Electron Cyclotron Resonance (ECR) Sputtered Antireflection Coatings on Laser Facets for Optical Memory Applications

Abstract

Antireflection (AR) layer coated semiconductor laser diodes may have many applications, particularly as external cavity diodes for optical memory heads. The electron cyclotron resonance (ECR) sputtering system was used for preparing AR coatings which consist of both SiO2 and Si3N4 phases. The refractive index and the thickness of the AR coatings were adjusted by controlling numerous deposition parameters, including the relative flow ratio of O2 and N2 gas flow, the total gas flow rate, the RF and ECR power, and the deposition time. AR coated AlGaAs laser diodes do not show a sharp threshold in the light output-current characteristic curve and have good potential for application in the lensless optical floppy systems.

Nanofocusing probe optimization with anti-reflection coatings for a high-density optical memory

“…Such an ARC should be used as a protective layer [17,19]. Silicon nitride (Si 3 N 4 ) is known as a hard protective film for opto-electronics [23]. The geometrical thickness d c of the ARC film is determined from the optical pass difference δ between the reflected rays or waves on the air/ARC and coating/GaP boundaries using the interference condition [25]…”

“…A parametrical approach for computer generation of the MLA surfaces and an algorithm for quantitative comparison of the etalon curves with the measured profiles of the real optical structures are developed in [22]. Good anti-reflection coatings (ARCs) of sufficiently low reflectivity were prepared by controlling the deposition variables in the electron cyclotron resonance (ECR) sputtering system [23]. These ARC results have been used for optical memory applications.…”