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...

We demonstrate annealed low-temperature grown ~LTG! GaAs to be a highly effective etch-stop layer while photoetching n-type normal-growth-temperature GaAs. During this process, the etch rate is controlled by the transport of photogenerated carriers to the semiconductor/electrolyte interface. Because of the very short minority carrier lifetime in LTG-GaAs, only a very small portion of photogener...

A micromachined test structure was used to measure the etch rate of silicon in potassium hydroxide (KOH) as a function of surface orientation, which quantifies etchant anisotropy. By adding multidentate ligands, containing hydroxyl groups, to etchant solutions, the effects of these ligands on etch rate were determined. Bidentate ligands 1,2-ethanediol, 1,3-propanediol, and 1,4-butanediol each s...

OBJECTIVE The aim of the study was to evaluate the microtensile bond strength (µTBS) of Scotchbond Universal to dentin using the etch-and-rinse or the self-etch technique after 24 h and 6 months of storage. MATERIALS AND METHODS Flat dentin surfaces were obtained in 24 third molars. The teeth were divided into four groups: G1 - Scotchbond Universal applied in the etch-and-rinse mode; G2 - Sco...