Two-Step Plasma Treatment on Sputtered and Electroplated Cu Surfaces for Cu-To-Cu Bonding Application

The technology trends of next generation electronic packaging are moving toward heterogeneous 3D packaging systems. One of the key processes of 3D packaging system is Cu-to-Cu bonding, which is highly dependent on the planarized, activated, and oxygen-free Cu surface. A two-step plasma treatment is studied to form a Cu surface that does not react with oxygen and improves the Cu bonding interface quality at low bonding temperature (300 °C). In this study, the effects of two-step plasma treatment on both sputtered and electroplated Cu surfaces were evaluated through structural, chemical, and electrical analysis. The Cu bonding interface was studied by scanning acoustic tomography analysis after the thermocompression bonding process. Both sputtered and electroplated Cu thin films had the preferred orientation of (111) plane, but sputtered Cu exhibited larger grains than the electroplated Cu. As a result, the roughness of sputtered Cu was lower, and the resistivity was higher than that of electroplated Cu. Based on X-ray photoelectron spectroscopy analysis, the sputtered Cu formed more copper nitrides and fewer copper oxides than the electroplated Cu. A significant improvement in bonding quality at the Cu bonded interface was observed in sputtered Cu.

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Low Temperature Direct Metal Bonding by Self Assembled Monolayers

MRS Proceedings ◽

10.1557/proc-0990-b10-03 ◽

2007 ◽

Vol 990 ◽

Author(s):

Xiaofang Ang ◽

Li Cheong Chin ◽

Guo Ge Zhang ◽

Jun Wei ◽

Zhong Chen ◽

...

Keyword(s):

Low Temperature ◽

Photoelectron Spectroscopy ◽

Self Assembly ◽

Surface Passivation ◽

Bonding Temperature ◽

Gold Surface ◽

Self Assembled Monolayers ◽

Assembled Monolayers ◽

Thermocompression Bonding ◽

Self Assembled

ABSTRACTElevated bonding temperature for interconnection deteriorates the reliability of both the device and the interconnect; hence the imperative for developing low temperature bonding methods. This study investigates the feasibility of using self-assembled monolayers (SAMs) to assist direct gold-gold bonding. This involves a simple molecular self-assembly process whereby a monolayer of alkyl chains with a sulfur end group is attached to the gold surface prior to thermocompression bonding. Using this method, we have achieved gold to gold bonding at a bonding temperature below 100°C, a significant reduction compared to the conventional bonding temperatures of above 150 °C. We attribute this temperature reduction to two properties of SAMs - (1) surface passivation of the Au surface that precludes adsorption of surface contaminants, and (2) The easy displacement of SAMs through thermal desorption just before bonding occurs. This SAMs-assisted bonding mechanism is supported by X-ray photoelectron spectroscopy (XPS) and surface plasmon resonance (SPR) results.

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X-ray photoelectron spectroscopy analysis on surface modification of Konjac glucomannan membrane by nitrogen plasma treatment

Carbohydrate Polymers ◽

10.1016/j.carbpol.2011.12.013 ◽

2012 ◽

Vol 88 (1) ◽

pp. 369-372 ◽

Cited By ~ 14

Author(s):

Jie Pang ◽

Wenjie Jian ◽

Liangyu Wang ◽

Chunhua Wu ◽

Yanan Liu ◽

...

Keyword(s):

Surface Modification ◽

Plasma Treatment ◽

Photoelectron Spectroscopy ◽

Nitrogen Plasma ◽

Konjac Glucomannan ◽

Spectroscopy Analysis ◽

X Ray

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Non-Thermal Plasma-Modified Ru-Sn-Ti Catalyst for Chlorinated Volatile Organic Compound Degradation

Catalysts ◽

10.3390/catal10121456 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1456

Author(s):

Yujie Fu ◽

You Zhang ◽

Qi Xin ◽

Zhong Zheng ◽

Yu Zhang ◽

...

Keyword(s):

Plasma Treatment ◽

Photoelectron Spectroscopy ◽

High Surface ◽

High Surface Area ◽

Surface Oxidation ◽

Treatment Method ◽

X Ray ◽

Chlorinated Volatile Organic Compounds ◽

Volatile Organic ◽

Doped Titania

Chlorinated volatile organic compounds (CVOCs) are vital environmental concerns due to their low biodegradability and long-term persistence. Catalytic combustion technology is one of the more commonly used technologies for the treatment of CVOCs. Catalysts with high low-temperature activity, superior selectivity of non-toxic products, and resistance to chlorine poisoning are desirable. Here we adopted a plasma treatment method to synthesize a tin-doped titania loaded with ruthenium dioxide (RuO2) catalyst, possessing enhanced activity (T90%, the temperature at which 90% of dichloromethane (DCM) is decomposed, is 262 °C) compared to the catalyst prepared by the conventional calcination method. As revealed by transmission electron microscopy, X-ray diffraction, N2 adsorption, X-ray photoelectron spectroscopy, and hydrogen temperature-programmed reduction, the high surface area of the tin-doped titania catalyst and the enhanced dispersion and surface oxidation of RuO2 induced by plasma treatment were found to be the main factors determining excellent catalytic activities.

