Morphology Of Copper Films Research Articles

Study of copper thick film metallization on aluminum nitride

This paper is focused on the study of copper thick film metallization on AlN. The copper metallization was realized by Thick Printed Copper (TPC) technology. The copper films were printed with a new adhesion copper paste designed for both AlN and Al2O3 substrates. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses on cross-sections have shown that the paste adhesion to AlN and Al2O3 is provided by different bonding mechanisms. The influence of different adhesion mechanisms on electrical and mechanical properties as well as the morphology of copper films on AlN and Al2O3 substrates are described in this paper.

Radiation Stability of Copper Films under Irradiation with He2+ Ions

The effect of irradiation of copper films with low-energy He2+ ions on their structural properties has been studied. The surface morphology and structural properties of the samples before and after irradiation have been examined by scanning electron microscopy, energy dispersive analysis, and X-ray diffraction. Bombardment of the initial samples with He2+ ions at a fluence of 1 × 1016ion/cm2 alters the surface morphology of copper films and leads to the formation of nanoscale inclusions of hexagonal shape. An increase in the fluence to 1 × 1017 ion/cm2 and higher results in the formation of cracks and amorphous oxide inclusions on the sample surface.

Effect of HEDP on copper electroplating from non-cyanide alkaline baths

Effects of the different concentrations of 1-Hydroxyethylidene-1,1-diphosphonic acid (HEDP) on copper electroplating from non-cyanide baths with two complexing agents were investigated by different electrochemical methods. Cyclic voltammetry and current transient measurements were used to characterise the copper electroplating system in order to analyse the nucleation and growth mechanism. The quartz crystal microbalance and chronoamperometric methods were used to study the relationship between the mass change and the deposition time. The current efficiency of electrolytes without HEDP was 95·39%. However, when the HEDP concentration was 40, 60 and 80 g L−1, the current efficiency was 93·76, 92·87 and 94·93% respectively. The structure and surface morphology of Cu films were analysed by X-ray diffraction and scanning electron microscopy (SEM). The morphology of copper films obtained with 40 g L−1 HEDP presented a smooth and compact deposit, and the size of crystal particle was uniform.

Diluting and annealing effects on electromigration and morphology of chemical vapor-deposited copper films

The crystallization and orientation of chemical vapor-deposited copper films were investigated by means of X-ray diffraction. The ratios of Cu (1 1 1) peak intensity to Cu (2 0 0) [ I(1 1 1)/ I(2 0 0)] of the film deposited at different temperatures were plotted as a function of temperature. Then it can be found that the ratio of I(1 1 1)/ I(2 0 0) increased with the deposition temperature, and 400 °C is the best one for electromigration when the films are grown in diluting N 2, and/or annealing by N 2 or by H 2. In addition, the morphology of copper films was characterized by atomic force microscopy, and it was found that the smoothness of the films grown in diluting N 2 and/or annealing by N 2 are improved, while the films annealing by H 2 have no significant changes.

Corrosion of cyanide copper deposits on zinc diecastings in acid solutions

The corrosion potential and morphology of copper films deposited from a cyanide solution on zinc diecast were studied in acid solutions similar to those employed in industry for the deposition of a second copper layer. Open circuit potential measurements and gravimetric methods were employed to determine the influence of the copper electrodeposition variables on the corrosion potential. The influence of variables such as the presence or absence of additives, the current density and the copper or cyanide concentrations were studied. The corrosion potential decreased with increasing copper film thickness. Less protection was obtained when a thin copper layer was electrodeposited from a solution without additives. Higher protection for the same thickness was obtained from a solution with high cyanide content. This result is related to the strong interaction between cyanides and the metal surface during the electrodeposition. A smooth surface structure was observed by SEM under these conditions.

The Effects of Deposition temperature on the Growth of Copper films produced by low pressure metal-organic chemical vapour deposition

AbstractCopper was deposited onto TiN by low pressure metal-organic chemical vapour deposition, using hfacCu(I)TMVS and argon carrier gas. The effects of the deposition temperature on the growth of copper films were investigated by observing the surface morphology and the cross sectional morphology of copper films. At the initial stage of growth, copper films tended to have the island-like growth mode, irrespective of the deposition temperatures. It was also observed that the aspect ratio(=height to width) of the islands gradually increased as the deposition temperature increased. The poorer movability of the copper atoms at the higher deposition temperature was evaluated on the basis of hindering effect by the following copper deposits.

Epitaxial growth of thin copper layers on Cu(111) studied by high-resolution low-energy-electron-diffraction

The morphology of ultrathin epitaxial copper films (2.5 ML) on a Cu(111) substrate is investigated by high-resolution low-energy-electron-diffraction (HR-LEED). Analyzing the spot profile of the diffracted electron beam (SPA-LEED) provides detailed information about defects of the growing film, especially steps. Thus, from the broadening of the spot the density of steps and their angular distribution are evaluated for various deposition conditions. At low temperature the film grows with nearly no diffusion of the adatoms across step edges. At high temperatures the film starts to build facets whose angles with the substrate depend on the temperature during and after deposition of the film. The annealing behaviour of a film grown at low temperature is also studied with respect to step density and asperity height. Thus the morphology of copper films under various deposition and annealing conditions can be investigated quantitatively in full detail by careful measurements and evaluation of the spot profiles.