JP2015033843A - Paste printing device and paste printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paste printing device and a paste printing method that are capable of managing quality of printing substances and maintaining initial viscosity of a paste to not only prevent poor loading but also reduce process costs and improve printing efficiency and productivity.SOLUTION: A paste printing device 100 includes a squeegee 600 for printing a paste 300 on a printed circuit board 201, viscosity detection means 400 for detecting viscosity of the paste 300, and supply means 500 for supplying flux to the paste 300. The paste printing device 100 can control the supply of the flux to adjust the viscosity of the paste 300.

Description

  The present invention relates to a paste printing apparatus and a paste printing method.

  2. Description of the Related Art In recent years, flip chip (Flip Chip), in which a solder bump is formed on a PCB (Printed Circuit Board) and a device is connected to the solder bump, is increasing.

  In particular, in the case of a main board (CPU) and a graphics computing device that computes a large amount of data at high speed, the substrate and the device are replaced with the technology for connecting the substrate and the device using an existing gold wire (Au wire). The application of flip chips, in which the connection resistance is improved by connecting them with solder, has been increasing rapidly.

  Solder bumps formed on the substrate to connect the chip and the substrate are formed by printing solder paste on the substrate and reflowing the substrate, and then forming a fine solder ball (Solder Ball) on the substrate. It can be divided into a method of mounting and forming, and a method of injecting molten solder directly into a substrate or using a mask. The solder bumps formed on the substrate in this way are melted and bonded to the metal for connection with copper (Cu) formed on the chip.

  As such a solder paste application method, screen printing is generally widely used, and this screen printing is performed by a solder paste application device. In the screen printing, a solder paste supplied on a metal mask in which openings of a specific pattern are formed is pressed with a squeegee blade and applied to a component mounting surface of a printed circuit board.

Japanese Patent Laid-Open No. 11-254641 Taiwan Registered Patent No. I293272

  An object of the present invention is to provide a paste printing apparatus and a paste printing method capable of continuously monitoring the viscosity of a paste by providing the paste printing apparatus with viscosity detecting means.

  Another object of the present invention is to provide flux and paste supply means in the paste printing apparatus so that the initial viscosity of the paste is maintained by replenishing the printing substance when the viscosity of the paste increases. Another object of the present invention is to provide a paste printing apparatus and a paste printing method.

  Still another object of the present invention is to provide a paste printing apparatus and a paste printing method in which printing efficiency is improved by using two or more squeegees.

  A paste printing apparatus according to an embodiment of the present invention includes a squeegee for printing a paste on a printed circuit board, a viscosity detection unit that detects the viscosity of the paste, and a supply unit that supplies flux to the paste. The viscosity of the paste can be adjusted by controlling the supply of the flux.

  Here, the viscosity detecting means can measure the viscosity of the paste using a rotational resistance.

  Further, the viscosity detecting means is movable in the vertical direction with respect to the printing direction.

  Further, the supply means can selectively supply flux, solder paste, or both according to the detection result of the viscosity detection means.

  The supply means is movable in the vertical direction with respect to the printing direction.

  The squeegee includes two or more squeegees, and each squeegee can be driven independently.

  The squeegee is movable in the printing direction.

  The squeegee can be adjusted in angle.

  A paste printing method according to an embodiment of the present invention includes a step of placing a printed circuit board on a printing table, a step of forming a mask on the upper part of the printed circuit board, and an upper portion of the mask using viscosity detecting means. A step of measuring a viscosity, a step of selectively supplying a printing substance including a flux and a paste from a supply unit provided on a rear surface of the viscosity detection unit according to the measured viscosity detection result; Sliding the squeegee provided on the rear surface in the printing direction and printing the paste on the printed circuit board.

  Here, when the printed circuit board is placed on the printing table, the printed circuit board can be vacuum-sucked and aligned with the printing table.

  The mask may be a resist pattern or a metal mask.

  In addition, in the step of measuring the viscosity of the paste, the viscosity of the paste on the printed circuit board can be measured using a rotational resistance.

  Further, at the stage of supplying the printing substance, flux, paste, or both can be selectively supplied according to the detection result of the viscosity detecting means.

  Further, the viscosity detecting means is movable in the vertical direction with respect to the printing direction.

  The supply means is movable in the vertical direction with respect to the printing direction.

  The squeegee includes two or more squeegees, and each squeegee can be driven independently.

  The squeegee is movable in the printing direction.

  The squeegee can be adjusted in angle.

