Wafer and substrate wire bonding joint quality test system

Abstract

The application discloses a wafer and substrate wire bonding point quality test system, which comprises a chip assembly guide platform and a wire bonding point quality test unit on the chip assembly guide platform; the wire bonding point quality test unit comprises a straight linear expander which is perpendicular to the guide direction of the chip assembly guide platform, and further comprises a pull rod which is parallel to the telescopic rod of the straight linear expander, and one end of the pull rod is fixedly connected with the end of the telescopic rod through a connecting arm; the wire bonding point quality test unit further comprises an electromagnet which is coaxial with the pull rod; the wire bonding point quality test unit has simple structure and can form consistent and same height wire bonding point quality tests on all arch-shaped wire bonding arrays at one time.

Description

Technical Field

[0001] This invention belongs to the field of wire bonding testing of wafers and substrates. Background Technology

[0002] In common chip packaging processes, the wafer and substrate are connected by multiple wires arranged in a straight array. If the solder joints at both ends of the wires are not strong, they may detach later. Therefore, it is necessary to sample and inspect the wire bonding quality of chip components on the chip production line. In existing wire bonding testing systems, a flexible upward pull is generally applied to each wire using a hook. If the solder joints at both ends of the wire that is flexibly pulled upward do not detach, it indicates that the soldering quality is qualified. Since there are a large number of wires connecting the wafer and the substrate, and they are arranged in an array, it would be inefficient to pull each wire in this way. Summary of the Invention

[0003] Purpose of the invention: In order to overcome the shortcomings of the prior art, the present invention provides a wafer-to-substrate wire bonding joint quality testing system, which can perform a one-time quality test on all arched wires on the wire bonding array to form a solder joint with the same height.

[0004] Technical solution: To achieve the above objectives, the present invention provides a wafer-to-substrate wire bonding joint quality testing system, comprising a chip assembly guiding platform and a wire bonding joint quality testing unit on the chip assembly guiding platform.

[0005] The wire bonding joint quality testing unit includes a linear telescoping device perpendicular to the guiding direction of the chip assembly guiding platform, and a pull rod parallel to the telescoping rod of the linear telescoping device. One end of the pull rod is fixedly connected to the end of the telescoping rod via a connecting arm. It also includes an electromagnet, which is coaxial with the pull rod. An elastic rope channel is coaxially arranged inside the pull rod near the electromagnet. An elastic rope that can be elastically stretched is arranged along the length of the elastic rope channel. One end of the elastic rope is fixedly connected to the bottom end of the elastic rope channel, and the other end of the elastic rope is fixedly connected to an iron cap. Under the elastic tension of the elastic rope, the iron cap is pressed against the end of the pull rod.

[0006] Furthermore, the wire bonding joint quality testing unit also includes a rotating shaft arranged parallel to the lower side of the linear telescoping device. The rotating shaft is rotatably mounted on a bearing seat via bearings. It also includes a torque output motor, which drives and connects to the rotating shaft. A strip seat is integrally connected to one side of the rotating shaft along the length direction. Several test rods are equidistantly arrayed along the length direction on the side of the strip seat away from the rotating shaft. Each test rod is parallel to the guiding direction of the chip assembly guiding platform.

[0007] Furthermore, the chip assembly under test consists of a wafer and a substrate; two rows of wire bonding arrays composed of several arched wire bondings are distributed along the contour edge on both sides of the chip assembly; under the drive of the displacement device, the chip assembly slides along the guide direction on the chip assembly guide platform, and the wire bonding array on one side of the chip assembly can be displaced along the guide direction of the chip assembly guide platform to cooperate with the wire bonding solder joint quality test unit.

[0008] Furthermore, the two ends of each arched wire are soldered to the pads on the wafer and the substrate, respectively; a straight channel extending along the array direction is formed within the wire bonding array by a number of arched wires, and the spacing between any two adjacent arched wires in the wire bonding array forms a wire bonding test channel.

