Solder column production device and method for packaging ceramic column grid array

Abstract

The invention discloses a solder column production device and method for ceramic column grid array packaging, the device comprises a cutter for cutting a solder column and a containing groove, a solid carrier for embedding a finished solder wire is arranged in an inner cavity of the containing groove, and the finished solder wire is arranged in and fixed in the solid carrier in a straightened state; the method comprises the following steps: straightening a prepared finished solder wire; the straightened finished solder wire is placed and fixed in the accommodating groove; a flowing state carrier is poured into the containing groove, and pouring is stopped after the flowing state carrier submerges the solder wires; cooling and solidifying the flowing carrier to form the solid carrier; the solid carrier is cut into short sections through a blade, and the blade is perpendicular to the axis of the straightened solder wire; and the obtained short section is heated, and the solder column is taken out after the short section is melted. The solder column prepared through the method is small in length error, good in end face flatness and simple in operation procedure, and has the advantages of being small in pollution and good in environmental protection property.

Description

Technical Field

[0001] The invention belongs to the technical field of ceramic column grid array devices, and in particular relates to a solder column production device and method for ceramic column grid array packaging. Background Art

[0002] Ceramic column grid array package (CCGA for short) is developed on the basis of CBGA packaging technology. Compared with traditional BGA packaging devices, CCGA packaging devices have the advantages of good thermal matching, vibration resistance, impact resistance, high temperature resistance, high reliability, easy cleaning, etc. The use of column grid instead of ball grid greatly alleviates the thermal fatigue problem caused by thermal expansion mismatch between ceramic carrier and epoxy glass cloth printed circuit board; at the same time, the large number of I / O numbers solves the micro-processing needs of multi-logic and large amounts of data. Therefore, this type of packaging device is widely used in high-reliability products.

[0003] One of the core components of ceramic column grid array packaging devices is the solder column. Commonly used solder columns include copper solder columns and tin solder columns. The quality of the solder column, especially its end face accuracy, is a key factor affecting its welding reliability.

[0004] In the prior art, the solder column manufacturing method disclosed in document CN102470493B includes: a first step of conveying the wire solder from an insertion port for inserting the wire solder to a discharge port for discharging the wire solder inserted into the insertion port, so that the wire solder protrudes from the discharge port; a second step of cutting the wire solder protruding from the discharge port by using a first cutting knife, and cutting the wire solder inserted into the insertion port by using a second cutting knife; a solder column cutting machine disclosed in document CN106270294A, It includes a base, on which a loading device, a conveying device, a correction device, a cutting device and a hopper are arranged in sequence. The loading device consists of a support frame with a positioning shaft, a clamping ring and a pressing plate, the support frame is arranged on the base, the clamping ring is arranged on the positioning shaft and is fixed by the pressing plate; the conveying device consists of a fixed frame and an active roller shaft, a driven roller shaft and a motor arranged on the fixed frame, the fixed frame is arranged on the base, the active roller shaft is connected to the output shaft of the motor, the driven roller shaft cooperates with the active roller shaft, and the driven roller shaft is arranged above the active roller shaft.

[0005] However, the solder pillars produced by the aforementioned equipment still have the problem of low end face accuracy. Even the solder pillars produced by Haipu Semiconductor (Luoyang) Co., Ltd., a domestic technology leader, can only control their length error within ±0.03mm, and their end face flatness is also poor. Further optimizing their length error and end face accuracy has always been a research hotspot and difficulty in this field. Summary of the invention

[0006] The object of the present invention is to provide a device and method for producing solder columns with good end surface flatness for ceramic column grid array packaging.

[0007] In order to achieve the above object, the present invention adopts the following technical solution.

[0008] A solder column production device for ceramic column grid array packaging includes a tool for cutting solder columns, and is characterized in that: the device also includes a receiving groove, a solid carrier for burying finished solder wire is arranged in the inner cavity of the receiving groove, and the finished solder wire is built into and fixed in the solid carrier in a straightened state.

[0009] In order to reduce the production cost of the solder column, as one of the preferred solutions of the present invention, the solid carrier is solid paraffin.

