Solder ball printing device

Abstract

The invention provides a solder ball printing device, which can efficiently and reliably fill / print solder ball, and form a bump. The solder ball printing device of the invention comprises a flux printing part for printing flux on an electrode pad of a substrate; a solder ball filling / printing part for providing solder ball on the electrode printed with the flux; and a check / repair part for checking the condition of the substrate printed with the solder ball and repairing according to bad condition. A flux checking / repairing part, for checking the condition of the substrate printed with the flux and repairing according to bad condition, is arranged between the flux printing part and the solder ball filling / printing part, while the solder ball filling / printing part comprises a printing unit having a mesh for providing solder ball for the substrate and a slit-like body for filling solder ball to the mesh.

Description

technical field [0001] The invention relates to a screen printing device, in particular to a solder ball printing device for printing solder balls on the surface of a substrate. Background technique [0002] In the formation of spherical bumps (50 μm to 100 μm in diameter) with a pitch of 100 to 180 μm, there is a printing method in which solder paste is printed and then reflowed to form solder balls using a known high-precision screen printing device. As an example of a screen printing apparatus, it includes: a substrate carrying in conveyor, a substrate carrying out conveyor, a table with a lifting mechanism, a mask with a transfer pattern as an opening, a squeegee, a squeegee lifting mechanism, and The scraper head of the horizontal movement device, and the control device for controlling these parts. [0003] After the substrate is carried into the device from the carry-in conveyor part, the substrate is temporarily positioned and fixed on the printing table part, and th...

AI Technical Summary

Problems solved by technology

However, since the printing method is difficult to ensure the uniformity of the transfer volume, the solder bumps after reflow are pressed by flattening and the height is smoothed, so there are problems in the number of steps and high equipment costs.

In addition, in the case of finerization such as 100 to 150 μm pitch along with the high density of devices, there are problems of poor printing yield and poor productivity.

[0009] On the other hand, the solder ball transfer method can form highly stable bumps by ensuring the classification accuracy of the solder balls. In the case of increased production tact, there is a problem that the cost of bump formation increases due to the increase in jig / equipment prices

[0010] In addition, in the method of shaking or vibrating the screen of Patent Document 1 to fill the predetermined openings with solder balls, as the diameter of the solder ball particles becomes smaller, adhesion phenomenon caused by van der Waals force or static electricity may occur. caused by the adsorption phenomenon, resulting in the problem that it cannot be filled into the opening of the mask

In addition, the same problem also exists in the filling with the translational movement of the scraper or brush, etc.

[0011] Furthermore, in the method of Patent Document 2, although a remedy can be performed, there is a high possibility that the amount of residual flux will decrease, and when the wettability of the solder is poor during batch reflow, even if the solder balls melt, it may occur Poor wetting due to incomplete welding of counter electrode pads

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