User:Eric1014

AFOP is the short of Au(Gold) Finger OSP PAD which was invented by a Taiwan based IC substrate supplier - Unimicron Technology, and their Vice President - Shaw Wen Lao, when he was still a RD manager try to solve the interconnection problem for his customer to enhance the interconnection of solder ball with its mother ball to prevent the intermittence failure due to the " drop " accidentally of a mobile phone to the hard ground.

Due to the size limitation of a mobile phone, the electronics component inside it has a form factor consideration, in terms of a semiconductor device, the Chip Scale package ( CSP in short ) is their best solution to handle a high I/O in a small package body inside a mobile phone. The interconnection between CSP and to the mother board of a mobile phone usually use an array of solder balls attached to the circuit board of the mobile phone, after the reflow condition, solder balls form an Inermetallic compound ( IMC ) layer with the circuit board pads which forms the main strength of the interconnection of CSP to its ciucuit board.

Intensive studies to enhance the IMC strength has been done through out the industries, many possible solutions has been proposed