UV-blocking technology to reduce plasma-induced transistor damage in ferroelectric devices with low hydrogen resistance

This paper presents an ultraviolet (UV) light blocking technology in which a UV blocking layer is applied to the LSI device below the interconnection layer. Process-induced damage is dramatically reduced by this technology. This can be explained by the proposed process-induced damage model in which both the gate charging due to charged particles in the plasma and the electron excitation due to UV-photons from the plasma together cause the transistor degradation. This technology enables the fabrication of ULSI devices without final hydrogen annealing and is particularly useful for FRAMs which have low hydrogen resistance.