Design Of MEMS Chip-Scale Atomic Clock And Hermetic Packaging Of Cs/Rb Vapor

The Atomic Clock is developed for the precision and the chip-scale, since the first Atomic Clock was built in 1949. There are huge demands for the Chip-Scale Atomic Clock in the communion, traffic, power transmission, financial settlement, national defence, aviation and the measurement of the other physics parameter. The CSAC will bring a profound influence in the development of the world. CSAC is a topic focused by many researchers in many countries. The quantum mechanics, coherent optics, high frequency electrocircuit design, MEMS process and laser technology are necessary for the CSAC, which is a long-term, cross-subject, complicated and system level research.Based on the fundamental quantum mechanics of the CSAC, the matrix equations, the compare of different atomic clocks and the coherent population trapping(CPT) theory are studied in details. Experimental studies about the fabrication of the package of Cs/Rb vapor are also carried out according to the MEMS process. After the Helium leak detection, shear strength test and thermal shock test, the leakage rate is calculated and discussed with a simplified seepage model. The leakages of the silicon-silicon and silicon-glass bonding with the benzo-cyclo-butene(BCB) material at 250℃ were better than the ones of the anodic bonding at 300℃. The shear strength and the yields of the bonding samples are enough for MEMS package. The leakage and shear strength were still good, which shows that using the BCB material is a effective way for wafer level low-temperature hermetic package. The study has provided the experimental results for the further researches of the CSAC.