CN112067436B - A Test Method for Lead Strength of Beam Devices - Google Patents

Abstract

The invention relates to a method for testing the lead strength of a beam type device, belonging to the field of transverse tensile strength testing of beam type leads; step one, manufacturing a rectangular plate-shaped substrate; step two, manufacturing a rectangular plate-shaped microstrip line on the upper surface of the substrate; step three, preparing a beam type device to be tested; horizontally placing the substrate, and horizontally placing the beam type device to be tested on the upper surface of the substrate; and the gold-plated beam lead on one side of the beam device to be tested is bonded to the micro-strip line of the substrate; bonding two ends of the gold wire to the gold-plated beam lead on the other side to form a gold wire ring; step six, vertically fixing the substrate on a wafer bearing table of the tensile testing equipment; seventhly, the draw hook penetrates through the golden wire ring of the U-shaped structure, and the golden wire ring is vertically and upwards drawn by the draw hook; step eight, recording tension data, and completing a measurement test of the transverse tensile strength of the lead of the beam type device to be tested; the invention realizes simple, direct and effective measurement of the transverse tensile strength of the beam type lead.

Description

A Test Method for Lead Strength of Beam Devices

technical field

The invention belongs to the field of performance testing of electronic components and relates to a test method for the lead wire strength of a beam type device.

Background technique

A beam device is a device with a suspended beam lead structure, and its package is a bare chip without an additional shell package. The beam lead diode chip is the most common in aerospace applications. Beam-type devices use gold-plated metal beams to replace the metal leads of conventional devices, and are directly connected to the microstrip circuit, canceling the shell package, reducing the shell capacitance, and have the characteristics of simple structure, small size, small capacitance, and small parasitic parameters. , is widely used in microwave circuit systems such as high-frequency broadband integrated mixers, detectors, switches, and VCOs.

When the beam device is applied, the beam leads on both sides are usually installed on the microstrip line of the substrate by wire bonding. Due to the small size of the product, it is difficult to install, and the lead wire may crack or even fall off under the temperature stress of the application. Therefore, in the verification of aerospace applications, it is necessary to focus on the evaluation of assembly reliability and application adaptability of beam devices. Among them, the beam device lead strength is a key test item for the evaluation of assembly reliability and application adaptability.

When the beam device is applied, it is assembled in the substrate circuit. Under the temperature stress, due to the different thermal expansion coefficients of the shell, the substrate and the beam lead, the beam lead may be subjected to an outward pulling force or Inward squeezing force, causing the lead wire to crack or even fall off from the root. Therefore, the transverse tensile strength of the beam lead is one of the key reliability indicators for evaluating whether the beam lead device is suitable for aerospace applications. However, there is currently no effective test method for evaluating the transverse tensile strength of beam leads at home and abroad.

At present, when evaluating the beam strength of beam leads, the existing measurement and test standards for evaluating the strength of beam leads are based on the method 2011.1 bonding strength (destructive bonding tensile test) in GJB 548B-2005 "Test Methods and Procedures for Microelectronic Devices" ) in "3.1.5 Test condition G-push-off test (beam lead)" and "3.1.6 Test condition H-pull-off test (beam lead)". In these two test conditions, the force applied to the device is push force or pull force, both of which are longitudinal forces perpendicular to the lead. The evaluation is the adhesion of the beam lead on the chip and the bonding strength with the substrate, and the device lead cannot be measured. Transverse tensile strength, and this index is one of the most important indexes in the practical application of beam devices in aerospace.

CN 105510225 A patent of the 41st Research Institute of China Electronics Technology Group Corporation discloses a bonding strength test method. A blind groove is processed between the two pads of the blind groove, and the interconnection lead or beam lead device to be tested is bonded to the pad of the thin film or thick film circuit. The bonding point is the corresponding pad on both sides of the blind groove; the bonding The completed pads are placed on the chip support table of the tensile test equipment, and the test hooks pass through the blind groove from the bottom of the interconnection lead or beam lead device to be tested and then fixed with the interconnection lead or beam lead device to be tested for non-destructive testing. destructive and destructive bond strength testing". This method only improves the non-destructive operation of the bonding strength test. The purpose of the evaluation test is still the adhesion of the beam lead on the chip, and the peeling force of the bond strength of the beam lead and the device with the substrate, and it cannot measure the device. Lead transverse tensile strength.

To sum up, the existing standard methods lack effective test methods for measuring the transverse tensile strength of beam-leaded devices.

Contents of the invention

The technical problem solved by the invention is: to overcome the deficiencies of the prior art, to propose a test method for the strength of beam-type device leads, and to realize the simple, direct and effective measurement of the transverse tensile strength of the beam-type leads.

