| 摘要 |
<p>The present invention relates to the etching of a gate film, a tungsten film, a silicon film, etc. In the present invention, use is made of an etching gas comprising a mixture composed of a reductive fluoride gas, a hydrocarbon gas and a halogen gas having a larger atomic diameter than a material to be etched, or a mixture composed of a reductive fluoride gas and a Cl-containing hydrocarbon gas, and the process comprises the step of conducting anisotropic etching of a material to be etched with an etching gas (a reductive fluoride gas), the step of forming a protective film by a depositing gas (a hydrocarbon bas), and the step of removing excess deposits formed as the protective film by means of a gas reactive with the protective film (a halogen gas or a Cl-containing hydrocarbon gas), wherein anisotropic etching is conducted by forming a protective film on a side wall while removing excess deposits formed as the protective film, thus enabling the anisotropic etching to be conducted with good accuracy. <IMAGE></p> |