[0009] Furthermore, when the wire bonding array on one side of the chip assembly moves along the guide direction of the chip assembly guide platform to cooperate with the wire bonding joint quality testing unit: a test rod passes through the lower part of the wire bonding test channel between any two adjacent arched wire bondings in a column of wire bonding arrays, and the pull rod and electromagnet are respectively located at the two ends of a straight channel extending along the array direction within the wire bonding array. The retraction movement of the telescopic rod allows the pull rod to extend into the straight channel along its length direction. When the telescopic rod is fully retracted, the iron cap at the end of the pull rod contacts the magnetic attraction end of the electromagnet; when the electromagnet is energized, the magnetic attraction end tightly magnetically attracts the iron cap; the magnetic attraction end tightly Based on the magnetically attracted iron cover, the extension movement of the telescopic rod causes the pull rod to be pulled out from the straight channel independently, while the iron cover remains at the magnetic end. This causes the elastic rope to be stretched in the straight channel. The clockwise rotation of the shaft drives each test rod to swing upward synchronously around the axis of the shaft in the wire-punching test track through the strip seat. This upward movement also drives the stretched elastic rope, causing it to swing upward with each test rod until it contacts each arched wire. As the test rod continues to swing upward, a section of the elastic rope between any two adjacent test rods undergoes a downward-pulling elastic deformation under the obstruction of the stationary arched wire.

[0010] Furthermore, the displacement device includes a guide rail parallel to the guiding direction of the chip assembly guide platform. A slider capable of displacement along the guide rail is provided on the guide rail. A translation arm is fixedly connected to the slider. A wafer chuck is connected to the translation arm via a lifter. The lifter can drive the wafer chuck to descend to the front and rear sides of the wafer holding the chip assembly, thereby causing the chip assembly and the wafer chuck to move together along the guiding direction of the chip assembly guide platform with the slider.

[0011] Furthermore, when the wire bonding array on one side of the chip assembly is combined with the wire bonding solder joint quality testing unit, the control lever extends into the straight channel along the length direction, and the magnetic end tightly magnetically attracts the iron cover. Then the lever is pulled out of the straight channel alone, while the iron cover remains at the magnetic end, causing the elastic rope to be stretched in the straight channel.

[0012] Furthermore, each test rod synchronously swings upwards around the axis of the rotating shaft in the wire bonding test corridor. The elastic rope between any two adjacent test rods undergoes a uniform downward tension-like elastic deformation due to the resistance of the stationary arched wires. If none of the arched wires on the wire bonding array fall off due to the tension-like elastic deformation of the elastic rope, it indicates that the welding quality at both ends of all the arched wires on the wire bonding array on the chip assembly side is qualified.

[0013] Beneficial effects: The structure of this invention is simple, and it can perform a one-time test on the solder joint quality of all arched wires on the wire bonding array with the same height. In particular, during "step seven": as the test rod continues to swing upward, the elastic rope between any two adjacent test rods undergoes a downward tension-like elastic deformation with the same amplitude under the obstruction of the stationary arched wires. This causes any arched wire to be subjected to the same upward flexible tension of the elastic rope, causing the ends of arched wires with weak solder joints to fall off. If none of the arched wires on the wire bonding array fall off due to the tension-like elastic deformation of the elastic rope, it indicates that the solder joint quality of both ends of all arched wires on the wire bonding array on the chip assembly side is qualified; otherwise, it is unqualified. Attached Figure Description

[0014] Appendix Figure 1 This is a schematic diagram of the chip assembly structure;

[0015] Appendix Figure 2 This is a schematic diagram of the overall structure of the test device at the end of "Step One";

[0016] Appendix Figure 3 This is a schematic diagram of the overall structure of the test device at the end of "Step Two";

[0017] Appendix Figure 4 For the appendix Figure 2 The schematic diagram with the displacement device hidden is shown.

[0018] Appendix Figure 5 This is a diagram showing the end of "Step Three";

[0019] Appendix Figure 6 This is a diagram showing the end of "Step Four";

[0020] Appendix Figure 7 This is a diagram showing the end of "Step Six";

[0021] Appendix Figure 8 This is a sectional view of the tie rod;

[0022] Appendix Figure 9 For "attached" Figure 7 A schematic diagram of the elastic rope undergoing tensile deformation during "Step Eight" from the perspective of "A". Detailed Implementation

[0023] The invention will now be further described with reference to the accompanying drawings.

