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PHI 5600: Mounting Samples Procedure

The RBD instructions for the bake-out procedure of the PHI 5600 can be found here, these notes are a summary of those notes with some of our own details. Here are some notes produced by Summer student Andrea Valdez-Rivas.

INTRODUCTION

The loading and unloading of samples in the PHI 5600 is done through the loading arm, this way only a smaller section needs to lose the low pressure existing in the chamber.

In summary, for unloading the arm pressure gate must be open, pressure equalized in arm and chamber, sample holder should be mounted on arm, sampler holder retrieved, gate closed, sample holder removed from system.

For loading the sample holder should be positioned on arm, pressure  in arm should be brought down, gate must be open, pressure equalized in arm and chamber, arm with sample holder introduced in chamber, arm should be retrieved, and gate closed.

PROCEDURE

For loading and unloading start by making an annotation in the XPS log book stating your name, date and time, pressure readings, and description of sample holder or samples being removed.  Notice that high pressures (> 10-7 Torr) could indicate problems and should be brought to the attention of the operators.

Unloading Samples 

Inspect location of sample holder in chamber. Use micrometers to position sample holder in correct position.

     open

Check position of loading arm, push "Backfill Intro" in "Auto Valve Control" in the remote cotrol keypad, wait until "TC1" reaches "AIR" setting, Remove cover window, remove sample holder.

       

Loading Samples

Start by selecting the sample holders to be used, there are different types that work best for different sizes.  Samples and sample holders should be manipulated only while wearing gloves, and wiped with a Kimwipe moistened with isopropanol. Use the screws on the stub to mount your sample securely. If you must use carbon tape (only UHV carbon tape is allowed), use only a very small amount and do not load more than 3 samples with carbon tape at one time. Samples should not extend past the edges of the holder. Place the holder onto the load lock arm. The bottom notch of the holder should fit snugly into the arm. Close the load lock door.

Load samples on sample holder, when the intro chamber is backfilled, insert the sample holder into open window, replace the cover and press "Pump Intro" button.

     

Wait five minutes for pressure to drop to "Hi Vac", the pump down will be complete when indicated by all five red lights being lit on the TC1 display of the Auto Valve control, monitor pressure until drops down to 10-8 Torr, press the "Intro Sample" button and slowly push the rod into the main chamber and transfer the sample holder onto the sample stage.

    

To position the sample holder:

To adjust position, turn the light source on, move the stage up or down, Use the transfer arm to move the holder into the analysis chamber, move the transfer arm slowly when placing the stub on the stage. The holder is fully on the stage when the collar above the spindle completely overlaps the semicircular wear mark on the stage. If you cannot load the sample using minimal pressure, ask for help. Do not use excessive pressure as it can damaged the stage.  Unlock the sample holder from the transfer arm.  While watching the holder on the sample stage, withdraw the transfer arm slowly. If the holder starts to move push it back onto the stage and try again. If you cannot get the stub to stay on the stage ask for help.  Move the transfer arm back to the load lock chamber, and close the gate.  Raise the stage into the appropriate position to collect data. If the gears on the stage and the stub do not mesh, try rotating the joystick.

When the transfer is complete, withdraw the intro. rod, valve V1 will close automatically and isolate the main vacuum chamber from the intro. chamber.

Adjust position of sample holder, check X-ray source does not obstruct sample holder (move up if needed), move arm out slowly, check position of sample on screen.

     

To position sample turn on the fiber optic light source and view the sample holder on the video monitor. Position the desired analysis area in the center of the field of view Using the knobs on the sample stage.  Adjust the stage so the analysis area is in focus. Check the pressure throughout the procedure. With the desired analysis area in focus and located at the center of the field of view, you can be relatively confident that you are analyzing the correct area of the sample. Positioning errors using this method are typically less than 100 μm. If you are using the smallest analysis area of 30 μm and higher precision is required, it is suggested that you collect an ESCA map and select the desired area from the map data.

Prior to collecting ESCA data, it is recommended that you create or select the desired directory for data storage and that you select the Sample Setup function under the Sample Setup pull down. In this screen, you can define a prefix for the data file, a starting file number, and comments to be stored with the data file.

  

 

CONTACT: Jorge A. López (jorgelopez@utep.edu

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