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Matching Network Efficiency

Matching Network Efficiency

Your company has paid a large sum of money for a piece of complex RF process equipment and your RF power supply is rated to 1% accuracy. That will give you great confidence that the process will be reliable and repeatable. 

However, if 10 – 50% of that accurate power is lost in the matching network does that change things?   Would you like to know how efficient your matching unit is? 

So, even if 50% of the power is lost in the matching unit; you can probably learn to live with that as long as it is the same every time, Right!  But, what if the match efficiency is not constant and changes every time you change the process gas flow, the gas type or the chamber pressure, that would not be so good, would it?

RF Matching Network Range

Step 1 - Connect an inline power meter, the Octiv Mono ( mono 1) to the output of a 50Ω load. We are going to measure the range with power applied so make sure the load can handle the power. The power meter is optional but it will be useful if you want to measure the Efficiency of the Network.

Matching Network Quality

The match unit or matching network is a key component in getting power from an RF power supply to a plasma. The output of the power supply has a typical impedance of 50 Ohm. To match this to a plasma or other dynamic load we need a matching network. The matching network plays two key roles i) it presents a reactive impedance equal and opposite to the load so that the reactive components cancel and ii) it matches the real resistance of the load to the 50 Ohms of the RF power supply.

Hot spots and flash points

Hot spots and flash points rf technology

We recently got a returned Octiv sensor with the connector melted and this reminded me of hotspots and flashpoints.

In the world of RF engineering transmissions lines are matched and current and voltage are uniform along the cable. In the plasma world transmission lines are used to carry power to the plasma. A matching network is used to match the power supply to the plasma but the connection, effectively a transmission line from the matching network to the plasma electrode is not matched. I am not an RF engineer but even a physicist knows that there is a reflected wave at the end of the unmatched transmission line.

Why Lawrenceville Plasma Physics Results are Not Even Wrong; a Detailed Analysis.

I recently responded to a claim from Lawrenceville Plasma Physics that they were close to a commercial fusion reactor.  I was annoyed that such claims were being made and even more concerned that such claims were not receiving a strong criticism fr

Plasma Physics Division Annual Report

The inaugural edition of the Plasma Physics Division Annual Report, from the Drexel Institute of Plasma Physics Division is available online - quoting from the release

The 9th Workshop on Frontiers in Low Temperature Plasma Diagnostics

The 9th Workshop on Frontiers in Low Temperature Plasma Diagnostics (FLTPD) was held in Zinnowitz, near Greifswald, Germany.  FLTPD is a biennial European event in which scientists working on low-temperature plasmas present their recent results, pointing out in particular the originality of the diagnostic techniques used.

The 9th Workshop on Frontiers in Low Temperature Plasma Diagnostics

The 9th Workshop on Frontiers in Low Temperature Plasma Diagnostics (FLTPD) was held in Zinnowitz, near Greifswald, Germany.  FLTPD is a biennial European event in which scientists working on low-temperature plasmas present their recent results, pointing out in particular the originality of the diagnostic techniques used.

PULSED PLASMA DIAGNOSTICS WORKSHOP

Registration: www.impedans.com

Hosted by: Impedans ltd

Venue: Crowne Plaza Hotel, Santry, Dublin 9, Ireland

New Managing Director for Plasma Technology

Oxford Instruments Plasma Technology has appointed Dan Ayres to Managing Director with immediate effect. Dan previously held the position of General Manager at the company, and prior to this was Operations Director. With over 10 years experience within the Oxford Instruments Group, Dan has held roles in the fields of Operations, Product Management and Project Management.

Plasma - an art rather than a science.

I recently came across an article that described the soul as a plasma, a transitional phase between matter and energy. The essay was accompanied by the beautiful pictures of plasma globes that have become so common. There was a stage in my life/career as a physicist that this would annoy me.

Paper review - Ion energy distribution measurements

Ion energy distribution measurements in rf and pulsed DC plasma discharges

D Gahan, S Daniels, C Hayden, P Scullin, D O'Sullivan, Y T Peiand M B Hopkins.

http://stacks.iop.org/0963-0252/21/024004

Carrington event which is a massive plasma flare from the sun could hit the earth in the next decade

Startling paper by Pete Riley on the possibility of  massive solar flare, or Carrington event happening-

Key Points

  • Probability of a Carrington event occurring      over next decade is ~12%
  • Space physics datasets often display a      power-law distribution
  • Power-law distribution can be exploited to      predict extreme events

Pete Riley

the UCLA plasma simulation group received $1.78 million from the National Science Foundation (NSF)

Some recent good news for the UCLA plasma simulation group.  The group recently received $1.78 million from the National Science Foundation (NSF) to develop a cluster of 192 General Purpose Graphical Processing Units to compute at “Warp” speed. This new cluster is named DAWSON2 in honour of the group’s founder. DAWSON2 is dedicated for the study of particle-in-cell simulations of plasmas.

Princeton, Max Planck Society launch new research center for plasma physics

Princeton, Max Planck Society launch new research center for plasma physics Princeton University

"This collaboration with Germany's distinguished Max Planck Society is certain to enhance our common excellence in fusion and plasma astrophysical research and, more broadly, to advance the development of clean and abundant energy," Tilghman said.

Plasma sabre disinfects. Wash yourself with a plasma and get a healthy glow

Atmospheric plasma created in air are known to kill bacteria. The killing effect is not fully understood but it results from the very reactive nature of the plasma. To explain this the typical atmospheric plasma is a non-equilibrium plasma. This means that the electrons are accelerated by the strong electrical field.

Arc Direct!! Now lightning can strike twice in the same place

Arc Direct!! Now lightning can strike twice in the same place. Lasers have been used for the first time to trigger and divert lightning bolts.

http://www.newscientist.com/article/mg21328584.200-lightning-directed-by...

Plasma are beautiful

purchase a beautiful plasma

photo by Mitchell Buchanan by @mitcheplasma are beautifulllsmind

http://mitchellbuchanan.wordpress.com/

Not even wrong, Fusion Energy at Lawrenceville Plasma Physics

When I was a postgraduate student I published my first scientific paper. I was very worried that the paper would be inaccurate. I spent several months reviewing the content before I finally submitted the work for publication.

Run away reaction to ping pong balls

Interesting article here on using ping pong balls loaded on mouse traps to demonstrate a nuclear fusion reaction in Illinois. The demo was part of a student lead project.

http://npre.illinois.edu/news/ans-students-demonstrate-nuclear-reactions...

Lithium lighter than water

Lots of plasma fusion stories this week, lithium lining work at PPPL. I notice the article points out that lithium is so light it floats in water – not for very long. Puff!!

http://www.princeton.edu/main/news/archive/S33/23/37O88/

Electrodeless propulsion technology

The Elwing Company has established itself as a leader in the development of electrodeless plasma propulsion technology, having pioneered breakthrough electrodeless propulsion technology and tested it comprehensively in the U.S.

That empty feeling, when everything sucks!

Always a great question - what happens to somebody when exposed to a vacuum? I always liked this question. If we were unlucky enough to be sucked out of the airlock, like in alien - what would happen? Would we explode, blood and guts everywhere. Would it take time to die? Well, when I saw this article I thought it was an April fools story, but the release is dated the 3rd of April.

Recently published online – Fundamentals of Ionized Gases: Basic Topics in Plasma Physics

Recently published online –

Fundamentals of Ionized Gases: Basic Topics in Plasma Physics

Author Boris M. Smirnov

Details of the book can be found here

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