STANDARD OPERATING PROCEDURE: RIGAKU RU 300 XRD POWDER SAMPLES

Transcription

1 STANDARD OPERATING PROCEDURE: RIGAKU RU 300 XRD POWDER SAMPLES Purpose of this instrument: The Rigaku RU 300 XRD is used for phase analysis of polycrystalline films, characterizing single crystal, and epitaxial films, and powders. Location: 402 White Hall Primary Staff Contact: Harley Hart (412) cell Secondary Staff Contact: Weiqiang Ding (304) cell The Shared Research Facilities are operated for the benefit of all researchers. If you encounter any problems with this piece of equipment, please contact the staff member listed above immediately. There is never a penalty for asking questions. If the equipment is not behaving exactly the way it should, contact a staff member. WARNING: This system generates x rays. A radiation dosimeter MUST be worn at all times while using the instrument. START UP 1. Ensure the radiation dosimeter is attached to the person. 2. Sign in on the FOM and the system log book located on the XRD computer bench. Figure 1: Screenshot of FOM login page 3. Enter the water recirculator room and verify that the water recirculator reservoir is full as shown in Figure 2. This is indicated by the yellow FULL light being illuminated. 1

2 TANK WATER LEVEL INIDICATOR Figure 2: Image of indicator light on water recirculator 4. Verify that the flow meters on the front of the water recirculator are all above the minimum set points: X ray Target: 3.2 gpm TMP (Turbo Pump): 16 gph X ray Tube: 1.6 gpm If the readings of the flow meters are below the minimum set points, please contact a Shared Research Facilities staff member for assistance. 5. Locate the inlet and outlet pressure gauges behind the water recirculator. Read the values of each gauge and calculate the differential pressure. Record this value in the log book. WARNING: If the differential pressure is less than 16 psi, please contact a Shared Research Facilities staff member for assistance. Do not operate the system as damage to the tool can occur. 6. Verify that the ion gauge display on the Vacuum Controller panel has a minimum of two green lights illuminated as shown in Figure 3. Contact a Shared Facilities staff for assistance if there are fewer than two green lights illuminated. 7. Turn on the digital volt meter and record the resistance in the log book. If the resistance of the is above 150 mv, please contact a Shared Facilities staff for assistance. 2

3 Vacuum Pressure Indicator Lights Figure 3: Ion Gauge Control panel with vacuum level indicator lights illuminated 8. Check and set both shutter switches to the EXT position as shown in Figure 4. This ensures that the shutters are controlled by the external computer. Figure 4: Image of Shutter Control Panel with switches in EXT position 9. Verify that the voltage knob is set to 20 kv and the amperage knob is set to 10 ma on XG Controller panel see Figure 5 below. 10. Press the white T REV button and wait 10 seconds for the anode to spin up to speed see Figure 5 below. 3

4 TREV Button Current Control Knob Voltage Control Knob Figure 5: Image of XG Controller Panel 11. Press the white ON button to turn on the X ray generator. Verify that the X ray FOCUS NORMAL light is illuminated and that the voltage and the current gauges are reading 20 kv / 10 ma, respectively see Figure On the tool, check that the aluminum filter is in place in front of the high angle detector see Figure 6. Aluminum Filter Figure 6: Image of High Angle detector with filter in place WARNING: This is needed to prevent saturation and damage to the detector during the alignment process. 13. Turn on the corresponding detectors for the X ray scans to be conducted by pressing the toggle POWER button to ON and then the HV switch to see Figure 7 and 8 respectively. 4

5 For High Angle Scans: High Angle Detector and High Angle Reference Detector HV Switch POWER Button Figure 7: Image of High Angle Detectors with power and HV in the ON positions For Low Angle Scans: Low Angle Detector ONLY Figure 8: Image of Low Angle Detector with power and HV in the ON positions 14. Verify that the RED SAFETY light on the window is illuminated when the doors are closed before using the tool. If the doors are not closed properly before operating the tool, the system safety interlock will fail and the shutters will not open. Contact a Shared Research Facilities staff if the RED SAFETY light is off while the door is closed or the X ray generator is operating 15. Wait a minimum of ten minutes before conducting any scans to allow the optics to warm. This is to protect the lifetime of the detectors. 5

