Interconnect methodology employing a low dielectric constant etch stop layer

摘要

The capacitance between the gate of a transistor and local interconnect is reduced employing SiC as an etch stop layer. Embodiments include depositing a SiC etch stop layer having a thickness of about 500-1000 Å and a dielectric constant of less than about 3.2, thereby providing a composite dielectric constant between the gate and local interconnect of between about 3.7 to about 4.7. The SiC etch stop layer can be deposited by PECVD or HDP techniques.