| 摘要 |
<p>PURPOSE:To achieve the high selectivity of a resist by using an etching gas containing a halogen compound which is provided with the following inside molecules: a functional group of at least one out of a thionyl group and a sulfuryl group; and halogen atoms. CONSTITUTION:When an etching operation is performed by using a mixed gas of SOCl2 and Cl2, an Al-based multilayer film 7 is removed in the form of AlClx, TiClx or the like. At the same time, CClx is produced as originated from the decomposition product of a resist mask 8; in addition, a thionyl group is taken into its structure, and a strong carbon-based polymer is produced. The carbon-based polymer is deposited on the sidewall part of a pattern, and forms a sidewall protective film 9. It displays a highly etching-resistant property even in small quantities, and contributes to an anisotropic working operation As a result, an Al-based interconnection pattern 7a which is provided with a good anisotropic shape is formed. Thereby, it is possible to achieve high anisotropy and high selectivity of the title formation method.</p> |
