| Autor: |
Eswar Ramanathan, Zhiguo Sun, Vijaya Rana, Vijayalakshmi Seshachalam, Anbu Selvam Km Mahalingam, Chauhan Kripa Nidhan, Joseph F. Shepard, Tingge Xu, Minrui Wang, Mary Claire Silvestre, Yang Bum Lee |
| Rok vydání: |
2019 |
| Předmět: |
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| Zdroj: |
2019 China Semiconductor Technology International Conference (CSTIC). |
| Popis: |
In advanced technology nodes, Multi-color back end of line self-aligned via (SAV) integration involves a stack of dielectric and metallic thin films to memorize the pattern transferred from different color lithography masks. We see intermittent so-called “starburst” nuisance defects which causes yield loss and/or wafer scrap. We develop a hammer test method to enhance the detectability by inserting a higher stress metallic film and stressing the film stack in a repeated thermal cycle environment on hot plate. Physical failure analysis identifies the defect originates from the interface between spin on hard mask and dielectric thin film. Material analysis points the root cause of the issues are the marginal adhesion energy within the film stack, the thermal outgassing from the spin on lithography materials and the high compressive stress of the top metallic layer. Finally, through detailed material screening process, we narrow down to optimal film stack combinations and demonstrate positive results on patterned wafers. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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