Influence of Substrate Bias Voltage on the Properties of Cu Thin Films by Sputter Type Ion Beam Deposition

Abstract

Cu thin films have been deposited on Si (100) substrate by using a non-mass-separated ion beam deposition (IBD) system. The effect of the substrate bias voltage on the properties of the deposited films was investigated using X-ray diffraction, resistivity measurement and field emission scanning electron microscopy. In the case of Cu thin films deposited without bias voltage, a columnar structure and small grains were observed distinctly, and the electrical resistivity of the deposited Cu films was very high. By increasing the bias voltage, no clear columnar structure and grain boundary were observed. The resistivity of Cu films decreased remarkably and at a bias voltage of −50 V, reaching a minimum value of 18 ± 1 n m, which is close to that of the bulk phase (16.7 n m.)

Atomistic details of oxide surfaces and surface oxidation: the example of copper and its oxides

“…All three methods present some drawbacks (diffuse white light does not provide a value for the thickness and relies on visual checking of the surface colour, ellipsometry relies on a guess model and Rhodin's method depends on an accurate estimation of the effective area of the resulting oxide) and it is difficult to tell which of the three is more reliable. The difference observed could also be the result of environmental factors such as the presence of impurities or different sample preparations, which have been shown to lead to different resulting metal oxides 275,276 which makes oxidizing metals very challenging to study.…”

“…Indeed, the formation of a ∼ 2.0 − 5.0 Cu 2 O layer first, followed by a ∼ 0.9 − 1.3 CuO overlayer has been reported 3,4,291,292 . However, Lim et al 276 showed that the texture and microstructure of a thin copper film have a direct influence on the oxidation products. When oxidising a sample with a columnar structure and small grains the Cu 2 O/CuO bylayer was obtained, when oxidising a uniform sample with no obvious columnar structure and grain boundaries the cuprous oxide layer only was observed and oxidation was slower.…”

Effect of Sputtering Power on the Nucleation and Growth of Cu Films Deposited by Magnetron Sputtering

“…[1][2][3] Thin films of Cu are deposited by various techniques such as evaporation, sputtering, chemical vapor deposition, electroplating, and ion beam deposition. [4][5][6][7][8][9][10][11] Among these techniques, direct current (DC) magnetron sputtering is one of the best methods for practical preparation of Cu films. Since DC magnetron sputtering technique has the advantage of much better productivity than other deposition methods, it is widely used as mass production processes.…”

Agglomeration of Copper Thin Film in Cu/Ta/Si Structure

“…14,15) In order to investigate copper agglomeration with annealing time, the Cu/Ta/Si structure was annealed for 1 to 60 min at 650 C in H 2 atmosphere. Resistivity measurement of annealed samples was carried out with Van der Pauw method.…”