The technical solution of the present invention is:

A method for testing the lead strength of a beam device, comprising the steps of:

Step 1, making a rectangular plate-shaped substrate;

Step 2, making a rectangular plate-shaped microstrip line on the upper surface of the substrate;

Step 3. Prepare the beam device to be tested;

Step 4. Place the substrate with the microstrip line horizontally, place the beam device to be tested horizontally on the upper surface of the substrate; bond the gold-plated beam lead on one side of the beam device to be tested to the microstrip line of the substrate superior;

Step 5, bonding the two ends of the gold wire to the gold-plated beam lead on the other side of the beam device to be tested to form a gold wire ring;

Step 6. Vertically fix the substrate with the gold-plated beam wire bonding on both sides of the beam device to be tested on the wafer holder of the tensile testing equipment;

Step 7. Pass the pull hook of the tensile tester through the gold wire ring, and pull the gold wire ring vertically upward along the length direction of the gold-plated beam lead;

Step 8, record the tensile data, and complete the measurement test of the transverse tensile strength of the lead wire of the beam device to be tested.

In the above-mentioned test method for the lead strength of a beam-type device, in the first step, the substrate is made of alumina ceramic material or 4003 copper clad laminate material; the length of the substrate is greater than or equal to 10mm; the width is 5-10mm; the thickness is 0.3- 0.5mm.

In the test method of the lead strength of a kind of beam device above-mentioned, in described step 2, the manufacturing method of microstrip line is:

The microstrip line is made by thin film technology at the width side of the upper surface of the substrate; the upper surface of the microstrip line is electroplated with a gold layer, and the thickness of the gold layer is greater than or equal to 1.27 μm; the gold content in the gold layer is greater than or equal to 99.99%; the width of the microstrip line is not Less than 2 times the width of the gold-plated beam lead.

In the above-mentioned method for testing the lead strength of a beam-type device, in the step 3, the beam-type device to be tested adopts a beam-type device with a suspended beam-type lead structure, a bare chip, and no shell package; There are 2 gold-plated beam leads on the beam device; the 2 gold-plated beam leads are symmetrically arranged on the side wall of the beam device to be tested, and are located on a uniform horizontal plane; the gold-plated beam leads are made of gold material, and the gold content is greater than or equal to 99.99% .

In the test method of the lead strength of a kind of beam type device above-mentioned, in described step 4, the bonding method of gold-plated beam type lead wire and microstrip line is:

Use a semi-automatic bonding machine for bonding, the furnace temperature is 120-140°C during bonding; the temperature of the riving knife is 100-120 ℃; the pressure is 90-100g; the port of the riving knife in the semi-automatic bonding machine adopts a rectangular structure; The port size is 150 μm × 50 μm.

In the above-mentioned method for testing the lead wire strength of a beam-type device, in the fifth step, the gold wire ring is a U-shaped wire-like structure with an open end, and the axial length of the gold wire is not less than 2mm; the tensile strength of the gold wire ring is Greater than the tensile strength of the gold-plated beam lead; the tensile strength of the gold-plated beam lead is not less than 0.3N (30gf) times the width of the gold-plated beam lead.

In the test method of the wire strength of the above-mentioned beam type device, in the step five, the method of bonding the two ends of the gold wire with the gold-plated beam type wire is:

Use a semi-automatic bonding machine for bonding, the furnace temperature is 120-140°C during bonding; the temperature of the riving knife is 100-120 ℃; the pressure is 90-100g; the port of the riving knife in the semi-automatic bonding machine adopts a rectangular structure; The port size is 150 μm × 50 μm.

In the above-mentioned method for testing the lead strength of a beam-type device, in the sixth step, when the substrate is vertically fixed on the carrier table of the tensile test equipment, the deviation angle of the substrate along the vertical direction is -10°～10° .

In the above-mentioned method for testing the lead wire strength of a beam-type device, in the sixth step, when the pull hook pulls the gold wire ring vertically upward, the deviation angle of the pull hook along the vertical direction is -10° to 10°.

