Zurich, Switzerland -- DEK has developed a high-throughput backside wafer coating process, which is hosted on a mass imaging platform capable of exceeding the +/- 12.5 um total thickness variation (TTV) required by most wafer processing specialists. The process is compatible with underfill or adhesive-type coatings which are normally applied at a nominal 50 m thickness to the backside of semiconductor wafers prior to singulation.

“For any backside wafer coating process, TTV is the critical success factor,” said Clive Ashmore, global applied process engineering group manager. “With this latest application advancement, we are helping semiconductor packaging manufacturers increase throughput and reduce the cost per package by using high accuracy mass imaging.”

According to the company, the use of an optional wafer handler, flexible printing platform and reflow oven achieves more flexibility than dedicated backside coating machines. The system can be re-deployed for other processing requirements.

The backside wafer coating process is compatible with the company’s metal stencil and emulsion screen technologies. Metal stencils enable materials with larger filler particles, such as encapsulation materials, to be applied with a totally smooth surface finish. Mesh stencils allow other materials such as thermoplastic adhesives to be deposited accurately and at high speed. In each case, the capabilities of the machine and stencil technology are key to achieving control over the print thickness and ensuring uniformity at high volumes.

DEK, dek.com