Chip mounter

Abstract

The invention relates to the technical field of semiconductor packaging, in particular to a chip mounter, which comprises an adsorption mechanism provided with a suction head, the suction head is cylindrical and is provided with an air passage along the axial direction, the suction head is used for adsorbing a sheet, and the suction head is also communicated with a negative pressure air source to generate adsorption force for adsorbing the sheet; the driving mechanism is connected with the adsorption mechanism and used for driving the adsorption mechanism to move at least in the vertical direction and the horizontal direction; and when the driving mechanism moves the suction head on the adsorption mechanism to a set distance right above the sheet and the suction head is not in contact with the sheet, the negative pressure air source generates adsorption force for sucking up the sheet at the end part of the suction head. By means of the arrangement, force borne by a sheet in the suction process is smaller, the sheet is not prone to breakage, and due to the fact that the sheet does not make contact with the sheet before suction, compared with deformation contact of an existing flexible vacuum suction head, the precision is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor packaging, and in particular to a chip mounter. Background Art

[0002] With the continuous development of the semiconductor industry, the chip mounter has become a crucial equipment in the packaging production process. As the chip size continues to shrink and the integration continues to increase, the requirements for the accuracy, efficiency and reliability of the chip mounter are becoming higher and higher.

[0003] In the related art, the placement machine mostly picks up the thin sheet by means of a flexible vacuum suction head. When performing the specific adsorption operation, the flexible vacuum suction head is first moved to contact with the thin sheet, and then the thin sheet is squeezed by the flexible vacuum suction head to generate negative pressure between the flexible vacuum suction head and the thin sheet, thereby sucking up the thin sheet, and then the thin sheet is moved to the set position.

[0004] However, for some fragile thin sheets, the above extrusion method can easily cause the thin sheets to break; in addition, due to the deformation of the flexible vacuum suction head itself during the extrusion process, it can also easily cause the thin sheets to move, thereby affecting the accuracy of subsequent patching. Summary of the invention

[0005] In view of at least one of the above technical problems, the present invention provides a chip placement machine, which adopts structural improvement to improve the accuracy and reliability of chip placement.

[0006] According to a first aspect of the present invention, there is provided a chip mounter, comprising: The suction mechanism comprises a suction head, the suction head is cylindrical and has an air passage along the axial direction, the suction head is used to adsorb the sheet, and the suction head is also connected to a negative pressure air source to generate an adsorption force for adsorbing the sheet; A driving mechanism, connected to the adsorption mechanism, and used to drive the movement of the adsorption mechanism at least in the vertical and horizontal directions; When the driving mechanism moves the suction head on the adsorption mechanism to a set distance above the sheet without contact, the negative pressure air source generates an adsorption force at the end of the suction head to suck up the sheet.

[0007] In some embodiments of the present invention, the set distance ranges from 0.1 mm to 0.2 mm.

[0008] In some embodiments of the present invention, the suction head is made of POM material.

[0009] In some embodiments of the present invention, the suction head is provided in plurality, and the adsorption mechanism further comprises a tube column, a fixing plate and a tube joint; The fixing plate has an air cavity inside, one end of the tube column is connected with the suction head, and the other end extends into the air cavity, the pipe joint is connected with the air cavity, and the tube column has an air hole connected with the air cavity.

[0010] In some embodiments of the present invention, the adsorption mechanism further includes a limiting plate, the limiting plate is parallel to and attached to the fixing plate, and the air cavity is formed between the fixing plate and the limiting plate.

[0011] In some embodiments of the present invention, the end of the tube column away from the pipette head further comprises a limiting cover, and the diameter of the limiting cover is greater than the diameter of the tube column; The limiting plate is provided with a limiting hole matched with the limiting cover.

[0012] In some embodiments of the present invention, a buffer pressure-maintaining mechanism is further included, and the buffer pressure-maintaining mechanism is connected to the tube column to provide elastic pressure in the direction from the tube column to the suction head.

