Electrochemical deposition
Coolidge
www.diecastingpartsupplier.com
2018-09-03 11:31:02
Electrochemical deposition
Electrochemical deposition is generally used for the growth of metals and conducting metal oxides because of the following advantages: the thickness and morphology of the nanostructure can be precisely controlled by adjusting the electrochemical parameters; relatively uniform and compact deposits can be synthesized in template-based structures; higher deposition rates are obtained; and the equipment is inexpensive due to the non-requirements of either a high vacuum or a high temperature reaction. [6] [7] [8]
Press electroplating or press electrodeposition (PED)
A simple modification in electroplating is electroplating. This process involves the swift alternating of the potential or current between two different values resulting in a series of pulses of equal amplitude, duration and polarity, separated by zero current. By changing the pulse width and width, it is possible to change the deposited film's composition and thickness. [9]
The experimental parameters of pulse electroplating usually consist of peak current / potential, duty cycle, frequency and effective current / potential. Peak current / potential is the maximum setting of electroplating current or potential. Duty cycle is the effective portion of time in certain electroplating period with the current or potential applied. The actual current / potential is calculated by multiplying the duty cycle and peak value of current or potential. Pulse electroplating could help to improve the quality of electroplated film and release the internal stress built up during fast deposition. Combination of the short duty cycle and high frequency could lower the surface cracks. However, in order to maintain the current current or potential current, the high performance power supply may be required to provide high peak current / potential and fast switch. Another common problem of electroplating is that the material could get plated and contaminated during the reverse electroplating, especially for the high cost, inert electrode like platinum.
Other factors that could affect the pulse electroplating include temperature, anode-to-cathode gap and stirring. Sometimes the electroplating can be performed in heated electroplating bath to increase the depositing rate since the rate of almost all the chemical reaction increases exponentially with temperature per Arrhenius law. The anode-to-cathode gap is related to the current distribution between anode and cathode. Small gap to sample area ratio may cause uneven distribution of current and affect surface topology of plated sample. Stirring may increase the transfer / diffusion rate of metal ions from bulk solution to the electrode surface. Stirring setting varies for different metal electroplating processes.
Electrochemical deposition is generally used for the growth of metals and conducting metal oxides because of the following advantages: the thickness and morphology of the nanostructure can be precisely controlled by adjusting the electrochemical parameters; relatively uniform and compact deposits can be synthesized in template-based structures; higher deposition rates are obtained; and the equipment is inexpensive due to the non-requirements of either a high vacuum or a high temperature reaction. [6] [7] [8]
Press electroplating or press electrodeposition (PED)
A simple modification in electroplating is electroplating. This process involves the swift alternating of the potential or current between two different values resulting in a series of pulses of equal amplitude, duration and polarity, separated by zero current. By changing the pulse width and width, it is possible to change the deposited film's composition and thickness. [9]
The experimental parameters of pulse electroplating usually consist of peak current / potential, duty cycle, frequency and effective current / potential. Peak current / potential is the maximum setting of electroplating current or potential. Duty cycle is the effective portion of time in certain electroplating period with the current or potential applied. The actual current / potential is calculated by multiplying the duty cycle and peak value of current or potential. Pulse electroplating could help to improve the quality of electroplated film and release the internal stress built up during fast deposition. Combination of the short duty cycle and high frequency could lower the surface cracks. However, in order to maintain the current current or potential current, the high performance power supply may be required to provide high peak current / potential and fast switch. Another common problem of electroplating is that the material could get plated and contaminated during the reverse electroplating, especially for the high cost, inert electrode like platinum.
Other factors that could affect the pulse electroplating include temperature, anode-to-cathode gap and stirring. Sometimes the electroplating can be performed in heated electroplating bath to increase the depositing rate since the rate of almost all the chemical reaction increases exponentially with temperature per Arrhenius law. The anode-to-cathode gap is related to the current distribution between anode and cathode. Small gap to sample area ratio may cause uneven distribution of current and affect surface topology of plated sample. Stirring may increase the transfer / diffusion rate of metal ions from bulk solution to the electrode surface. Stirring setting varies for different metal electroplating processes.