[0010] In order to reduce the production cost of solder columns, as the second preferred solution of the present invention, the solid carrier is a glutinous rice block or a flour block in a frozen state, the water content in the glutinous rice block or the flour block does not exceed 20% of its total weight, and the freezing temperature is not higher than -10°C.

[0011] In order to further improve the end surface flatness of the end surface solder column, the glutinous rice block is formed by consolidating glutinous rice powder with a particle size of no more than 800 meshes and paste, and the flour block is formed by consolidating flour with a particle size of no more than 800 meshes and paste.

[0012] As a preferred solution of the present invention, along the width direction of the accommodating groove, the cross-section of the accommodating groove is trapezoidal, arc-shaped, rectangular or U-shaped.

[0013] In order to further improve the flatness of the end surface of the solder column and reduce the length error of the solder column, a gap is provided on the side wall of the receiving groove just enough for the blade of the tool to enter and exit, and the low point of the gap is lower than the position of the finished solder wire.

[0014] As a more preferred solution, the width between two adjacent seams is equal to the standard width of the solder column.

[0015] For easy operation, both ends of the receiving groove are sealed with detachable end covers, and the seam of the side wall of the receiving groove is sealed with a detachable film or tape.

[0016] Furthermore, two ends of the finished solder wire are fixed on a clamp, and the clamp is fixed outside or in the inner cavity of the accommodating groove.

[0017] The method for preparing a solder column based on the above device is characterized in that the steps include: Step 1, straightening the prepared finished solder wire; Step 2, placing and fixing the straightened finished solder wire in the receiving groove; Step 3, pouring the fluid carrier into the receiving tank, and stopping pouring after the fluid carrier submerges the solder wire; Step 4, cooling and solidifying the fluidized carrier to form the solid carrier; Step 5, using a blade to cut the solid carrier into short sections, the blade being perpendicular to the axis of the straightened solder wire; Step 6, heating the obtained short section, and taking out the solder column after the short section is melted.

[0018] Beneficial effects: The solder column prepared by the scheme of the present invention not only has a small length error, the length error can be controlled within ±0.01mm, and different solder columns produced in the same batch have uniform lengths, and the end surface flatness is good, and the end surface of the prepared solder column is almost perpendicular to its axis; the present invention has created a new method for preparing high-precision solder columns with extremely simple devices and processes, which not only has simple operating procedures and is easy to control, but also has low cost for manufacturing solder columns, and is suitable for large-scale industrial production; the solder columns manufactured by the scheme of the present invention do not need to use industrial solvents, and have the advantages of low pollution and good environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of a solder column production device for ceramic column grid array packaging in Example 1; Figure 2 is a schematic diagram of a top view of a receiving tank of a solder column production device in Example 1; Figure 3 is a schematic diagram of the receiving tank end of the solder column production device in Example 1; Figure 4 is a schematic cross-sectional view of the solder column production device in Example 1; Figure 5 It is a schematic diagram of the main direction of the solder column production device for ceramic column grid array packaging in Example 2; Figure 6 It is a schematic diagram of the main direction of the solder column production device for ceramic column grid array packaging in Example 3; Figure 7 It is a top-down schematic diagram of a solder column production device for ceramic column grid array packaging in Example 3; Figure 8 , Fig. 9 is a schematic cross-sectional view of the solder column production device in Examples 4 and 5; Fig.10 is a schematic diagram of the solder column (tin column) prepared in Example 1; Fig.11 is a schematic diagram of a solder column (tin column) prepared in Example 6; In the figure, 1 represents a receiving groove (substantially a receiving groove shell), 2 represents a carrier for embedding the finished solder wire, 3 represents the finished solder wire, 4 represents a clamp for fixing the finished solder wire, 5 represents an end cover, 6 represents an inner cavity of the receiving groove, 7 represents a seam on the side wall of the receiving groove, and 8 represents the cutting direction of the blade. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is further described in conjunction with the accompanying drawings, but the following embodiments are only used to help understand the principle and core idea of ​​the present invention, and are not intended to limit the scope of protection of the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, improvements made to the present invention also fall within the scope of protection of the claims of the present invention. Example 1

[0021] See also Figures 1 to 4 A solder column production device for ceramic column grid array packaging includes a tool for cutting solder columns and a receiving groove 1. A solid carrier for burying a finished solder wire 3 is provided in the inner cavity 6 of the receiving groove 1, and the finished solder wire 3 is built into and fixed in the solid carrier in a straightened state.

