Freescale Semiconductor,inc.

Steven Markgraf

Owen R Fay

William H Lytle

Henry G Hughes

Craig S Amrine

Jong-Kai Lin

Ananda P De Silva

Stephen B Springer

An exemplary method and apparatus for MEMS device wafer level and/or array packaging comprises inter alia an EM shielding array of dielectric lid elements () sealed to a MEMS device die array () to produce a sealed MEMS device package array (). Disclosed features and specifications may be variously controlled, adapted or otherwise optionally modified to improve hermetic sealing and/or EM shielding for any MEMS device. An exemplary embodiment of the present invention representatively provides for wafer level packaging of RF MEMS switches prior to device singulation.

Wafer level MEMS packaging

A method is disclosed for encapsulating micromechanical elements or features on a substrate. In accordance with the method, a first substrate () is provided which has a patterned surface (). A seed metallization () is then deposited onto the patterned surface, and a structural material layer (), which preferably comprises copper, is electroplated onto the seed metallization. A solder (), such as SnCu, is electroplated onto the metal layer, and the seed metallization, the structural material layer and the solder are removed from the first substrate as a cohesive structure (), through the application of heat or by other suitable means, such that a negative replica of the patterned surface is imparted to the structure. The structure may then be placed on a second substrate () such that the solder is in contact with the second substrate, after which the solder is reflowed. Prior to reflow, the solder may be exposed to a fluorinated plasma, which forms a dry flux on the solder surface in the form of fluorinated metal oxides.

Low cost fabrication and assembly of lid for semiconductor devices

Growing community of inventors

Chandler, AZ, United States of America

Steven Markgraf