Effects of excimer irradiation treatment on thermocompression Au-Au bonding

Naoko Unami, Katsuyuki Sakuma, Jun Mizuno, Shuichi Shoji

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

We studied the feasibility of using vacuum ultraviolet (VUV) treatment as a surface improvement technique with Au-Au flip-chip bonding. For finepitch electrical interconnections in three-dimensional (3D) stack applications, robust and reliable bonding is desirable; in this case, surface modification treatment is needed before the bonding process. A VUV surface treatment was used to remove organic contaminants. Samples of electroplated Au pads were examined by X-ray photoelectron spectroscopy (XPS) to evaluate the chemical composition of the Au surfaces. The XPS results revealed that the carbon-based contaminants on the surface were removed by the VUV treatment. The shear strength of the bonded sample was also improved. The average shear strength of a bump with VUV treatment is 1.6 times larger than that of a bump without VUV treatment. Cross-sectional scanning electron microscopy (SEM) images of the bonded samples confirmed the absence of voids and cracks. The results show that VUV treatment has clear effects on Au-Au flip-chip bonding.

Original languageEnglish
JournalJapanese Journal of Applied Physics
Volume49
Issue number6 PART 2
DOIs
Publication statusPublished - 2010 Jun

Fingerprint

excimers
Irradiation
Vacuum
vacuum
irradiation
shear strength
Shear strength
contaminants
Surface treatment
X ray photoelectron spectroscopy
chips
photoelectron spectroscopy
Impurities
surface treatment
voids
chemical composition
x rays
cracks
Cracks
Scanning electron microscopy

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

Cite this

Effects of excimer irradiation treatment on thermocompression Au-Au bonding. / Unami, Naoko; Sakuma, Katsuyuki; Mizuno, Jun; Shoji, Shuichi.

In: Japanese Journal of Applied Physics, Vol. 49, No. 6 PART 2, 06.2010.

Research output: Contribution to journalArticle

@article{648c050088d546848edfeffbf2bba4c0,
title = "Effects of excimer irradiation treatment on thermocompression Au-Au bonding",
abstract = "We studied the feasibility of using vacuum ultraviolet (VUV) treatment as a surface improvement technique with Au-Au flip-chip bonding. For finepitch electrical interconnections in three-dimensional (3D) stack applications, robust and reliable bonding is desirable; in this case, surface modification treatment is needed before the bonding process. A VUV surface treatment was used to remove organic contaminants. Samples of electroplated Au pads were examined by X-ray photoelectron spectroscopy (XPS) to evaluate the chemical composition of the Au surfaces. The XPS results revealed that the carbon-based contaminants on the surface were removed by the VUV treatment. The shear strength of the bonded sample was also improved. The average shear strength of a bump with VUV treatment is 1.6 times larger than that of a bump without VUV treatment. Cross-sectional scanning electron microscopy (SEM) images of the bonded samples confirmed the absence of voids and cracks. The results show that VUV treatment has clear effects on Au-Au flip-chip bonding.",
author = "Naoko Unami and Katsuyuki Sakuma and Jun Mizuno and Shuichi Shoji",
year = "2010",
month = "6",
doi = "10.1143/JJAP.49.06GN12",
language = "English",
volume = "49",
journal = "Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes",
issn = "0021-4922",
publisher = "Japan Society of Applied Physics",
number = "6 PART 2",

}

TY - JOUR

T1 - Effects of excimer irradiation treatment on thermocompression Au-Au bonding

AU - Unami, Naoko

AU - Sakuma, Katsuyuki

AU - Mizuno, Jun

AU - Shoji, Shuichi

PY - 2010/6

Y1 - 2010/6

N2 - We studied the feasibility of using vacuum ultraviolet (VUV) treatment as a surface improvement technique with Au-Au flip-chip bonding. For finepitch electrical interconnections in three-dimensional (3D) stack applications, robust and reliable bonding is desirable; in this case, surface modification treatment is needed before the bonding process. A VUV surface treatment was used to remove organic contaminants. Samples of electroplated Au pads were examined by X-ray photoelectron spectroscopy (XPS) to evaluate the chemical composition of the Au surfaces. The XPS results revealed that the carbon-based contaminants on the surface were removed by the VUV treatment. The shear strength of the bonded sample was also improved. The average shear strength of a bump with VUV treatment is 1.6 times larger than that of a bump without VUV treatment. Cross-sectional scanning electron microscopy (SEM) images of the bonded samples confirmed the absence of voids and cracks. The results show that VUV treatment has clear effects on Au-Au flip-chip bonding.

AB - We studied the feasibility of using vacuum ultraviolet (VUV) treatment as a surface improvement technique with Au-Au flip-chip bonding. For finepitch electrical interconnections in three-dimensional (3D) stack applications, robust and reliable bonding is desirable; in this case, surface modification treatment is needed before the bonding process. A VUV surface treatment was used to remove organic contaminants. Samples of electroplated Au pads were examined by X-ray photoelectron spectroscopy (XPS) to evaluate the chemical composition of the Au surfaces. The XPS results revealed that the carbon-based contaminants on the surface were removed by the VUV treatment. The shear strength of the bonded sample was also improved. The average shear strength of a bump with VUV treatment is 1.6 times larger than that of a bump without VUV treatment. Cross-sectional scanning electron microscopy (SEM) images of the bonded samples confirmed the absence of voids and cracks. The results show that VUV treatment has clear effects on Au-Au flip-chip bonding.

UR - http://www.scopus.com/inward/record.url?scp=77955341669&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77955341669&partnerID=8YFLogxK

U2 - 10.1143/JJAP.49.06GN12

DO - 10.1143/JJAP.49.06GN12

M3 - Article

VL - 49

JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

SN - 0021-4922

IS - 6 PART 2

ER -