Effect of Ti-capping thickness on the formation of an oxide-interlayer-mediated-epitaxial CoSi2 film by ex situ annealing

Gi Bum Kim, Joon Seop Kwak, Hong Koo Baik, Sung Man Lee

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

A modified oxide mediated epitaxy process using a single deposition and ex situ annealing by Ti capping has been suggested in this study. It has been shown that in the case of pure Co on SiOx-covered Si, the reaction between Co and Si did not occur up to 800 °C during ex situ annealing. However, Co silicidation occurred in the case of Ti-capped Co on SiOx.-covered Si. The crystalline nature of CoSi2 formed in this case strongly depends on the Ti capping thickness. When a thin Ti capping layer of thickness less than 5 nm was used, Ti oxidation occurred nonuniformly, and the morphology of the surface Ti oxide layer was very rough. This caused an exposure of Co to the oxygen in the ambient, resulting in the formation of polycrystalline CoSi2 due to the suppressed Co diffusion towards the Si substrate. In the case of Ti capping thickness being more than 10 nm, however, a uniform Ti oxide surface layer, which blocks the incoming oxygen retarding Co diffusion, was formed, and it led to uniform Co diffusion into the Si substrate, resulting in epitaxial CoSi2.

Original languageEnglish
Pages (from-to)1503-1507
Number of pages5
JournalJournal of Applied Physics
Volume85
Issue number3
DOIs
Publication statusPublished - 1999 Jan 1

Fingerprint

interlayers
annealing
oxides
oxygen
epitaxy
surface layers
retarding
oxidation

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Cite this

@article{13a0950d6769487fb06939f7ca2a9989,
title = "Effect of Ti-capping thickness on the formation of an oxide-interlayer-mediated-epitaxial CoSi2 film by ex situ annealing",
abstract = "A modified oxide mediated epitaxy process using a single deposition and ex situ annealing by Ti capping has been suggested in this study. It has been shown that in the case of pure Co on SiOx-covered Si, the reaction between Co and Si did not occur up to 800 °C during ex situ annealing. However, Co silicidation occurred in the case of Ti-capped Co on SiOx.-covered Si. The crystalline nature of CoSi2 formed in this case strongly depends on the Ti capping thickness. When a thin Ti capping layer of thickness less than 5 nm was used, Ti oxidation occurred nonuniformly, and the morphology of the surface Ti oxide layer was very rough. This caused an exposure of Co to the oxygen in the ambient, resulting in the formation of polycrystalline CoSi2 due to the suppressed Co diffusion towards the Si substrate. In the case of Ti capping thickness being more than 10 nm, however, a uniform Ti oxide surface layer, which blocks the incoming oxygen retarding Co diffusion, was formed, and it led to uniform Co diffusion into the Si substrate, resulting in epitaxial CoSi2.",
author = "Kim, {Gi Bum} and Kwak, {Joon Seop} and Baik, {Hong Koo} and Lee, {Sung Man}",
year = "1999",
month = "1",
day = "1",
doi = "10.1063/1.369843",
language = "English",
volume = "85",
pages = "1503--1507",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics Publising LLC",
number = "3",

}

Effect of Ti-capping thickness on the formation of an oxide-interlayer-mediated-epitaxial CoSi2 film by ex situ annealing. / Kim, Gi Bum; Kwak, Joon Seop; Baik, Hong Koo; Lee, Sung Man.

In: Journal of Applied Physics, Vol. 85, No. 3, 01.01.1999, p. 1503-1507.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Effect of Ti-capping thickness on the formation of an oxide-interlayer-mediated-epitaxial CoSi2 film by ex situ annealing

AU - Kim, Gi Bum

AU - Kwak, Joon Seop

AU - Baik, Hong Koo

AU - Lee, Sung Man

PY - 1999/1/1

Y1 - 1999/1/1

N2 - A modified oxide mediated epitaxy process using a single deposition and ex situ annealing by Ti capping has been suggested in this study. It has been shown that in the case of pure Co on SiOx-covered Si, the reaction between Co and Si did not occur up to 800 °C during ex situ annealing. However, Co silicidation occurred in the case of Ti-capped Co on SiOx.-covered Si. The crystalline nature of CoSi2 formed in this case strongly depends on the Ti capping thickness. When a thin Ti capping layer of thickness less than 5 nm was used, Ti oxidation occurred nonuniformly, and the morphology of the surface Ti oxide layer was very rough. This caused an exposure of Co to the oxygen in the ambient, resulting in the formation of polycrystalline CoSi2 due to the suppressed Co diffusion towards the Si substrate. In the case of Ti capping thickness being more than 10 nm, however, a uniform Ti oxide surface layer, which blocks the incoming oxygen retarding Co diffusion, was formed, and it led to uniform Co diffusion into the Si substrate, resulting in epitaxial CoSi2.

AB - A modified oxide mediated epitaxy process using a single deposition and ex situ annealing by Ti capping has been suggested in this study. It has been shown that in the case of pure Co on SiOx-covered Si, the reaction between Co and Si did not occur up to 800 °C during ex situ annealing. However, Co silicidation occurred in the case of Ti-capped Co on SiOx.-covered Si. The crystalline nature of CoSi2 formed in this case strongly depends on the Ti capping thickness. When a thin Ti capping layer of thickness less than 5 nm was used, Ti oxidation occurred nonuniformly, and the morphology of the surface Ti oxide layer was very rough. This caused an exposure of Co to the oxygen in the ambient, resulting in the formation of polycrystalline CoSi2 due to the suppressed Co diffusion towards the Si substrate. In the case of Ti capping thickness being more than 10 nm, however, a uniform Ti oxide surface layer, which blocks the incoming oxygen retarding Co diffusion, was formed, and it led to uniform Co diffusion into the Si substrate, resulting in epitaxial CoSi2.

UR - http://www.scopus.com/inward/record.url?scp=0000795526&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000795526&partnerID=8YFLogxK

U2 - 10.1063/1.369843

DO - 10.1063/1.369843

M3 - Article

AN - SCOPUS:0000795526

VL - 85

SP - 1503

EP - 1507

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

IS - 3

ER -