Method for self-aligning solder-attached mems die to a mounting surface
A method of attaching a MEMS die to a surface includes centering and rotationally aligning a solder perform on a solder surface of a body, centering and rotationally aligning a MEMS die on the solder preform, and heating the solder perform in a reflow process until the solder is molten and surface tension of the molten solder moves the MEMS die to a position where the surface tensions balance, and the MEMS die is centered on, and rotationally aligned with, the solder surface of the body.
1. A method of attaching a MEMS die to a surface, the method comprising:
forming a solder well in a center of a solder surface of a body;
centering and rotationally aligning a solder perform within the solder well;
centering and rotationally aligning a MEMS die on the solder preform; and
heating the solder perform in a reflow process until the solder is molten and surface tension of the molten solder moves the MEMS die to a position where the surface tensions balance, and the MEMS die is centered within the solder well;
wherein the solder surface of the body is substantially circular and the solder preform is substantially rectangular.
2. The method of attaching a MEMS die to a surface according to claim 1 , wherein the solder well is substantially rectangular.
3. The method of attaching a MEMS die to a surface according to claim 1 , wherein the solder perform has a hole formed centrally therethrough.
4. A method of attaching a MEMS die to a surface, the method comprising:
forming a solder well in a center of a solder surface of a body, the solder well including a lip formed therein and extending circumferentially around a bore in the body;
centering and rotationally aligning a solder perform within the solder well;
centering and rotationally aligning a MEMS die on the solder preform; and
heating the solder perform in a reflow process until the solder is molten and surface tension of the molten solder moves the MEMS die to a position where the surface tensions balance, and the MEMS die is centered within the solder well;
wherein the lip defines a barrier over which the molten solder will not flow during the heating step, the lip thus preventing the molten solder from flowing into the bore.