| 摘要 |
PURPOSE:To enable to perform a dry etching on silicon or silicon compounds sticking on the surface of a semiconductor substrate while preventing a hindrance due to carbons to the dry etching by a method wherein a plasma etching or a sputter etching is performed on the surface thereof using fluorine-containing hydrocarbon having the carbons as etching gas. CONSTITUTION:When fluorine-containing hydrocarbon is used as etching gas, C ions and radicals generate, but H ions and radicals are also produced simultaneously and both are easily polymerized by the energy of plasma. For example, the two are polymerized into a compound in the form of -(CH2)- and the compound adheres on a material to be etched or the sidewall surface of a reaction vessel or is exhausted to the exterior. Fluorine-containing hydrocarbon having a small number of Cs is desirable as etching gas, because the less the number of Cs is, the less the hindrance due to the Cs to a dry etching is. In particular, fluorine- containing hydrocarbon having the number of Cs of less than two is desirable as etching gas. When gas containing at least one selected from among methyl fluoride fluoroform, trifluoroethylen, vinyl fluoride, ethyl fluoride or diofluoroethane is used as etching gas, a more favorable result is obtained. |