[0024] As attached Figures 1 to 9 The wafer-to-substrate wire bonding joint quality testing system shown includes a chip assembly 9 composed of a wafer 9.1 and a substrate 9.2, as follows: Figure 1 As shown; two rows of wire bonding arrays consisting of several arched wire bonding 12 are distributed along the contour edge on both sides of the chip component 9. The two ends of each arched wire bonding 12 are respectively soldered to the pads 11 on the wafer 9.1 and the substrate 9.2; a straight channel extending along the array direction is formed in the wire bonding array consisting of several arched wire bonding 12, and the spacing between any two adjacent arched wire bonding 12 in the wire bonding array forms a wire bonding test channel 15;

[0025] like Figure 2 , 3 4; also includes a chip assembly guide platform 7, on which the chip assembly 9 is placed horizontally with the side with the wire bonding 12 facing upward. Driven by the displacement device, the chip assembly 9 slides along the guide direction on the chip assembly guide platform 7. Wire bonding joint quality testing units 1 are provided at both ends of the guide direction of the chip assembly guide platform 7. The wire bonding array on one side of the chip assembly 9 can be displaced along the guide direction of the chip assembly guide platform 7 to cooperate with the wire bonding joint quality testing unit 1.

[0026] The displacement device includes a guide rail 6 parallel to the guiding direction of the chip assembly guide platform 7. A slider 5 is provided on the guide rail 6, which can be displaced along the guide rail direction of the guide rail 6. A translation arm 4 is fixedly connected to the slider 5. A wafer chuck 2 is connected to the translation arm 4 through a lifter 3. The lifter 3 can drive the wafer chuck 2 to descend to the front and rear sides of the wafer 9.1 of the chip assembly 9, so that the chip assembly 9 and the wafer chuck 2 move together along the guiding direction of the chip assembly guide platform 7 with the slider 5.

[0027] like Figure 5 , 6 7; The wire bonding joint quality testing unit 1 includes a linear telescopic device 22 perpendicular to the guiding direction of the chip assembly guiding platform 7, and a pull rod 19 parallel to the telescopic rod 21 of the linear telescopic device 22. One end of the pull rod 19 is fixedly connected to the end of the telescopic rod 21 via a connecting arm 20, allowing the pull rod 19 to move along its length. It also includes a fixedly installed electromagnet support arm 24, on which an electromagnet 25 is fixedly supported. The electromagnet 25 is coaxially arranged with the pull rod 19. An elastic rope channel 16 is coaxially arranged inside the pull rod 19 near the end of the electromagnet 25. Figure 8An elastic rope 17, which can be elastically stretched, is provided along the length of the elastic rope channel 16. The elastic rope 17 is made of high-strength latex or rubber. One end of the elastic rope 17 is fixedly connected to the bottom end of the elastic rope channel 16, and the other end of the elastic rope 17 is fixedly connected to an iron cover 18. Under the elastic tension of the elastic rope 17, the iron cover 18 is attached to the end of the pull rod 19. A rotating shaft 28 is arranged parallel to the lower side of the linear telescoping device 22. The rotating shaft 28 is rotatably mounted on the bearing seat 27 through a bearing. It also includes a fixedly mounted torque output motor 23. The torque output motor 23 drives and connects to the rotating shaft 28. A strip seat 29 is integrally connected to one side of the rotating shaft 28 along the length. Several test rods 30 are equidistantly arranged along the length of the side of the strip seat 29 away from the rotating shaft 28. Each test rod 30 is parallel to the guide direction of the chip component guide platform 7.

[0028] When the wire bonding array on one side of the chip assembly 9 can be moved along the guiding direction of the chip assembly guide platform 7 to cooperate with the wire bonding joint quality test unit 1, a test rod 30 passes through the lower part of the wire bonding test passage 15 between any two adjacent arched wires 12 in a row of wire bonding arrays. The pull rod 19 and the electromagnet 25 are respectively located at the two ends of the straight channel extending along the array direction within the wire bonding array. The retraction movement of the telescopic rod 21 can cause the pull rod 19 to extend into the straight channel along the length direction. When the telescopic rod 21 is fully retracted, the iron cover 18 at the end of the pull rod 19 contacts the magnetic suction end 26 of the electromagnet 25. When the electromagnet 25 is energized, the magnetic suction end 26 tightly magnetically attracts the iron cover 18. Based on the iron cover 18, the extension movement of the telescopic rod 21 causes the pull rod 19 to be pulled out of the straight channel alone. The iron cover 18 remains at the magnetic end 26, causing the elastic rope 17 to be stretched in the straight channel. The clockwise rotation of the rotating shaft 28 drives each test rod 30 to swing upward synchronously around the axis of the rotating shaft 28 in the wire-punching test channel 15, and drives the already stretched elastic rope 17 upward. The stretched elastic rope 17 swings upward with each test rod 30 until it contacts each arched wire 12. As the test rod 30 continues to swing upward, a section of the elastic rope 17 between any two adjacent test rods 30 undergoes a downward-pulling elastic deformation under the obstruction of the stationary arched wire 12. Figure 9 This ensures that any arched bead 12 is subjected to an upward flexible tension from the elastic rope 17;

