High-density high-reliability tungsten interconnection by filled interconnect groove metallization

• Published in: IEEE transactions on electron devices Vol. 35; no. 7; pp. 952 - 956
• Main Authors: Broadbent, E.K., Flanner, J.M., Van den Hoek, W.G.M.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.07.1988; Institute of Electrical and Electronics Engineers
• Subjects: Aluminum; Applied sciences; Chemical vapor deposition; Conductivity; Conductors; Dielectrics; Displays; Electromigration; Electronics; Etching; Exact sciences and technology; Integrated circuits; Metallization; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Tungsten; Metallizing; Laminated structure; Adhesion; Chemical vapor deposition; Electrical connection; Engraving; Internal stress; Technology; Tungsten; Integrated circuit; Groove; Silicon; Film resistor; Planar technology
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/16.3350

A novel multilevel metallization scheme has been developed that uses tungsten for the primary level of interconnection. Grooves that are 1- mu m wide and 2.0- mu m deep, corresponding to a level of line conductor interconnection, are pattern-etched into a planar layer of oxide dielectric. They are filled by isotropically depositing a blanket layer of pure tungsten using low-pressure chemical vapor deposition (CVD), followed by etch-back of the tungsten to produce a filled-interconnection-groove (FIG) conductor structure. Fabricated FIG conductors display an average sheet resistivity of 48 m Omega /square, comparable to conventional aluminum conductors. In addition, FIG metallization provides excellent planarity and greatly improved electromigration strength, and it facilitates the use of stacked vias.< >