Metal–oxide–semiconductor gate oxide reliability and the role of fluorine

As the metal–oxide–semiconductor (MOS) device down-scaling trend continues, the integrity and reliability of thin gate insulators have become a major concern for the development of current and future generations of integrated circuits. In this paper, some of the reliability issues concerning thin gate SiO2 and SiO2/Si interface will be briefly reviewed. Among the various methods being developed to improve the thin gate oxide reliability, a relatively simple approach involving the incorporation of fluorine will be covered in some detail. Several variations of introducing fluorine will be described, and their resulting effects on the MOS gate oxide reliability will be presented. The role of fluorine will be discussed.