| 초록 |
In ArF lithography for sub-80nm memory devices, amorphous carbon layer(ACL) deposition becomes an evitable process, because thin ArF resist itself cannot provide suitable etch selectivity to sub-layers. However, one of the problems of the ACL hardmask is the presence of surface particles, which are more problems in mass production. Limited capacity and low process efficiency also make the ACL hardmask a dilemma, which cannot be ignored by device makers. Therefore, we have been using the spin-on multilayer hardmask including a resist as an imaging layer, a BARC as an intermediate layer, a Si-SOH as a spin-on hardmask layer containing silicon, and a C-SOH as a spin-on organic hardmask layer containing carbon. In this study, the SOH materials applicable to sub-70nm memory devices are described in terms of photo property, etch property, and process compatibility. |
