Challenges for dielectric materials in future integrated circuit technologies

Dielectrics provide crucial functions in integrated circuits as gate dielectrics, transistor isolation structures, memory elements, interlevel dielectrics, and also provide charge storage in fast capacitors for power isolation. As the feature sizes of integrated circuits continues to decrease and speed increases, the performance requirements for these dielectrics increases significantly. Conventional materials such as thermal and CVD SiO2 are being replaced with new materials such as high k gate dielectrics, and carbon doped SiO2 for low k interlevel dielectrics. Even in package level power isolation capacitors, improvements in performance are becoming more difficult and new materials are needed. The challenges to dielectric materials will become even more severe as the industry approaches the l0 nm generation. In each of these applications, the requirements and integration issues are different, and this paper will highlight the long-term challenges for different applications of high k and low k materials. Nanotechnology has the potential to deliver new nano-structured materials to support these requirements, but significant challenges must be overcome before they can be useful.