Evaluation for interface strength fluctuations induced by inhomogeneous grain structure of Cu line in LSI Interconnects

Chuantong Chen, Nobuyuki Shishido, Shoji Kamiya, Kozo Koiwa, Hisashi Sato, Masaki Omiya, Masahiro Nishida, Takashi Suzuki, Tomoji Nakamura, Takeshi Nokuo, Toshiaki Suzuki

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Local adhesion strength of the interface between Cu line and SiN cap layer in a Cu damascene interconnect structure of LSI has a significant fluctuation when evaluated with in-plane dimensions of 1 × 1 μm specimens, which was 4.78 ± 1.63 J/m2. The reproducibility of the evaluation technique was investigated by evaluating the strength of the Cu/SiN interface for the specimens fabricated on a plate of Cu single crystal, where the interface strength was measured as 0.62 ± 0.02 J/m2. The relative standard deviation of interface strength distribution in LSI interconnect structure was 34% which was more than ten times larger than the value 2.5% for the specimens fabricated on the plate of Cu single crystal. The significant fluctuation of interface strength was induced clearly not by the random error of the evaluation technique, but by the inhomogeneous grain structure of Cu line with various crystal orientations and grain boundaries. By means of elastic-plastic interface crack extension simulations, it was revealed that the difference in the amount of energy dissipated in plastic deformation of Cu layer mainly leads to a significant fluctuation of the apparent strength. Plastic deformation of Cu layer plays a dominant role on the local strength of interface Cu/SiN in LSI interconnects.

Original languageEnglish
Pages (from-to)52-58
Number of pages7
JournalMicroelectronic Engineering
Volume120
DOIs
Publication statusPublished - 2014 May 25

Fingerprint

large scale integration
Crystal microstructure
evaluation
Plastic deformation
Single crystals
Random errors
Bond strength (materials)
Crystal orientation
Grain boundaries
plastic deformation
Plastics
Cracks
random errors
single crystals
caps
standard deviation
adhesion
plastics
cracks
grain boundaries

Keywords

  • Cu single crystal
  • Elastic-plastic simulation
  • Local interface strength

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Electronic, Optical and Magnetic Materials
  • Surfaces, Coatings and Films
  • Atomic and Molecular Physics, and Optics
  • Condensed Matter Physics

Cite this

Evaluation for interface strength fluctuations induced by inhomogeneous grain structure of Cu line in LSI Interconnects. / Chen, Chuantong; Shishido, Nobuyuki; Kamiya, Shoji; Koiwa, Kozo; Sato, Hisashi; Omiya, Masaki; Nishida, Masahiro; Suzuki, Takashi; Nakamura, Tomoji; Nokuo, Takeshi; Suzuki, Toshiaki.

In: Microelectronic Engineering, Vol. 120, 25.05.2014, p. 52-58.

Research output: Contribution to journalArticle

Chen, C, Shishido, N, Kamiya, S, Koiwa, K, Sato, H, Omiya, M, Nishida, M, Suzuki, T, Nakamura, T, Nokuo, T & Suzuki, T 2014, 'Evaluation for interface strength fluctuations induced by inhomogeneous grain structure of Cu line in LSI Interconnects', Microelectronic Engineering, vol. 120, pp. 52-58. https://doi.org/10.1016/j.mee.2013.10.018
Chen, Chuantong ; Shishido, Nobuyuki ; Kamiya, Shoji ; Koiwa, Kozo ; Sato, Hisashi ; Omiya, Masaki ; Nishida, Masahiro ; Suzuki, Takashi ; Nakamura, Tomoji ; Nokuo, Takeshi ; Suzuki, Toshiaki. / Evaluation for interface strength fluctuations induced by inhomogeneous grain structure of Cu line in LSI Interconnects. In: Microelectronic Engineering. 2014 ; Vol. 120. pp. 52-58.
@article{3c9a3e0df0bb4a8ba3305313e49276b3,
title = "Evaluation for interface strength fluctuations induced by inhomogeneous grain structure of Cu line in LSI Interconnects",
abstract = "Local adhesion strength of the interface between Cu line and SiN cap layer in a Cu damascene interconnect structure of LSI has a significant fluctuation when evaluated with in-plane dimensions of 1 × 1 μm specimens, which was 4.78 ± 1.63 J/m2. The reproducibility of the evaluation technique was investigated by evaluating the strength of the Cu/SiN interface for the specimens fabricated on a plate of Cu single crystal, where the interface strength was measured as 0.62 ± 0.02 J/m2. The relative standard deviation of interface strength distribution in LSI interconnect structure was 34{\%} which was more than ten times larger than the value 2.5{\%} for the specimens fabricated on the plate of Cu single crystal. The significant fluctuation of interface strength was induced clearly not by the random error of the evaluation technique, but by the inhomogeneous grain structure of Cu line with various crystal orientations and grain boundaries. By means of elastic-plastic interface crack extension simulations, it was revealed that the difference in the amount of energy dissipated in plastic deformation of Cu layer mainly leads to a significant fluctuation of the apparent strength. Plastic deformation of Cu layer plays a dominant role on the local strength of interface Cu/SiN in LSI interconnects.",
keywords = "Cu single crystal, Elastic-plastic simulation, Local interface strength",
author = "Chuantong Chen and Nobuyuki Shishido and Shoji Kamiya and Kozo Koiwa and Hisashi Sato and Masaki Omiya and Masahiro Nishida and Takashi Suzuki and Tomoji Nakamura and Takeshi Nokuo and Toshiaki Suzuki",
year = "2014",
month = "5",
day = "25",
doi = "10.1016/j.mee.2013.10.018",
language = "English",
volume = "120",
pages = "52--58",
journal = "Microelectronic Engineering",
issn = "0167-9317",
publisher = "Elsevier",

