Ball Grid Array (BGA) is a PCB chip assembly in which the chip is fixed on a substrate of metal balls.
The main purpose of BGA is to provide a secure attachment and prevent micro-movements and detachment of the chip from the board. The BGA mounting process includes:
- Application of solder balls. Metal balls with a diameter of 0.15 to 1 mm are applied to the bottom surface of the chip in contact with the board. The standard size of the balls is 0.4 to 0.5 mm. - Heating. The chip is evenly heated with a thermofan or soldering station to melt the solder balls. The temperature and heating time are selected depending on the chip type and solder characteristics. - Surface tension. As the solder melts, the chip body is centered equidistant from the board. The surface tension of the molten solder promotes the correct positioning of the chip according to the contact pattern on the board and chip.
BGA technology offers a number of advantages over other mounting methods:
- High density. Solder balls reduce chip size and weight by placing more pins in a smaller area. - Reliability. The lack of through-holes eliminates potential points of failure, providing better protection against mechanical stress and vibration. - Easy soldering. BGA assembly can be automated with specialized equipment, reducing the risk of manual soldering errors.