DC sputtering Vs RF sputtering : Difference between rf and dc sputtering
Sputtering is a widely used thin-film deposition technique in industries like electronics, optics and materials science. Among the various sputtering methods, DC (Direct Current) and RF (Radio Frequency) sputtering stand out for their distinct working principles and applications. While DC sputtering is often employed for conductive materials, RF sputtering offers versatility with both conductive and insulating materials. This article dives into the core difference between RF and DC sputtering, highlighting their working principles, advantages, limitations and typical use cases.
What is Sputtering:
Sputtering is highly versatile vacuum coating system which is used for deposition of various coating materials.

Plasma gas is used ti knock atoms out of the target. As a result, atoms gets deposited on wafers as shown. Higher pressure generates better coverage. The excess energy of metal ions helps to increase surface mobility (i.e. movement of atoms on surface).
DC sputtering

• In DC sputtering, source of power is DC (Direct Current) type.
• DC power is usually preferred for electrically conductive
target materials as it is easy to control DC power.
• chamber pressure is usually 1 to 100 mTorr
• It is chaper technique when large quantities of large
substrates are dealt with.
•
In this technique, positively charged sputtering gas is accelerated
towards the target. This results in ejection of atoms which gets
deposited on substrate.
RF sputtering

• In RF sputtering, source of power is AC (Alternating Current).
Instead of DC voltage to cathode, RF at about 13.5 MHz is being applied.
• RF peak to peak voltage is 1000 V,
electron densities are 109 to 1011 Cm-3 and
chamber pressure is 0.5 to 10 mTorr
• RF power is suitable for all the materials but
most commonly used for depositing films from dielectric target
materials.
• Deposition rate is low compare to DC sputtering.
• It is used for smaller substrate sizes due to
high cost factor of RF power supplies.
• The RF sputtering consists of two processes.
In the first cycle, target material is negatively charged.
This causes polarization of atoms.
The sputtering gas atoms are attracted towards source where they
knock out source atoms. Here source atoms and ionized gas ions remain
at target surface due to polarization of target.
• In the second cycle, target is positively charged.
This causes ejection of gas ions and source atoms due to
reverse polarization.
These are accelerated toward substrate and hence deposition will occur.
Difference between rf and dc sputtering
Following table summarizes core differences between RF and DC sputtering techniques.
Features | DC Sputtering | RF Sputtering |
---|---|---|
Sputtering type | Magnetron only | Magnetron or diode |
Target materials | Conductive only | All the targets |
Power Source | Uses a direct current (DC) power source. | Uses a radio frequency (RF) power source, typically 13.56 MHz. |
Material Suitability | Suitable only for conductive materials. | Suitable for both conductive and insulating materials. |
Target Charging | Cannot sputter insulating targets due to target charging. | Prevents target charging through alternating RF electric fields. |
Complexity | Simple setup and operation. | More complex setup due to the RF power source and matching network. |
Cost | Lower equipment cost. | Higher equipment cost due to RF generators. |
Deposition Rate | Generally higher deposition rates for conductive materials. | Deposition rates are often lower than DC sputtering. |
Applications | Commonly used for metal films and conductive coatings. | Ideal for dielectric, insulating, and mixed-material films. |
Plasma Generation | Relies on a steady plasma for material removal. | Alternating RF fields sustain a stable plasma even with insulating materials. |
Maintenance | Easier maintenance due to simpler components. | Requires more frequent tuning and complex maintenance. |
Efficiency | Higher efficiency with conductive materials. | Lower efficiency but more versatile material handling. |
Sputtering rate | 100% of DC | 20% of DC, no magnetron |
Compaign length (i.e. loss of anode) | Good | Excellent |
Conclusion
Both DC and RF sputtering are essential thin-film deposition techniques, each suited to specific material requirements and applications. DC sputtering excels in simplicity and efficiency for conductive materials, while RF sputtering’s versatility makes it ideal for a wider range of materials, including insulators. Understanding these differences ensures the right method is chosen for a given application, optimizing performance and quality.
What is Difference between
Difference between SC-FDMA and OFDM
Difference between SISO and MIMO
Difference between TDD and FDD
Difference between 802.11 standards viz.11-a,11-b,11-g and 11-n
OFDM vs OFDMA
CDMA vs GSM
Bluetooth vs zigbee
Fixed wimax vs mobile