With the technology scaling and process improvement, do you think that existing cmos will be able to exist in future?

Regardless of improvements, CMOS technology is very likely to dominate the semiconductor industry and will continue to evolve in the near future. Even in the present day of advanced CMOS, older TTL, RTL, and RTL designs are still able to find their markets. We can however, nevertheless, conclude that a newer and better approach will displace majority of current semiconductors. 

that would be my answer.