AVS 53rd International Symposium
    Nanometer-scale Science and Technology Thursday Sessions
       Session NS-ThA

Paper NS-ThA6
Fabrication of Thin Silicon Nanodisk for Quantum Effect Devices Using Cl Neutral Beam Etching and Ferritin Iron Core Mask

Thursday, November 16, 2006, 3:40 pm, Room 2016

Session: Nanoscale Material Processing
Presenter: T. Kubota, Tohoku University, Japan
Authors: T. Kubota, Tohoku University, Japan
T. Hashimoto, Tohoku University, Japan
M. Takeguchi, National Institute for Materials Science, Japan
Y. Uraoka, Nara Institute of Science and Technology, Japan
T. Fuyuki, Nara Institute of Science and Technology, Japan
I. Yamashita, Matsushita Electric Industrial Co., Ltd. and Nara Institute of Science and Technology, Japan
S. Samukawa, Tohoku University, Japan
Correspondent: Click to Email
Miniaturization of semiconductor devices will require new fabrication processes to realize nanometer-scale structures without process damages. To realize a nanometer-scale structure, we used ferritin iron core (7nm in diameter) as a uniform and high-density template, and our developed neutral beam (NB) etching process for damage-free etching. We have fabricated "nanodisk", a nanometer-thick disk-shaped silicon structure. Thin oxide layer of about 1nm was grown on Si(100) wafer and then 4-nm-thick Si layer was deposited. The Si layer was etched by using Cl NB with ferritin iron core as an etching mask. There were two problems which had to be solved to fabricate thin nanodisk. (1) The native oxide layer on thin Si layer causes enlarging the diameter of nanodisk. (2) The oxide layer must be remained while Si layer has to be completely etched. To solve these problems, two step NB etching process was performed. High-energy neutral beam was used for the first step to breakthrough the native oxide and low-energy neutral beam was used for the second step to obtain high etching selectivity to underlying-SiO@sub 2@. To monitor the proceeding of atomic layer etching, XPS measurement was utilized. We could successfully observe the fabrication of silicon nanodisk (2nm in thick and 10nm in diameter) through cross-sectional TEM. Such nanometer-scale structure would be applied to quantum effect devices. A part of this work was supported by "Nanotechnology Support Project" of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. This study was supported by Leading Project of Ministry of Education, Culture, Sports, Science and Technology.