| Abstract [eng] |
Laser-induced Damage in Semiconductor and Dielectric Material Wafers The light emitting diode (LED) market is growing rapidly at the moment. LED‘s are dominating in many areas of lighting and currently are quickly spreading into the common household and industrial lighting market, where conventional halogen, CFL and incandescent lamps are commonly used. The attractive properties of LED’s are as follows: high energy efficiency, outstanding device lifespan, mechanical durability, small size, wide selection of wavelength and other. All the properties are the major reason why the LED market is spreading and therefore the need to create more efficient LED production and treatment techniques is also increasing. In this study the process of laser damage formation, LED wafer dicing technologies are discussed. Also, LED quality control and efficiency enhancement methods are discussed. During this study experiments of laser induced damage threshold (LIDT) in semiconductor and dielectric media measurement, enhancement of light output power through the dicing profile by periodic laser induced damage structures within material, absorption of laser radiation within material while using conventional dicing parameters of laser radiation and LED wafer dicing, have been carried out. The major goal of this work is to study the impact of various processing parameters and methods on dicing efficiency and LED quality. During this study, 1, 2, 4 and 8 pulse LIDT has been measured while using 0,3 – 10 ps laser radiation. Also, it was observed that light out power through dicing profile was enhanced when laser diode was used as a sample illumination source. A laser radiation absorption efficiency dependence on laser focal depth within the sample has also been measured. Lastly, dicing of LED wafers has been performed and an increase of average LED light output power by 0.3% has been observed. |
