Interconnections in Multilayer PCBs Based on Microvias Metallized by Magnetron Sputtering Deposition
The high advanced miniaturization of electronic components determines designers and producers of PCBs (printed circuit boards) to search the new constructions and technologies of HDI (high density interconnect) PCBs manufacturing. The researches are concentrated on the problems of miniaturization of PCBs interconnections. Many possibilities in this area are created by using microvia technology. The microvias can be made by using several techniques of drilling, but the great problem in this aspect is connected with possibilities of proper and repeatable metallization of microvias. Wide practical techniques of metallization allow to properly metallize of blind microvias which aspect ratio (deep/diameter of microvia) is about 1 or less. In the paper we propose the use of the magnetron sputtering deposition of copper to metallize the high aspect ratio blind microvias. During tests the use of magnetron self-sustaining mode also was investigated. This special mode allow to deposit of thin and very clear (without labour gas particles) electro-conductive layers which can be grown in electroplating processes
Optical emission spectroscopy of self-sustained magnetron sputtering
Abstract The results of plasma investigation during very high power magnetron sputtering processes are presented. Magnetron sputtering during both standard and self-sustained modes was investigated. Owing to very effective target cooling and appropriate magnetic field distribution, the high target power density could be reached (up to ∼1000 W/cm 2 , ∼1.5 A/cm 2 ). A copper target 50 mm in diameter and 7 mm in thickness was used during the experiments. Two modes of magnetron sputtering, i.e. standard and self-sustained, were investigated. Optical emission spectra were measured. The emission intensity of the Cu species as a function of target power density during both magnetron sputtering modes was observed. The spectra were observed in the 200–800 nm wavelength range. When target current rose, the emission intensity of copper ion lines increased and neutrals ones decreased.
Kidney and urinary tract diseases in the newborn
Kidney and urinary tract diseases in the newborn / , Kidney and urinary tract diseases in the newborn / , کتابخانه دیجیتال جندی شاپور اهواز