eprintid: 1578 rev_number: 10 eprint_status: archive userid: 12 dir: disk0/00/00/15/78 datestamp: 2016-05-25 03:06:17 lastmod: 2016-05-25 03:09:42 status_changed: 2016-05-25 03:06:17 type: article metadata_visibility: show creators_name: Feng, Wei creators_name: Bui, Thanh Tung creators_name: Watanabe, Naoya creators_name: Shimamoto, Haruo creators_name: Aoyagi, Masahiro creators_name: Kikuchi, Katsuya creators_id: tungbt@vnu.edu.vn title: Fabrication and stress analysis of annular-trench-isolated TSV ispublished: inpress subjects: ECE subjects: ElectronicsandComputerEngineering subjects: isi divisions: fac_fet abstract: The large mismatches among the coefficients of thermal expansion (CTE) of the metal via, insulator liner, and Si substrate of the through-silicon via (TSV) induce thermal stresses within and around the TSV during thermal-cycled fabrication processes. Reduction of thermal stress in the Si substrate is important for minimizing the deviations in the device characteristics. An annular-trench-isolated (ATI) structure was proposed for the TSV to solve the thermal issues, which occur during the three-dimensional (3D) integrated circuit (IC) integration, by stress redistribution. The concept of ATI TSV is based on retaining a Si-ring between the metal core and insulator layer during the fabrication process. We realized the ATI TSV using a via-last fabrication approach, with two deep silicon etching processes (Bosch processes) for the insulator layer and the metal core. Parylene-HT was utilized as the insulator to achieve high uniformity. With a vacuum-assisted filling system, the vias were filled with a solder material. ATI TSVs with diameters of 10 μm and 2-μm-thick Parylene-HT insulation layers were demonstrated. Studies on the thermal stress levels of the ATI TSV were carried out by finite-element method (FEM) simulation, along with comparisons with regular and annular TSVs. We revealed that the ATI TSV shows lower thermal stresses in the Si substrate than the regular and annular TSVs. The ATI TSV is a possible candidate for 3D IC integration with stress-sensitive devices. date: 2016-05-01 date_type: published publisher: Elsevier full_text_status: public publication: Microelectronics Reliability refereed: TRUE issn: 0026-2714 citation: Feng, Wei and Bui, Thanh Tung and Watanabe, Naoya and Shimamoto, Haruo and Aoyagi, Masahiro and Kikuchi, Katsuya (2016) Fabrication and stress analysis of annular-trench-isolated TSV. Microelectronics Reliability . ISSN 0026-2714 (In Press) document_url: https://eprints.uet.vnu.edu.vn/eprints/id/eprint/1578/1/Abstract.docx