiment, the test tool assembly includes a first test tool configured to apply the pressing force to a first portion of the interconnect joint and a second test tool configured to apply the traction force to a second portion of the interconnect joint. Includes.

In one embodiment, the steps of applying the pressing force and the pulling force further include determining reaction forces applied to the first and second tools by at least one sensor coupled to the first and second tools.

These and other features, aspects and advantages will be better understood upon reference to the description section, appended claims and accompanying drawings.

Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings.
1 is an isometric view of an interconnection bonding testing apparatus according to a first preferred embodiment of the present invention.
Figure 2 is a front view of the positioning mechanism with the test tool assembly mounted.
Figure 3 is an isometric view of a jig with a force sensing element and dead mass mounted on the jig.
Figure 4A is a front view of a positioning mechanism with a test tool engaging a jig during self-monitoring mechanical shear force testing.
Figure 4b is an enlarged view of a force sensing element indicated by fiducial marks.
Figure 5A is an isometric view of a jig with force sensing elements coupled by a first testing tool.
Figure 5B is a graph showing the machine learning relationship between the reaction force on the tip of a shear tool and the distance moved by the shear tool.
Figure 6A is an isometric view of a traction tool engaging and lifting a dead mass.
FIG. 6B is a side view of the traction tool of FIG. 6A with sensors connected to the traction tool.
Figure 6C is a graph showing the force required by a traction tool to lift a dead mass over a period of time.
Figure 7a is an isometric view of an interconnection joint testing apparatus according to a second preferred embodiment of the present invention.
FIG. 7B is a side view of the interconnect bond testing apparatus of FIG. 7A.
Figure 8a is a side cross-sectional view of an interconnection joint testing apparatus according to a second preferred embodiment of the present invention.
Figure 8b is a plan view of a wire bonding test device according to a second preferred embodiment of the present invention.
FIG. 8C is a cross-sectional view taken along line AA of FIG. 8B.
Figure 9a is a side cross-sectional view of a third preferred embodiment of the invention with a curved sheet mounted on a jig.
Figure 9B is a top view of Figure 9A with a plurality of curved sheets mounted on a jig.
Figure 10 is a side view of a shear tool being pressed against a force sensor.

Figure 1 is an isometric view of an interconnection bonding testing device 10 according to a first preferred embodiment of the present invention. The interconnect joints to be tested may be produced using, for example, a wire splicing machine. The interconnect joint test apparatus 10 generally includes a positioning mechanism 20 on which a test tool assembly 22 is mounted, a pair of front and rear tracks 12, 14, and a jig 30.

The jig 30 is mounted on the frame 18, which in turn is mounted on the front track 12. The jig 30 may have a plurality of through holes 38. Jig 30 may be mounted to frame 18 via any suitable fastening means, such as screws or fasteners secured through through holes 38. Alternatively, jig 30 may also be mounted to frame 18 with a suitable adhesive. Frame 18 may be mounted to front track 12 via any suitable fastening means, such as screws or fasteners. Alternatively, frame 18 may also be mounted to front track 12 using a suitable adhesive. The jig 30 is therefore in a fixed position relative to the front track 12.

The front and rear tracks 12, 14 are laterally spaced such that the front track 12 is located between the jig 30 and the rear track 14. The front track 12 is generally parallel to the rear track 14. The stage 16 is disposed between the front track 12 and the rear track 14 and is configured to receive an electronic device supported on a substrate, such as a lead frame 19, for testing. In this example, we refer to a lead frame.

However, those skilled in the art will understand that the present disclosure for testing bond strength is equally applicable to substrates other than lead frames.

Lead frame 19 may be secured to stage 16 through a clamping mechanism. For example, the lead frame 19 may be mechanically clamped to the stage via a gripper (not shown) and then held in place on the stage 16 via vacuum suction means created on the stage 16. Lead frame 19 is configured to be coupled by test tool assembly 22 during shear testing or wire pull testing.

Positioning mechanism 20 may be connected to an XY drive mechanism (not shown) that drives positioning mechanism 20 across the XY axis in a horizontal plane. The XY drive mechanism may alternatively be connected to the stage 16 holding a lead frame 19 that drives the stage 16 across the XY axis in a horizontal plane. A separate Z-direction driving mechanism (not shown) is connected to the positioning mechanism 20 to drive the positioning mechanism 20 to move vertically in the Z-direction. The X, Y and Z direction drive mechanisms may be actuated to function together or individually to move the positioning mechanism 20 according to programmed instructions from the processor. For example, positioning mechanism 20 may be programmed to move test tool assembly 22 such that test tool assembly 22 is positioned over and engages an interconnection joint on lead frame 19.

