US Patent 7427527 - MEMS alignment using solder reflow

http://www.freepatentsonline.com/7427527.html

The integration of different MEMS devices together requires careful alignment critical to such applications as optical switching arrays. This patent from Surfect Technologies teaches a new technique using magnetic fields to manipulate solder used in the alignment of MEMS. Claim 1 reads:

1. A method for aligning one or more MEMS devices, the method comprising the steps of:

depositing solder comprising ferromagnetic particles on a first MEMS device;

disposing the first MEMS device on a stage;

reflowing the solder;

placing a second MEMS device adjacent to the solder;

modifying a distribution of the particles in the solder, thereby moving the second MEMS device relative to the first MEMS device;

measuring the relative alignment of the MEMS devices; and

solidifying the solder when the desired relative alignment is achieved.