Copper metallization based on direct-liquid-injection hot-wire CVD

• Published in: Microelectronic engineering 2007-05, Vol.84 (5), p.1148-1151
• Main Authors: Papadimitropoulos, G., Davazoglou, D.
• Format: Article
• Language: English
• Subjects: Applied sciences; Compound structure devices; Copper; Direct-liquid-injection; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; Hot-wire CVD; Metallization; Microelectronic fabrication (materials and surfaces technology); Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2007.01.012

It is presented for the first time a direct-liquid-injection hot-wire CVD system for copper chemical vapor deposition using hexafluoroacetylacetonate Cu(I) trimethylvinylsilane as precursor. The system enables: (a) the selective chemical vapor deposition (SCVD) and (b) the deposition of hot-wire CVD (HWCVD) copper films. Moreover, it enables the deposition of tungsten oxide films, which adhere well on the oxidized Si substrates, by heating the tungsten filament only in a hydrogen-containing ambient (hwHWO films). Cu films were selectively deposited (SCVD) on patterned hwHWO layers but these deposits were large-grained and had a very high electrical resistance. This effect was attributed to the semi-insulating nature of hwHWO films, which implies the presence of few free electrons on their surface necessary for the easy decomposition of the precursor molecules. Cu was SCVD on patterned hwHWO/HWCVD Cu “sandwiches” giving patterns with fine grains and electrical resistivity near that of the bulk metal.