[0029] Work process

[0030] Step 1: Place the chip assembly guide platform 7 horizontally with the side with the bonding wire 12 facing upwards, as shown. Figure 2 ;

[0031] Step 2: Control the lifting device 3 to lower the chip chuck 2 to the front and rear sides of the chip 9.1 that is holding the chip assembly 9, thereby synchronizing the chip assembly 9 with the chip chuck 2; Figure 3 ;

[0032] Step 3: Control the slider 5 to make the chip assembly 9 and the wafer chuck 2 move together along the guide direction of the chip assembly guide platform 7 until the wire bonding array on one side of the chip assembly 9 moves along the guide direction of the chip assembly guide platform 7 to cooperate with the wire bonding joint quality test unit 1.

[0033] When the wire bonding array on one side of the chip assembly 9 is used in conjunction with the wire bonding solder joint quality testing unit 1, a test rod 30 passes through the lower part of the wire bonding test channel 15 between any two adjacent arched wires 12 on the side of the chip assembly 9, and the pull rod 19 and the electromagnet 25 are respectively located at the two ends of the straight channel extending along the array direction within the wire bonding array. At this time, the telescopic rod 21 is in a fully extended state; Figure 5 ;

[0034] Step four: Control the linear telescopic device 22 to gradually retract the telescopic rod 21. The retraction of the telescopic rod 21 causes the pull rod 19 to extend into the linear channel along its length. When the telescopic rod 21 is fully retracted, the iron cap 18 at the end of the pull rod 19 contacts the magnetic attraction end 26 of the electromagnet 25; Figure 6 As shown;

[0035] Step 5: Control the electromagnet 25 to be energized, and the magnetic end 26 to tightly magnetically attract the cover 18.

[0036] Step six: With the magnetic end 26 firmly magnetically attracting the iron cover 18, the telescopic rod 21 extends, causing the pull rod 19 to be pulled out of the straight channel alone. The iron cover 18 remains at the magnetic end 26, causing the elastic rope 17 to be stretched in the straight channel. Figure 7 As shown;

[0037] Step 7: Control the torque output motor 23 to apply clockwise torque to the rotating shaft 28, causing the rotating shaft 28 to rotate slowly clockwise. The clockwise rotation of the rotating shaft 28 drives each test rod 30 to swing upward synchronously around the axis of the rotating shaft 28 in the wire-punching test walkway 15 through the strip seat 29. This upward movement also drives the already stretched elastic rope 17, causing the stretched elastic rope 17 to swing upward with each test rod 30 until it contacts each arched wire-punching 12. As the test rod 30 continues to swing upward, the section of elastic rope 17 between any two adjacent test rods 30 undergoes a uniform downward tension-like elastic deformation due to the resistance of the stationary arched wire-punching 12. Figure 9This causes any arched wire 12 to be subjected to the same upward flexible tension of the elastic rope 17, causing the ends of arched wires 12 with poor welding quality to fall off. If none of the arched wires 12 on the wire array fall off due to the elastic deformation of the elastic rope 17, it means that the welding quality of both ends of all arched wires 12 on the wire array on one side of the chip assembly 9 is qualified; otherwise, it is unqualified.

[0038] Referring to the methods in "Steps Three" to "Steps Seven", the soldering quality of the wire bonding array on the other side of the chip assembly 9 can be inspected.

[0039] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A wafer-to-substrate wire bonding joint quality testing system, characterized in that, Includes a chip component guide platform (7) and a wire bonding joint quality testing unit (1) on the chip component guide platform (7); The wire bonding joint quality testing unit (1) includes a pull rod (19) perpendicular to the guiding direction of the chip assembly guide platform (7). The pull rod (19) can be displaced along the length direction. It also includes an electromagnet (25) and the pull rod (19) are coaxial. An elastic rope channel (16) is coaxially arranged inside the pull rod (19) near the electromagnet (25). An elastic rope (17) that can be elastically stretched is arranged in the elastic rope channel (16) along the length direction. One end of the elastic rope (17) is fixedly connected to the bottom end of the elastic rope channel (16). The other end of the elastic rope (17) is fixedly connected to an iron cover (18). Under the elastic tension of the elastic rope (17), the iron cover (18) is attached to the end of the pull rod (19). The wire bonding joint quality testing unit (1) also includes a rotating shaft (28). A strip seat (29) is integrally connected to one side of the rotating shaft (28) along the length direction. Several test rods (30) are equidistantly arranged on the side of the strip seat (29) away from the rotating shaft (28) along the length direction. Each of the test rods (30) is parallel to the guiding direction of the chip assembly guiding platform (7).