Interconnection joint testing apparatus 10 may be configured to perform both ball shear testing and wire pull testing on interconnection joints of, for example, electronic devices. Although this disclosure refers to interconnect joints, those skilled in the art will understand from this disclosure that the invention is not limited thereto. For example, interconnect joints include wire joints, ball joints, ball bumps, ball stitch on ball (BSOB), bonded ball on stitch (BBOS), ball vertical array (BVA), stacked die wire joints, die attach joints, and wedge joints. may, but is not limited to these. The following describes how the ball shear test and wire traction test can be performed according to one embodiment of the present invention.

Referring to FIG. 1 , test tool assembly 22 is configured to perform ball shear testing and/or wire pull testing on an electronic device supported on a lead frame 19 . The stack of lead frames to be tested may be loaded into a magazine (not shown) spaced apart from the stage 16. The lead frame to be tested can be determined by the user. During testing, a feeder (not shown) presses the selected lead frame onto the stage 16. The lead frame 19 may be mechanically clamped to the stage via a gripper (not shown) and then held in place on the stage 16 via vacuum suction generated from the stage 16.

During a ball shear test, the XY drive mechanism drives the positioning mechanism 20 so that the shear tool of the test tool assembly 22 is positioned over the interconnect joint to be tested. The Z-direction drive mechanism then drives the positioning mechanism 20 to move vertically downward toward the interconnect joint to be tested. When the shear tool contacts the top surface of the electronic device or the lead frame 19 adjacent the interconnect joint to be tested, the positioning mechanism 20 rises vertically upward by a predetermined height to shear tool 24 by the same height. Raise it. The predetermined height is user programmable and can vary depending on the size of the interconnect joint to be tested. The positioning mechanism 20 is then driven by the XY drive mechanism to press the interconnect joint until the interconnect joint is completely sheared. The interconnect joint exerts a reaction force on the tip of the shear tool when the shear tool presses against the interconnect joint. A sensor connected to the shear tool measures the reaction force required to fully press the interconnect joint in the lead frame from which the ball shear force is derived.

In an alternative arrangement in which the XY drive mechanism is connected to the stage 16, the It is located above. The Z-direction drive mechanism then drives the positioning mechanism 20 to move vertically downward toward the interconnect joint to be tested. When the shear tool contacts the top surface of the electronic device or the lead frame 19 adjacent the interconnect joint to be tested, the positioning mechanism 20 rises vertically upward by a predetermined height to shear tool 24 by the same height. Raise it. The predetermined height is user programmable and can vary depending on the size of the interconnect joint to be tested. The XY drive mechanism then drives the stage to press against the tip of the shear tool 24 until the interconnect joint is completely sheared.

During a wire pull test, the XY drive mechanism drives the positioning mechanism 20 to position the pull tool of the test tool assembly 22 over the interconnect joint to be tested. The Z-direction drive mechanism then drives the positioning mechanism 20 to move vertically downward toward the interconnect joint to be tested. The hook of the pulling tool engages the wire of the interconnection joint to be tested. The Z-direction drive mechanism initially drives the traction tool to pull the wires of the interconnect joint upward toward the positioning mechanism until the resulting wire breaks or the joint fails and is lifted off the lead frame 19. Sensors connected to the pulling tool measure the pulling force required to lift the wire until the wire breaks or the joint fails, from which the wire pulling force is derived.

In an alternative arrangement in which the XY drive mechanism is connected to the stage 16, the It is located above the joint. The Z-direction drive mechanism then drives the positioning mechanism 20 to move vertically downward toward the interconnect joint to be tested. The hook of the pulling tool engages the wire of the interconnection joint to be tested. The Z-direction drive mechanism then drives the pull tool to pull the wires of the interconnect joint upward toward the positioning mechanism until the wire breaks or the joint fails and is lifted off the lead frame 19. Accordingly, the interconnect joint testing apparatus of the present invention allows both shear testing and traction testing to be performed on the same machine. This therefore eliminates the need to use multiple machines to perform different types of tests or manually change test tools on the machines. Advantageously, little or no human intervention is required because the ball shear test and wire pull test are automated and the results can be transmitted to a processor.

