A novel solution to improve static and dynamic retention characteristics by enhancing hydrogen passivation with in situ LD-TEOS/TEOS dual layer

Abstract

We proposed a novel solution to improve both static and dynamic retention characteristics by additional etching of the thickness of SIBN, stopper when oxide etch, with in-situ dual low deposition-tetraethyl orthosilicate (LD-TEOS)/TEOS Dual layer. As DRAM Cells shrink, it is difficult to obtain reliable retention properties, so it becomes more significant to reduce the Number of Interface Trap (Nit) by hydrogen passivation. In this work, interface trap decreased by reducing the thickness of SIBN, which has low hydrogen diffusion coefficients, improve the static and dynamic retention characteristics simultaneously through enhancing hydrogen passivation with In-situ LD-TEOS Dual (ILD) layer compensating for Metal contact to Other Bit line pad distance (MOB) margin risk.