Wafer-level hermetic vacuum packaging by bonding with a copper–tin thin film sealing ring

摘要: A wafer-level hermetic vacuum packaging technology intended for use with MEMS devices was developed based on a copper–tin (CuSn) thin film sealing ring. To allow packaging, the shear strength of CuSn bond improved by optimizing pretreatment conditions. As result, an average 72.3 MPa obtained and cavity that had been hermetically sealed using (WLP) maintained its 1.84 years. The total pressures in cavities partial residual gases were directly determined ultra-low outgassing gas analyzer (RGA) system. Hermeticity evaluated helium leak rates, which calculated from RGA resulting data showed following years storage pressure 83.1 Pa, contained argon as main exhibited rate low 1.67 × 10−17 Pa m3 s−1, corresponding to air 6.19 10−18 s−1. demonstrate WLP ring permits ultra-high hermeticity conjunction long-term is applicable devices.