We have developed methods for wafer level MEMS encapsulation by using low temperature direct bonding. Such packaging method is fast, provides a hermetic seal, does not require intermediate layers such as metals or adhesives and is IC-compatible. Strong bonding between the cap wafer and the device wafer can be obtained at temperatures below 200°C, which is than required in anodic bonding, and in direct bonding no high voltage is required. However, the problem in the direct bonding is that the surfaces to be bonded should be extremely clean and flat for spontaneous bonding to occur. For this purpose we have studied different methods for surface planarization and smoothing as well as for surface protection.
|Title of host publication||16th Micromechanics Europe Workshop|
|Subtitle of host publication||Book of abstracts|
|Place of Publication||Göteborg|
|Publication status||Published - 2005|
|Event||16th Micromechanics Europe Workshop, MME05 - Göteborg, Sweden|
Duration: 4 Sep 2005 → 6 Sep 2005
|Conference||16th Micromechanics Europe Workshop, MME05|
|Period||4/09/05 → 6/09/05|
- wafer scale packaging
- wafer bonding
Suni, T., Henttinen, K., Dekker, J., Luoto, H., Kulawski, M., & Kattelus, H. (2005). Wafer scale encapsulation of MEMS by direct bonding. In 16th Micromechanics Europe Workshop: Book of abstracts (pp. 119-122).