[0013] In some embodiments of the present invention, the elastic pressure of the buffer pressure-maintaining mechanism can be adjusted.

[0014] In some embodiments of the present invention, the buffer pressure-maintaining mechanism includes an adjustment plate, an adjustment screw, and a compression spring; The adjusting plate is provided with an adjusting hole for the adjusting screw to be screwed, the adjusting hole is arranged corresponding to the limiting hole, one end of the compression spring is in contact with the limiting cover, and the other end is in contact with the adjusting screw.

[0015] In some embodiments of the present invention, a linear bearing is also fixed on the fixing plate, and the pipe column can be relatively slidably connected in the linear bearing.

[0016] The beneficial effects of the present invention are as follows: the present invention arranges a suction head on the suction mechanism so that the suction head can suck up the thin sheet through the negative pressure airflow generated by the negative pressure air source at a position close to the thin sheet but not in contact with it. Compared with the method in the prior art of first pressing down and squeezing and then sucking up by the flexible vacuum suction head, the thin sheet is subjected to less force during the suction process and is not prone to rupture. Moreover, since the thin sheet is not in contact with the suction head before suction, the accuracy is higher than the deformation contact of the existing flexible vacuum suction head. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of a chip mounter in an embodiment of the present invention (the driving mechanism is omitted); Figure 2 In the embodiment of the present invention Figure 1 A local enlarged view of point A in FIG. Figure 3 This is a schematic diagram of the connection structure between the pipette tip and the pipe column in an embodiment of the present invention; Figure 4 is a top view of the adsorption mechanism in an embodiment of the present invention; Figure 5 In the embodiment of the present invention Figure 4 BB section view in the figure; Figure 6 In the embodiment of the present invention Figure 4 CC section view in the figure; Figure 7 This is a schematic diagram of the connection structure of the suction head, the pipe column, the spring and the adjusting screw in an embodiment of the present invention; Figure 8 Schematic diagram of the principle of pressure holding pressure adjustment in an embodiment of the present invention.

[0019] Explanation of the accompanying drawings: 1. adsorption mechanism; 11. suction head; 11a. air duct; 12. pipe column; 12a. air vent; 12b. limit cover; 13. fixing plate; 13a. air cavity; 14. pipe joint; 15. limit plate; 15a. step hole; 16. buffer pressure maintaining mechanism; 16a. adjustment plate; 16b. adjustment screw; 16c. compression spring; 17. linear bearing; 01. piezoelectric ceramics; 02. aluminum shell. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0021] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0023] like Figure 1 to Figure 2 The chip mounter shown in the figure includes an adsorption mechanism 1 and a driving mechanism (not shown in the figure). In some embodiments of the present invention, Figure 1 As shown in , the adsorption mechanism 1 has a suction head 11, which is cylindrical and has an air passage 11a along the axial direction. The suction head 11 is used to adsorb the thin sheet, and the suction head 11 is also connected to a negative pressure air source to generate an adsorption force for adsorbing the thin sheet; it should be pointed out here that in some embodiments of the present invention, the air passage 11a is arranged at the axis of the cylindrical suction head 11, and the diameter of the air passage 11a is much smaller than the diameter of the end face of the cylindrical suction head 11, so that a greater adsorption force can be provided while increasing the contact area with the thin sheet to reduce the force on the thin sheet. In the embodiments of the present invention, the number of air passages 11a is not limited to a single one, and those skilled in the art can also set a plurality of them as needed.

[0024] The driving mechanism is connected to the adsorption mechanism 1, and is used to drive the movement of the adsorption mechanism 1 at least in the vertical and horizontal directions; it should be noted that in the embodiments of the present invention, the driving mechanism has various forms, for example, it can be a stepper motor driving a lead screw, a rack or a synchronous belt to achieve movement in at least three axes, or a multi-axis robot can be used to achieve the adsorption and movement of the sheet. Of course, it should be noted that in one embodiment of the present invention, such as Figure 2 In the figure, the thin sheet is a piezoelectric ceramic 01, which is adsorbed by the suction head 11 on the adsorption mechanism 1, and then pressed into the aluminum shell 02 of the buzzer by the driving mechanism. Of course, it should be pointed out here that the functions of adsorbing, transporting and pasting thin sheets can be applied to a variety of production scenarios, and the specific application scenarios will not be introduced in detail here.

