The purpose of this study was to assess the clinical performance of composite restorations placed with different adhesive systems in primary teeth. In 32 patients, 128 composite restorations were placed using a split-mouth design as follows (4 groups/patient): three-step etch-and-rinse (Group 1), two-step etch-and-rinse (Group 2), two-step self-etch (Group 3), and one-step self-etch (Group 4). ...

Using a combination of low-pressure oxygen and high temperatures, isotropic and anisotropic silicon (Si) etch rates can be controlled up to ten micron per minute. By varying the process conditions, we show that the vertical-to-lateral etch rate ratio can be controlled from 1:1 isotropic etch to 1.8:1 anisotropic. This simple Si etching technique combines the main respective advantages of both w...

The purpose of this study was to evaluate the five-year clinical performance of a two-step self-etch adhesive in non-carious cervical sclerotic lesions with or without selective acid-etching of enamel margins. A total of 104 cervical restorations in 22 patients (46-64 years) were bonded following either self-etch approach (AdheSE non-etch) or a similar application, including selective acid-etch...

A simplified process to fabricate high aspect ratio nanostructures in silicon combining electron beam lithography and deep reactive ion etching (DRIE) is presented. A stable process (HARSiN) has been developed without the need for complicated resist/hard mask processing or complex dry etch technologies. This is achieved using commercially available ZEP520A resist from Nippon Zeon Co., Ltd which...

Dry etching is an important process for micro- and nanofabrication. Sputtering effects can arise in two contexts within a dry-etch process. Incoming ions cause removal of volatile products that arise from the interaction between the dry-etch plasma and the surface to be etched. Also, the momentum transfer of an incoming ion can cause direct removal of the material to be etched, which is undesir...

The aim of the study was to evaluate effect self-etching silane primer on long-term bonding strength feldspathic ceramic. Ceramic blocks (IPS Empress CAD, Ivoclar Vivadent) were cut with a low-speed diamond disk (Isomet 1000, Buehler) into 40 12x7x6mm, under water cooling, and randomly divided two groups (n=20), according surface conditioning: hydrofluoric acid (HF) (Condac, FGM) or (MEP) (Mono...

In the fabrication of microstructures in SiO2 , etch selectivity of SiO2 to masking, etch stop, and underlayer materials need to be maintained at corners and inclined surfaces. The angular dependence of the SiO2-to-Si3N4 etch selectivity mechanism in a high density fluorocarbon plasma has been studied using V-groove structures. The SiO2 etch rate on 54.7° inclined surfaces is lower than on flat...

Reactive ion etching is a widely-used technique for fabricating via holes in polymer-metal multilayer interconnect structures. Reactive ion etching of thin film polymers was studied using Benzocyclobutene polymer and photoresist etch mask, in O2 and SF6 plasma. A design of experiments (DOE) was carried out with rf power, pressure, and SF6 concentration as the design variables, with a constant t...

We have investigated the optical properties of surface-micromachined polycrystalline silicon reflectors within the visible spectral range at five different wavelengths. The measurement results of the reflectivity of various microreflectors at four different incident angles (20 , 30 , 45 , and 60 ) are presented. Optical properties of microreflectors realized using the multiuser MEMS process (MU...

It is well established that the bulk etch rates for solid state nuclear track detectors are a ected by the concentration and the temperature of the etchant. Recently, we found that the bulk etch rate for the LR 115 detector to be a ected by stirring during etching. In the present work, the e ects of stirring on the bulk etch rate of the CR-39 detector is investigated. One set of sample was etch...