Novel packaging structures, encapsulation process and materials for matrix array over-molded flip chip CSP

New technologies of structure, materials and encapsulating process for over-coated flip-chip chip scale package (OFCSP) have been developed in this study. A MAP (matrix array package) type flip chip package with over-coating is developed by simultaneous encapsulating process which has the same universal production system as mini-BGA and doesn't need to change molding facility due to die shrink or product changed. A new 4/spl times/4 chips area array flip chip test vehicle was designed for this study. The new technology shows many advantages such as: high. electric performance, low cost, good reliability property, high throughput, thinner package, and void free during encapsulating process. Not only remarkable down-sizing, but also a new developed package are shown in this study together with miraculous property of soldering resistance. The OFCSP is developed by vacuum molding under simultaneous encapsulating process without void remain, and fine filler molding compounds for underfilling penetration well. It can pass perfectly level 1 JEDEC standard at 230/spl deg/C reflowing and level 2 JEDEC standard at 260/spl deg/C reflowing. It can also pass the reliability testing items including USPCT, TCT and HST after pre-condition of JEDEC level 3. Since the perfect property of soldering resistance is deeply related with package structure, encapsulant properties and process, the technology developed in this study can be applied for more advanced package such as paper-thin package, FC/WB embedded stacked package etc.