Plasma enhanced chemical vapor deposited SiCOH dielectrics: From low-k to extreme low-k interconnect materials

Plasma enhanced chemical vapor deposition technique was used to prepare carbon doped oxide dielectrics comprised of Si, C, O and H (SiCOH). Low-k films with a dielectric constant (k) of about 2.8 were deposited from tetramethylcyclotetrasiloxane (TMCTS). The entire range of SiCOH films demonstrated relatively low coefficients of thermal expansion of about 12×10-6 K and mechanical properties that make them suitable for integration as the interconnect dielectric in ultralarge scale integration (ULSI) devices.