[0025] When the adsorption is performed, when the driving mechanism moves the suction head 11 on the adsorption mechanism 1 to a set distance above the sheet without contacting it, the negative pressure air source generates an adsorption force at the end of the suction head 11 to suck up the sheet. It should be pointed out here that in the embodiment of the present invention, the specific set distance that the suction head 11 moves to above the sheet needs to be set according to the size of the sheet and the adsorption force of the negative pressure source. Since the method in the embodiment of the present invention does not contact the sheet before adsorption, the deviation caused by deformation is reduced, and the accuracy of adsorption and patching is improved; on the other hand, due to the method of adsorption through negative pressure airflow, the force on the sheet is reduced, thereby reducing the breakage of the sheet and improving the reliability of the sheet during adsorption, movement, and patching.

[0026] In the above embodiment, by setting the suction head 11 on the suction mechanism 1, the suction head 11 sucks the thin sheet through the negative pressure airflow generated by the negative pressure air source at a position close to the thin sheet and not in contact with it. Compared with the method in the prior art where the flexible vacuum suction head 11 first presses down and squeezes and then sucks up, the thin sheet is subjected to less force during the suction process and is not easily broken. In addition, since there is no contact with the thin sheet before suction, the accuracy is higher than the deformation contact of the existing flexible vacuum suction head 11.

[0027] On the basis of the above embodiments, in some embodiments of the present invention, when the piezoelectric ceramic 01 is adsorbed, the distance is set in the range of 0.1mm~0.2mm. In some embodiments of the present invention, Figure 2 As shown in , when the suction head 11 moves to 0.15 mm above the piezoelectric ceramic 01, the negative pressure air source is turned on to generate a negative pressure adsorption airflow, thereby realizing the function of sucking up the piezoelectric ceramic 01. In addition, in an embodiment of the present invention, in order to further improve the accuracy during suction, the suction head 11 is set to a hard material, such as POM material. POM material is polyoxymethylene, which has excellent mechanical strength and rigidity, and good wear resistance. This setting can avoid deformation of the suction head 11, thereby further improving the accuracy of the piezoelectric ceramic 01 and avoiding its deviation during the adsorption process.

[0028] Optionally, in order to further improve the efficiency of the patch, in some embodiments of the present invention, the suction head 11 is provided with a plurality of suction heads, and the suction mechanism 1 further includes a column 12, a fixing plate 13 and a pipe joint 14; Figures 3 to 6As shown in the figure, the fixed plate 13 has an air cavity 13a, one end of the pipe column 12 is connected to the suction head 11, and the other end extends into the air cavity 13a, the pipe joint 14 is connected to the air cavity 13a, and the pipe column 12 has a vent hole 12a connected to the air cavity 13a. Through the setting of the fixed plate 13, multiple pipe columns 12 can be set to be connected to the air cavity 13a at the same time, so that when the pipe joint 14 is connected to the negative pressure air source, negative pressure is generated in the entire air cavity 13a, so that under the action of the vent hole 12a, multiple suction heads 11 connected to the pipe column 12 all generate negative pressure airflow. Figure 5 As shown in , through the arrangement of this structural form, multiple sheets can be sucked synchronously, thereby improving the efficiency of patching.

