Share Email Print

Proceedings Paper • new

Formation of nanoporous SiO2 films with super-low dielectric constant by F2 laser deposition
Author(s): Ryota Miyano; Toshifumi Kikuchi; Kaname Imokawa; Daisuke Nakamura; Hiroshi Ikenoue
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Ultra-large scale integrated circuits (ULSIs) have been continually scaled down according to Moore’s law. This can improve their power consumption and operation frequency but not the RC delay of their interconnections; to this end, super low dielectric constant films are required. We propose a novel method to fabricate porous SiO2 films with a super low dielectric constant by F2 laser deposition. In this method, a quartz target is evaporated by F2 laser ablation in vacuum-chamber-controlled Ar partial pressure. The evaporated SiO2 molecules are agglomerated in the vacuum, and the size of the SiO2 nanoparticles are controlled by the Ar partial pressure. Porous SiO2 films are formed on a Si-receiving substrate, which is placed in front of the quartz target. The pulse duration of the F2 laser was approximately 20 ns, and the repetition rate of laser shots was 100 Hz. The base pressure of the vacuum chamber was 5 × 10−3 Pa. Then, Ar gas was introduced into the vacuum chamber through a mass flow controller to control the Ar partial pressure. The dominant size of the SiO2 nanoparticles decreased from 1.5–2.0 nm to 1.0–1.5 nm with the Ar partial pressure decreasing from 20 Pa to 4.5 Pa. In addition, the relative dielectric constant k of the porous SiO2 film formed at an Ar partial pressure of 4.5 Pa was 2.8, which is lower than that of thermal SiO2 (k = 4.0). In addition, the leakage current of the nanoporous SiO2 film was almost equal to that of the thermal SiO2 film. From these results, we conclude that nanoporous SiO2 films with a super low dielectric constant can be formed by F2 laser deposition.

Paper Details

Date Published: 4 March 2019
PDF: 6 pages
Proc. SPIE 10907, Synthesis and Photonics of Nanoscale Materials XVI, 109070S (4 March 2019); doi: 10.1117/12.2509176
Show Author Affiliations
Ryota Miyano, Kyushu Univ. (Japan)
Toshifumi Kikuchi, Kyushu Univ. (Japan)
Kaname Imokawa, Kyushu Univ. (Japan)
Daisuke Nakamura, Kyushu Univ. (Japan)
Hiroshi Ikenoue, Kyushu Univ. (Japan)

Published in SPIE Proceedings Vol. 10907:
Synthesis and Photonics of Nanoscale Materials XVI
Andrei V. Kabashin; Jan J. Dubowski; David B. Geohegan, Editor(s)

© SPIE. Terms of Use
Back to Top