Title :
High efficient light-emitting diodes with antireflection subwavelength gratings
Author :
Kanamori, Y. ; Ishimori, M. ; Hane, K.
Author_Institution :
Dept. of Mechatronics & Precision Eng., Tohoku Univ., Sendai, Japan
Abstract :
A two-dimensional subwavelength grating (SWG) has been fabricated on a GaAlAs light-emitting diode (LED). The SWG is patterned by electron beam lithography and etched by fast atom beam with Cl/sub 2/ and SF/sub 6/ gases. The fabricated grating has 200 nm period and the tapered grating shape with aspect ratio of 1.38 to prevent reflection in the spectral region including 850 nm light emission. The emission is increased by 21.6% at the normal emission angle. The total emittance is increased by 60% with the SWG in comparison with that of the flat surface.
Keywords :
III-V semiconductors; aluminium compounds; diffraction gratings; electron beam lithography; gallium arsenide; light emitting diodes; optical fabrication; sputter etching; 200 nm; 2D subwavelength grating; 850 nm; Cl/sub 2/; Cl/sub 2/ gases; GaAlAs; GaAlAs LED; GaAlAs light-emitting diode; SF/sub 6/; SF/sub 6/ gases; antireflection subwavelength gratings; aspect ratio; electron beam lithography; etched; fast atom beam; flat surface; highly efficient light-emitting diodes; light emission; normal emission angle; spectral region; tapered grating shape; total emittance; two-dimensional subwavelength grating; Atomic beams; Electron beams; Etching; Gases; Gratings; Light emitting diodes; Lithography; Optical reflection; Reluctance generators; Shape;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2002.1021970
