The effects of plasma surface modification on the molding adhesion properties of Film-BGA package

The main purpose of this investigation is to study and calculate the adhesion strength more easily with quantitative rules in surface modification. The adhesion properties of film ball grid array (Film-BGA) substrate under various plasma treatments were also analyzed. Optimization of the plasma surface modification processes was achieved by varying parameters, such as radio frequency (RF) power, operating vacuum pressure, processing time, and flow rate of the chamber for the mixture of argon and oxygen gases. hesion abilities were analyzed from the adhesion work titration, the stud pull test, ultrasonic test (UT) measurements, pressurized-cook test (PCT) and X-ray photoelectron spectroscopy (XPS) analysis. The consistence of the adhesive work and the stud pull test represented the availability of using titration to quantitatively calculate the adhesion performance between the Film-BGA substrate and SUMITOMO EME-7372A molding compounds. The larger adhesive work value indicated the more adhesive strength. From the adhesion work titration, UT analysis and stud pull test results, using the recipe [300 W, 67 Pa, 3 min, 100 standard cubic centimeter per minute (sccm) Ar+50 sccm O2], the best adhesion strength was obtained. At the same time, the XPS results indicated the more the carbonyl (CO) bonds, the better the adhesion between the molding compound and the Film-BGA substrate.