The choice of test to be performed (ball shear or wire traction) is at the user's discretion and can be programmed according to the user's requirements. For example, a user may prefer to perform a wire pull test first before a ball shear test to save costs. In this example, if a wire pull test is performed until the wire breaks, a ball shear test can be performed using the remaining ball joint. This minimizes resource waste. However, if the ball shear test is performed first, the wire pull test cannot be performed on the same ball joint that has already been sheared.

After the ball shear and wire pull tests are performed on the lead frame, a pressurizing device (not shown) removes the lead frame from stage 16. Stage 16 is now ready to receive the next lead frame for testing. This allows the entire interconnect bond testing to be fully automated without human intervention.

When operating the interconnect joint test device 10, the performance of the drive mechanism and sensors may vary over time, causing the drive force and sensed force to drift over a period of time, making testing increasingly inaccurate. Accordingly, it is advantageous to periodically test the interconnect bond test device 10 to ensure that it continues to operate as expected, particularly in the absence of human intervention.

2 is a front view of the positioning mechanism 20 with the test tool assembly 22 mounted thereon. Test tool assembly 22 includes a shear tool 24 and a traction tool 26. The shearing tool 24 has a tip 25 located at a lower end distal to the positioning mechanism 20 . Tip 25 preferably has a tapered shape (shown more clearly in Figure 5a). Shearing tool 24 is connected to a sensor (not shown). The traction tool 26 has a hook 27 located at its lower end distal to the positioning mechanism 20 . Traction tool 26 is connected to sensor 38 (shown in FIG. 6B).

Image sensor 28 is also mounted on positioning mechanism 20 and spaced apart from test tool assembly 22. Accordingly, the image sensor 28 is movable together with the positioning mechanism 20. The image sensor 28 may be in the form of a camera, and the image sensor 28 is positioned so that the jig 30 is visible. Image sensor 28 is operable to align test tool assembly 22 with jig 30 so that a self-monitoring mechanical force test can be performed.

Figure 3 is an isometric view of a jig 30 that may be used with a preferred embodiment of the present invention. There is a force sensing element 32 and a dead mass 34 mounted on a jig 30. The force sensing element 32 is preferably mounted on the top surface of the jig 30 and is configured to be depressed by the shear tool 24 during a self-monitoring mechanical shear force test. The area surrounding the force sensing element 32 should preferably be kept clean to prevent interference when the test tool assembly 22 performs a self-monitoring mechanical shear force test. Force sensing element 32 may be made of any flexible or other suitable material that elastically deflects, deforms, or shears when a force is applied. The force sensing element 32 may be, but is not limited to, a bend, a sheet, a machined metal, a spring-resilient component, a strain gauge, a piezoelectric sensor, a flex sensor, or a force sensor. Preferably, force sensing element 32 is of regular shape with multiple sidewalls, such as four sidewalls. This is advantageous because it allows more than one point of contact on the force sensing element 32 during self-monitoring mechanical shear force testing. Shearing tool 24 may be configured to press force sensing element 32 against any of the four side walls of force sensing element 32 .

Jig 30 may have a plurality of through holes 38 for mounting jig 30 to frame 18 using suitable fastening means such as screws and fasteners. In the embodiment shown in Figure 3, two holes are shown. However, any number of holes may be used to operatively connect jig 30 to front track 12.

A certain weight, such as a dead mass 34, is located on the jig support member 35 mounted on the side wall of the jig 30. Alternatively, jig support member 35 may be formed as a single piece with jig 30. The jig support member 35 extends from the jig 30 preferably in a direction parallel to the front track 12. The dead mass 34 is configured to be seated on the upper surface of the jig support member 35. Dead mass 34 can be made of any material of known mass (e.g. free weight). The wire 36 is attached to the upper surface of the dead mass 34. The wire 36 is configured to be engaged by the traction tool 26 during a self-monitoring machine traction test. The wire 36 may be made of at least a soft metal so that the wire 36 does not break when the pulling tool 26 lifts the dead mass 34. Wire 36 is preferably made of a hard material such as metal.

4A is a front view of a positioning mechanism 20 with a shear tool 24 engaging a force sensing element 32 during a self-monitoring mechanical shear force test. During a self-monitoring machine shear test, an XY drive mechanism coupled to positioning mechanism 20 drives positioning mechanism 20 to a position where test tool assembly 22 is vertically above jig 30.

