We report a simple and low-cost fabrication of antireflection subwavelength grating (SWG) structures on GaAs using the lenslike shape transfer by a holographic lithography and a reflowed photoresist mask. The use of an additional thermal reflow process enhances the close packing of two-dimensional SWGs with a conical shape. The aspect ratio of conical SWG was also controlled easily by adjusting the rf power during the dry etch process. The fabricated SWGs exhibited low reflection properties over a wide spectral range, in agreement with the calculated values using by a rigorous coupled-wave analysis simulation.
© 2009 Optical Society of America
Diffraction and Gratings
Original Manuscript: January 5, 2009
Revised Manuscript: April 16, 2009
Manuscript Accepted: April 17, 2009
Published: May 28, 2009
Young Min Song, Si Young Bae, Jae Su Yu, and Yong Tak Lee, "Closely packed and aspect-ratio-controlled antireflection subwavelength gratings on GaAs using a lenslike shape transfer," Opt. Lett. 34, 1702-1704 (2009)