Reverse pillar and maskless contact-two novel recessed metal schemes and their comparisons to conventional VLSI metallization schemes

Two novel metallization schemes, reverse pillar and maskless contact, based on the recessed metal approach, are discussed. The reverse-pillar process offers a self-aligned headless contact for optimum layout. The maskless contact scheme removes the need for a contact lithographic step. The schemes are compared to the conventional metallization schemes. Both the advantages and disadvantage of the schemes are discussed. Both schemes offer the advantages of planarization and easy integration into standard multilevel metal approaches.<>