Environmental, safety and health issues asociated with low dielectric constant films grown by chemical vapor deposition

摘要

Low dielectric constant (k) materials are desired for improved interconnect performance. These new interlayer dielectrics (ILDs) must satisfy an array of process integration issues, including Environmental, Safety, and Heath (ESH) considerations. From the ESH perspective, chemical vapor deposition (CVD) is desired over spin-on application because CVD avoids solvent usage. Also, the ESH impact will scale with the number of ILD layers. Thus, the technological goal of lower k, which reduces the number of ILD levels, is also favorable from an ESH perspective. ESH considerations were used to screen potential CVD feed gases prior to undertaking experiments. Fluorocarbon (CF_x) films were deposited from the most desirable gases. The films were found to have dielectric constants <2.4 and low dielectric loss tnagents (<0.01).