Laser machining with QCW fiber lasers

Abstract

Quasi continuous wave (QCW) fiber lasers operating in the near IR at 1070 nm have unique properties such high pulse energy with high peak power and very good beam quality. Consequently extreme high power densities are possible allowing for adequate coupling and high quality machining of materials that are typically transparent at these wavelengths. QCW lasers can operate with variable pulse length in pulsed mode at high repetition rate as well as in CW mode at high average power which translates into high throughput machining. Single mode and multimode fiber lasers can be used to match processing needs.In this paper we will present results covering laser processing with QCW fiber lasers of materials that are typically difficult to machine at near IR wavelengths, namely ‘white ceramics’ and sapphire.Results are shown for alumina, aluminum nitride and zirconia toughened alumina (ZTA). These are ceramics used in industries such as LED packaging as well as RF and microwave packaging. High speed drilling up to 3000 holes/sec is shown with hole diameters ranging from 100 to 15 microns, in material thicknesses ranging from 635 to 100 microns. Examples of high speed cutting and scribing are also presented.Results are shown for high quality cutting of sapphire up to 3 mm thick. Sapphire has received increased attention in the consumer electronics industry due to its increased use in applications ranging from mobile phone and tablet displays, to their lens cover, in addition to more common applications such as windows for the semiconductor and defense industry.Quasi continuous wave (QCW) fiber lasers operating in the near IR at 1070 nm have unique properties such high pulse energy with high peak power and very good beam quality. Consequently extreme high power densities are possible allowing for adequate coupling and high quality machining of materials that are typically transparent at these wavelengths. QCW lasers can operate with variable pulse length in pulsed mode at high repetition rate as well as in CW mode at high average power which translates into high throughput machining. Single mode and multimode fiber lasers can be used to match processing needs.In this paper we will present results covering laser processing with QCW fiber lasers of materials that are typically difficult to machine at near IR wavelengths, namely ‘white ceramics’ and sapphire.Results are shown for alumina, aluminum nitride and zirconia toughened alumina (ZTA). These are ceramics used in industries such as LED packaging as well as RF and microwave packaging. High speed drilling up to...