  The paste printing apparatus and paste printing method according to the present invention can manage the quality of the printing substance by continuously monitoring the viscosity of the paste using the viscosity detecting means.

  Further, by supplying flux or paste from the supply means according to the detection result of the viscosity detection means, the initial viscosity of the paste can be maintained, and there is an effect of preventing poor filling.

  At this time, by supplying the flux or paste from the supply means and maintaining the appropriate viscosity of the paste, there is an effect that the disposal problem due to the paste which is high in viscosity and not rolled as before is reduced, and the process cost is reduced. .

  Also, the use of two or more squeegees has the effect of improving printing efficiency, reducing manufacturing time, and improving productivity.

1 is a cross-sectional view schematically illustrating a configuration of a paste printing apparatus according to an embodiment of the present invention. 3 is a flowchart schematically illustrating a printing method of a paste printing apparatus according to an embodiment of the present invention. 3 is a linear motion guide diagram schematically illustrating a driving method of a paste printing apparatus according to an embodiment of the present invention;

  Objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments with reference to the accompanying drawings. In this specification, it should be noted that when adding reference numerals to the components of each drawing, the same components are given the same number as much as possible even if they are shown in different drawings. I must. The terms “one side”, “other side”, “first”, “second” and the like are used to distinguish one component from another component, and the component is the term It is not limited by. Hereinafter, in describing the present invention, detailed descriptions of known techniques that may obscure the subject matter of the present invention are omitted.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

(Paste printing device)
FIG. 1 is a cross-sectional view schematically illustrating a configuration of a paste printing apparatus 100 according to an embodiment of the present invention.

  FIG. 3 is a linear motion guide diagram schematically illustrating a driving method of the paste printing apparatus 100 according to an embodiment of the present invention.

  Referring to FIG. 1, a paste printing apparatus 100 according to an embodiment of the present invention includes a squeegee 600 for printing a paste 300 on a printed circuit board 201, a viscosity detection unit 400 that detects the viscosity of the paste 300, Supply means 500 for supplying the flux to the paste 300, and controlling the supply of the flux to adjust the viscosity of the paste 300.

  The viscosity detecting unit 400 is a rotary viscometer, and measures the viscosity by rotating a spindle, so that the viscosity of a substance whose viscosity changes over time or when the viscosity changes over time. This is useful when measuring

  Referring to FIG. 3, the viscosity detection unit 400 can move in the vertical direction A with respect to the printing direction B, which matches the movement direction of the supply unit 500.

  The printing apparatus according to the present invention is capable of continuously monitoring the viscosity of the paste 300 using the viscosity detecting means 400, which is advantageous in managing print quality.

  The supply unit 500 selectively supplies the flux, the paste 300, or both according to the detection result of the viscosity detection unit 400.

  For example, when the viscosity increases, the flux and paste 300 are replenished so that the initial viscosity is maintained.

  Here, the supply unit 500 can move in the vertical direction A with respect to the printing direction B, which coincides with the moving direction of the viscosity detection unit 400.

  The printing apparatus 100 according to the present invention can maintain an appropriate viscosity by replenishing the flux and the paste 300 using the supply unit 500 when the viscosity of the paste increases, and the viscosity is high as in the past. The problem of product disposal due to the non-rolling paste 300 is reduced, and the process cost is reduced.

  The squeegee 600 serves to bump-print the paste 300 on the printed circuit board 201 and includes two or more squeegees 600.

  Each squeegee 600 is driven independently and can move in the printing direction B. In addition, the squeegee 600 can adjust the angle.

(Paste printing method)
FIG. 2 is a flowchart schematically showing a printing method of the paste printing apparatus 100 according to an embodiment of the present invention.

  FIG. 3 is a linear motion guide diagram schematically illustrating a driving method of the paste printing apparatus 100 according to an embodiment of the present invention.

  According to an embodiment of the present invention, a paste printing method includes: placing a printed circuit board 201 on a printing table 200; forming a mask 202 on the printed circuit board 201; and detecting viscosity at an upper part of the mask 202. A step of measuring the viscosity of the paste 300 using the means 400, and a printing substance containing the flux and the paste 300 is selected from the supply means 500 provided on the rear surface of the viscosity detecting means 400 according to the measured viscosity detection result. And a step of sliding the squeegee 600 provided on the rear surface of the supply means 500 in the printing direction B and printing the paste 300 on the printed circuit board 201.

  At this time, when the printed circuit board 201 is placed on the printed table 200, the printed circuit board 201 is vacuum-sucked and aligned with the printed table 200.

