Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (24권4호 196-205)

A Study on the Thermal Stability in Multi-Aluminum Thin Films during Isothermal Annealing

등온 열처리시 알루미늄 다층 박막의 열적 안정성에 관한 연구

전진호;박정일;박광자;김홍대;김진영;

광운대학교 전자재료공학과;국립공업시험원 무기화학과;

Abstract

Multi-level thin films are very important in ULSI applications because of their high electromigration resistance. This study presents the effects of titanium, titanium nitride and titanium tungsten underlayers of the stability of multi-aluminum thin films during isothermal annealing. High purity Al(99.999%) films have been electron-beam evaporated on Ti, TiN, TiW films formed on SiO2/Si (P-type(100))-wafer substrates by RF-sputtering in Ar gas ambient. The hillock growth was increased with annealing temperatures. Growth of hillocks was observed during isothermal annealing of the thin films by scanning electron microscopy. The hillock growth was believed to appear due to the recrystallization process driven by stress relaxation during isothermal annealing. Thermomigration damage was also presented in thin films by grain boundary grooving processes. It is shown that underlayers of Al/TiN/SiO2, Al/TiW/SiO2 thin films are preferrable to Al/SiO2 thin film metallization.

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