6 POWDER SAMPLE PREP 1. On a zero reflective piece of fused silica, apply a very thin layer of vacuum grease see Figures 9 and 10. Figure 9 and 10: Application of a thin layer of vacuum grease to the zero reflective fused silica pie ce. 2. Over a piece of weighing paper, slowly pour the powder over the fused silica. Then turn the fused silica upside down to remove any excess powder. Repeat this process until a thin layer of powder has adhered to the fused silica see Figures 11 and 12. Figure 11 and 12: Application of powder to zero reflective fused silica piece. 6

7 3. Remove excess material from edge of fused silica. The sample is now ready to be loaded into the system see Figures 13 and 14. Figure 13 and 14: Removal of sample excess from edge of zero reflective fused silica piece and final result. 4. Attach adhesive to the goniometer using the red sticky tabs and firmly and evenly press the sample dwon on top of the goniometer see figure 15 below. 5. Adjust the goniometer positions to zero using the goniometer screws. If they do not move easily, STOP and ensure that the set positions are not tightened never force the screws to move. Figure 15: Sample attached to the goniometer 7

8 POWDER SAMPLE ALIGNMENT 1. On the computer desktop open the High Angle lab view program see Figure 16 below. The Home screen is divided into three sections: Figure 16: High Angle home screen. Inputs: Allows the user to input scan type, range, increments for system scans Move Angle: The user can select one of the four drives (Theta, 2 Theta, Phi, Chi) and move the desired drive to a particular angle. This function is used during alignment and for returning drives to the home position when shutting the system down after use. Zero and Reset: This is used during alignment for entering the offset values. 2. Select the White Arrow on the toolbar to activate the system software. The arrow will change to a Black Arrow. 3. Move Θ and 2Θ to zero. This is done by selecting Θ in the Move Angle section, enter a value of zero, and then select the Move icon. Once the Θ drive has stopped moving, select Θ in the Zero and Reset section and select the Zero icon. Repeat this process for 2Θ. 4. Run a 2Θ scan with the following settings: Scan Type: 2Θ Final Angle: 2 Data Interval: 0.1 Θ Initial: 0 2Θ Initial: 2 Count Time: 1.0 s Phi Initial: 0 Chi Initial: 0 8

9 Select SCAN and then select REPLACE in the processing window. If you do not see a peak, check that the detectors are on and then repeat the scan with a date interval of 4 to 4. If this does not correct the problem, then contact a Shared Research Facilities staff member. 5. Once the scan is complete, open ORIGIN 7.5 software (this can be found on the Desktop). 6. In Origin, select File New Project. Then press CTRL+K and select the tempxr.dat file which contains the scan data. 7. Highlight the values in the C(Y) column which are your data values and press the plot icon. 8. Select Analysis Fit Gaussian. Record the Height and Center Offset values. NOTE: If the location of center is less than then proceed to step# 9 9. Return to the High Angle program. In the Move Angle section, select 2Θ from the drop down menu, enter the offset from center value, and then select MOVE. NOTE: The center offset value needs to be a multiple of If the offset is <1, then add 1 to the value and select MOVE. This will move the drive to the offset value plus one degree. Then enter the offset value and select MOVE. This will move the drive to the desired value. For example, if the offset is 0.075, first move to angle and then MOVE to This is necessary to prevent backlash in the system. 10. Repeat steps 4 until the Center Offset is less than Once the 2Θ offset is complete, enter the radiation enclosure. 12. Verify that the shutter is closed before placing your hands in the potential path of the X ray. If the shutter is open, set the shutter toggle switches to CLOSE. 13. Mount the sample goniometer to the goniometer chuck see Figure 17 below. Figure 17: Image of goniometer being attached to chuck. 14. Manually adjust the z position of the goniometer downwards by turning the z knob clockwise until the knob fails to turn see Figure 18. 9

