Formation of vertically aligned cobalt Silicide Nanowire arrays through a solid-state reaction

Seulah Lee, Jaehong Yoon, Bonwoong Koo, Dong Hoon Shin, Ja Hoon Koo, Cheol Jin Lee, Young Woon Kim, Hyungjun Kim, Taeyoon Lee

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)

Abstract

We report for the first time synthesis of high-density arrays of vertically well-aligned cobalt monosilicide (CoSi) nanowires (NWs) in a large area via a solid-state reaction. The vertical arrays of 1-μm-long Si NWs were first grown on a p-type (1 0 0) Si substrate by the aqueous electroless etching (AEE) method, and a 40-nm-thick Co layer was conformally deposited using a thermal atomic layer deposition system as revealed by SEM and transmission electron microscope analyses. The rapid thermal annealing process was carried out at various temperatures ranging from 700 to 1000 °C; the X-ray diffraction analysis confirmed that the polycrystalline CoSi NW arrays were formed at temperatures above 900 °C. The required high driving force for this silicide formation can be attributed to the significant amounts of oxygen-related contaminants at the defect sites of the highly rough surfaces of AEE-grown Si NWs. To demonstrate practical applications, field emitters and Schottky diodes were fabricated using the vertically aligned CoSi NW arrays. The field emission measurements showed a turn-on field of 10.9 V/μm and a field enhancement factor of 328, indicating the feasibility of vertically aligned CoSi NW arrays as promising field emitters. For the Schottky diodes, the measured Schottky barrier height was 0.52 eV and the estimated ideality factor obtained from the I-V characteristic curves was 2.28.

Original languageEnglish
Article number6542738
Pages (from-to)704-711
Number of pages8
JournalIEEE Transactions on Nanotechnology
Volume12
Issue number5
DOIs
Publication statusPublished - 2013

Keywords

  • Atomic layer deposition (ALD)
  • Schottky diode
  • cobalt silicide nanowire
  • field emission
  • rapid thermal annealing (RTA)
  • solid-state reaction

ASJC Scopus subject areas

  • Computer Science Applications
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Formation of vertically aligned cobalt Silicide Nanowire arrays through a solid-state reaction'. Together they form a unique fingerprint.

Cite this