[0022] In this embodiment, the solid carrier is solid paraffin. Along the width direction of the receiving tank 1, the cross section of the receiving tank 1 is rectangular, and the width and height of the receiving tank 1 are both 25 mm. The receiving tank 1 is made of stainless steel material, and the bottom surface of the receiving tank 1 is a plane with a surface roughness of IT8 level, and the wall thickness of the receiving tank 1 is 5 mm.

[0023] In this embodiment, the side wall ( Figure 1 The main side wall and the rear side wall shown in the figure are provided with a slit 7 just enough for the blade of the cutter to enter and exit. The blade of the cutter is always perpendicular to the axis of the finished solder wire 3 after being stretched straight. The wall thickness of the blade is not more than 1mm, that is, the blade and the side wall of the slit 7 are matched with a small gap. The gap between the blade and the slit 7 is controlled within 0.005mm, and the low point of the slit 7 is lower than the position of the finished solder wire 3. The width between two adjacent slits 7 (the distance between the centers of two adjacent slits 7) is equal to the standard width of the solder column.

[0024] In this embodiment, the finished solder wire 3 passes through the circular holes at both ends of the receiving groove 1. The aperture of the circular holes is just enough for the finished solder wire 3 to pass through without causing the finished solder wire 3 to be squeezed. Both ends of the finished solder wire 3 are fixed on the clamp 4, and the clamp 4 is fixed on the outside of the receiving groove 1.

[0025] In this embodiment, a method for preparing a solder column (tin column) for a ceramic column grid array package comprises the following steps: Steps 1 and 2, straighten the finished tin wire (finished solder wire 3, the same below); the straightened finished tin wire is located in the receiving groove 1 (the segment to be cut is located in the receiving groove 1); specifically, the finished tin wire (with a diameter of 0.5 mm) is first passed through the round holes at both ends of the receiving groove 1, and then the finished tin wire 3 is straightened and fixed on the clamp 4, so that the straightness of the straightened tin wire is not less than 0.01 mm / m; Step 3, first use a high temperature resistant tape (Teflon tape) to seal the seam 7 of the side wall of the receiving tank 1, and then pour the melted paraffin into the receiving tank 1, the temperature of the melted paraffin is controlled to be 110°C, and the pouring is stopped after the paraffin submerges the tin wire. At this time, the straightened tin wire is built into the middle of the paraffin body; when pouring the melted paraffin, pour it from the side of the tin wire, and the fluid paraffin should not fall directly on the tin wire; Step 4, waiting for the fluid paraffin to cool and solidify to form solid paraffin; Step 5, transfer the containing tank 1 with the solid paraffin and tin wire as a whole to the operating workshop at 15°C, tear off the high temperature resistant tape, check and adjust the blade for cutting the solid paraffin so that it is perpendicular to the axis of the stretched tin wire, and cut the solid paraffin into short sections (paraffin short sections). The cutting direction is as shown in Figure 1 As shown by the arrow 8, the standard length of the short section is 2.5 mm, and the cross section of the short section is as follows: Figure 4 As shown; Step 6, heating the obtained short section to 75° C., and taking out the tin column using tweezers or other tools after the short section is melted.

[0026] The tin column prepared in this embodiment is as follows Fig.10 As shown, the end face is straight when observed with the naked eye. The end face height difference (the size difference between different parts of the same end face of the tin column relative to the reference surface) is measured with the aid of an instrument (scanning electron microscope) of approximately 0.001-0.002mm, with an accuracy of micron level. The length of the tin column is 2.5mm±0.01mm. Example 2

[0027] A solder column production device for ceramic column grid array packaging, referring to Example 1 and as Figure 5 As shown, the difference from Example 1 is that the two ends of the receiving groove 1 are sealed with detachable end covers 5, the two ends of the finished solder wire 3 are fixed on the clamp 4, and the clamp 4 is fixed in the inner cavity of the receiving groove 1. Example 3

