The influence of the environmental conditions on conductive atomic force microscopy (CAFM) characterization of advanced MOS gate dielectrics was investigated. The effect of the environment on AFM measurements was built by placing a commercial CAFM into a chamber, which can be evacuated up to a pressure of 7 × 10-6 Torr. The CAFM was operated in contact mode using Pt/Cr coated Si tips. Topography maps of a larger area that includes the previously scanned region was also measured for high-k dielectric samples after a gate injection scan of 7 V in vacuum and in ambient conditions. the topographical profiles showed changes of 1.1 nm in vacuum and 4.3 nm in air ambient conditions. A vacuum CAFM was developed to perform vacuum electrical tests at nanometer scale. IV characteristics measured in vacuum environment show lower voltage and larger currents compared to in-air results, pointing out better conductivity measurements when working in vacuum.
|Journal||Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures|
|Publication status||Published - 25 Aug 2008|