Method for making metalized half hole

Abstract

The invention introduces a method for making a metalized half hole. The method comprises the steps of filling the position of a metalized half hole to be machined of a printed board with tin in the production process of the printed board after completion of photosensitive resistance welding, milling the half hole according to the design requirements, and performing hot air leveling. As lead tin in the hole supports a copper layer in the hole, hole wall copper skin upwarp and burr residual problems of the metalized half hole after forming can be avoided effectively. Excess solder in the position of the metalized half hole is removed naturally in the process of hot air leveling. The cut of the metalized half hole is coated with solder to avoid copper bareness. The process is simple, lines are not easy to damage, control is easy, and the production efficiency and quality of metalized half hole circuit boards are improved.

Description

technical field [0001] The invention relates to the field of making special printed boards, in particular to a method for making metallized half holes. Background technique [0002] In the production of printed boards, some special requirements are often encountered. The metallized half hole is a special case. The metallized half hole is mainly used on the carrier board as a daughter board of the mother board. Through the metallized half hole and the mother board and The pins of the components are soldered together. [0003] The conventional method of making metallized half-holes in printed boards inevitably has problems such as burrs remaining and copper skin on the hole walls when forming metallized half-holes. In severe cases, the metallized half-hole walls may even fall off. Welding buried hidden dangers. Therefore, how to do a good job in metallized half-hole processing has always been one of the difficult problems that printed circuit board production is committed to...

AI Technical Summary

Problems solved by technology

However, the secondary drilling method not only doubles the drilling cost, but if the powder remaining in the half hole is not cleaned after the secondary drilling, it will have an adverse effect on the solder mask and surface treatment, and the film must be processed In order to prevent the solder resist from remaining in the semi-metallized hole; the drilling method after lead-tin plating requires careful operation, and a little carelessness can easily cause damage to the lead-tin corrosion layer and lead to product scrap; the ink plug hole method before milling the shape involves manufacturing Plug hole template, plug hole, baking and other operations, the ink needs to be removed after slot milling, the process is cumbersome

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