[0028] A solder column production device for ceramic column grid array packaging, referring to Example 1 and as Figure 6 and Figure 7 As shown, the difference from Example 1 is that: both ends of the receiving groove 1 are sealed with detachable end covers 5, both ends of the finished solder wire 3 are fixed on the clamp 4, the clamp 4 is fixed in the inner cavity of the receiving groove 1, and the side wall of the receiving groove 1 is not provided with a seam 7 and a high-temperature resistant tape; when implementing step 5 of the preparation method, the end covers 5 at both ends of the receiving groove 1 are first removed, and then the solid paraffin block is axially pushed out, and then cut into paraffin blocks according to the required length. Embodiment 4-5

[0029] A solder column production device for ceramic column grid array packaging, referring to Example 1 and as Figure 8and Fig. 9 As shown, the difference from the first embodiment is that the cross section of the receiving groove 1 is trapezoidal or U-shaped. Example 6

[0030] A solder column production device for ceramic column grid array packaging includes a tool for cutting solder columns and a receiving groove 1. A solid carrier for burying finished solder wire 3 is arranged in the inner cavity 6 of the receiving groove 1, and the finished solder wire 3 is built into and fixed in the solid carrier in a straightened state.

[0031] In this embodiment, the solid carrier is a glutinous rice block in a frozen state (freezing temperature is -15°C), and the glutinous rice block is formed by consolidating glutinous rice flour with a particle size not greater than 800 mesh (accounting for 80% of the total weight) and paste (the water content of which accounts for 10% of the total weight).

[0032] In this embodiment, along the width direction of the receiving groove 1, the cross section of the receiving groove 1 is U-shaped (see Fig. 9 As shown), the width and height of the receiving groove 1 are both 20 mm. The receiving groove 1 is made of stainless steel material, the bottom surface of the receiving groove 1 is a plane with a surface roughness of IT8, and the wall thickness of the receiving groove 1 is 5 mm.

[0033] In this embodiment, the side wall ( Figure 1 The main side wall and the rear side wall shown in the figure are provided with a slit 7 just enough for the blade of the cutter to enter and exit. The blade of the cutter is always perpendicular to the axis of the finished solder wire 3 after being stretched straight. The wall thickness of the blade is not more than 1mm, that is, the blade and the side wall of the slit 7 are matched with a small gap. The gap between the blade and the slit 7 is controlled within 0.005mm, and the low point of the slit 7 is lower than the position of the finished solder wire 3. The width between two adjacent slits 7 (the distance between the centers of two adjacent slits 7 is 2.2mm) is equal to the standard width of the solder column.

[0034] In this embodiment, the finished solder wire 3 passes through the circular holes at both ends of the receiving groove 1. The aperture of the circular holes is just enough for the finished solder wire 3 to pass through without causing the finished solder wire 3 to be squeezed. Both ends of the finished solder wire 3 are fixed on the clamp 4, and the clamp 4 is fixed on the outside of the receiving groove 1.

[0035] In this embodiment, a method for preparing a solder column (tin column) for a ceramic column grid array package comprises the following steps: Steps 1 and 2, straighten the finished tin wire; the straightened finished tin wire is located in the receiving groove 1 (referring to the segment to be cut is located in the receiving groove 1); specifically, the finished tin wire (with a diameter of 0.5 mm) is first passed through the round holes at both ends of the receiving groove 1, and then the finished tin wire 3 is straightened and fixed on the clamp 4, so that the straightness of the straightened tin wire is not less than 0.01 mm / m; Step 3, first use a high temperature resistant tape (Teflon tape) to seal the seam 7 of the side wall of the receiving tank 1, and then pour a fluid and evenly stirred carrier (i.e., a mixture of glutinous rice flour, paste and water) into the receiving tank 1, and stop pouring after the fluid mixture submerges the tin wire. At this time, the straightened tin wire is built into the middle of the fluid mixture; when pouring the fluid mixture, pour it from the side of the tin wire, and do not let the fluid mixture fall directly on the tin wire; Step 4, then quickly transfer the aforementioned holding tank 1 to an atmosphere of -15°C, and wait for the fluid mixture to cool and solidify to form a solid glutinous rice block; Step 5, tear off the high temperature resistant tape, check and adjust the blade for cutting the solid glutinous rice block so that it is perpendicular to the axis of the straightened tin wire, and cut the solid glutinous rice block into short sections (glutinous rice block short sections). For the cutting direction, refer to Figure 1 As shown by the middle arrow 8, the standard length of the short section is 2.2 mm; Step 6, transfer the obtained short section to an atmosphere of 20-35°C, remove the tin column after the short section is dissolved, clean it, dry it naturally, and package it.

