There are many kinds of electroplating. Do you mean water electroplating?
The film thickness of water electroplating is thicker than that of vacuum sputtering, and the thickness of hydropower coating is generally 15~20UM. vacuum plating
The film thickness is generally 0.5~2UM. Different water electroplating chemical solutions will have different colors.
The coating color of different vacuum coating targets is different, and the power and vacuum of vacuum coating will change color.
snap
Sputtering is to bombard the target with argon ions, and the atoms of the target become vapor deposited on the substrate. Sputtering is widely used, and almost any material can be deposited.
1)
Advantages and limitations of sputtering
I)
superiority
answer
contamination free
b)
multipurpose
c)
Good adhesion
2)
limit
answer
The manufacture of the target is limited.
b)
Damage to targets such as ceramic targets limits the range of energy used.
c)
Low deposition rate
2)
Sputtering system
I)
classify
answer
Plane bipolar type: the target is negative and the substrate is positive.
b)
Tripole: A system consisting of an anode, a cathode and an external electron source. An external electron source generates an electric field to accelerate the gas molecules ionized by the anode. Triode system can not be used for reactive sputtering, because electrons will affect the reaction gas and pollute the filament.
c)
Magnetron sputtering: using magnetic field to improve sputtering rate.
d)
Reactive sputtering: introducing reaction gas into vacuum chamber to react with metal atoms to generate compounds for electroplating.
2)
Water flow classification
answer
Dc sputtering-applied to conductive substrates and coatings
b)
Alternating current (or radio frequency) sputtering-applied to conductive or non-conductive substrates and coatings.
3)
Sputtering system combination
I)
Target material
In the sputtering process, the coating material deposited on the substrate is bombarded by positive ions in the plasma; The target is usually the cathode.
2)
Sputtering flux
The flux during sputtering is the flux of sputtering atoms. The composition of flux atoms is the same as that of the cooling target without internal diffusion. The sputtering rate of all materials in the same target is almost the same. (But the evaporation rate of evaporation is different).
(3)
Grounding shield
Limit ion bombardment and sputtering targets; Avoid splashing the target fixture. The distance between the shield and the target must be smaller than the dark area (darkness
Space) thickness, therefore, in high frequency (13.5MHz) or high voltage use, this distance is close.
4)
protective equipment
A movable plate arranged between two electrodes. Generally, when the cleaning target is splashed (the target may be polluted by the atmosphere during loading or operation), it moves between the target and the substrate.
V)
Cooling of target material
When external energy is input into the system, the temperature of the target will rise, and the combination between the target and the fixture will be destroyed, so it must be cooled. Generally speaking, the target is cooled with water.
6)
Control of substrate temperature
Use resistance and light source for heating. Generally speaking, due to glow discharge, the surface temperature of the substrate will be higher than that of the main material.
4)
Sputtering of insulator
The insulating film may be sputtered by RF or reactive sputtering. If DC sputtering is used, it will soon lead to the accumulation of surface charges and it will be impossible to sputter.
I)
Radio frequency sputtering (RF
Sputtering)
The frequency of use is 13.56.
MHz RF power supply makes the target surface and coating alternately bombarded by ions and electrons to avoid the accumulation of charges.
2)
Advantages of RF sputtering
answer
The efficiency of electron bombardment ionization is improved, and the operating pressure is relatively low (
b)
Reduce arcing (arcing is caused by dust or heated vaporized gas)
(3)
reactive sputtering
spuutering)
A reaction gas, such as Ar, is added to argon.
+
H2S and sputtering atoms, such as cadmium, form cadmium sulfide. (For example, titanium nitride will be formed by sputtering titanium in argon and nitrogen). It can be DC or RF reactive sputtering.
5)
Magnetron sputtering
Sputtering)
"Magnetron" refers to "magnetized electrons" (Magnetical
Electronic)
I)
merits and demerits
Although magnetron sputtering will improve the sputtering rate, it will also accelerate the loss of the target. Because the distance between the substrate and the plasma is large, the substrate is far away from the plasma and can be sputtered at a lower working temperature.
2)
operational approach
It is composed of vertical electric field and magnetic field. Due to the electromagnetic interaction, electrons are concentrated near the target, which enhances the ionization effect, as shown in the following figure.
answer
The magnetic field will form a gathering place of electrons on the surface of the negative electrode, and ions will gather due to the electrostatic action of the limited electron source.
b)
Electrons can be effectively concentrated on the target surface, which improves the ionization efficiency and sputtering rate.