Answers_to_Questions.docx

Answers to Questions for NB686040-15-03301

1) You ask for one ion source for Ion-Assisted Deposition. There are a few types of ion sources with different ranges of energy and ability to operate in oxygen. The most likely best source for this system would be an End Hall source that can run with O2 gas and provides beam energies in the range of 50 to 300 eV. Is this the type of source you had in mind?

This ion source can work for our applications. We would also like to be able to work with inert gases as well, in addition to O2 gas.

2) If not, please provide the ion beam energy you would like to work with and oxygen background pressure you expect to run at.

3) What materials will the IAD be used for? Only metals, or only dielectrics, or both?

The IAD will be used primarily for dielectrics deposition, but we may explore metal depositions as well.

4) In order to run magnetrons and an ion source you face the challenge of dealing with two different pressure ranges in the same chamber. The magnetrons want to run at pressures typically in the range to 2 to 10 mTorr. The ion source runs best at pressures below about 4 x 10-4 Torr. If the pressure is higher the ion beam is severely attenuated due to the high pressure. Thus, you most likely require gas injection into each magnetron source and a very large pumping speed to keep the main chamber pressure low enough for the ion source to function properly.

Gas injection at each magnetron source is required.

5) You ask for a turbo pump but do not specify the size. Did you have a certain pumping speed for the turbo pump in mind?

The required parameter is not the pumping speed but the base pressure which will depend on the chamber volume. We require at least 5x10-8 Torr base pressure.

6) You request a mechanical pump. Do you mean an oil based pump or a dry pump?

An oil based pump is acceptable.

7) I assume all valves for the pumping system are pneumatic. Please confirm.

Pneumatic valves are required.

8) You ask for a single DC power supply and four was DC switch. You also request that at least two magnetron sources should be compatible with both RF and DC Power supplies. Do you expect to have an RF/DC Switch box for each of these magnetrons? Or will you plan to change cables manually?

Plan to change cables manually.

9) The acceptance testing has no provision to test the ion source during sputtering. Will this be required?

YES.

10) You ask for 3 OR 4 magnetrons. Should the chamber be designed for four magnetrons even if three are offered?

Minimum of 3 magnetrons are required, does not have to be designed for four.

11) You ask for a base pressure of 5 x 10-8 Torr. You can easily reach this temperature with standard, non UHV Magnetrons. Are UHV Magnetrons mandatory?

The magnetron sputter sources should be able to operate in a chamber that routinely reaches base pressures of 5x 10-8 Torr.

12) Also, does the customer care if the system is sputter up or sputter down?

Both sputter up and sputter down configurations are acceptable.

13) What type of end point detection are you looking for? This can greatly affect the geometry of the chamber.

We are planning for a laser interferometry endpoint detector system upgrade. This would require direct line of sight from chamber port to the substrate.

14) Is there a specific angle you want the ion source to impinge upon the substrate? Or is 90 degrees acceptable?

Reading literature on Ion Assisted deposition it seems that most configurations allow for an angle 75-45 degrees from sample normal of the ion assisted beam. I would be interested in finding out more, your company has evidence of good quality dielectric films grown with the ion assisted beam impinging at normal incidence?