導(dǎo)通孔起線路互相連結(jié)導(dǎo)通的作用，電子行業(yè)的發(fā)展，同時也促進(jìn)FPC線路板乃至fpc軟硬結(jié)合板的發(fā)展，也對印制板制作工藝和表面貼裝技術(shù)提出更高要求。FPC線路板塞孔工藝應(yīng)運(yùn)而生，同時應(yīng)滿足下列要求：With the development of electronic industry, it also promotes the development of FPC circuit board and FPC hard and soft combination board. It also puts forward higher requirements for PCB manufacturing process and surface mount technology. The plug hole technology of FPC circuit board arises at the historic moment, which should meet the following requirements:

1. 導(dǎo)通孔內(nèi)有銅即可，阻焊可塞可不塞; The copper in the through hole is enough, and the resistance welding can be plugged or not;

2. 導(dǎo)通孔內(nèi)必須有錫鉛，有一定的厚度要求（4微米），不得有阻焊油墨入孔，造成孔內(nèi)藏錫珠；There must be tin and lead in the through hole, with a certain thickness requirement (4 microns), no solder resist ink into the hole, causing tin beads in the hole;

3. 導(dǎo)通孔必須有阻焊油墨塞孔，不透光，不得有錫圈，錫珠以及平整等要求。

隨著電子產(chǎn)品向“輕、薄、短、小”方向發(fā)展，fpc多層軟硬結(jié)合板也向高密度、高難度發(fā)展，因此出現(xiàn)大量SMT、BGA的FPC線路板，而客戶在貼裝元器件時要求塞孔，主要有以下五個作用：The through hole must have solder resist ink plug hole, not transparent, no tin ring, tin bead and leveling requirements.
With the development of electronic products in the direction of "light, thin, short and small", FPC multi-layer soft and hard boards are also developing to high density and high difficulty. Therefore, a large number of FPC circuit boards with SMT and BGA appear. Customers require plug holes when mounting components, which mainly have the following five functions:
①. 防止FPC線路板過波峰焊時錫從導(dǎo)通孔貫穿元件面造成短路；特別是我們把過孔放在BGA焊盤上時，就必須先做塞孔，再鍍金處理，便于BGA的焊接。

To prevent short circuit caused by tin penetrating through the element surface from the through hole during wave soldering of FPC circuit board; In particular, when we put vias on BGA pads, we must first plug the vias and then gild them to facilitate BGA welding.

②. 避免助焊劑殘留在導(dǎo)通孔內(nèi)；

Avoid flux remaining in the through hole;

③. 電子廠表面貼裝以及元件裝配完成后PCB在測試機(jī)上要吸真空形成負(fù)壓才完成：

After the surface mount and component assembly of the electronics factory, the PCB should be vacuumed on the testing machine to form a negative pressure

④. 防止表面錫膏流入孔內(nèi)造成虛焊，影響貼裝；

prevent the solder paste from flowing into the hole to cause false soldering and affect the mounting;

⑤. 防止過波峰焊時錫珠彈出，造成短路。

prevent solder bead from popping out during over wave soldering, resulting in short circuit.