Maybe you are facing arcs on the table. Do you see any residual of electric burns on parts/samples? If it happens after 4 batches, maybe something get coated and not more enough conductive.

Nothing on my samples . no burns . Film is also not deposited

Did you check that the bottle of Argon is not empty?  If there was suddenly less Argon flowing in the chamber, the pressure may get lower and in some cases, it means a more intense glow (mean free path of electrons and ions gets larger and they gain in energy, but not flow).  That could also explain the absence of deposited film (flow towards the target is not enough, and you may get some etching from the plasma to the substrate due to the long mean free path).

Just an idea.  It may be due to something completely different.

It may be due to the flakes or uncleanliness

One big question is the Voltage .It is almost two to three times higher than the normal one and the plasma density was very low. not the bright blue plasma that is normal to be seen

Hi Johneph,

I have two qeustons which are quite essential to answer your question. What material are you sputtering and what kind of system do you use (DC, RF, DC-magnetron, RF-magnetron)?

DC sputtering and gold @ Peter

I suppose you work with a constant current source? Higher voltage and no or little plasma could have several causes.

1. Pressure in the chamber is way too low. Check the pressure gauge. Can also be a pressure gauge failure, i.e. erroneous high readings from the gauge; or closed shutters or valves.

2. Wrong gas. Would also lead to a very different color than the usual Argon pink/purple.

3. Electrical connection problems between target and power source. Target delaminated from holder? Connectors loose? Cable break? Power supply failure? Wrong target or power source connected? Edit: Or vacuum feedthrough failure?

4. Wrong target. Perhaps an RF target for ceramics instead of gold?

5. Insulating layer deposited on target, for example in a deposition chamber for multiple materials.

6. Wrong power source, RF instead of DC?

Hi Dieter,

I have been using the same target since last month and it seems to me that due to uncleanliness it happened .

As mentioned by the others you might have a problem with contamination. If that contamination is an oxide your DC supply will not be able to run current through the plasma, the voltage will go up and no layers are deposited. I don't know how you can sputter oxides on top of the gold but maybe you did have some parasitic plasma sputtering off some ceramic isolation material. In that case you can only solve the problem by gently cleaning your gold target. The other suggestions of too low pressure or a bad power connection of cable break are also possibilities you do not have plasma. This can easily be checked with an ohm meter and I advise you to do this first before you clean/polish the gold target.

Some other simple yet possible problem could be loss of magnetization if you are using a magnetron.  Happened in my old lab after somebody forgot to switch on the cooling water and fried the magnets,  i. e.  diode configuration,  no electron confinement,  high voltage,  low deposition rate.

The problem is solved by replacing a new gold target

Hi Johneph,

Was the gold on the old target completely gone? Or was there a non-conductive layer on the old target or a bad electrical connection?

Hi Johneph,

Keep in mind, during sputtering, the magnetic field on the target is also affects the sputtering process. If I am not wrong, there is two possibilities

1- due to no cooling or week cooling magnets have no field. OR

2- Target is poison

I believe in your case is target poisoning. Always, remember sputtering any target requires quick target cleaning process by bombarding or sputtering Sometimes without knowing target reacts with the environment and forms insulating layers. So, it is good to perform target cleaning process first before the actual coating.

I hope it is clear to you now.

Dear Johneph Sukham,

Low pressure glow discharge sputtering is frequently useful in materials processing. Example, sputter deposition and other ion assisted growth techniques are essential for production of semiconductor devices, hard wear resistant coatings and for various optical thin films. Also plasma assisted etching techniques and plasma polymerizations are extensively used in many industrial processes.

Glow discharge is similar to sputtering, but instead of ions from the plasma ejecting the material from the target, a chemical reaction is initiated in the gas phase by creating a radio frequency glow discharge of the reactant gas, leading to the deposition of the solid form on a substrate placed inside a chamber.

Here, sputtering yield in a glow discharge ion source system can be determined using the operating parameters of the ion source. The feature of this ion source is high output ion beam current and small size. Operation of the ion source is quite simple since a stable discharge can be obtained within a large range of main parameters such as, discharge voltage, discharge current and gas pressure. At the same current density, the rate of sputtering in case of argon gas is higher than that for pure nitrogen gas. This ion source can be used for etching, sputtering and micro-machining applications.

Ashish