A fiducial mark 39 (see FIG. 4B) may be marked on the jig 30 so that the image sensor 28 can see it. A fiducial mark 39 can be marked on the force sensing element 32 such that when the image sensor 28 captures an image of the fiducial mark 39, the shear tool 24 performs a self-monitoring mechanical shear force test. so that it is aligned over the force sensing element (32). A fiducial mark 39 may also be marked on the surface of the dead mass 34 such that when the image sensor 28 captures an image of the fiducial mark 39, the traction tool 26 performs a self-monitoring mechanical traction test. It is arranged on the dead mass 34 to perform. Alternatively, the fiducial marks 39 may be marked on both the force sensing element 32 and the dead mass 34 such that when the image sensor 28 captures an image of one of the fiducial marks 39, the shear Tool 24 and traction tool 26 may be aligned respectively on force sensing element 32 or dead mass 34 to perform self-monitoring mechanical force testing. The fiducial mark 39 may be of any shape or shape as long as it is visible to the image sensor 28 or may be located anywhere along the jig, force sensing element, or dead mass. Preferably, the fiducial mark 39 is located on the top surface of the jig, a force sensing element or dead mass, so as to obtain an unobstructed view of the fiducial mark 39 by the image sensor 28 .

Image sensor 28 verifies the alignment of test tool assembly 22 and jig 30 when image sensor 28 captures an image of a fiducial mark 39 marked on jig 30. Any offsets and deviations from the alignment captured by image sensor 28 can be corrected by signals sent to the XY drive mechanism.

Once the alignment of the test tool assembly 22 and the jig 30 is confirmed, the positioning mechanism 20 is moved by the Z-direction drive mechanism to move the shear tool 24 in the vertical direction toward the force sensing element 32. It can be driven. In the embodiment shown in FIG. 4A , shear tool 24 contacts force sensing element 32 . The traction tool 26 is in a “rest” position at this stage, during which it does not engage the wire 36 of the dead mass.

Figure 5A is an isometric view of jig 30 with force sensing element 32 coupled by shear tool 24. The tip 25 of the shearing tool 24 is configured to press against the side wall of the force sensing element 32 . The Z-direction drive mechanism drives the positioning mechanism 20 vertically downward until the tip 25 contacts the top plate 31 located on the upper surface of the jig 30. Upon contact with the top plate 31, the positioning mechanism 20 is raised vertically upward by a predetermined height and causes the shear tool 24 to rise to the same height. The predetermined height is user programmable and may vary depending on the characteristics of the force sensing element 32 used. The top plate 31 may be made of a hard material such as sapphire.

The positioning mechanism 20 can then be driven by an XY drive mechanism to move and press the side wall of the force sensing element 32 in direction S, as shown in Figure 5A. The force sensing element 32 will deform elastically and generate a reaction force R on the tip 25. A sensor connected to the shear tool 24 measures the reaction force (R) acting on the tip 25 and transmits the data to the processor. The processor records the value of the reaction force (R) and the distance moved by the shear tool (24).

The relationship between the reaction force R acting on the tip 25 and the distance moved by the shear tool 24 is learned by the machine and the results may be as shown in FIG. 5B. In the embodiment shown in Figure 5a, the shearing tool 24 presses the force sensing element 32 in direction S. The shearing tool 24 also presses the force sensing element 32 against any one of the four side walls of the force sensing element 32 to obtain a reaction force R against the tip 25 of the shearing tool 24. You should know that it can be configured.

In Figure 5b, the relationship between the reaction force R generated at the tip 25 of the shearing tool 24 and the distance moved by the shearing tool 24 is learned and the learned tilt ratio is obtained. Self-monitoring mechanical shear force tests can be programmed to be performed regularly according to the user's preferences and needs. For example, a self-monitoring mechanical shear force test can be programmed to run weekly or monthly. The results from each shear test can be tabulated and the slope ratio compared to the learned slope ratio. Ideally, the fluctuations and deviations of the learned gradient ratio should be minimized. Tolerance can be determined by the user. Preferably, the recommended tolerance is +/- 0.5%. If the test results are out of tolerance, the user may be alerted by the processor so that necessary compensation and/or corrective actions can be taken at the shear tool 24 and/or sensors.

