The search for low-/spl epsiv/ and ultra-low-/spl epsiv/ dielectrics: how far can you get with polymers? Part 2: materials, structures, properties

The need for continuing miniaturization of the structures on microchips has always resulted in new challenges concerning materials properties. A large variety of polymers have been proposed for this application, as organic materials are among those with the lowest dielectric constants known. The chemical structures and selected properties of these polymers are discussed in this review. Polymides; heteroaromatic polymers; polyaryl ethers; fluoropolymers, polyarylenes, and other hydrocarbon polymers without any polar groups; films deposited from the gas phase by chemical vapor deposition (CVD); plasma-enhanced CVD (PECVD); and other techniques are included. Based on the properties described and the requirements for application as intermetal dielectric (IMD) material, conclusions regarding the possibilities for further developments are draw. This article focuses on the structure, synthesis, and properties of the polymers studied as ILD/IMD materials.