Film properties and integration performance of carbon doped oxides

Abstract

Summary form only given. The semiconductor industry has witnessed a successful introduction of copper based interconnects and low permittivity insulators with 130nm node devices. The advent of 90nm node devices has led to the introduction of first generation of carbon doped dielectric films. Further scaling will require materials with lower permittivity and this has accelerated the development of a second generation of carbon doped oxides with imbedded porosity. While the addition of carbon to a silicon based dielectric lowers the permittivity of the insulator, carbon doping may also lead to degradation in the surface properties of such films. Frequently, carbon enrichment at surfaces is known to cause issues with the wetting characteristics of the surface. In addition, the mechanical strength of interfaces formed with carbon enriched surfaces may be poor compared to congruent surfaces. The high number of chemically and morphologically different materials in the integrated interconnects structure increase the possibility of mechanical structural failure. A detailed understanding of the basic material properties and the behavior of the carbon doped materials during subsequent processing is therefore of prime importance. This paper will present an overview of process and film property characterization of different generations of carbon doped oxides. Integration properties of these films and correlation to processing parameters and physical properties of the materials will be discussed. Novel processing techniques are discussed that enable the implementation of advanced low dielectric constant materials without sacrificing the high volume manufacturability of such films.