Non-magnetic package and method of manufacture
View Patent ↗A non-magnetic hermetic package includes walls that surround an open cavity, with a generally planar non-magnetic and metallic seal ring disposed in a continuous loop around upper edges of the walls; a sensitive component that is bonded within the cavity; and a non-magnetic lid that is sealed to the seal ring to close the cavity by a metallic seal.
1. A micro-electro-mechanical (MEMS) package comprising:
a non-magnetic package body comprising:
a floor; and
a wall extending from the floor and surrounding a cavity;
a non-magnetic seal ring formed on an upper edge of the wall;
a MEMS device mounted to the floor via an indium preform; and
a non-magnetic metallic lid hermetically sealed to the package body by the seal ring, the non-magnetic metallic lid comprising a molybdenum substrate coated with layers of copper and palladium.
2. The MEMS package of claim 1 further comprising:
electrical contacts extending through the floor and wirebonded to the MEMS device; and
external pins formed on the wall and electrically connected with each other via the MEMS device and the electrical contacts.
3. The MEMS package of claim 1 wherein the non-magnetic metallic lid consists of non-magnetic elements.
4. The MEMS package of claim 1 wherein the cavity is filled with clean dry air having an approximately atmospheric oxygen concentration.
5. A micro-electro-mechanical (MEMS) package comprising:
a non-magnetic package body comprising:
a floor; and
a wall extending from the floor and surrounding a cavity;
a non-magnetic seal ring formed on an upper edge of the wall;
a MEMS device mounted to the floor via an indium preform; and
a non-magnetic metallic lid hermetically sealed to the package body by the seal ring, the non-magnetic metallic lid comprising a molybdenum substrate and a gold/tin solder preform that extends around an outer periphery of a sealing surface thereof.
6. The MEMS package of claim 5 wherein the gold/tin solder preform comprises a fillet that extends up over an outer edge of the non-magnetic metallic lid.
7. A micro-electro-mechanical (MEMS) package comprising:
a package body comprising a floor and a wall extending upward therefrom;
a seal ring formed on an upper surface of the wall of the package body;
a lid coupled to the package body via a hermetic seam seal formed between the lid and the seal ring, the lid comprising a non-magnetic metallic lid comprising a molybdenum substrate coated with layers of copper and palladium;
a MEMS device mounted within a hermetically sealed cavity formed between the package body and the lid; and
a low temperature solder coupling the MEMS device to the package body, the low temperature solder comprising indium;
wherein the package body, the seal ring, and the lid consist of non-magnetic elements.