Composition-Tunable Properties of Cu(Ag) Alloy for Hybrid Bonding Applications
In the present study, the properties of Cu(Ag) alloy films were studied to evaluate their potential use as an alternate material for interconnection in hybrid bonding. Thin alloy films of Cu(Ag) were deposited by pulsed electrochemical deposition (PED) using a sulfuric acid-based bath, rotating disk...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-12-01
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| Online Access: | https://www.mdpi.com/1996-1944/16/23/7481 |
| _version_ | 1797399881466249216 |
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| author | Sarabjot Singh Kathleen Dunn |
| author_facet | Sarabjot Singh Kathleen Dunn |
| author_sort | Sarabjot Singh |
| collection | DOAJ |
| description | In the present study, the properties of Cu(Ag) alloy films were studied to evaluate their potential use as an alternate material for interconnection in hybrid bonding. Thin alloy films of Cu(Ag) were deposited by pulsed electrochemical deposition (PED) using a sulfuric acid-based bath, rotating disk electrode, and hot entry. Secondary ion mass spectrometry (SIMS) was used to measure the silver content of the films, with us finding that it decreases with increasing duty cycle. Thereafter, bright field scanning transmission electron microscope (STEM) imaging in combination with energy-dispersive x-ray spectroscopy (EDS) was used to visualize the thin film microstructure and to confirm the uniform distribution of silver throughout the film, with no bands being seen despite the pulsed nature of the deposition. Film resistance was measured by a four-point probe to quantify the impact of Ag content on resistivity, with us finding the expected linear relationship with the Ag content in the film. Furthermore, the coefficient of thermal expansion (CTE) of the films was measured using X-ray diffraction, and modulus and hardness were measured via nanoindentation, revealing linear dependences on the Ag content as well. Notably, the addition of 1.25 atom% Ag resulted in a significant increase in the CTE from 17.9 to 19.3 ppm/K, Young’s modulus from 111 to 161 GPa, and film hardness from 1.70 to 3.99 GPa. These simple relationships offer a range of properties tunable via the duty cycle of the pulsed plating, making Cu(Ag) a promising candidate for engineering wafer-to-wafer metal interconnections. |
| first_indexed | 2024-03-09T01:46:33Z |
| format | Article |
| id | doaj.art-02cc5e07c5c340eabaad30395929e171 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-09T01:46:33Z |
| publishDate | 2023-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-02cc5e07c5c340eabaad30395929e1712023-12-08T15:21:24ZengMDPI AGMaterials1996-19442023-12-011623748110.3390/ma16237481Composition-Tunable Properties of Cu(Ag) Alloy for Hybrid Bonding ApplicationsSarabjot Singh0Kathleen Dunn1Department of Nanoscale Science and Engineering, University at Albany, State University of New York, Albany, NY 12203, USADepartment of Nanoscale Science and Engineering, University at Albany, State University of New York, Albany, NY 12203, USAIn the present study, the properties of Cu(Ag) alloy films were studied to evaluate their potential use as an alternate material for interconnection in hybrid bonding. Thin alloy films of Cu(Ag) were deposited by pulsed electrochemical deposition (PED) using a sulfuric acid-based bath, rotating disk electrode, and hot entry. Secondary ion mass spectrometry (SIMS) was used to measure the silver content of the films, with us finding that it decreases with increasing duty cycle. Thereafter, bright field scanning transmission electron microscope (STEM) imaging in combination with energy-dispersive x-ray spectroscopy (EDS) was used to visualize the thin film microstructure and to confirm the uniform distribution of silver throughout the film, with no bands being seen despite the pulsed nature of the deposition. Film resistance was measured by a four-point probe to quantify the impact of Ag content on resistivity, with us finding the expected linear relationship with the Ag content in the film. Furthermore, the coefficient of thermal expansion (CTE) of the films was measured using X-ray diffraction, and modulus and hardness were measured via nanoindentation, revealing linear dependences on the Ag content as well. Notably, the addition of 1.25 atom% Ag resulted in a significant increase in the CTE from 17.9 to 19.3 ppm/K, Young’s modulus from 111 to 161 GPa, and film hardness from 1.70 to 3.99 GPa. These simple relationships offer a range of properties tunable via the duty cycle of the pulsed plating, making Cu(Ag) a promising candidate for engineering wafer-to-wafer metal interconnections.https://www.mdpi.com/1996-1944/16/23/7481pulsed electrochemical deposition (PED)Cu(Ag) alloythin filmshybrid bonding interconnections |
| spellingShingle | Sarabjot Singh Kathleen Dunn Composition-Tunable Properties of Cu(Ag) Alloy for Hybrid Bonding Applications Materials pulsed electrochemical deposition (PED) Cu(Ag) alloy thin films hybrid bonding interconnections |
| title | Composition-Tunable Properties of Cu(Ag) Alloy for Hybrid Bonding Applications |
| title_full | Composition-Tunable Properties of Cu(Ag) Alloy for Hybrid Bonding Applications |
| title_fullStr | Composition-Tunable Properties of Cu(Ag) Alloy for Hybrid Bonding Applications |
| title_full_unstemmed | Composition-Tunable Properties of Cu(Ag) Alloy for Hybrid Bonding Applications |
| title_short | Composition-Tunable Properties of Cu(Ag) Alloy for Hybrid Bonding Applications |
| title_sort | composition tunable properties of cu ag alloy for hybrid bonding applications |
| topic | pulsed electrochemical deposition (PED) Cu(Ag) alloy thin films hybrid bonding interconnections |
| url | https://www.mdpi.com/1996-1944/16/23/7481 |
| work_keys_str_mv | AT sarabjotsingh compositiontunablepropertiesofcuagalloyforhybridbondingapplications AT kathleendunn compositiontunablepropertiesofcuagalloyforhybridbondingapplications |