TLS-Dicing – The Key to higher Yield and Throughput for thin Wafers

摘要

Thermal Laser Separation (TLS)-Dicing is a fast, clean and cost effective alternative to known dicingrntechnologies. The process uses thermal induced mechanical forces to separate brittle materials such as Silicon,rnGaAs. Thermal stress is introduced in a well defined region via a laser beam. Cooling is applied via a Di-waterspray.rnThe induced forces separate brittle materials by cleaving. TLS is a true cleaving process which results inrnan edge with excellent quality, without chipping or micro cracks. This high edge quality results in a significantlyrnhigher mechanical breaking strength and an increased blocking voltage for vertical integrated devices. TLSrnDicing is a zero kerf process which has the potential to reduce street width and increases yield. The maximumrnTLS-dicing speed of 300 mm/s is much faster than any other dicing technology for thin wafers. This paper willrndiscuss the theory, benefits and limits of TLS. A comparison of TLS with other laser dicing technologies willrnalso be presented. To conclude, this paper will provide the latest results achieved by TLS and an overview of thernJENOPTIK TLS tool.. TLS is a interesting alternative for sawing and ablative laser dicing technologies as wellrnas an enabling technology for new products. TLS is especially well suited for RFID, dies for 3D-stacking,rnflexible products (chip cards), MEMS, optical devices and thin dies (e.g. power devices or solar wafers.)