{"667726":{"#nid":"667726","#data":{"type":"event","title":"MS Defense by Ram\u00f3n Alfonso Sosa","body":[{"value":"\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003E\u003Cspan\u003ETHE SCHOOL OF MATERIALS SCIENCE AND ENGINEERING\u003Cbr \/\u003E\r\nGEORGIA INSTITUTE OF TECHNOLOGY\u003C\/span\u003E\u003C\/strong\u003E\u003Cbr \/\u003E\r\n\u003Cspan\u003EUnder the provisions of the regulations for the degree\u003Cbr \/\u003E\r\nMASTER OF SCIENCE\u003Cbr \/\u003E\r\n\u003Cstrong\u003Eon Friday, May 12th, 2023\u003C\/strong\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003E\u003Cspan\u003E12:00 PM EST\u003C\/span\u003E\u003C\/strong\u003E\u003Cbr \/\u003E\r\n\u003Cspan\u003Evia\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003ETeams\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Ca href=\u0022https:\/\/teams.microsoft.com\/l\/meetup-join\/19%3ameeting_MzM2YWU3ZmUtOGI5Zi00NDk0LTliNjEtODlkMDQ1N2QyMTZm%40thread.v2\/0?context=%7b%22Tid%22%3a%22482198bb-ae7b-4b25-8b7a-6d7f32faa083%22%2c%22Oid%22%3a%2228686a29-7af6-4de4-b491-c7de35808ecd%22%7d\u0022\u003Ehttps:\/\/teams.microsoft.com\/l\/meetup-join\/19%3ameeting_MzM2YWU3ZmUtOGI5Zi00NDk0LTliNjEtODlkMDQ1N2QyMTZm%40thread.v2\/0?context=%7b%22Tid%22%3a%22482198bb-ae7b-4b25-8b7a-6d7f32faa083%22%2c%22Oid%22%3a%2228686a29-7af6-4de4-b491-c7de35808ecd%22%7d\u003C\/a\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EMeeting ID: 288 847 186 38\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EPasscode: tATXiZ\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003Ewill be held the\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EMASTER\u2019S THESIS DEFENSE\u003Cbr \/\u003E\r\nfor\u003Cbr \/\u003E\r\nRam\u00f3n Alfonso Sosa\u003Cbr \/\u003E\r\n\u0026nbsp;\u003Cbr \/\u003E\r\n\u201c\u003Cstrong\u003EA MAP TO RELIABLE CHIP-TO-PACKAGE CU-PILLAR INTERCONNECTIONS WITH SINTERED NANOPOROUS-CU CAPS\u003C\/strong\u003E\u201d\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cbr \/\u003E\r\n\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u0026nbsp;\u003Cbr \/\u003E\r\n\u0026nbsp; Committee Members:\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EDr. Vanessa Smet, ME (Co-Advisor)\u003Cbr \/\u003E\r\nDr. Antonia Antoniou, ME (Co-Advisor)\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EDr. Rao Tummala, ECE (Co-Advisor)\u003Cbr \/\u003E\r\nDr. Preet Singh, MSE\u003C\/span\u003E\u003Cbr \/\u003E\r\n\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003E\u003Cspan\u003EAbstract\u003C\/span\u003E\u003C\/strong\u003E\u003Cspan\u003E: With a continuous drive towards increased performance and miniaturization pushing the frontiers of system-level integration, emerging high-performance computing systems will require chip-to-substrate interconnection solutions that can reliably operate at higher operating temperatures (\u0026gt;100\u003C\/span\u003E\u003Cspan\u003E\u003Cspan\u003E\u2103\u003C\/span\u003E\u003C\/span\u003E\u003Cspan\u003E), current densities (\u0026gt;106 A\/cm2), and at finer pitches (\u0026lt;20 \u00b5m) expected in these architectures, well beyond the fundamental limits of traditional solder-based interconnections. All-Cu interconnections, the natural next off-chip interconnection node, have been successfully implemented at the foundry level via the now mature hybrid bonding process, though its reliance on expensive chemical-mechanical planarization (CMP) processes and material incompatibilities preclude it from being used at the package level, where the levels of non-coplanarity and warpage that exist cannot be addressed in this manner. Thus, there exists a need for an all-Cu interconnection technology with enhanced tolerance to non-coplanarities that can be used at the chip-to-substrate level.\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003ESintered Nanoporous-Cu interconnections are proposed in this research to address this grand challenge. Nanoporous-Cu (NP-Cu) is a spongelike material with an elastic modulus an order of magnitude lower than that of bulk-Cu, giving it enhanced compliance during assembly and allowing it to readily deform under modest pressures to accommodate package-level non-coplanarities. Additionally, the nanoscale structure of NP-Cu allows it to sinter at low temperatures, and is not reliant on organic stabilizers, unlike nanoscale particle systems, minimizing the risk of voiding due to volatiles. \u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EThis thesis presents two parallel thrusts in demonstrating the applicability of nanoporous-Cu as a suitable bonding interface material for chip-to-substrate all-Cu interconnections. The first is a demonstration of the manufacturability of nanoporous-Cu, which can be fabricated through an in-house designed electrodeposition process at fine-pitch of a Cu-Zn precursor alloy and subsequent chemical dealloying of this precursor. An extensive characterization of the wafer-scale Cu-Zn bumping process is presented, including the global, local, and within bump variations in composition of the electrodeposited Cu-Zn precursor, and a study that characterizes the incidence of nodule-type defects on these Cu-Zn bumps. \u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EThe second thrust is an exploration of the bonding parameter space for the formation of robust sintered NP-Cu interconnections. Through this study, the conventional thermocompression bonding process, which relies on extensive time under pressure, commonly used for direct Cu-Cu bonding is replaced by a hot-placement and pressureless sintering approach, which yields low-resistance, high-strength sintered NP-Cu interconnections at modest temperatures and lower placement pressures compared to bulk-Cu bonding. Finally, an evaluation of the reliability of these sintered NP-Cu interconnections under thermal aging, electromigration testing, and thermal cycling testing is presented. \u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; In summary, this work provides a pathway for reliable, fine-pitch all-Cu interconnections at the package level with enhanced tolerance to non-coplanarities using sintered nanoporous-Cu as a bonding interface material.\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u201c\u003Cstrong\u003EA MAP TO RELIABLE CHIP-TO-PACKAGE CU-PILLAR INTERCONNECTIONS WITH SINTERED NANOPOROUS-CU CAPS\u003C\/strong\u003E\u201d\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n","format":"limited_html"}],"field_summary_sentence":[{"value":"\u201cA MAP TO RELIABLE CHIP-TO-PACKAGE CU-PILLAR INTERCONNECTIONS WITH SINTERED NANOPOROUS-CU CAPS\u201d"}],"uid":"27707","created_gmt":"2023-05-11 20:25:11","changed_gmt":"2023-05-11 20:25:11","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2023-05-12T12:00:00-04:00","event_time_end":"2023-05-12T14:00:04-04:00","event_time_end_last":"2023-05-12T14:00:04-04:00","gmt_time_start":"2023-05-12 16:00:00","gmt_time_end":"2023-05-12 18:00:04","gmt_time_end_last":"2023-05-12 18:00:04","rrule":null,"timezone":"America\/New_York"},"location":"TEAMS","extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"111531","name":"ms defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"},{"id":"174045","name":"Graduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}