According to Maxime Darnon, a researcher at the French National Center for Scientific Research, in order to continue increasing the speed of integrated circuits, interconnect insulators will require an upgrade to porous, low-dielectric constant materials. Darnon and colleagues discuss the details in the Journal of Applied Physics, which is published by the American Institute of Physics (AIP).
"The integration of a replacement, porous SiCOH (pSiCOH), however, poses serious problems such as an unacceptable 'roughening' that occurs during plasma processing," explains Darnon. "This is considered a 'showstopper' to faster integrated circuits at the moment, so a fundamental understanding of the roughening mechanisms that occur during the etch process of integrated circuit manufacturing is highly desirable to material designers and etch-process engineers.
Darnon's research team proposes a mechanism for the roughening of pSiCOH materials etched in a fluorocarbon-based plasma. They've shown that the problematic roughness results from a cracking of the denser top surface under ion bombardment, and that this roughness propagates through a slower etching of the dense top surface than the modified porous material beneath it. Perhaps more importantly, the team recommends ways to minimize this phenomenon so that the "showstopper" will only be a speedbump on the road to faster integrated circuits.
The Journal of Applied Physics is the American Institute of Physics' (AIP) archival journal for significant new results in applied physics; content is published online daily, collected into two online and printed issues per month (24 issues per year). The journal publishes articles that emphasize understanding of the physics underlying modern technology, but distinguished from technology on the one side and pure physics on the other. See: http://jap.aip.org/
The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators and is one of the world's largest publishers of scientific information in the physical sciences. Offering partnership solutions for scientific societies and for similar organizations in science and engineering, AIP is a leader in the field of electronic publishing of scholarly journals. AIP publishes 12 journals (some of which are the most highly cited in their respective fields), two magazines, including its flagship publication Physics Today; and the AIP Conference Proceedings series. Its online publishing platform Scitation hosts nearly two million articles from more than 185 scholarly journals and other publications of 28 learned society publishers.
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The article, "Roughening of Porous SiCOH Materials in Fluorocarbon Plasmas" by Maxime Darnon et al will appear in the Journal of Applied Physics. See: http://jap.aip.org/