Ultralow dielectric cross-linked silica aerogel nanocomposite films for interconnect technology. (August 2022)

• Record Type: Journal Article
• Authors: Choi, Haryeong; Kim, Taehee; Kim, Taeho; Moon, Sunil; Yoo, SangHyuk; Parale, Vinayak G.; Dhavale, Rushikesh P.; Kang, Keonwook; Sohn, Hyunchul; Park, Hyung-Ho
• Is Part Of: Applied materials today. Volume 28(2022)
• Publication Date: 2022-08
• Subjects: Aerogels -- Ultralow- κ -- Spin coating -- Cross-linked aerogel films -- Interlayer dielectric; Materials science -- Periodicals; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1016/j.apmt.2022.101536
• Languages: English
• ISSNs: 2352-9407

Abstract

Highlights: Silica aerogel thin film showed an ultralow dielectric constant of 1.7. Epoxide based linker enhanced the mechanical property of the silica aerogel films. Cross-linked aerogel films achieved the robust modulus over 5.1 GPa. Compatibility to semiconductor process were evaluated to demonstrate applicability. Abstract: An increase in resistance and capacitance (RC) delay has been a critical issue in reducing integrated circuit scales. The delay is successfully reduced using low dielectric constant (κ) interconnects and porous low-κ materials adopted in real devices. However, an increase in porosity could lower κ values with a dramatic decrease in elastic modulus, which would not sustain the stress during the packaging process. Highly porous cross-linked silica aerogel thin film with an ultralow-κ value of 1.7 applied to nanodevice interconnect technology has been suggested. Cross-linking using an epoxide ring-opening reaction produced a high elastic modulus (> 5.1 GPa), stable enough to sustain the chemical mechanical polishing (CMP) and the plasma dry etching process. The thickness of aerogel films is approximately 700 nm with a hydrophobic surface. Closed-surface pores created by selective solvent evaporation can prevent metal penetration. Our cross-linked aerogel films are the first among the low-dielectric aerogel films validated as interlayer low-dielectric materials and robust candidates for ultralow -κ dielectric materials. Graphical abstract: Image, graphical abstract