Semiconductor Measurement Technology:Angular Sensitivity of Controlled Implanted Doping Profiles.

摘要

Ion implantation can be used to produce accurately controlled doping profiles for silicon devices and integrated circuits. The work reported here determines the angle at which the ion beam must strike the substrate in order to maintain control over the channeled and random equivalent depth distributions of carriers as measured by 1-MHz differential capacitance-voltage (C-V) profiling. A method to calculate the classical critical angle for channeling is presented. Data are presented that characterize the variation in the depth distribution of carriers with substrate orientation,incident ion species,and incident ion energy,for a range of critical angles. This study establishes the degree of control of the angle between the ion beam and the crystallographic orientation needed to produce the limiting cases of either optimal channeling or maximum randomization of ion trajectory in the substrate.