  In addition, in the step of forming the mask 202, the mask 202 may be a resist pattern or a metal mask.

  When the mask 202 is a resist pattern, the step of forming the mask 202 includes laminating a resist on a base substrate, and forming a bump forming hole corresponding to a bump forming opening in the resist to form the connection pad. Exposing.

  Here, the bump forming hole may be formed by a photolithography method including exposure and development, and the resist may be a dry film (DF).

  The printed circuit board 201 is a circuit board in which one or more circuits including connection pads are formed on an insulating layer, and may be a multilayer printed circuit board.

  As the insulating layer, a resin insulating layer can be used. As the resin insulating layer, a thermosetting resin such as an epoxy resin, a thermoplastic resin such as polyimide, or a resin impregnated with a reinforcing material such as glass fiber or inorganic filler, for example, a prepreg can be used. A thermosetting resin and / or a photocurable resin can be used, but is not particularly limited thereto.

  The circuit including the connection pads can be applied without limitation as long as it is used as a conductive metal for circuits in the circuit board field, and copper is generally used in a printed circuit board.

  The step of measuring the viscosity may be performed by a method in which the spindle of the viscosity detecting unit 400 is rotated and the viscosity resistance of the paste 300 on the printed circuit board 201 is measured.

  In the supplying step, the flux, the paste 300, or both are selectively supplied from the supply unit 500 according to the detection result of the viscosity detection unit 400.

  Referring to FIG. 2, the printed circuit board 201 is loaded into the printing apparatus 100 after the start stage of driving the device.

  Next, the viscosity of the paste is measured on the basis of one lot by the viscosity detecting means 400, and the increase in viscosity is continuously monitored.

  At this time, if the rate of increase in the viscosity of the paste 300 is 10% or more, the flux or paste 300 is additionally supplied from the supply means 500.

  At this time, if the viscosity detection means 400 continuously measures the viscosity of the paste and the additional supply from the supply means 500 is still high, the flux or paste 300 can be additionally supplied regardless of the number of times. .

  When measuring the viscosity, if the rate of increase in the viscosity of the paste 300 is less than 10%, a drive system is started to start printing as it is.

  As described above, when the quality of the printing material is managed using the viscosity detection unit 400 and the supply unit 500, the amount of the paste 300 to be discarded can be reduced, which has an effect of reducing the process cost.

  In order to explain in more detail, compared with the conventional method, for example, conventionally, 60 panels were printed with 500 g of paste 300. When many panels were printed at once, the viscosity increased over time and the unrolled paste 300 had to be discarded.

  However, since the printing apparatus 100 of the present invention is provided with the viscosity detection means 400 and the supply means 500, 30 panels are printed with the same amount of 500 g of paste 300.

  Thereafter, the viscosity is measured by the viscosity detecting means 400 and compared with the initial viscosity to check whether the viscosity has increased by 10% or more.

  When the increase rate of the viscosity of the paste is 10% or less with respect to the initial viscosity, printing of 30 panels is started, and when it is 10% or more, the flux and the paste 300 are replenished.

  The process of measuring the viscosity and spraying with the supply means 500 is repeated about 1 to 6 times, and printing is performed in the initial viscosity state.

  At this time, since 300 g of paste 300 is reduced when printing 120 panels, the above method can be further repeated after replenishing 300 g manually.

  When the viscosity of the paste 300 is too high, it becomes difficult to roll, and when the viscosity is too low, there is a problem that the paste 300 spreads, so that printing becomes difficult.

  Therefore, the viscosity of the paste 300 is 90 to 200 Pa.s. It is preferable to print with s (pascal).

  The above content is an example in which the printing method of the present invention and the conventional method are roughly compared, and the amount of paste 300, the number of panels, the viscosity reference value, and the number of repetitions of the process are not limited thereto.

  FIG. 3 is a linear motion guide drawing of the apparatus schematically showing a driving method of the paste printing apparatus 100 according to an embodiment of the present invention.

  1 and 3, the linear motion guide module 101 of the paste printing apparatus 100 can be seen at a glance.

  After the printed circuit board 201 is placed on the printing table 200 by vacuum suction, the viscosity of the paste is measured and monitored by the viscosity detecting means 400.

  Depending on the detection result of the viscosity detection means 400, the printing material containing the flux, the paste 300, or both is supplied from the supply means 500.

  If the viscosity of the paste is not high, the squeegee 600 is driven to start printing.

