Analysis of high frequency breakdown of noble gases in A MEMS-based Rb-87 lamp for miniaturized passive rubidium atomic clock

MEMS-based atomic clock is being studied by some investigtors and we are proposing and developing a miniaturized pass rubidium atomic clock, in which Rb-87 lamp is the first microdevice of the system. To make the lamp give off light, noble gas is needed to fill the lamp. In this paper, we study the high frequency breakdown of noble gases in a MEMS-based Rb-87 lamp for miniaturized passive rubidium atomic clock. Breakdown criteria equation is obtained from the Boltzmann transport equation. By solving the criteria equation, we obtain the minimum breakdown electric field for neon, argon and helium at different frequencies of RF field and with different heights of microcavity of the lamp. The results are analysed and frequency of 200MHz and height of 1.5mm, with neon or argon as the filled gas, are better choices for designing a MEMS-based Rb-87 lamp for passive rubidium atomic clock.