The beneficial effect of the present invention compared with prior art is:

(1) The present invention realizes the test of the transverse tensile strength of the lead wire of the beam device, solves the problem that the reliability index evaluation that is very concerned about the practical application of the beam device has no basis for evaluation, and provides a method suitable for all beam devices. Test guidance for the measurement, evaluation, and assessment of the transverse tensile strength of the lead wire of the beam type device; it fills in a gap in the strength test method of the beam type lead wire;

(2) The present invention ensures a gold-plated beam lead on one side of the beam device by selecting a rigid or semi-rigid substrate of a suitable size and adopting a thin film process on the substrate to make a gold-plated microstrip line with sufficient thickness and purity to meet the bonding process requirements Reliable bonding with the microstrip line on the substrate; by selecting U-shaped gold wires with appropriate diameter, length, and material, and an appropriate bonding method, the tensile strength of the U-shaped gold wire ring is guaranteed to be greater than that of the gold-plated beam lead Strength: Fix the substrate with wire bonding on both sides of the beam device vertically on the support table of the tensile test equipment, and use the hook of the test equipment to pull the U-shaped gold wire ring vertically upward along the length direction of the gold-plated beam lead. Guaranteed test accuracy and validity of test results;

(3) The present invention is ingenious in design, simple to manufacture, and low in cost. It only needs to make additional substrate circuits, microstrip lines, and U-shaped gold wire rings to complete the beam-type devices that belong to the bare chip packaging form and are difficult to install. The test of the transverse tensile strength of the lead wire;

(4) The present invention is easy to operate, and will not cause damage to the beam device body or lead wires during the test process, avoiding rework or repetition of the test caused by changing the test sample, and improving test efficiency.

Description of drawings

Fig. 1 is a schematic diagram of the beam lead strength test of the present invention.

Detailed ways

The present invention will be further elaborated below in conjunction with embodiment.

The invention fills up the deficiency of the existing beam-type lead wire strength test method, and provides a simple, direct and effective test method for measuring the transverse tensile strength of the beam-type lead wire.

The test principle of the present invention is: bond the gold-plated beam lead 6 on one side of the beam device 3 to be tested on the microstrip line 2 of the substrate 1; bond the U-shaped beam lead 6 on the other side The gold wire ring 4; the gold wire ring 4 is hooked by the pull hook 5 of the tensile tester, and a transverse tensile force relative to the beam device 3 to be tested is applied, the tensile data is recorded, and the failure category is observed and recorded.

The test method for the lead strength of the beam device, as shown in Figure 1, specifically includes the following steps:

Step 1. First, make test hardware, and make a rectangular plate-shaped substrate 1; the substrate 1 is made of alumina ceramic material or 4003 copper-clad laminate material; the length of the substrate 1 is greater than or equal to 10mm; the width is 5-10mm; the thickness is 0.3-0.5mm.

Step 2, making a rectangular plate-shaped microstrip line 2 on the upper surface of the substrate 1; the method of making the microstrip line 2 is: using a thin film process to make the microstrip line 2 at the width edge position of the upper surface of the substrate 1; the upper surface of the microstrip line 2 The surface is electroplated with a gold layer, and the thickness of the gold layer is greater than or equal to 1.27 μm; the gold content in the gold layer is greater than or equal to 99.99%; the width of the microstrip line 2 is not less than twice the width of the gold-plated beam lead 6 .

Step 3, prepare the beam device 3 to be tested; the beam device 3 to be tested adopts a beam device with a suspended beam lead structure, a bare chip, and has no shell package; the beam device 3 to be tested is provided with two gold-plated Beam leads 6; two gold-plated beam leads 6 are symmetrically arranged on the side wall of the beam device 3 to be tested, and are located on a uniform horizontal plane; the gold-plated beam leads 6 are made of gold, and the gold content is greater than or equal to 99.99%. The gold-plated beam lead 6 and the microstrip line 2 both use gold with a content greater than or equal to 99.99%, so as to ensure reliable bonding.

Step 4. Place the substrate 1 with the microstrip line 2 horizontally, place the beam device 3 to be tested on the upper surface of the substrate 1 horizontally; bond the gold-plated beam lead 6 on one side of the beam device 3 to be tested to the microstrip line 2 of the substrate 1; the bonding method of the gold-plated beam lead 6 and the microstrip line 2 is as follows: a semi-automatic bonding machine is used for bonding, and the furnace temperature is 120-140°C during bonding; 100-120°C; pressure 90-100g; the port of the riving knife in the semi-automatic bonding machine adopts a rectangular structure; the size of the riving knife port is 150 μm×50 μm.

Step five, bond the two ends of the gold wire on the gold-plated beam lead 6 on the other side of the beam device 3 to be tested to form a gold wire ring 4; the gold wire ring 4 is a U-shaped wire structure with an open end, and the gold wire The axial length of the wire is not less than 2 mm; the U-shaped gold wire ring 4 should be gold wire with a suitable diameter; the diameter of the gold wire should be selected so that the tensile strength of the gold wire ring 4 is greater than the tensile strength of the gold-plated beam lead 6; The tensile strength of the gold-plated beam lead 6 is not less than 0.3N30gf multiplied by the width of the gold-plated beam lead 6 .

