Comdel RPMX Monitor and Control System

 
  
 

When you monitor your process from you power source, you know what power levels you are sending out, but you don't know what is actually getting to your plasma chamber.  Any number of variables in your system can cause your delivered power levels to be different from the power levels at the source.  These differences can radically affect the repeatability of your processes, not to mention those of your profits.

Luckily, Comdel has come to the rescue.  Using our own patented design, Comdel has developed the RPMX monitor.  It attaches directly to the plasma chamber to measure RF parameters...  and gives you the ultimate in profitability.
 

Accept No Substitutes!

Comdel holds the patent to this breakthrough technology that will enable you to increase yields and reduce system downtime.  Before the RPMX, power control accuracy and repeatability was only specified into a 50 Ohm load.  But Comdel's new technology enables you to control the RF power source based on the real delivered power, RF voltage, RF current, or DC bias, regardless of the load impedance.

How It Works

The RPMX is made up of two units, the Sensor Unit and the Processor Unit, which work together to give you greater precision and repeatable results.

The Sensor Unit

The Sensor Unit is placed in the transmission line, as close to the plasma chamber as possible.  The Sensor contains a DC bias tap, an RF current and an RF voltage tap.  The primary function of the Sensor Unit is to convert 13.56MHz RF voltage and current waveforms existing at the reactor terminal into accurate, low frequency representations of those parameters while preserving phase relationships.

The Processor Unit

The Processor Unit multiplies the low frequency analog signals to obtain real power and performs an RMS conversion on the signals.  It also calculates the plasma load impedance magnitude and phase angle at the Sensor Unit, and automatically adjusts the RF power source to maintain a steady power level at the plasma chamber.   Regardless of impedance levels of variations in the system, the power in the plasma chamber remains constant.
 

Repeatability in you plasma chamber process is the key to profitability in your business.  The more repeatable the results are, the lower your error rate will be, the lower your downtime will be - and the higher your profits will be.
 
 

The RPMX Eliminates Costly Variances  and  Improves Power Control 
Eliminates power accuracy errors at the power source
Eliminates loss variations due to load impedance changes
Eliminates RFG sensor errors due to RF signal modulation and harmonic distortion
Eliminates fixed and variable transmission line losses
Eliminates matching network tuning window errors
Eliminates fixed and variable matching network losses


 

The RPMX Reduces System Downtime and Improves Process Efficiency
By monitoring RF electrical parameters near the plasma load, you benefit from increased accuracy in your diagnostic data.  This data can be used to detect minute changes in the plasma load impedance, which can indicate problems or deviances in the pressure or  gas flow conditions, or even in the process gas composition itself.
As some etch processes reach endpoint, plasma impedance changes could give supporting data for endpoint detection.

 
 
General Specifications:  

Processor Unit

  • Accuracy:  5% absolute to 85 degree phase angles, 3% repeatability to 85 degrees
  • Size:  3.5"H x 9.5"W x 6.625"D
  • Weight:  5 lbs
  • Power:  100-130 VAC 50/60 Hz
  • Cooling:  Ambient, 1" min top clearance

Connectors:  

    • Sensor Unit interface:  Submin D 9 pin Female
    • RF generator interface:  Submin D 15 pin Female & Submin D 25 pin Female
    • RF Host Control analog interface:  Submin D 15 pin Male & Submin D 25 pin Male
    • Serial port:  Submin D 9 pin Female
    • RF voltage monitor output:  BNC
    • RF current monitor output:  BNC

Outputs:

      • RF voltage monitor:  5VRMS max, 4.7K Ohm
      • RF current monitor:  5VRMS max, 4.7K Ohm

      Communication Port:
       

      • DCE, 300-57.6Kbaud, 1 or 2 stop bits, 7 or 8 data bits, E/O/N parity, dip-switch selectable


      Cables:

      • AC power:  7', USA domestic standard
      • Sensor Unit interface:  5', 9 conductor,, 2 lines shielded, overall shielded, Submin D 15 pin Male connectors

Sensor Unit:

  • Size (less connectors):  2"W x 2.5"H x 3.75"D
  • Weight:  1 LB
  • Power:  Supplied by Processor Unit
  • RF voltage:  1 kV RMS max
  • RF current:  20 amps RMS max
  • Cooling:  Ambient
  • Operating Frequency:  13.56 MHz +/- 6 kHz (custom, fixed frequencies also available)
  • Bandwidth:  50 MHz

    Connectors:

    • RF:  Type N, C, UHF, HN, LC, or 3/8"-16 by .75"
    • Processor Unit Interface:  Submin D 9 pin Female