The Effect of Target Purities on Grain Growth in Sputtered Copper Thin Films
| Autor: | Masahiro Shimada, Susumu Tsukimoto, Masanori Murakami, Miki Moriyama, Toshifumi Morita |
|---|---|
| Rok vydání: | 2005 |
| Předmět: | |
| Zdroj: | MATERIALS TRANSACTIONS. 46:1036-1041 |
| ISSN: | 1347-5320 1345-9678 |
| DOI: | 10.2320/matertrans.46.1036 |
| Popis: | Grain growth rates in sputtered Cu thin films were found to be influenced by impurity levels of the sputtering targets. The Cu thin films with thickness of 100 nm or 1 μm were deposited on the rigid substrates by a sputter-deposition technique using the Cu target with purity of 99.99% (4N) or 99.9999% (6N), then subsequently annealed at room temperatures. The microstructures of the Cu films were analyzed by scanning-ion microscopy and the sheet resistivities was measured by a four-point probe method. Significant grain growth and reduction of the electrical resistivities was observed during room-temperature storage in these sputtered Cu films. For the Cu films with a thickness of 1 μm, the grain growth rates of the Cu films were not influenced by the impurity levels of the targets. However, for the films with a thickness of 100 nm, the rate of the grain growth in the 6N-Cu films was found to be slower than that in the 4N-Cu films. This was contradictory to the grain growth mechanism of bulk Cu. The grain growth rates of the Cu films at room temperature, which were strongly influenced by the existence of a small amount of impurities in the Cu films, were well explained by the difference of the strain relaxation mechanisms in the films. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|