The fastest adoption of Fan-Out technology is now in 5G, automotive and healthcare. Traditional applications such as audio codecs, PMICs, micro-controller units (MCU) and radio frequency (RF) continue to use Fan-Out Wafer Level Packaging as an alternative to Wafer Level Chip Scale packaging (WLCSP) due to its 5 -sided or 6-sided die protection. As Fan Out packaging becomes mainstream and to get broader adoption of Fan-Out, the need for driving down the cost continues to be at the forefront of Fan-Out suppliers. Traditional 300mm carrier wafer for Fan-Out is currently the mainstream format used for PMICs, RF and other single die applications. As volume of these devices continue to ramp up, the 300mm medium used for Fan-Out processing continues to stay the same. The need for migrating to panel sizes larger than 300mm becomes a necessity to lower down costs and handle higher volumes. Not all products would benefit from migrating from circular 300mm carriers to large panel. If the total area of the panel is not fully utilized, it translates into wasted materials and loss. Currently, there is lack of panel-size standard in the industry. There are various panel sizes such as 300mm x 300mm (square), 457mm x 610mm, 510mm x 515mm, 600mmx 600mm, to name a few. The size of the panels chosen is dependent on utilizing existing equipment or processing capability that would utilize minimal capital expenditure. In 2011, Deca Technologies first established the 600mm panel standard. SEMI’s Fan -Out PLP Panel Task force had formulated a ballot process and 2 panel options had been narrowed down to 510mm x 515mm and 600mm x 600mm (Fan-Out). The 600mm x 600mm format would enable the panel to be singulated into 4x 300mm or 9x200mm square segments to enable utilizing existing probe test equipment in the industry. Coupling the 6-sided die protection process (M-Series) with 600mm x 600mm panel level processing paves the way for innovative methods for Fan-Out processing. New photolithography processing utilizing Adaptive Patterning to auto scale for die shift mitigation, is heavily dependent on segmentation of the panel. In this instance, the 600mm panel is either segmented into 4X 300mm, 9 x 200mm or 1x600mm for Photolithography steps. Depending on the number of fiducials used during the photolithography steps, capital expenditure and exposure accuracy would be highly dependent on the segmentation chosen. In addition, new metrology tools, panel warpage management will need to be considered for quality assurance. This paper will present the background of utilizing 600mm x 600mm panel size, the processing method for 6-sided die protection (M-Series) of a single die, large panel processing considerations, panel level inspection considerations post mold cure, reliability considerations and future of 600mm x 600mm panel level processing for 6-sided die protection.
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