[0029] In the embodiment of the present invention, the formation method of the air cavity 13a is as follows: Figure 5 and Figure 6 As shown in , the adsorption mechanism 1 further includes a limiting plate 15, which is parallel to the fixed plate 13, and the air cavity 13a is formed between the fixed plate 13 and the limiting plate 15. Specifically, a groove may be provided on the surface of the fixed plate 13 facing the limiting plate 15, or a groove may be provided on the surface of the limiting plate 15 facing the fixed plate 13, or grooves may be provided on both opposite surfaces to form the air cavity 13a; through the setting of this structural form, the structure is simple and easy to manufacture; the connection between the limiting plate 15 and the fixed plate 13 may be fixed by fasteners, or may be achieved by welding or snap-fitting.

[0030] Optionally, there are various fixing structures of the pipe column 12 in the embodiments of the present invention, such as Figure 3 and Figure 6 As shown in the figure, the end of the pipe column 12 away from the suction head 11 is also provided with a limit cover 12b, and the diameter of the limit cover 12b is larger than the diameter of the pipe column 12; the limit plate 15 is provided with a limit hole adapted to the limit cover 12b. Through the setting of the limit hole and the limit cover 12b, the limit plate 15 can limit the position of the pipe column 12. Specifically, the limit cover 12b can be abutted in the limit hole to fix the pipe column 12. There are many specific abutment methods, such as plugging or directly fixing with bolts.

[0031] In the embodiment of the present invention, in order to further reduce the damage to the sheet during adsorption or patching, as Figure 6 and Figure 7As shown in , it also includes a buffer pressure-maintaining mechanism 16, which is connected to the pipe column 12 to provide elastic pressure in the direction from the pipe column 12 to the suction head 11. Of course, it should be pointed out here that the buffer pressure-maintaining mechanism 16 has a variety of structural forms, for example, elastic parts can be used to achieve buffering of the pipe column 12, or it can be achieved by compressed gas, or it can also be achieved in the form of elastic airbags. In one embodiment of the present invention, the buffer pressure-maintaining mechanism 16 includes an adjustment plate 16a, an adjustment screw 16b and a compression spring 16c; the adjustment plate 16a has an adjustment hole for the adjustment screw 16b to be screwed, and the adjustment hole is corresponding to the limit hole. One end of the compression spring 16c abuts against the limit cover 12b, and the other end abuts against the adjustment screw 16b. Through such an arrangement, the suction head 11 has a buffer function of a certain distance following the tube column 12 in the vertical direction. When the negative pressure airflow sucks up the sheet and the sheet blocks the suction head 11, an upward force is generated due to the sudden blockage of the negative pressure airflow. The compression spring 16c is arranged so that the suction head 11 can move upward as a whole, thereby reducing the force on the sheet and improving the protection effect on the sheet.

[0032] In addition, in the embodiment of the present invention, the above-mentioned buffer pressure-maintaining mechanism 16 can also play a role in maintaining pressure during patching. Taking the patching process of the piezoelectric ceramic 01 as an example, after the patch is placed in the aluminum shell 02, it is necessary to generate a certain pressure on the piezoelectric ceramic 01 after the patch to ensure the stability of the bonding during the glue curing process. The pressure of maintaining pressure is provided by the compression spring 16c. In order to ensure that the pressure generated by multiple suction heads 11 during pressure maintenance is the same, in the embodiment of the present invention, the elastic pressure of the buffer pressure-maintaining mechanism 16 can be adjusted. Specifically, Figure 8 As shown in , during assembly, a dynamometer is used to test whether the pressure of each suction head 11 is the same. If not, the compression amount of the compression spring 16c is adjusted by rotating the adjustment screw, that is, the pressure of the compression spring 16c in the working state is adjusted to ensure that the pressure of each suction head 11 is the same. It should be pointed out here that in the embodiment of the present invention, since the diameter of the air channel 11a on the suction head 11 is smaller than the diameter of the end face of the suction head 11, the suction head 11 can adsorb the thin sheet, and after the adsorption is completed, the end face of the suction head 11 can also be used as a pressure head to apply pressure and maintain pressure on the thin sheet. Through the setting of this structural form, the two functions of adsorption and patch can be completed by the adsorption mechanism 1, and due to the above-mentioned improvements, the accuracy of the patch is further guaranteed.