Shearing tool 24 and tip 25 are advantageously made of a hard material, such as metal. For example, the shear tool may be made of titanium or aluminum-lithium alloy and the tip may be made of tungsten carbide. Typically, tip 25 may be sized or shaped to fit the interconnect joint being tested. Accordingly, the tip 25 is interchangeable, so that larger or smaller tips can be used for larger or smaller joints.

6A is an isometric view of the pulling tool 26 engaging and lifting the dead mass 34. Dead mass 34 rests on jig support member 35. The retraction tool 26 has a hook 27 at the distal end of the retraction tool 26 away from the positioning mechanism 20 . The wire 36 attached to the upper surface of the dead mass is coupled by the hook 27 and pulled upward in the direction of the positioning mechanism 20. During a self-monitoring machine traction test, when the traction tool 26 is aligned with the wire 36 of the dead mass 34, a Z-direction drive mechanism (not shown) causes the hook 27 to engage the wire 36. Drive the traction tool (26) vertically downward. The Z-direction drive mechanism drives the traction tool 26 upward toward the positioning mechanism 20. The pulling tool 26 lifts the dead mass 34 in a direction L away from the jig support member 35. Sensor 38 is connected to traction tool 26 as shown in FIG. 6B. Sensor 38 may be in the form of a force gauge. Sensor 38 measures the force required to lift dead mass 34 from jig support member 35. The force required to lift the dead mass 34 from the jig support member 35 should be constant over time as shown in the graph of FIG. 6C.

Alternatively, a self-monitoring mechanical traction test may be performed on the force sensing element 32. In this case, the force sensing element 32 may be mounted on the jig 30 such that a portion of the force sensing element 32 extends from the force sensing element 32 . A notch (not shown) may be formed near the edge of the force sensing element 32 and configured to be engaged by the hook 27 of the traction tool 26. During a self-monitoring machine traction test, the traction tool (26) is aligned with the notch in the force-sensing element (32) and the Z-direction drive mechanism causes the hook (27) to engage the notch in the force-sensing element (32). Drive (26) vertically downward. The Z direction drive mechanism then drives the traction tool 26 upward in the direction of the positioning mechanism 20. The force sensing element 32 is elastically deformed and generates a reaction force on the hook 27. A sensor connected to the traction tool 26 measures the reaction force acting on the hook 27 and transmits the data to the processor. The processor records the value of the reaction force and the distance moved by the traction tool 26. The relationship between the reaction force acting on the hook 27 and the distance moved by the pulling tool 26 is learned by the machine and the result may be similar to the learned tilt ratio shown in FIG. 5B.

Self-monitoring machine traction tests can be programmed to be performed regularly according to the user's preferences and needs. For example, a self-monitoring machine force test can be programmed to run weekly or monthly. The results obtained from each traction test can be compared to a constant force graph or learned slope ratio. Ideally, variations and deviations from a constant force graph or learned slope ratio should be minimized. Tolerance can be determined by the user. Preferably, the recommended tolerance is +/- 0.5%. If the test results are out of tolerance, the user may be alerted by the processor so that necessary compensation and/or corrective actions can be taken at the traction tool 26 and/or sensors 38. Therefore, machine performance over time can be self-monitored.

The hook 27 is advantageously made of a hard material such as metal. Typically, hooks 27 may be sized to suit the interconnect joint being tested. Accordingly, the hooks 27 are interchangeable and accordingly larger or smaller hooks can be used. This allows self-monitoring of equipment performance over time. No human intervention is required to manually perform force measurements using other test tools. This reduces the likelihood of equipment failure, lowers maintenance costs, reduces downtime and improves production quality.

7A and 7B are isometric and side views, respectively, of an interconnection bonding testing apparatus according to a second preferred embodiment of the present invention. The jig 30 has a cavity 47 and is mounted on the frame 18 such that the front track 12 is received within the cavity 47 of the jig (as shown in Figure 7b). The jig is accommodated within housing 40. The upper surface of housing 40 has a pair of grooves located at the ends of housing 40 proximal to front track 12. The grooves are configured to accommodate the shear tool 24 and the traction tool 26 during self-monitoring mechanical force testing. The force sensing element is mounted on a jig such that the force sensing element is positioned above the front track (12). As shown in FIG. 7B , the tip 25 of the shearing tool 24 and the pulling tool 26 are positioned above the front track 12 . Therefore, in this embodiment, the working area of the self-monitoring machine force test is above the front track 12. This is particularly advantageous for machines where the positioning mechanism has a shorter reach and where space constraints do not allow adequate access to the force sensing elements to perform self-monitoring machine force tests.