}

TY - JOUR

T1 - Evaluation for interface strength fluctuations induced by inhomogeneous grain structure of Cu line in LSI Interconnects

AU - Chen, Chuantong

AU - Shishido, Nobuyuki

AU - Kamiya, Shoji

AU - Koiwa, Kozo

AU - Sato, Hisashi

AU - Omiya, Masaki

AU - Nishida, Masahiro

AU - Suzuki, Takashi

AU - Nakamura, Tomoji

AU - Nokuo, Takeshi

AU - Suzuki, Toshiaki

PY - 2014/5/25

Y1 - 2014/5/25

N2 - Local adhesion strength of the interface between Cu line and SiN cap layer in a Cu damascene interconnect structure of LSI has a significant fluctuation when evaluated with in-plane dimensions of 1 × 1 μm specimens, which was 4.78 ± 1.63 J/m2. The reproducibility of the evaluation technique was investigated by evaluating the strength of the Cu/SiN interface for the specimens fabricated on a plate of Cu single crystal, where the interface strength was measured as 0.62 ± 0.02 J/m2. The relative standard deviation of interface strength distribution in LSI interconnect structure was 34% which was more than ten times larger than the value 2.5% for the specimens fabricated on the plate of Cu single crystal. The significant fluctuation of interface strength was induced clearly not by the random error of the evaluation technique, but by the inhomogeneous grain structure of Cu line with various crystal orientations and grain boundaries. By means of elastic-plastic interface crack extension simulations, it was revealed that the difference in the amount of energy dissipated in plastic deformation of Cu layer mainly leads to a significant fluctuation of the apparent strength. Plastic deformation of Cu layer plays a dominant role on the local strength of interface Cu/SiN in LSI interconnects.

AB - Local adhesion strength of the interface between Cu line and SiN cap layer in a Cu damascene interconnect structure of LSI has a significant fluctuation when evaluated with in-plane dimensions of 1 × 1 μm specimens, which was 4.78 ± 1.63 J/m2. The reproducibility of the evaluation technique was investigated by evaluating the strength of the Cu/SiN interface for the specimens fabricated on a plate of Cu single crystal, where the interface strength was measured as 0.62 ± 0.02 J/m2. The relative standard deviation of interface strength distribution in LSI interconnect structure was 34% which was more than ten times larger than the value 2.5% for the specimens fabricated on the plate of Cu single crystal. The significant fluctuation of interface strength was induced clearly not by the random error of the evaluation technique, but by the inhomogeneous grain structure of Cu line with various crystal orientations and grain boundaries. By means of elastic-plastic interface crack extension simulations, it was revealed that the difference in the amount of energy dissipated in plastic deformation of Cu layer mainly leads to a significant fluctuation of the apparent strength. Plastic deformation of Cu layer plays a dominant role on the local strength of interface Cu/SiN in LSI interconnects.

KW - Cu single crystal

KW - Elastic-plastic simulation

KW - Local interface strength

UR - http://www.scopus.com/inward/record.url?scp=84898832903&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84898832903&partnerID=8YFLogxK

U2 - 10.1016/j.mee.2013.10.018

DO - 10.1016/j.mee.2013.10.018

M3 - Article

AN - SCOPUS:84898832903

VL - 120

SP - 52

EP - 58

JO - Microelectronic Engineering

JF - Microelectronic Engineering

SN - 0167-9317

ER -