2. The wafer-to-substrate wire bonding joint quality testing system according to claim 1, characterized in that: The chip assembly (9) under test is composed of a wafer (9.1) and a substrate (9.2); two rows of wire bonding arrays composed of several arched wire bonding (12) are distributed along the contour edge on both sides of the chip assembly (9); under the drive of the displacement device, the chip assembly (9) slides on the chip assembly guide platform (7) along the guide direction, and the wire bonding array on one side of the chip assembly (9) can be displaced along the guide direction of the chip assembly guide platform (7) to cooperate with the wire bonding solder joint quality test unit (1).

3. The wafer-to-substrate wire bonding joint quality testing system according to claim 2, characterized in that: The two ends of each of the arched wires (12) are respectively soldered to the pads (11) on the wafer (9.1) and the substrate (9.2); a straight channel extending along the array direction is formed in the wire bonding array by a number of arched wires (12), and the spacing between any two adjacent arched wires (12) in the wire bonding array forms a wire bonding test channel (15).

4. The wafer-to-substrate wire bonding joint quality testing system according to claim 3, characterized in that: When the wire bonding array on one side of the chip assembly (9) moves along the guiding direction of the chip assembly guide platform (7) to cooperate with the wire bonding solder joint quality test unit (1): a test rod (30) passes through the lower part of the wire bonding test passage (15) between any two adjacent arched wires (12) of a wire bonding array, and the pull rod (19) and the electromagnet (25) are respectively located at the two ends of the straight channel extending along the array direction in the wire bonding array. The retraction movement of the telescopic rod (21) can make the pull rod (19) extend into the straight channel along the length direction. When the telescopic rod (21) is fully retracted, the iron cover (18) at the end of the pull rod (19) contacts the magnetic end (26) of the electromagnet (25); when the electromagnet (25) is energized, the magnetic end (26) tightly magnetically attracts the iron cover (18); the magnetic end (26) tightly magnetically attracts the iron. Based on the cover (18), the extension movement of the telescopic rod (21) causes the pull rod (19) to be pulled out from the straight channel alone. The iron cover (18) remains at the magnetic end (26), causing the elastic rope (17) to be stretched in the straight channel. The clockwise rotation of the rotating shaft (28) drives each test rod (30) to swing upward in the wire test track (15) around the axis of the rotating shaft (28) through the strip seat (29), and drives the stretched elastic rope (17) upward, so that the stretched elastic rope (17) swings upward with each test rod (30) until it contacts each arched wire (12). As the test rod (30) continues to swing upward, a section of elastic rope (17) between any two adjacent test rods (30) undergoes a downward string-like elastic deformation under the obstruction of the arched wire (12) that remains stationary.

5. The wafer-to-substrate wire bonding joint quality testing system according to claim 4, characterized in that: The elastic rope (17) is made of latex or rubber.

6. The operating method of the wafer-substrate wire bonding joint quality testing system according to claim 5, characterized in that: Make the wire bonding array on one side of the chip assembly (9) cooperate with the wire bonding solder joint quality test unit (1), control the pull rod (19) to extend into the straight channel along the length direction, and the magnetic end (26) tightly magnetically attracts the iron cover (18). Then the pull rod (19) is pulled out from the straight channel alone, and the iron cover (18) remains at the magnetic end (26), so that the elastic rope (17) is stretched in the straight channel. The test rod (30) is made to swing upward in the wire bonding test walkway (15) synchronously around the axis of the rotating shaft (28). The elastic rope (17) between any two adjacent test rods (30) undergoes a downward string-like elastic deformation with the same amplitude under the obstruction of the stationary arched wire (12). If none of the arched wires (12) on the wire bonding array fall off due to the string-like elastic deformation of the elastic rope (17), it indicates that the welding quality at both ends of all the arched wires (12) on the wire bonding array on one side of the chip assembly (9) is qualified.

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