Integrated circuit chip with pyramid or cone-shaped conductive pads for flexible C4 connections and a method of forming the integrated circuit chip

摘要

Disclosed is a chip and method of forming the chip with improved conductive pads that allow for flexible C4 connections with a chip carrier or with another integrated circuit chip. The pads have a three-dimensional geometric shape (e.g., a pyramid or cone shape) with a base adjacent to the surface of the chip, a vertex opposite the base and, optionally, mushroom-shaped cap atop the vertex. Each pad can include a single layer of conductive material or multiple layers of conductive material (e.g., a wetting layer stacked above a non-wetting layer). The pads can be left exposed to allow for subsequent connection to corresponding solder bumps on a chip carrier or a second chip. Alternatively, solder balls can be positioned on the conductive pads to allow for subsequent connection to corresponding solder-paste filled openings on a chip carrier or a second chip.

主权项

1. A method of forming an integrated circuit chip, said method comprising:
providing a semiconductor substrate having a first surface and a second surface opposite said first surface; forming a device at said first surface; and forming a conductive pad having a three-dimensional geometric shape with a base, a vertex opposite said base, and a cap on said vertex, said conductive pad being formed adjacent to any one of said first surface and said second surface and said forming of said conductive pad comprising forming said conductive pad such that said conductive pad comprises a first metal layer with oxidized sidewalls and a second metal layer stacked on said first metal layer and having conductive sidewalls.