A New Packaging Method of Alkali Metal Simple Substrate and Related Key Techniques
A new method of packaging alkali metals is demonstrated in this paper.The vapor cells,which contain the simple substrate of alkali metals,are usually the key part of MEMS atomic devices like micro atomic clocks or micro magnetometers.Alkali metal is extremely active with oxygen and water,and its color will change dramatically when exposed in atmosphere.The active feature of alkali metals makes it incompatible with some necessary MEMS process since the instruments are not oxygen-proof.Recent way of using alkali compounds to generate alkali metal simple substrate will cause frequency-shift and inaccuracy in the performance of atomic devices.By using paraffin to packet the simple substrate of alkali metals,rubidium for example,the oxidation and deterioration of the metal can be avoided,thus making it easier to transfer Alkali metals into the vapor cells.It has also been reported that paraffin can serve as a wall-coating material for the vapor cells,helping to improve the Q-factor and the long-term frequency stability of the atomic devices.The process of manufacturing the package is introduced along with the related key technologies.Laser beam method and needle mold method are discussed to make blind holes on the paraffin wax layer.Paraffin packages containing radium simple substrate has been achieved,ranging from 0.9mm3 to 1.6mm3 in size,with the smallest one containing 0.2 L of radium inside.The sealing performance of the package has been tested in a one-month (30 days) test and proves to work well by judging from the color of the sealed metal.A low-temperature anodic bonding process is introduced for the fabrication,to make the paraffin package compatible with this key process of making a vapor cell.
alkali metal packets atomic vapor cells MEMS atomic devices
CHEN Shuo RUAN Yong MA Bo
State Key Laboratory of Precision Measurement Technology and Instruments, TsinghuaUniversity, Beijing 100084, China
国际会议
中国微米纳米技术学会第14届学术年会、第3届国际年会暨第6届微米纳米技术“创新与产业化国际研讨与展览会(CSMNT2012 & ICMAN2012)
杭州
英文
1-6
2012-11-04（万方平台首次上网日期，不代表论文的发表时间）