[0033] In addition, in the embodiment of the present invention, in order to better protect the thin sheet during adsorption and provide a more uniform pressure holding pressure, the buffer pressure holding mechanism 16 is provided. Figure 6 and Figure 7As shown in , a linear bearing 17 is also fixed on the fixed plate 13, and the pipe column 12 can be relatively slidably connected in the linear bearing 17. In one embodiment of the present invention, the material of the pipe column 12 can be a copper tube, and the linear bearing 17 can adopt a solid inlaid lubricating bearing, that is, graphite or other additives are inlaid on the basis of a metal sleeve. This kind of solid inlaid lubricating bearing breaks through the limitation of general bearings relying on oil film lubrication. In the process of the pipe column 12 moving up and down, the solid lubricant rubs against the pipe column 12 through friction, and has the mechanical properties of the traditional copper sleeve and the characteristics of oil-free lubrication. Through the setting of the linear bearing 17, the friction force when the pipe column 12 moves up and down is reduced, so that better buffering and more uniform pressure holding pressure can be provided. Of course, it should be pointed out here that due to the presence of the linear bearing 17, a certain amount of air leakage may occur during the specific adsorption, but under the premise of ensuring the adsorption force, moderate air leakage is allowed, and this kind of air leakage can also achieve a buffering effect to reduce damage to the thin sheet.

[0034] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A chip mounter, characterized in that: include: The suction mechanism comprises a suction head, the suction head is cylindrical and has an air passage along the axial direction, the suction head is used to adsorb the sheet, and the suction head is also connected to a negative pressure air source to generate an adsorption force for adsorbing the sheet; A driving mechanism, connected to the adsorption mechanism, and used to drive the movement of the adsorption mechanism at least in the vertical and horizontal directions; When the driving mechanism moves the suction head on the adsorption mechanism to a set distance above the sheet without contact, the negative pressure air source generates an adsorption force at the end of the suction head to suck up the sheet.

2. The chip mounter according to claim 1, characterized in that: The set distance ranges from 0.1 mm to 0.2 mm.

3. The chip mounter according to claim 2, characterized in that: The suction head is made of POM material.

4. The chip mounter according to claim 2, characterized in that: The suction heads are provided in plurality, and the adsorption mechanism further comprises a pipe column, a fixing plate and a pipe joint; The fixing plate has an air cavity inside, one end of the tube column is connected with the suction head, and the other end extends into the air cavity, the pipe joint is connected with the air cavity, and the tube column has an air hole connected with the air cavity.

5. The chip mounter according to claim 4, characterized in that: The adsorption mechanism further includes a limiting plate, which is parallel to and attached to the fixing plate, and the air cavity is formed between the fixing plate and the limiting plate.

6. The chip mounter according to claim 5, characterized in that: The end of the tube column away from the suction head is also provided with a limit cover, and the diameter of the limit cover is larger than the diameter of the tube column; The limiting plate is provided with a limiting hole matched with the limiting cover.

7. The chip mounter according to claim 6, characterized in that: It also includes a buffer pressure-maintaining mechanism, which is connected to the tube column and is used to provide elastic pressure in the direction from the tube column to the suction head.

8. The chip mounter according to claim 7, characterized in that: The elastic pressure of the buffer pressure-maintaining mechanism can be adjusted.

9. The chip mounter according to claim 7, characterized in that: The buffer pressure-maintaining mechanism comprises an adjusting plate, an adjusting screw and a compression spring; The adjusting plate is provided with an adjusting hole for the adjusting screw to be screwed, the adjusting hole is arranged corresponding to the limiting hole, one end of the compression spring abuts against the limiting cover, and the other end abuts against the adjusting screw.

10. The chip mounter according to claim 9, characterized in that: A linear bearing is also fixed on the fixing plate, and the pipe column can be relatively slidably connected in the linear bearing.

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