HERMETICALLY SEALED THROUGH VIAS (TVS)

摘要

Hermetically sealed through vias (TVs) are disclosed. In one aspect, an hourglass TV is first created in a substrate. The hourglass TV has a waist opening. A conductive conformal coating covers at least a portion of an interior wall of the hourglass TV. The conductive conformal coating also completely fills the waist opening to provide a hermetic seal between an upper opening and a lower opening of the hourglass TV, thus creating the hermetically sealed TV. The combination of the hourglass shape, which provides a narrowing waist, and using the conformal coating process, facilitates the natural accumulation of the conductive conformal coating material in and about the waist opening. Creating hermetically sealed TVs in this manner leads to lower costs, shortened process and plating times, and increased production throughput compared to conventional processes for creating the hermetically sealed TVs in substrates.

主权项

1. An apparatus comprising a substrate having at least one hourglass through via (TV) comprising:
an hourglass-shaped cross section that extends between an upper opening on a top surface of the substrate and a lower opening on a bottom surface of the substrate; an upper cavity that extends between the upper opening and a waist opening, which is inside the at least one hourglass TV and between the upper opening and the lower opening; a lower cavity that extends between the lower opening and the waist opening, wherein the waist opening has a width that is less than a width of the upper opening and a width of the lower opening; and a conductive conformal coating that covers at least a portion of an interior wall of the at least one hourglass TV and fills the waist opening to provide a hermetic seal between the upper opening and the lower opening.