Evaluation of electroless deposited Co(W,P) thin films as diffusion barriers for copper metallization

A. Kohn; M. Eizenberg; Y. Shacham-Diamand; B. Israel; Y. Sverdlov

doi:10.1016/S0167-9317(00)00460-3

Evaluation of electroless deposited Co(W,P) thin films as diffusion barriers for copper metallization

A. Kohn^*, M. Eizenberg, Y. Shacham-Diamand, B. Israel, Y. Sverdlov

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

65 Scopus citations

Abstract

Electroless deposited Co(W,P) thin films were evaluated as diffusion barriers for copper metallization. Capacitance versus time measurements of MOS structures as well as SIMS depth profiles indicate that 30-nm-thick films can function as effective barriers against copper diffusion after thermal treatments up to 500 °C. The improved barrier properties relative to sputtered cobalt are explained by the incorporation of phosphorus (8-10 at.%) and tungsten (approximately 2 at.%) which most probably enrich the grain boundaries of the nanocrystalline hcp cobalt grains, forming a `stuffed' barrier. The phosphorus and tungsten additions stabilize the hcp crystalline structure of the cobalt grains, delaying the transition to the fcc phase by more than 80 °C compared to bulk pure cobalt. An advantage of this material compared to alternative diffusion barriers for copper is its relatively low resistivity of 80 μΩ cm.

Original language	English
Pages (from-to)	297-303
Number of pages	7
Journal	Microelectronic Engineering
Volume	55
Issue number	1-4
DOIs	https://doi.org/10.1016/S0167-9317(00)00460-3
State	Published - Mar 2001
Externally published	Yes

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@article{a55b7008bf1547aaae03ec174782d793,

title = "Evaluation of electroless deposited Co(W,P) thin films as diffusion barriers for copper metallization",

abstract = "Electroless deposited Co(W,P) thin films were evaluated as diffusion barriers for copper metallization. Capacitance versus time measurements of MOS structures as well as SIMS depth profiles indicate that 30-nm-thick films can function as effective barriers against copper diffusion after thermal treatments up to 500 °C. The improved barrier properties relative to sputtered cobalt are explained by the incorporation of phosphorus (8-10 at.%) and tungsten (approximately 2 at.%) which most probably enrich the grain boundaries of the nanocrystalline hcp cobalt grains, forming a `stuffed' barrier. The phosphorus and tungsten additions stabilize the hcp crystalline structure of the cobalt grains, delaying the transition to the fcc phase by more than 80 °C compared to bulk pure cobalt. An advantage of this material compared to alternative diffusion barriers for copper is its relatively low resistivity of 80 μΩ cm.",

author = "A. Kohn and M. Eizenberg and Y. Shacham-Diamand and B. Israel and Y. Sverdlov",

note = "Funding Information: The work was supported by grant no. 8460-1-98 from the Israel Ministry of Science and Technology. The assistance of R. Brener, C. Cytermann and R. Kroeger is gratefully acknowledged. ",

year = "2001",

month = mar,

doi = "10.1016/S0167-9317(00)00460-3",

language = "英语",

volume = "55",

pages = "297--303",

journal = "Microelectronic Engineering",

issn = "0167-9317",

publisher = "Elsevier",

number = "1-4",

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TY - JOUR

T1 - Evaluation of electroless deposited Co(W,P) thin films as diffusion barriers for copper metallization

AU - Kohn, A.

AU - Eizenberg, M.

AU - Shacham-Diamand, Y.

AU - Israel, B.

AU - Sverdlov, Y.

N1 - Funding Information: The work was supported by grant no. 8460-1-98 from the Israel Ministry of Science and Technology. The assistance of R. Brener, C. Cytermann and R. Kroeger is gratefully acknowledged.

PY - 2001/3

Y1 - 2001/3

N2 - Electroless deposited Co(W,P) thin films were evaluated as diffusion barriers for copper metallization. Capacitance versus time measurements of MOS structures as well as SIMS depth profiles indicate that 30-nm-thick films can function as effective barriers against copper diffusion after thermal treatments up to 500 °C. The improved barrier properties relative to sputtered cobalt are explained by the incorporation of phosphorus (8-10 at.%) and tungsten (approximately 2 at.%) which most probably enrich the grain boundaries of the nanocrystalline hcp cobalt grains, forming a `stuffed' barrier. The phosphorus and tungsten additions stabilize the hcp crystalline structure of the cobalt grains, delaying the transition to the fcc phase by more than 80 °C compared to bulk pure cobalt. An advantage of this material compared to alternative diffusion barriers for copper is its relatively low resistivity of 80 μΩ cm.

AB - Electroless deposited Co(W,P) thin films were evaluated as diffusion barriers for copper metallization. Capacitance versus time measurements of MOS structures as well as SIMS depth profiles indicate that 30-nm-thick films can function as effective barriers against copper diffusion after thermal treatments up to 500 °C. The improved barrier properties relative to sputtered cobalt are explained by the incorporation of phosphorus (8-10 at.%) and tungsten (approximately 2 at.%) which most probably enrich the grain boundaries of the nanocrystalline hcp cobalt grains, forming a `stuffed' barrier. The phosphorus and tungsten additions stabilize the hcp crystalline structure of the cobalt grains, delaying the transition to the fcc phase by more than 80 °C compared to bulk pure cobalt. An advantage of this material compared to alternative diffusion barriers for copper is its relatively low resistivity of 80 μΩ cm.

UR - http://www.scopus.com/inward/record.url?scp=0034830082&partnerID=8YFLogxK

U2 - 10.1016/S0167-9317(00)00460-3

DO - 10.1016/S0167-9317(00)00460-3

M3 - 文章

AN - SCOPUS:0034830082

SN - 0167-9317

VL - 55

SP - 297

EP - 303

JO - Microelectronic Engineering

JF - Microelectronic Engineering

IS - 1-4

ER -

Evaluation of electroless deposited Co(W,P) thin films as diffusion barriers for copper metallization

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