[0036] The tin column prepared in this embodiment is as follows Fig.11 As shown, the end face is straight when observed with the naked eye. The end face height difference (the size difference between different parts of the same end face of the tin column relative to the reference surface) is measured with the aid of an instrument (scanning electron microscope) of approximately 0.0015-0.002mm, with an accuracy of micron level. The length of the tin column is 2.2mm±0.01mm. Example 7

[0037] A solder column (tin column) production device and method for ceramic column grid array packaging, referring to Example 6, the difference between it and Example 6 is that: the solid carrier is a flour block in a frozen state (freezing temperature is -20°C), and the flour block is formed by consolidating flour with a particle size of no more than 800 mesh (weight proportion is 60% of the total weight) and paste (water proportion is 15% of the total weight). The end face accuracy of the tin column produced by the scheme in the embodiment can also reach the micron level, and the length error is ±0.01mm.

[0038] In the above embodiment, the cutter blades may also be two parallel double-edged blades, the blade line spacing of the double-edged blades being equal to the standard width of the solder column. This solution allows the tin column to be directly cut out in a one-step cutting process.

Claims

1. A solder column production device for a ceramic column grid array package, comprising a cutter for cutting the solder column, characterized in that: The device further comprises a receiving groove (1), wherein a solid carrier for embedding the finished solder wire (3) is arranged in the inner cavity (6) of the receiving groove (1), and the finished solder wire (3) is embedded and fixed in the solid carrier in a straightened state.

2. The solder column production device for ceramic column grid array packaging according to claim 1, characterized in that: The solid carrier is solid paraffin.

3. The solder column production device for ceramic column grid array packaging according to claim 1, characterized in that: The solid carrier is a glutinous rice block or a flour block in a frozen state, the water content in the glutinous rice block or the flour block does not exceed 20% of its total weight, and the freezing temperature is not higher than -10°C.

4. The solder column production device for ceramic column grid array packaging according to claim 3, characterized in that: The glutinous rice block is formed by consolidating glutinous rice flour with a particle size not greater than 800 meshes and paste, and the flour block is formed by consolidating flour with a particle size not greater than 800 meshes and paste.

5. The solder column production device for ceramic column grid array packaging according to any one of claims 1 to 4, characterized in that: Along the width direction of the accommodating groove (1), the cross-section of the accommodating groove (1) is trapezoidal, arc-shaped, rectangular or U-shaped.

6. The solder column production device for ceramic column grid array packaging according to claim 5, characterized in that: A slit (7) is provided on the side wall of the accommodating groove (1) so as to allow a blade of a cutter to enter and exit, and the lowest point of the slit (7) is lower than the position of the finished solder wire (3).

7. The solder column production device for ceramic column grid array packaging according to claim 6, characterized in that: The width between two adjacent seams (7) is equal to the standard width of the solder column.

8. The solder column production device for ceramic column grid array packaging according to claim 7, characterized in that: Both ends of the receiving groove (1) are sealed with detachable end covers (5), and the seam (7) on the side wall of the receiving groove (1) is sealed with a detachable film or a high temperature resistant adhesive tape.

9. The solder column production device for ceramic column grid array packaging according to claim 8, characterized in that: Both ends of the finished solder wire (3) are fixed on a clamp (4), and the clamp (4) is fixed on the outside or the inner cavity (6) of the receiving groove (1).

10. The method for preparing a solder column of the device according to claim 1, characterized in that the steps include: Step 1, straightening the prepared finished solder wire; Step 2, placing and fixing the straightened solder wire in the receiving groove (1); Step 3, pouring the fluid carrier into the receiving tank, and stopping pouring after the fluid carrier submerges the solder wire; Step 4, cooling and solidifying the fluidized carrier to form the solid carrier; Step 5, using a blade to cut the solid carrier into short sections, the blade being perpendicular to the axis of the straightened solder wire; Step 6, heating the obtained short section, and taking out the solder column after the short section is melted.

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