A kind of process method of double-sided encapsulation

Abstract

The invention relates to a double-sided encapsulation method, the method comprising the following steps: Step 1, mounting components or chips on the front of the substrate; Step 2, encapsulating the front of the substrate; Step 3, mounting components on the back of the substrate or chips; Step 4, encapsulate the balls on the back of the substrate through the encapsulation mold; Step 5, complete the encapsulation, raise the encapsulation mold, perform reflow soldering and post-curing; Step 6, cut into individual products. The invention discloses a double-sided encapsulation process, which can simultaneously plant balls and encapsulate, thereby simplifying the process flow and improving production efficiency.

Description

technical field [0001] The invention relates to a process method for double-sided packaging, which belongs to the technical field of semiconductor packaging. Background technique [0002] With the development of technology, double-sided packaging (more saving the internal space of the mobile phone) has become a trend. The existing process flow on the back of the double-sided packaging is to first plant the ball and then encapsulate it. The ball is exposed through thinning and laser drilling, and then through The reflow ball is formed and then connected to the final PCB board. The specific process is as follows: [0003] Step 1. Mount components or chips on the front side of the substrate; [0004] Step 2. Encapsulate the front of the substrate to protect components or chips; [0005] Step 3: Carry out ball planting on the back of the substrate, and then reflow soldering; then mount components on the back of the substrate; [0006] Step 4, encapsulate the back of the subst...

AI Technical Summary

Problems solved by technology

[0012] 1. When performing laser operations on the entire substrate, it is difficult to accurately adjust the offset of the laser position due to the different degrees of expansion and contraction of the substrate

When there is a large offset, it will affect the reshaping of the ball, and finally affect the electrical connection with the PCB board;

[0013] 2. During laser drilling, the laser will hit the ball, causing the ball to partially melt or completely melt, and there may be debris of plastic encapsulant wrapped into the solder ball, which poses a certain risk to the subsequent reliability;

[0014] 3. When the solder ball is remolded, due to the thinning of the solder ball and the offset of the laser, the forming height may be low or uneven, and it cannot be connected to the final PCB board;

[0015] 4. In the ball planting station, there may be problems such as large and small balls, bridging, etc., which need to be reworked and replanted, wasting time and efficiency

Images