High quality and high speed cutting of Al2O3 substrate with single mode fiber laser

Abstract

Alumina ceramic (Al2O3) is one of high performance thermal conducting substrate then widely used for several electric devices such as LED. One of key process, which will sometimes limits their productivity in LED production is singulation. As a conventional method, blade cutting is well known technique; however there are several disadvantages such as slow speed of 10mm/s and wear of blade due to physical contact. To solve this problem, laser cutting is one of ideal technique; however alumina ceramics have higher reflection for conventional lasers for material process.Recent progress of single mode fiber lasers enables remarkably high brightness at focal point. The power density reaches higher than 107 W/cm2, this power level make us possible to initiate cutting of alumina substrates both at high speed and high quality even though they have a poor absorbance at λ = 1084 nm, which is the wavelength of our fiber lasers. We have developed 500W single mode fiber laser and demonstrated alumina ceramics substrates singulation at more than ten times faster than the speed of the mechanical cutting. Excellent cutting quality was demonstrated at a single sweep process. A pretty smooth cutting surface and dross-free cutting does not require any additional finishing work.Alumina ceramic (Al2O3) is one of high performance thermal conducting substrate then widely used for several electric devices such as LED. One of key process, which will sometimes limits their productivity in LED production is singulation. As a conventional method, blade cutting is well known technique; however there are several disadvantages such as slow speed of 10mm/s and wear of blade due to physical contact. To solve this problem, laser cutting is one of ideal technique; however alumina ceramics have higher reflection for conventional lasers for material process.Recent progress of single mode fiber lasers enables remarkably high brightness at focal point. The power density reaches higher than 107 W/cm2, this power level make us possible to initiate cutting of alumina substrates both at high speed and high quality even though they have a poor absorbance at λ = 1084 nm, which is the wavelength of our fiber lasers. We have developed 500W single mode fiber laser and demonstrated alumina ceramics substrat...