Formation of through via before contact processing

摘要

The formation of through silicon vias (TSVs) in an integrated circuit (IC) die or wafer is described in which the TSV is formed in the integration process prior to contact or metallization processing. Contacts and bonding pads may then be fabricated after the TSVs are already in place, which allows the TSV to be more dense and allows more freedom in the overall TSV design. By providing a denser connection between TSVs and bonding pads, individual wafers and dies may be bonded directly at the bonding pads. The conductive bonding material, thus, maintains an electrical connection to the TSVs and other IC components through the bonding pads.

主权项

1. A method for forming one or more through vias comprising:
forming active devices on a front-side of a first wafer, the first wafer comprising a back-side opposite the front-side of the first wafer; forming one or more recesses in the first wafer prior to forming an interlayer dielectric (ILD) layer over the front-side of the first wafer, the one or more recesses extending from the front-side of the first wafer to a predetermined distance from the back-side of the first wafer; forming conductive material in the one or more recesses, the conducting material forming one or more through vias; forming a first contact connected to at least one of the one or more through vias; forming a first bonding pad connected to the first contact, wherein the first bonding pad is different from the first contact and wherein the first bonding pad comprises at least one sidewall in physical contact with a dielectric material; forming a dielectric layer over the back-side of the first wafer, wherein the forming of the dielectric layer is performed after the forming the conductive material; and forming a metallization layer within the dielectric layer over the back-side of the first wafer, the metallization layer comprising a second contact electrically connected to at least one of the one or more through vias and also being exposed to allow current to flow to at least one of the one or more through vias.