Untitled

Nucleation and growth of copper under combined charge transfer and diffusion limitations—Part II

“…With increasing the overpotential the transients attain distinct current maxima characterizing the progressive and instantaneous nucleation with overlap of diffusion zones (see e.g. [8,[11][12][13][14][15][16][17][18][19][20]). This is particularly true for the semiconductor substrates [21,22] on which deposition of copper takes place at extremely high cathodic overpotentials.…”

Experimental and modeling analysis of the formation of cuprous intermediate species formed during the copper deposition on a rotating disk electrode

“…Comprehensive models for the electrodeposition of copper in acidic sulfate media have reported that Cu 2+ ions in solution are reduced in two consecutive 1-electron transfer steps [1][2][3][4][5][6][7][8][9][10][11][12]. This reaction pathway involves the formation of intermediate cuprous species.…”

“…In the literature, a clear distinction has been made to describe the phase of this intermediate formed in the first reduction step. Some studies [1][2][3][4][5][6] report that the cuprous species is adsorbed (Cu(I) ads ) on the substrate, whereas other authors [7][8][9][10][11][12] suggest that it is a soluble species (Cu + ) located on the solution side and close to the surface of the electrode.…”

“…The generation of very small amounts of Cu + in solution by deposition has been reported in deoxygenated solutions at low cathodic overpotentials on the basis of rotating-disc electrode studies [7][8][9][10][11][12], even when ligands (i.e. chlorides) to stabilize Cu + ions are not used in solution [17].…”

Influence of organic additives on the initial stages of copper electrodeposition on polycrystalline platinum

“…This last technique offers many advantages: it is the least expensive, it has the highest deposition rate, the lowest toxicity and is readily adoptable [1][2][3]. The main electrolytes used for copper electrodeposition are acidic and contain copper sulfate as a metal source [1,[4][5][6][7][8], but apparently electrical properties as well as resistance to corrosion have to be warranted. This can be achieved by small amounts of organic additives, such as DPS [9], PEG [9][10][11][12], SPS [10,11], IT-85 [13,14],thiourea [13,[15][16][17][18][19][20][21][22][23][24], to the copper electrolytes.…”