11-010 Electron Gun Control modification to reduce noise

Print Friendly, PDF & Email

Due to aging components, many of the PHI 11-010 5kV electron gun controls have developed a slight noise problem in the emission chopper circuit on the 623 board that results in about 300 mV of 60 hz ripple on the emission voltage, which translates into noise in the electron beam and Auger data.

Since the chopper circuit is never used (it was designed as a way to get N/E data with a lock-in recorder), a very simple solution to the problem is to bypass the chopper circuit.

Procedure:

  1. Unplug the 11-010 AC power cord and remove the cover.
  2. Solder a jumper between Pins 17 and 18 on the 623 board as shown below.  The 623 board is located on the side of the 11-010, just above the filament supply board.

This modification will reduce the noise level from about 300 mV to 50 mv or less and results in noticeably cleaner Auger data.

Chopper board resistors
This jumper will bypass the Chopper board circuitry
Chopper board schematic
Jumper location on Chopper board

PHI 5600 XPS system Bakeout procedure to improve base vacuum

Gallery

This gallery contains 28 photos.

Print Friendly, PDF & Email

Updated 8-30-19 This post explains the bakeout procedure to improve base vacuum in a PHI 5600 X-ray photoelectron spectrometer. The procedure is basically the same for most of the older PHI (Physical Electronics) Spherical Capacitive Analyzer XPS surface analysis systems. … Continue reading

Sputter rate standard

Print Friendly, PDF & Email

Why do you need sputter rate standards anyway? Each ion source will produce a different sputter rate depending on the conditions that the ion source is operated at, as well as other factors such as the angle of the ion source to the sample. Changing the beam voltage, condenser and focus (beam size), pressure (amount of argon or other gas) and raster area all affect the sputter rate. By using a sputter rate standard you can characterize your ion source for a particular set of operating conditions for a known oxide layer thickness of standard material (Ta2O5 or SiO2).

To further complicate things, the sputter rate of different materials varies greatly and that makes it very difficult to accurately know the true sputter rate for compounds and multi layer samples.

The link to this SPECs article for some very helpful insights into sputter rates on different materials:

Sputter Rate Information

And, here is a link to a PNNL publication on the sputter rates of oxide films relative to SiO2.

TaO5 sputter rate standard

RBD Instruments provides a 1000 Angstrom oxide layer TaO5 sputter rate standard which is approximately .75 X .50 inch in size.  Both sides of the standard can be used, so one standard can last a long time.   The RBD part number is TA2O5RE.

SiO2 sputter rate standard

RBD Instruments  provides a 1000 Angstrom oxide layer SiO2 sputter rate standard which is approximately .50 X .50 inch in size and comes in a two pack.  The RBD part number is SIO2CALRE  and like the TaO5 standard, both sides can be used.

To request a quote for either standard, contact RBD here or go to the upper right hand corner of the RBD Instruments website and create a sales ticket. (www.rbdinstruments.com)