Capacitor of semiconductor memory device that has composite Al2O3/HfO2 dielectric layer and method of manufacturing the same

摘要

A semiconductor memory device that includes a composite Al₂O₃/HfO₂ dielectric layer with a layer thickness ratio greater than or equal to 1, and a method of manufacturing the capacitor are provided. The capacitor includes a lower electrode, a composite dielectric layer including an Al₂O₃ dielectric layer and an HfO₂ dielectric layer sequentially formed on the lower electrode, the Al₂O₃ dielectric layer having a thickness greater than or equal to the HfO₂ dielectric layer, and an upper electrode formed on the composite dielectric layer. The Al₂O₃ dielectric layer has a thickness of 30-60 Å. The HfO₂ dielectric layer has a thickness of 40 Å or less.