摘要 |
A method in integrated circuit technology of depositing an adherent aluminum film that does not develop significant protrusions, such as "hillocks" and "whiskers", during or following annealing. The aluminum is deposited by evaporation or sputtering techniques while sufficient dry oxygen is introduced periodically into the deposition chamber to form alernating layers of aluminum and oxygen-doped aluminum consisting of no more than 10 atomic percent oxygen. Photolithographically patterning such a laminated film into the appropriate configuration of conducting lines and bond pads, and subsequently annealing such as a laminated film at temperatures from 450 DEG C. to 560 DEG C. in forming gas, results in aluminum surfaces that are free of protrusions with heights above 0.5 mu m and in films that have relatively low resistivity, i.e., resistivity that is less than 1.8 times the resistivity of bulk aluminum. The laminated films range in thickness between 8000 to 25,000 angstroms. The top layer is formed of aluminum with a thickness no less than about 1500 angstroms and no more than about 3000 angstroms.
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