Dry etching of Al-rich AlGaAs with silicon nitride masks for photonic crystal fabrication

Abstract

We investigate inductively coupled plasma (ICP) deep dry etching of Al0.8Ga0.2As for photonic crystal (PC) fabrication using a Cl2/BCl3/CH4 gas mixture. On the basis of our previous report [Y. Kitabayashi et al., Jpn. J. Appl. Phys. 52, 04CG07 (2013)], we obtained a PC structure having air holes deeper than 1.5 µm and a diameter of 120 nm by adjusting the gas flow rate and increasing the process pressure. In this study, silicon nitride (SiNx) and SiO2 were both used as the mask layer. Furthermore, samples with SiNx and SiO2 masks for ICP deep dry etching were also fabricated and compared. The vertical profile of the PC structure with the SiNx mask layer displayed a rounded shape that was caused by the charge up in the mask layer. Then, a thinner mask layer was used to ease the effects of mask retardation and charge up. As a result, a PC structure with a SiNx mask layer having air holes deeper than 1.7 µm and a diameter of 190 nm was successfully fabricated.

1.3 µm lasing of circular defect cavity photonic crystal laser with an AlO<i>_x</i> cladding layer

“…Thirdly, the sample was etched by inductively coupled plasma etching process [12] to form the air holes which penetrate the core layer. Then, the sample was emerged in the remover to take away the resist.…”

“…The second point is that it is possible to realize vertical current injection by using a special heterostructure which has been introduced in Refs. [5,12]. The vertical current injection design reduces the footprint of the PC laser to the area of the cavity, so that the bandwidth density will be much higher than the one using LEAP laser or 1D cavity.…”

Investigation of the disorder of Ga1–xAlxAs mixed crystals. Part I: Small concentrations

“…The electronic and optical properties of Ga 1– x Al x As mixed crystals in the form of bulk alloys , nanowires , or quantum dots are still under investigation because of the variety of optoelectronic applications of this zincblende crystal class. The phonons of these crystals have been studied by Raman and infrared spectroscopy and classified as two‐mode systems .…”

Computational Design of a Split Cavity with Localized Independent Electric Field Tunability

“…We first use COMSOL simulations to show that this cut cavity design permits the application of distinct electric fields to the two spatially separated qubits with negligible cross talk. We then use finite difference time domain simulations to adjust the cavity design to achieve a cavity Q of 20,000 while remaining within the parameter space that allows such a device to be fabricated using the existing methods. − We note that we chose a numerical optimization process that allowed us to rapidly determine the viability of this approach, and as a result, there is likely room for significant additional improvement with the application of more sophisticated inverse design, genetic algorithm, or machine learning approaches. − ,− …”