Ordonez Juan, Dautel Philip, Schuettler Martin, Stieglitz Thomas
Laboratory for Biomedical Microtechnology, Dept. of Microsystems Engineering-IMTEK, Univ. of Freiburg, Germany.
Annu Int Conf IEEE Eng Med Biol Soc. 2012;2012:2784-7. doi: 10.1109/EMBC.2012.6346542.
Micro-packages based on alumina ceramics hermetically sealed with glass solder were fabricated and tested over a 1.5 years period under accelerated aging at 85 °C. A device for sealing the 1.2 mm high, and ø10mm packages while cooling the critical centre of the package containing the electronics was developed. Heating of the rim up to 550 °C while maintaining the package centre below 300°C was successful, allowing a symmetrical heating of the device during the sealing procedure. The fabricated packages with an inner volume of 0.05 cc were backfilled with helium and tested for hermeticity with a fine leak tester. Samples passing the fine leak (1•10(-12) atm•cc/s) test were attached to a larger chamber containing a humidity sensor. Some devices covered in PDMS and some directly exposed were stored at 85 °C in water to measure the humidity intrusion into the device due to deterioration of glass solder. 1 out of the 8 successfully fabricated devices failed after 5 years extrapolated lifetime. Two of the devices have kept constant humidity levels while others gradually rise. Nevertheless, 7 out of 8 have maintained a level below 17,000 ppm humidity. Furthermore, the deterioration of glass solder was electrically and optically studied over a year's period showing no corrosion of glass if properly coated in PDMS.
制备了基于氧化铝陶瓷并用玻璃焊料气密密封的微型封装，并在85°C加速老化条件下进行了1.5年的测试。开发了一种用于密封1.2毫米高、直径10毫米封装的装置，同时冷却包含电子元件的封装关键中心。在将封装中心温度保持在300°C以下的同时，将边缘加热到550°C成功实现，使得在密封过程中装置能够对称加热。制备的内部体积为0.05立方厘米的封装用氦气回填，并使用精细检漏仪测试气密性。通过精细泄漏（1•10(-12) 大气压•立方厘米/秒）测试的样品连接到一个包含湿度传感器的较大腔室。一些覆盖有聚二甲基硅氧烷（PDMS）的器件和一些直接暴露的器件在85°C的水中储存，以测量由于玻璃焊料劣化导致的湿度侵入器件的情况。在8个成功制备的器件中，有1个在推算寿命5年后失效。其中2个器件的湿度水平保持恒定，而其他器件的湿度水平逐渐上升。尽管如此，8个器件中有7个的湿度水平保持在17,000 ppm以下。此外，在一年的时间里对玻璃焊料的劣化进行了电学和光学研究，结果表明，如果用PDMS适当涂覆，玻璃不会腐蚀。
