Method for fabricating a spring structure on a substrate

Abstract

Efficient methods for lithographically fabricating spring structures onto a substrate containing contact pads or metal vias by forming both the spring metal and release material layers using a single mask. Specifically, a pad of release material is self-aligned to the spring metal finger using a photoresist mask or a plated metal pattern, or using lift-off processing techniques. A release mask is then used to release the spring metal finger while retaining a portion of the release material that secures the anchor portion of the spring metal finger to the substrate. When the release material is electrically conductive (e.g., titanium), this release material portion is positioned directly over the contact pad or metal via, and acts as a conduit to the spring metal finger in the completed spring structure. When the release material is non-conductive, a metal strap is formed to connect the spring metal finger to the contact pad/via.

Dependencies are inferred from the claim text.