A camera module packaging method and process

Background technique:
The camera is a widely used electronic device component, commonly used in smartphones, driving recorders, monitors, etc. The camera at least includes photosensitive elements, circuit boards, imaging components, and can also include filter components, optical focusing components, etc. When all components are packaged together, it becomes a camera component that can be directly applied to electronic devices. Commonly used packaging methods include COB (Chip on Board), that is, the photosensitive chip is bonded to the substrate through gold wire, and then the lens and bracket (or motor) are bonded to the substrate; CSP (Chip Scale Package), that is, the photosensitive chip is bonded to the substrate through SMT is welded to the substrate, and then the lens and bracket (or motor) are bonded to the substrate; MOB (Mold on Board), that is, the photosensitive chip is bonded to the substrate through gold wires, and then the capacitors and resistors are packaged through injection molding, and then Bond the lens and bracket (or motor) to the capacitor and resistor package; MOC (Mold on Chip), that is, the photosensitive chip is bonded to the substrate through gold wire, and then the non-photosensitive area of the chip is packaged with the capacitor and resistor through injection molding Get up, and then glue the lens and bracket (or motor) to the capacitor and resistor package. At present, most of the most common packaging processes are based on MOC packaging processes, but during specific implementation, we must also consider a very likely thing to happen: plastic overflow; as shown in Figure 5, the existing MOC process has a negative impact on mold accuracy and injection molding. The precision requirements are very high. If there is a deviation in the mold or during injection molding, the plastic may overflow into the photosensitive area of the chip, causing the photosensitive chip to be damaged. If the mold tolerance is not well controlled or the PCB is deformed, glue overflow can easily occur. Once the injection molded plastic overflows into the photosensitive area of the chip, it will cause defects such as chip photosensitive area failure, and because the chip photosensitive area is very fragile, such defects cannot be repaired.

Technical characteristics:
1. A camera module assembly method, characterized by: including the following steps:
Step 1: Design an optical filter (6) of appropriate size according to the size of the chip photosensitive area (2) of the photosensitive chip (5) and the distance between the chip photosensitive area (2) and the pad. The size of (6) must not be smaller than the size of the photosensitive area (2) of the chip, and it must not cover the photosensitive chip pad (4);
Step 2: Attach the filter (6) to the photosensitive area (2) of the chip, covering the photosensitive area (2) of the chip but not covering the photosensitive chip pad (4);
Step 3: Bind the photosensitive chip (5) to the circuit board (1);
Step 4: Place it in a mold for molding, use a plastic molding method to inject injection molding plastic (7) onto the circuit board (1) to form a plastic package that covers the photosensitive chip ( 5) non-photosensitive area;
Step 5: Install other components on the basis of the plastic package.
2. The camera module assembly method according to claim 1, characterized in that: the step three can be placed in front of the step one to become a new step one, and the step one becomes a new step two, Said step two becomes the new step three.
3. The camera module assembly method according to claim 1, characterized in that: the filter (6) is an infrared cut-off filter. Technical summary
The present invention proposes a camera module assembly method. Based on the existing MOC technology, before the overall injection molding step, the filter is attached to the photosensitive area, and then placed in the mold for molding. The plastic molding method is used to inject injection molding plastic onto the circuit board to form a plastic package. The plastic package covers the non-photosensitive area of the photosensitive chip. The invention can prevent plastic from overflowing into the photosensitive area of the chip.