Luobin Zhang,Jintao Wang,Sheng Zhou,Xiaojia Luo,Yufeng Li
This research is an attempt to apply the silver thick-film metallization and the soft soldering process to the ultra-high vacuum packaging of atom chips with through silicon via (TSV). During the packaging process, a vacuum environment is used to avoid oxidation of the Cu layer on the chip during heating. At the same time, tin foil is used to protect the inner wall of the glass cell to prevent the gas emitted by the solder from polluting the inner wall. In general, by the adoption of screen printing, sintered surface metallization at a constant temperature of 450–500 °C for 5 min, combined with soft soldering, the packaging of an atom chip with TSV and a silica glass cell is realized. The weld gap is less than 50 μm, the airtightness can reach 8.5 × 10 −13 Pa m 3 /s, and the vacuum degree can reach 2.18 × 10 −8 Pa. That can meet the requirements of cold atom experiment for light path and vacuum degree.
Low-temperature cofired ceramic (LTCC) materials are a promising material for heat dissipation substrates due to their excellent thermal conductivity and thermal expansion coefficient similar to that of silicon. However, the difficulties in surface metallization techniques limit its application. This work uses Bi–B–Si–Zn–Al glass/ceramic composite as the substrate and Bi–B–Si–Zn–Al glass powder as the inorganic binder for silver pastes. The silver thick film with a glass content of 3 wt% is sintered at 800 °C for 30 min, and the samples have excellent electrical conductivity (surface square resistance of 0.29 mΩ £ −1 ) and mechanical properties (interface bonding force of 17.56 MPa). In addition, the introduction of CuO into the glass phase can inhibit the silver diffusion phenomenon during the sintering process and improve the conductive performance of the material. The results are beneficial for the preparation and application stability of LTCC devices.
危险品化学品经营许可证（带存储）