Figure 8a is a side cross-sectional view of an interconnection joint testing apparatus according to a second preferred embodiment of the present invention. The force sensing element in this embodiment may be a lever mass 42. The lever mass 42 is mounted on the jig 30 via a U-bracket 51 and secured with a suitable fixing means such as a fastener 44. The lever mass 42 rotates about the pivot 43 when a traction force is applied to the opposite end of the lever mass 42. The notch is located at the opposite end of the lever mass 42 and is adapted to engage the hook 27 and be pulled upward in the direction of the positioning mechanism.

During a self-monitoring machine traction test, when the traction tool 26 is aligned with the notch in the lever mass 42, a Z-direction drive mechanism (not shown) drives the traction tool 26 vertically down to engage the hook 27. engages with the notch of the lever mass (42). The Z direction drive mechanism drives the traction tool 26 upward in the direction of the positioning mechanism 20. Accordingly, the pulling tool 26 lifts the opposite end of the lever mass 42 in direction L1. Accordingly, the lever mass 42 rotates around the pivot pin 43. Sensor 38 is connected to traction tool 26 as previously shown in FIG. 6B. Sensor 38 may be in the form of a force gauge. Sensor 38 measures the reaction force acting on hook 27 and transmits the information to the processor. The processor records the value of the reaction force and the distance moved by the towing tool. The relationship between the reaction force acting on the hook 27 and the distance moved by the pulling tool 26 is learned by the machine and the results are shown in Figure 5b.

FIG. 8B is a plan view of an interconnection bonding testing device according to a second preferred embodiment of the present invention, and FIG. 8C is a cross-sectional view taken along line A-A of FIG. 8B. A second force sensing member, which may be in the form of a strain gauge, such as the load cell strain gauge 41 shown in FIG. 8B, is mounted on the jig 30 at one end. A nub (nub) 45 is located at the opposite end of the load cell strain gauge 41, which is distal to the jig 30. The load cell strain gauge 41 is mounted on the jig 30 through the protrusion 52 and secured through the C-clamp fastener 46. C-clamp fasteners (46) securely secure the load cell strain gauge (41) to the jig (30).

During a self-monitoring mechanical shear force test, the tip 25 of the shear tool 24 is configured to press against the nub 45 of the load cell 41. The Z direction drive mechanism drives the positioning mechanism vertically down until the tip 25 is aligned with the nub 45 of the load cell 41. Then, the positioning mechanism can be driven by the XY drive mechanism to move and press the nub 45 in direction S1, as shown in Figure 8c. The load cell strain gauge 41 is elastically deformed to generate a reaction force on the tip 25. A sensor connected to the shearing tool 24 measures the reaction force acting on the tip 25 and transmits the information to the processor. The processor records the value of the reaction force and the distance moved by the shear tool 24. The relationship between the reaction force acting on the tip 25 and the distance moved by the shear tool 24 is learned by the machine and the results may be as shown in FIG. 5B.

Figure 9a is a side cross-sectional view of a jig according to a third preferred embodiment of the present invention in which a bent sheet is mounted on the jig. A force sensing member, such as flexed sheet 48, is mounted to jig 30 via fasteners 44. The self-monitoring machine traction test may be performed as similarly described in the previous embodiment. During a self-monitoring machine traction test, the traction tool 26 may be configured to lift the free end of the flexure sheet 48 proximal to the front track 12 . A sensor attached to the traction tool 26 measures the reaction force acting on the hook 27 and transmits the information to the processor. The processor records the value of the reaction force and the distance moved by the traction tool 26. The relationship between the reaction force acting on the hook 27 and the distance moved by the pulling tool 26 is learned by the machine and the results may be as shown in Figure 5b.

FIG. 9B is a top view of FIG. 9A with a plurality of curved sheets mounted on jig 30. A force sensing member, such as a plurality of curved sheets 49, is mounted on the jig 30. The plurality of flex sheets 49 are configured to engage the tip 25 of the shear tool 24 during a self-monitoring mechanical shear force test. The shearing tool 24 presses the plurality of curved sheets 49 at protrusions 53 located at ends of the plurality of curved sheets 49 distal to the jig 30. A sensor connected to the shear tool 24 measures the reaction force acting on the tip and transmits the information to the processor. The processor records the value of the reaction force and the distance moved by the shear tool 24. The relationship between the reaction force acting on the tip 25 and the distance moved by the shear tool 24 is learned, and the results may be as shown in FIG. 5B.

