@article{oai:nagoya.repo.nii.ac.jp:00005491,
 author = {Fujita, Kazushi and Hori, Masaru and Goto, Toshio and Ito, Masafumi},
 issue = {6},
 journal = {Journal of Vacuum Science & Technology B},
 month = {Nov},
 note = {An environmentally benign etching process using a solid material evaporation technique has been investigated for preventing global warming. In this process, a polytetrafluoroethylene is evaporated by a CO_2 laser, resulting in production of fluorocarbon species working as the etching species. Therefore, this system employs no perfluorocompound feed gases, which cause global warming, and enables us to design a new plasma chemistry using the solid material. The system was successfully applied to a SiO_2 contact hole etching process employing a planar electron cyclotron resonance plasma. The etched profile was successfully controlled by varying the Ar dilution ratio and the process pressure. In a 0.6 μm contact hole and a 0.08 μm trench fabrication process, this novel process enables us to realize high etching performances, where the etching rate of SiO_2 , selectivities of SiO_2/resist, and SiO_2 /Si were 340 μm/min, 6.8 and 31, respectively, in optimal condition. To clarify the plasma chemistry using solid material evaporation, CF_x (x=1 – 3) radical densities and F atom density were measured by infrared diode laser absorption spectroscopy and actinometric optical emission spectroscopy, and fluorocarbon films deposited on SiO_2 were analyzed by x-ray photoelectron spectroscopy. On the basis of these results, the etching mechanism was discussed.},
 pages = {2192--2198},
 title = {Silicon oxide contact hole etching employing an environmentally benign process},
 volume = {20},
 year = {2002}
}