Abstract
The effect of annealing temperature and time on the resulting resistivity of CoSi2 contacts with P-doped poly-Si was investigated using a single wafer furnace-based (hot wall) rapid thermal annealing (RTA) system. To achieve low resistivity contacts, CoSi2 formation process optimization was done by detailed design of experiment (DOE). Sheet resistance (Rs) response surface plots as a function of annealing temperature and time for 1st step and 2nd step RTA processes showed a very wide process window. The hot wall RTA resulted in significantly (>20%) lower Rs, over a very wide process window, compared to the equivalent RTA process using conventional tungsten halogen lamp-based (cold wall) RTA systems. Dopant (P) depth profiling results by secondary ion mass spectroscopy (SIMS) revealed that the P atoms in the CoSi2 film and at the CoSi2/P-doped poly-Si interface, redistribute very differently under different RTA conditions. The CoSi2 formation process was optimized utilizing characteristics of P pile-up near the CoSi2/P-doped poly-Si interface to suppress P depletion from the P-doped poly-Si layer for contact resistance minimization.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.