Although various examples have been provided regarding the use of force sensing members to perform self-monitoring mechanical force tests, those skilled in the art will understand from the above disclosure that the examples provided herein are not limited thereto. For example, instead of bending and flexing members, force sensors, piezoelectric sensors or other known sensors configured to measure forces directly or indirectly may be mounted on the jig 30 as schematically shown in FIG. 10 .

Although the invention has been described in considerable detail with reference to specific embodiments, other embodiments are possible.

Accordingly, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained therein.

Claims (19)

An interconnection joint testing device for testing the bond strength of an electronic device comprising at least one interconnection joint attached to the electronic device, comprising:
The interconnection joint test device includes:
positioning mechanism;
a test tool assembly mounted on the positioning mechanism and configured to press a first portion of the interconnect joint to perform a shear test and pull a second portion of the interconnect joint to perform a traction test during testing; and
The jig comprising at least one force sensing element mounted to the jig, the test tool assembly configured to perform a mechanical force test by determining a reaction force exerted on the test tool assembly by the at least one force sensing element. comprising the jig further configured to engage the at least one force sensing element,
The positioning mechanism may be configured to apply a pushing force to a first portion of the interconnect joint and a pulling force to a second portion of the interconnect joint by the test tool assembly during testing. An interconnection joint testing device operative to align a test tool assembly to the interconnection joint. According to claim 1,
The test tool assembly includes a first test tool configured to apply the pressing force to press the first portion of the interconnect joint and a second test tool configured to apply the traction force to pull the second portion of the interconnect joint. An interconnection bonding test device comprising: According to claim 1,
The direction of the pressing force is perpendicular to the direction of the pulling force. According to claim 2,
further comprising at least one sensor coupled to the first and second testing tools, wherein the at least one sensor is operative to determine reaction forces applied to the first and second testing tools when the pressing force and the traction force are applied. interconnection bonding test device. According to claim 4,
Wherein the at least one sensor is a first force sensor. According to claim 2,
The first test tool has a tip at a lower end distal to the positioning mechanism, the tip configured to engage the first portion of the interconnect joint when the pressing force is applied. According to claim 2,
wherein the second test tool has a hook at a distal end of the second test tool distal to the positioning mechanism, the hook configured to engage the second portion of the interconnect abutment when the traction force is applied. Joint test device. According to claim 1,
and wherein the at least one force sensing element has at least one curved portion. According to claim 8,
The jig further includes a constant weight mounted on the jig, and the test tool assembly is configured to engage with the constant weight and lift the constant weight. According to clause 9,
Wherein the constant weight is a dead mass. According to claim 1,
and wherein the at least one force sensing element includes a second force sensor. According to claim 11,
wherein the second force sensor is a strain gauge. According to claim 12,
The jig further includes a lever mass mounted on the jig, and the test tool assembly is configured to engage the lever mass and lift the lever mass. According to claim 11,
Wherein the second force sensor is a piezoelectric sensor. According to claim 11,
wherein the second force sensor is a flexure sensor. According to claim 1,
wherein the positioning mechanism is further operative to move the test tool assembly to engage the at least one force sensing element during the mechanical force test. 1. A method for testing the bond strength of an electronic device comprising at least one interconnection joint attached to the electronic device, the method comprising:
providing a test tool assembly mounted on a positioning mechanism;
moving the test tool assembly with the positioning mechanism to align the test tool assembly with the interconnect joint;
applying a pressing force by the test tool assembly to a first portion of the interconnect joint to perform a shear test and applying a traction force to a second portion of the interconnect joint to perform a traction test;
coupling the test tool assembly with a force sensing element mounted on a jig to perform a mechanical force test; and
A method comprising determining reaction forces exerted on the test tool assembly by the force sensing element. According to claim 17,
wherein the test tool assembly includes a first test tool configured to apply the pressing force to the first portion of the interconnect joint and a second test tool configured to apply the traction force to the second portion of the interconnect joint. . According to claim 18,
When applying the pressing force and the pulling force, determining reaction forces applied to the first and second tools by at least one sensor coupled to the first and second tools.

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