Wafer level packaging costs reduced by up to 30% with new approach
1 min read
STATS ChipPAC has developed a new packaging approach in which wafers of varying diameters are reformatted into a uniform panel. The approach is said to deliver an 'unmatched' level of flexibility and cost savings for wafer level packaging (WLP).
"When 200mm wafers are reconstituted into 300mm or larger panel sizes, customers have greater potential for cost reduction than with conventional WLP manufacturing. As the panel size increases, the cost of producing wafer level packages drops significantly when compared to conventional WLP methods," said Dr Han Byung Joon, STATS ChipPAC's chief technology officer.
Using the conventional WLP approach, chips are fabricated, packaged and tested whilst in a wafer format in order to streamline the manufacturing process. Because WLP uses the same semiconductor equipment infrastructure as wafer fabrication, it becomes progressively more expensive with larger wafer diameters and finer silicon geometries. According to the company, costs associated with transitioning to larger wafer diameters have brought 'extreme pricing pressures' on WLP, particularly for wafer level chip scale packaging (WLCSP).
"Growing demand for WLCSP in a range of advanced mobile products – from low cost to high end smartphones and tablets – is driving capacity constraints in the industry, particularly with 200mm wafers," said Chong Khin Mien, STATS ChipPAC's senior vice president of product and technology marketing. "This is putting pressure on our customers to weigh the high cost of transitioning to more advanced silicon nodes against the need to achieve dramatic cost reductions for more competitive end products. This is an exciting time to drive a fundamental change in the manufacturing process for WLCSP."
STATS ChipPAC says its method, called FlexLine, allows multiple silicon wafer diameters to be processed in the same manufacturing line without changing equipment sets or bill of materials used in the packaging process. The result, says the company, is a simplification of the supply chain across multiple devices.
"STATS ChipPAC is driving a significant paradigm shift in wafer level packaging with FlexLine," Dr Han added. "We are the first company to introduce a WLP method that is completely independent of wafer sizes, including 450mm wafers, and delivers unprecedented flexibility in producing both fan out and fan in packages on the same manufacturing line.
"By normalising multiple wafer diameters to a uniform processing size through reconstitution, the original wafer diameter becomes irrelevant as this no longer dictates manufacturing capacity or limits process capabilities.
