Suspended waveguides have been widely applied to silicon-on-insulator structures because they are easily fabricated with processing techniques similar to those of integrated circuit design. However, it is difficult to fabricate such structures in lithium niobate, which is also a very important material for optoelectronics. One main challenge is the difficulty of etching lithium niobate. In this...

The effects of HF/NH4F, wet chemical etching on the morphology of individual surface fractures (indentations, scratches) and of an ensemble of surface fractures (ground surfaces) on fused silica glass has been characterized. For the individual surface fractures, a series of static or dynamic (sliding) Vickers and Brinnell indenters were used to create radial, lateral, Hertzian cone and trailing...

We propose the metal-assisted chemical etching of Ge surfaces in water mediated by dissolved oxygen molecules (O2). First, we demonstrate that Ge surfaces around deposited metallic particles (Ag and Pt) are preferentially etched in water. When a Ge(100) surface is used, most etch pits are in the shape of inverted pyramids. The mechanism of this anisotropic etching is proposed to be the enhanced...

OBJECTIVES To evaluate the effect of different bonding strategies on the microtensile bond strength to deep and superficial permanent dentin. METHODS Forty-eight teeth were randomly flattened according to the dentin depth: superficial dentin (SD) and deep dentin (DD). Subsequently, three adhesive systems were applied (n=8): an etch-and-rinse (Adper Single Bond 2 - SB), a "mild" two-step self-...

Wafer and die level uniformity effects in Deep Reactive Ion Etching (DRIE) are quantitatively modeled and characterized. A two-level etching model has been developed to predict non-uniformities in high-speed rotating microstructures. The separation of wafer level and die level effects is achieved by sequentially etching wafers with uniformly distributed holes. The wafer level loadings range fro...

Abstract The aim of this article is to study the nature defects arising on surface silica glass during mechanical processing followed by chemical cleaning and etching. Such manifest themselves as a narrow Raman peak near 85 cm –1 . It shown that etching ground leads formation microcrystalline embedded at depth near‐surface layer. Defects kind create heterogeneities in structure atomic network i...

In this study we have investigated the effect of starting GaAs semi-insulating substrate surface (polished / unpolished), type of mask used (photoresist / Nickel) and RIE parameters (pressure and power) on the surface smoothness/morphology of the etched via-walls and resultant etch profiles with CCl2F2 / CCl4 gas chemistry. The ultimate aim of the study has been to develop a reliable via-hole g...