Low temperature oxidation and selective etching of chemical vapor deposition a-SiC:H films

Chemical vapor deposition silicon carbide films are considered as a perspective hard mask and stop layer in advanced dry etch technology because of the high chemical and plasma stability. However the a-SiC:H film should be etched away after technological use. In this case the high chemical stability of the a-SiC:If films troubles the solution of this problem. A new approach for the selective removal of the a-SiC:II films is discussed. The basic idea is low-temperature oxidation of the a-SiC:H film and selective removal of the reaction products by wet and/or dry etching. Fourier transform infrared, x-ray photoelectron spectroscopy, and ellipsometry were used for the characterization of the a-SiC:H oxidation and etching of the reaction product. As an example of the practical application, the a-SiC:H films were tested as a dry contact etch stop layer in a 0.18 mu m complimentary metal-oxide-semiconductor technology. Results of the electrical evaluation of test structures prepared by this technology art: discussed. These results show significant advantage of the new technology compared with the traditional one. (C) 2000 American Vacuum Society. [S0734-211X(00)04303-1].