  Here, in the linear motion guide module 101, it can be seen that the motion detection directions of the viscosity detection unit 400 and the supply unit 500 are the same, and the motion direction of the squeegee 600 is different.

  The viscosity detection means module 401 can move in the vertical direction A with respect to the printing direction B, which coincides with the movement direction of the supply means module 501.

  The supply unit module 501 can move in the vertical direction A with respect to the printing direction B, which coincides with the movement direction of the viscosity detection unit module 401.

  The squeegee module 601 can move in the printing direction B.

  The paste printing method according to the present invention can manage the quality of the printing substance by continuously monitoring the viscosity of the paste 300 using the viscosity detecting means 400.

  Further, by supplying the flux or paste 300 from the supply means 500 according to the detection result of the viscosity detection means 400, the initial viscosity of the paste can be maintained, and there is an effect of preventing poor filling.

  At this time, by supplying the flux or paste 300 from the supply means 500 and maintaining a suitable viscosity of the paste, the disposal problem due to the paste 300 having a high viscosity and not being rolled is reduced, and the process cost is reduced. effective.

  Further, the use of two or more squeegees 600 has the effect of improving printing efficiency, reducing manufacturing time, and improving productivity.

  As described above, the present invention has been described in detail based on the specific embodiments. However, the present invention is only for explaining the present invention, and the present invention is not limited thereto. It will be apparent to those skilled in the art that modifications and improvements within the technical idea of the present invention are possible.

  All simple variations and modifications of the present invention belong to the scope of the present invention, and the specific scope of protection of the present invention will be apparent from the appended claims.

  The present invention is applicable to a paste printing apparatus and a paste printing method.

DESCRIPTION OF SYMBOLS 100 Paste printing apparatus 101 Linear motion guide module 200 Printing table 201 Printed circuit board 202 Mask 300 Paste 400 Viscosity detection means 401 Viscosity detection means module 500 Supply means 501 Supply means module 600 Squeegee 601 Squeegee module A Vertical direction B Printing direction

Claims (18)

A squeegee for printing paste on a printed circuit board;
Viscosity detecting means for detecting the viscosity of the paste;
Supply means for supplying a flux to the paste,
A paste printing apparatus capable of adjusting the viscosity of the paste by controlling the supply of the flux.   The paste printing apparatus according to claim 1, wherein the viscosity detection unit measures the viscosity of the paste using a rotational resistance.   The paste printing apparatus according to claim 1, wherein the viscosity detection unit is movable in a vertical direction with respect to a printing direction.   The paste printing apparatus according to claim 1, wherein the supply unit selectively supplies a flux, a paste, or both according to a detection result of the viscosity detection unit.   The paste printing apparatus according to claim 1, wherein the supply unit is movable in a vertical direction with respect to a printing direction.   The paste printing apparatus according to claim 1, wherein the squeegee includes two or more squeegees, and each squeegee is driven independently.   The paste printing apparatus according to claim 1, wherein the squeegee is movable in a printing direction.   The paste printing apparatus according to claim 1, wherein the squeegee is adjustable in angle. Placing the printed circuit board on the printing table;
Forming a mask on the printed circuit board;
Measuring the viscosity of the paste at the top of the mask using viscosity detection means;
According to the measured viscosity detection result, selectively supplying a printing substance containing flux and paste from a supply means provided on the rear surface of the viscosity detection means;
Sliding the squeegee provided on the rear surface of the supply means in the printing direction to print the paste on the printed circuit board.   The paste printing method according to claim 9, wherein the printed circuit board is vacuum-sucked and aligned with the print table in the stage of placing the printed circuit board on the print table.   The paste printing method according to claim 9, wherein the mask is a resist pattern or a metal mask.   The paste printing method according to claim 9, wherein in the step of measuring the viscosity of the paste, the viscosity of the paste on the printed circuit board is measured using a rotational resistance.   The paste printing method according to claim 9, wherein in the step of supplying the printing substance, a flux, a paste, or both are selectively supplied according to a detection result of the viscosity detection unit.   The paste printing method according to claim 9, wherein the viscosity detection unit is movable in a vertical direction with respect to a printing direction.   The paste printing method according to claim 9, wherein the supply unit is movable in a vertical direction with respect to a printing direction.   The paste printing method according to claim 9, wherein the squeegee includes two or more squeegees, and each squeegee is driven independently.   The paste printing method according to claim 9, wherein the squeegee is movable in a printing direction.   The paste printing method according to claim 9, wherein the squeegee is adjustable in angle.

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