Effect of Ar Sputtering Pretreatment on the Electromigration Resistance in Al-Cu/TiN/Ti Interconnects

Autor: A. Chuang, L.T. Lin, L.P. Wang, J. Hwang, K. Perng, F.S. Huang
Rok vydání: 1998
Předmět:
Zdroj: MRS Proceedings. 516
ISSN: 1946-4274
0272-9172
Popis: The 1 µm-wide Al-0.5wt%Cu/TiN/Ti interconnect, on the oxidized Si(100) wafer without Al sputtering pretreatment on the SiO2 surface prior to Ti deposition, failed after stressing with a current density of 1 × 106 A/cm2 for 190 hr at 175°C. In contrast, the interconnect with Ar sputtering pretreatment did not fail after stressing under the same condition for 550 hr. X-ray diffraction spectra indicated that the Ar sputtering pretreatment lowered Al(111) peak intensity down to 1/46 of its magnitude. This result suggests that the improvement of electromigration resistance by Ar sputtering pretreatment is not due to Al(111) texture, which is opposite to the result of Shibata et al. (Jpn. J. Appl. 32, 4479 (1993)). The elemental concentration distribution in depth was characterized on Al-Cu/TiN/Ti multilayers with and without Ar sputtering pretreatment by using secondary ion mass spectroscopy and Auger electron microscopy. A fairly large amount of oxygen and nitrogen was found to segregate near the Al-Cu/TiN interface. The phenomenon associated with the large amount of segregated oxygen and nitrogen is attributed to the enhancement of electromigration resistance.
Databáze: OpenAIRE
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