Multiple via structure and method

摘要

A method for forming a device with a multi-tiered contact structure includes forming first contacts in via holes down to a first level, forming a dielectric capping layer over exposed portions of the first contacts and forming a dielectric layer over the capping layer. Via holes are opened in the dielectric layer down to the capping layer. Holes are opened in the capping layer through the via holes to expose the first contacts. Contact connectors and second contacts are formed in the via holes such that the first and second contacts are connected through the capping layer by the contact connectors to form multi-tiered contacts.

主权项

1. A method for forming a device with a multi-tiered contact structure, the method comprising:
forming first contacts in first via holes down to a first level; forming a dielectric capping layer over exposed portions of the first contacts; forming a dielectric layer over the dielectric capping layer; opening second via holes in the dielectric layer down to the dielectric capping layer; opening connecting holes in the dielectric capping layer through the second via holes to expose the first contacts; forming a diffusion liner on sidewalls of the second via holes and the connecting holes, the diffusion liner leaving the first contacts in the first via holes exposed; forming contact connectors in the connecting holes formed in the dielectric capping layer, the contact connectors directly contacting the exposed first contacts; and forming second contacts in the second via holes directly over the contact connectors, the second contacts connected to the first contacts through the dielectric capping layer by the contact connectors to form multi-tiered contacts.