The method of bonding the two ends of the gold wire with the gold-plated beam lead wire 6 is: use a semi-automatic bonding machine for bonding, and the furnace temperature is 120-140°C during bonding; the chopper temperature is 100-120°C; the pressure is 90-100g ; The port of the riving knife in the semi-automatic bonding machine adopts a rectangular structure; the size of the riving knife port is 150 μm×50 μm. During bonding, the U-shaped gold wire ring 4 is placed horizontally, and the U-shaped open end of the U-shaped gold wire ring 4 is bonded to the gold-plated beam lead 6 on the other side of the beam device 3 to be tested.

Step 6. Vertically fix the substrate 1 bonded with the gold-plated beam-type leads 6 on both sides of the beam-type device 3 to be tested on the support platform of the tensile test equipment; vertically fix the substrate 1 on the support platform of the tensile test equipment , the deviation angle of the substrate 1 along the vertical direction is -10°-10°.

Step 7. Pass the pull hook 5 of the tensile tester through the gold wire ring 4, and pull the gold wire ring 4 vertically upward along the length direction of the gold-plated beam lead 6; The deviation angle of the drag hook 5 along the vertical direction is -10°-10°.

Step 8: Record the tensile force data, and complete the measurement test of the transverse tensile strength (ie along the length direction of the gold-plated beam lead 6 ) of the lead 3 of the beam device to be tested.

Example 1

1. An alumina ceramic substrate is used to make the substrate 1. The dimensions of the substrate are: length 12mm, width 7mm, and thickness 0.3mm.

2. The microstrip line 2 is manufactured on the substrate 1 by thin film or thick film technology, and the surface of the microstrip line 2 is coated with gold, and the thickness of the gold layer is 5 μm. The microstrip line 2 has a width of 0.3mm and a length of 4mm.

3. Prepare the silicon-based beam lead diode 3 to be tested. The chip width is 0.26 mm and the length is 0.28 mm (not counting the lead length). The gold-plated beam leads on both sides are respectively 0.12 mm wide, 0.2 mm long, and 0.01 mm thick.

4. Bond the gold-plated beam lead 6 on one side of the silicon-based beam lead diode 3 to be tested to the microstrip line 2 of the substrate 1;

5. On the other side of the silicon-based beam lead diode 3 to be tested, bond the gold wire ring 4 on the gold-plated beam lead 6 to form a U-shape; the U-shaped gold wire has a diameter of 38 μm and a length of 2.5 mm;

6. Place the substrate 1 that has been bonded with the device on the support table of the tensile test equipment, fix the substrate 1, and reach the U-shaped gold wire ring 4 with the pull hook 5 for testing, and pull the gold wire ring 4 along the length direction of the lead wire;

7. Record the tensile force data, observe and record the failure category, and record the tensile force value. If the tensile force value is greater than 0.036N, it is determined that the transverse tensile strength of the lead wire of the beam lead diode 3 is qualified.

Example 2

The realization steps of the present invention are as follows:

1. Use 4003 copper-clad laminates to make the substrate 1. The dimensions of the substrate are: length 15mm, width 10mm, and thickness 0.5mm.

2. The microstrip line 2 is manufactured on the substrate 1 by thin film or thick film technology, and the surface of the microstrip line 2 is coated with gold, and the thickness of the gold layer is 5 μm. The microstrip line has a width of 0.5mm and a length of 5mm.

3. Prepare the silicon-based beam lead diode 3 to be tested. The chip width is 0.6 mm, and the length is 0.6 mm (not counting the lead length). The gold-plated beam leads on both sides are respectively 0.15 mm wide, 0.2 mm long, and 0.01 mm thick.

4. Bond the gold-plated beam lead 6 on one side of the silicon-based beam lead diode 3 to be tested to the microstrip line 2 of the substrate, as shown in figure 6 .

5. On the other side of the silicon-based beam lead diode 3 to be tested, bond a gold wire ring 4 to the gold-plated beam lead 6 to form a U-shaped gold wire with a diameter of 50 μm and a length of 3 mm.

6. Place the substrate 1 that has been bonded to the tensile test equipment on the substrate 1, fix the substrate 1, reach the U-shaped bonding ring with the hook 5 for testing, and pull the gold wire ring 4 along the length of the lead wire.

7. Record the tensile force data, observe and record the failure category, and record the tensile force value. If the tensile force value is greater than 0.045N, it is determined that the transverse tensile strength of the lead wire of the beam lead diode 3 is qualified.

Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention, and any person skilled in the art can use the methods disclosed above and technical content to analyze the present invention without departing from the spirit and scope of the present invention. Possible changes and modifications are made in the technical solution. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention, which do not depart from the content of the technical solution of the present invention, all belong to the technical solution of the present invention. protected range.

Claims (7)

1. a test method of beam device lead wire strength, is characterized in that: comprise the steps: Step 1, making a rectangular plate-shaped substrate (1); Step 2, making a rectangular plate-shaped microstrip line (2) on the upper surface of the substrate (1); Step 3, preparing the beam device (3) to be tested; in the step 3, the beam device to be tested (3) adopts a beam device with a suspended beam lead structure, a bare chip, and no shell package; Two gold-plated beam leads (6) are arranged on the beam-type device (3) to be tested; the two gold-plated beam-type leads (6) are symmetrically arranged on the side walls of the beam-type device (3) to be tested, and are located on the same horizontal plane; The gold-plated beam lead (6) is made of gold, and the gold content is greater than or equal to 99.99%; Step 4. Place the substrate (1) with the microstrip line (2) horizontally, place the beam device (3) to be tested on the upper surface of the substrate (1) horizontally; place the beam device (3) to be tested The gold-plated beam lead (6) on one side is bonded to the microstrip line (2) of the substrate (1); Step 5. Bond both ends of the gold wire to the gold-plated beam lead (6) on the other side of the beam device (3) to be tested to form a gold wire ring (4); the gold wire ring (4) is open at one end The U-shaped filament structure, the axial length of the gold wire is not less than 2mm; the tensile strength of the gold wire ring (4) is greater than the tensile strength of the gold-plated beam lead (6); the tensile strength of the gold-plated beam lead (6) The strength is not less than 0.3N (30gf) multiplied by the width of the gold-plated beam lead (6); Step 6, vertically fix the substrate (1) bonded with the gold-plated beam leads (6) on both sides of the beam device (3) to be tested on the wafer carrier of the tensile testing device; Step 7. Pass the pull hook (5) of the tension tester through the gold wire ring (4), and pull the gold wire ring (4) vertically upward along the length direction of the gold-plated beam lead (6); Step 8, record the tensile data, and complete the measurement test of the transverse tensile strength of the lead wire of the beam device (3) to be tested. 2. the test method of a kind of beam device lead strength according to claim 1, is characterized in that: in described step 1, described substrate (1) adopts alumina ceramic material or 4003 copper clad laminate material; Substrate (1 ) is greater than or equal to 10mm in length; 5-10mm in width; and 0.3-0.5mm in thickness. 3. the test method of a kind of beam device lead strength according to claim 2, is characterized in that: in described step 2, the manufacture method of microstrip line (2) is: The microstrip line (2) is manufactured by thin film technology at the width side position of the upper surface of the substrate (1); the upper surface of the microstrip line (2) is electroplated with a gold layer, and the thickness of the gold layer is greater than or equal to 1.27 μm; the gold content in the gold layer is greater than or equal to 99.99%; the width of the microstrip line (2) is not less than twice the width of the gold-plated beam lead (6). 4. the test method of a kind of beam type device lead strength according to claim 3, is characterized in that: in described step 4, the bonding method of gold-plated beam type lead (6) and microstrip line (2) is: Use a semi-automatic bonding machine for bonding, the furnace temperature is 120-140°C during bonding; the temperature of the riving knife is 100-120 ℃; the pressure is 90-100g; the port of the riving knife in the semi-automatic bonding machine adopts a rectangular structure; The port size is 150 μm × 50 μm. 5. the test method of a kind of beam-type device lead strength according to claim 4, is characterized in that: in described step 5, the method that gold wire two ends and gold-plated beam-type lead (6) bonding is: Use a semi-automatic bonding machine for bonding, the furnace temperature is 120-140°C during bonding; the temperature of the riving knife is 100-120 ℃; the pressure is 90-100g; the port of the riving knife in the semi-automatic bonding machine adopts a rectangular structure; The port size is 150 μm × 50 μm. 6. the test method of a kind of beam device lead wire strength according to claim 5, it is characterized in that: in described step 6, when substrate (1) is vertically fixed on the chip platform of tensile test equipment, substrate ( 1) The deviation angle along the vertical direction is -10°～10°. 7. the test method of a kind of beam device lead wire strength according to claim 6, it is characterized in that: in described step 7, when draw hook (5) hooks up vertically and pulls gold thread ring (4), draw hook (5) ) The deviation angle along the vertical direction is -10°～10°.

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