Particle-free semiconductor dicing using the water jet guided laser technology

Abstract

Separation of semiconductors is a challenge for laser based cutting techniques since many years, because of the sensitive material. Until recently, the standard process for dicing semiconductor wafers was abrasive sawing that has been optimized for this application over more than 2 decades. However, the demands of new emerging types of semiconductor devices, like those based on thin wafers and on compound semiconductors, can no longer be fulfilled by abrasive sawing and new separation methods are investigated. The water jet guided laser showed some years ago to be a good alternative for dicing and free-shape cutting of thin semiconductors including GaAs, and is now qualified in terms of particle generation.Particle generation and redeposition is an important problem for all classical laser-cutting techniques. The water jet guided laser already features an inherent rinsing by the water jet and thus produces much smaller amount of particles than any other laser process. Recently, particle-free dicing of wafers could be achieved by covering the whole work piece with a well-controlled thin water film during the entire cutting process. This paper will compare the particle quantities after usage of different laser dicing processes. For the Laser Microjet® the benefits of a clean surface are discussed in more detail.Separation of semiconductors is a challenge for laser based cutting techniques since many years, because of the sensitive material. Until recently, the standard process for dicing semiconductor wafers was abrasive sawing that has been optimized for this application over more than 2 decades. However, the demands of new emerging types of semiconductor devices, like those based on thin wafers and on compound semiconductors, can no longer be fulfilled by abrasive sawing and new separation methods are investigated. The water jet guided laser showed some years ago to be a good alternative for dicing and free-shape cutting of thin semiconductors including GaAs, and is now qualified in terms of particle generation.Particle generation and redeposition is an important problem for all classical laser-cutting techniques. The water jet guided laser already features an inherent rinsing by the water jet and thus produces much smaller amount of particles than any other laser process. Recently, particle-free dicing of waf...