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X-Ray Photoelectron-Spectroscopic Studies of Carbon Fiber Surfaces. Part IX: The Effect of Microwave Plasma Treatment on Carbon Fiber Surfaces

Applied Spectroscopy ◽

10.1366/0003702894203543 ◽

1989 ◽

Vol 43 (7) ◽

pp. 1153-1158 ◽

Cited By ~ 59

Author(s):

Yaoming Xie ◽

Peter M. A. Sherwood

Keyword(s):

Carbon Fiber ◽

Plasma Treatment ◽

Photoelectron Spectroscopy ◽

Prolonged Exposure ◽

Microwave Plasma ◽

Spectroscopic Studies ◽

X Ray ◽

Fiber Damage ◽

Surface Functionality ◽

Fiber Treatment

X-ray photoelectron spectroscopy has been used to monitor the surface chemical changes occurring on type II carbon fibers exposed to air, oxygen, and nitrogen plasmas. In all cases the plasmas caused changes in surface functionality, in terms of both C-O and C-N functionality. Prolonged exposure to the plasmas caused loss of surface functionality for air and oxygen plasmas, and extended treatment caused fiber damage. Plasma treatment of fibers promises to be an effective method of fiber treatment.

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X‐ray photoelectron spectroscopy analysis of photostimulated chemical vapor deposition hydrogenated amorphous silicon/amorphous aluminum oxide

Applied Physics Letters ◽

10.1063/1.107407 ◽

1992 ◽

Vol 60 (10) ◽

pp. 1208-1210 ◽

Cited By ~ 1

Author(s):

K. Uwasawa ◽

F. Ishihara ◽

S. Matsumoto

Keyword(s):

Chemical Vapor Deposition ◽

Aluminum Oxide ◽

Amorphous Silicon ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Hydrogenated Amorphous Silicon ◽

Chemical Vapor ◽

Spectroscopy Analysis ◽

X Ray ◽

Hydrogenated Amorphous

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X-ray photoelectron spectroscopy and positron annihilation spectroscopy analysis of surfactant affected FePt spintronic films

Applied Surface Science ◽

10.1016/j.apsusc.2014.04.190 ◽

2014 ◽

Vol 308 ◽

pp. 408-413 ◽

Cited By ~ 1

Author(s):

Chun Feng ◽

Xujing Li ◽

Fen Liu ◽

Qiang Wang ◽

Meiyin Yang ◽

...

Keyword(s):

Positron Annihilation ◽

Photoelectron Spectroscopy ◽

Positron Annihilation Spectroscopy ◽

Spectroscopy Analysis ◽

X Ray

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SiO2 films as heat resistant layers for protection of expandable polystyrene foam from flame torch–induced heat

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717718238 ◽

2017 ◽

Vol 31 (5) ◽

pp. 657-667 ◽

Cited By ~ 1

Author(s):

S Varnagiris ◽

S Tuckute ◽

M Lelis ◽

D Milcius

Keyword(s):

Heat Resistance ◽

Photoelectron Spectroscopy ◽

Silicon Oxide ◽

Plasma Generator ◽

Expanded Polystyrene ◽

Spectroscopy Analysis ◽

X Ray ◽

Heat Resistant ◽

Pulsed Dc ◽

Gas Atmosphere

Currently, polymeric insulation materials are widely used for energy saving in buildings. Despite of all benefits, these materials are generally sensitive to heat and highly flammable. This work discusses possibility to improve heat resistance of expanded polystyrene (EPS) foam using thin silicon dioxide (SiO2) films deposited by magnetron sputtering technique. In order to increase surface energy and adherence of SiO2 thin films to substrate EPS was plasma pretreated before films’ depositions using pulsed DC plasma generator for 40 s in argon gas. SiO2 formation was done in reactive argon and oxygen gas atmosphere. Laboratory made equipment was used for flame torch–induced heat resistance experiments. Results showed that silicon oxide films remains stable during heat resistance experiments up to 5 s and fully protects polystyrene (PS) substrate. Films are relatively stable for 30 s and 60 s and partially protect PS from melting and ignition. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy analysis confirmed that SiO2 layer, which is distributed uniformly on the EPS surface, could work as a good heat resistant material.

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Effect of Sodium Metabisulfite on Selective Flotation of Chalcopyrite and Molybdenite

Minerals ◽

10.3390/min11121377 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1377

Author(s):

Yuki Semoto ◽

Gde Pandhe Wisnu Suyantara ◽

Hajime Miki ◽

Keiko Sasaki ◽

Tsuyoshi Hirajima ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Separation Efficiency ◽

Diesel Oil ◽

Sodium Metabisulfite ◽

Depressing Effect ◽

Spectroscopy Analysis ◽

X Ray ◽

Selective Flotation

Sodium metabisulfite (MBS) was used in this study for selective flotation of chalcopyrite and molybdenite. Microflotation tests of single and mixed minerals were performed to assess the floatability of chalcopyrite and molybdenite. The results of microflotation of single minerals showed that MBS treatment significantly depressed the floatability of chalcopyrite and slightly reduced the floatability of molybdenite. The results of microflotation of mixed minerals demonstrated that the MBS treatment could be used as a selective chalcopyrite depressant in the selective flotation of chalcopyrite and molybdenite. Furthermore, the addition of diesel oil or kerosene could significantly improve the separation efficiency of selective flotation of chalcopyrite and molybdenite using MBS treatment. A mechanism based on X-ray photoelectron spectroscopy analysis results is proposed in this study to explain the selective depressing effect of MBS on the flotation of chalcopyrite and molybdenite.

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