Development of the technology to control the spatial distribution of plasma using double ICP coil

Abstract

With the shrink of TSV diameter, smoothness of side wall and taper angle control become more and more important. We have developed scallop free etching by direct etching method. Direct etching method is continuous, not cyclical etching and deposition. Scallop does not occur in principle. Double ICP antenna newly developed has good controllability of side wall taper angle. IntroductionData traffic is increasing explosively with the spread of mobile devices such as mobile phone and tablet PC. Data server required high-speed processing and low power consumption. Devices used in these equipments are required high-speed processing, high density packaging and low power consumption. One of the most powerful way to achieve these requirements are 2.5D and 3D packaging using TSV. Via diameter becomes 10um or less, subsequent deposition process becomes difficult, because of high aspect ratio. Sidewall smoothness and controllability of taper angle have significant influence on the reliability and production costs. We have developed scallop-free etching using double ICP antenna. In this paper, we focused on the controllability of taper angle. Scallop-free and taper etching is expected to improve the reliability and production costs of liner/barrier seed layer deposition. Figure1. shows the etched profile by conventional method and our countermeasures.