Enhanced adhesion of copper to dielectrics via titanium and chromium additions and sacrificial reactions

Low load multiple scratch tests of ceramics and hard metals

Effects of annealing and interlayers on the adhesion energy of copper thin films to SiO2/Si substrates

Constitutive flow behavior and hot workability of the powder metallurgy processed 20 vol.%SiC(P)/2024Al composite were investigated using hot compression tests. The modified Arrhenius-type constitutive equations were presented with the values of material constants in consideration as a function of strain. Dynamic material model (DMM) and modified DMM were used to construct the power dissipation efficiency maps, and Ziegler's instability criterion and Gegel's stability criterion were used to build instability maps. The presence of finer SiC(P) and more boundaries resulting from smaller 2024Al powders shifted the dynamic recrystallization domain of the 2024Al matrix to higher strain rate and lower temperature ranges and decreased the peak value of power dissipation efficiency. Large instable regions were found in the form of flow localization and cavitations located at the matrix/SiC(P) interfaces and within the SiC(P) clusters. By comparison, the Gegel's stability criterion was more sensitive to the instability zones than the Ziegler's instability criterion for this material. (c) 2010 Elsevier B.V. All rights reserved.

Constitutive flow behavior and hot workability of powder metallurgy processed 20 vol.%SiCP/2024Al composite

Study on hot deformation behavior and workability of squeeze-cast 20 vol%SiCw/6061Al composites using processing map

Ion-beam mixing in Al-Pd, Al-Cr, Pd-Cu, Ag-Cu and Ag-Fe bilayers has been studied using Rutherford backscattering spectroscopy (RBS) and Auger electron spectroscopy (AES) over an ion dose range between 1 × 1015 and 1 × 1016 Ar+ cm−2 at room temperature. RBS and AES results show that the mixing efficiency of the light elements is higher than that of the heavy elements. The mixing efficiency of a heavy element is independent of the heat of mixing energy, while that of a light element has a close relation with the heat of mixing. The experimental results are discussed in terms of cascade mixing and thermal spike mixing.

Ar+-induced mixing mechanisms in metal-metal bilayer systems

A thin copper layer (35 nm) deposited on SiO2 has been subjected to ion-beam mixing with 80 keV Ar+ at room temperature, 550 and 650 K. Interfacial properties of irradiated samples were investigated using Rutherford backscattering spectroscopy, grazing-angle X-ray diffraction, X-ray photo-electron spectroscopy and scratch testing. The adhesion of the copper film was improved by a factor of three at a dose of 1.5 × 1016 Ar+ cm−2 by the ion-beam mixing at room temperature, while the high-temperature ion-beam mixing enhanced the adhesion by a factor of five. Ballistic mixing plays a role in the improvement of adhesion for the room-temperature ion mixing, and the creation of Cu2O phase induced by ion-beam mixing contributes to the enhancement of adhesion at high temperature.

H. G. Jang

Papers

Ar+-induced mixing mechanisms in metal-metal bilayer systems

Mechanism of adhesion improvement in ion-beam mixed Cu/SiO2