A CMOS Molecular Clock Probing 231.061-GHz Rotational Line of OCS with Sub-PPB Long-Term Stability and 66-MW DC Power

Abstract

© 2018 IEEE. Recent progress of on-chip spectroscopic systems enables a new set of highly-stable frequency references (i.e. clocks) with low cost, power and volume. It is based on the rotational spectrum of gaseous molecules in sub-THz regime, a physical mechanism alternative to that in traditional atomic clocks. This scheme also enables fast start-up operation and robustness against mechanical vibration and external electromagnetic fields. This paper demonstrates the first chip-scale molecular clock in 65nm CMOS which probes the 231.061GHz spectral line of Carbonyl Sulfide ( 16 O 12 C 32 S). The clock consumes only 66mW DC power and has a measured Allan deviation of 3.8×10- 10 with an averaging time of τ=10 3 s.