ABLATING SIC WAFER CONFIGURATIONS AND MANUFACTURING LIGHT EMITTING DIODE (LED) DEVICES

摘要

The invention proposes a manufacturing method for enhancement of the luminosity of SiC-based LED devices using double exposure of the light-emitting surface of a LED device or LED component or SiC wafer to linearly polarized radiation of a femtosecond laser beam of a proper fluence. The first exposure results in the formation of a pattern of parallel periodic grooves onto SiC surface. Then the LED device, or LED component, or SiC wafer is rotated by 90 degrees and subsequently irradiated for a second time. The double exposure results in the formation of an array of regular depressions and nanogrooves onto SiC surface. These depressions act as an anti- reflecting coating due to smooth variation of the refractive index from its value in the crystal to air and lead to the increase of internal quantum efficiency of LED. The manufacturing method can be performed during the LED device fabrication or as a pre- or post- fabrication step. The manufacturing process can be performed in air or after immersion of a LED device, or LED component, or SiC wafer in liquid.