10 Figure 18: Image of adjustment of z position. 15. Leave the radiation enclosure and enter the following Input values in the software program and select SCAN: Scan Type: Θ Final Angle: 2 Data Interval: 0.0 Θ Initial: 0 2Θ Initial: 0 Count Time: 1.0 s Phi Initial: 0 Chi Initial: Move the pop up Scan Graph window to the monitor inside the radiation enclosure. 17. Enter the radiation enclosure. Leave the entry door into the radiation enclosure open as this prevents the shutters from being controlled by the external computer. Next, change the shutter toggle switch position to OPEN. 18. Manually adjust the z position upwards so that the sample is halfway into the path beam. This is done by turning the z knob (see Figure 19) counter clockwise until the counts are half of the counts observed in the previous 2Θ (see Figure 20). 19. Reset the shutter toggle switch position to EXT and exit the radiation enclosure. 10

11 Figure 19: Using the z knob to adjust the position of the sample to half way into the x ray beam Figure 20: Screenshot of adjustment of z position 20. Move the pop up window back to the outside computer screen and select STOP. 21. Run a Θ scan by entering the following values in the input section: Scan Type: Θ Final Angle: 4 Data Interval: 0.1 Θ Initial: 4 2Θ Initial: 0 Count Time: 1.0 s Phi Initial: 0 Chi Initial: 90 Then select SCAN and REPLACE in the processing window. 22. Once the scan is complete, open ORIGIN 7.5 software (this can be found on the Desktop). 11

12 23. In Origin, select File New Worksheet. Then press CTRL+K and select the tempxr.dat file which contains the scan data. 24. Highlight the values in the C(Y) column which are your data values and press the plot icon. 25. Select Analysis Fit Gaussian. Record the Height and Center. 26. Return to the High Angle program. In the Move Angle section, select Θ from the drop down menu, enter the offset from center value and select MOVE. NOTE: The center offset value needs to be a multiple of If the offset is <1, then add 1 to the value and select MOVE. This will move the drive to the offset value plus one degree. Then enter the offset value and select MOVE. This will move the drive to the desired value. For example, if the offset is 0.075, first move to angle and then MOVE to This is necessary to prevent backlash in the system. 27. Repeat steps until the Center Offset is less than Repeat steps until the Height (counts) observed are half of the 2Θ value. 29. Once this is complete, the alignment is complete and it is time to increase the power of the generator to the desired settings. NOTE: The maximum power of the tool is 50 kv and 200 ma. 30. Increase the voltage and amperage using the following increments NOTE: Observe the DVM while slowly increasing the power so as to not allow the DVM to read above 200 mv. These settings are recommendations and are contingent upon the pressure not increasing above 200 mv. If the pressure nears 200mV, do not increase the voltage or amperage further until the pressure recovers. Also always increase the voltage before the amperage: 20 kv / 10mA 30 kv / 100 ma wait a minimum of 10 minutes 30kV / 100 ma40 kv / 160 ma wait a minimum of 10 minutes 40kV / 160 ma 40 kv / 200 ma wait a minimum of 10 minutes 40kV / 200 ma 50 kv / 200 ma wait a minimum of 10 minutes 31. Remove the aluminum filter from the detector and verify that the shutters switches are in the EXT position. 32. Enter the following values in the INPUTS sections: Scan Type: Θ 2Θ Final Angle: User Defined (<100 ) Data Interval: User Defined (> ) Θ Initial: User Defined (<50 ) 2Θ Initial: 2 times the value of Θ Initial Count Time: User Defined Phi Initial: 0 12

13 Chi Initial: 90 Then select SCAN and then Replace in the Processing window. 33. Once the scan is complete, open ORIGIN 7.5 software (this can be found on the Desktop). 34. In Origin, select File New Worksheet. Then press CTRL+K and select the tempxr.dat file which contains the scan data. 35. Highlight the values in the C(Y) column which are your data values and press the plot icon. Save DATA in appropriate USER FOLDER. 36. Proceed to Shut Down section below to return the tool to idle state. 13

14 SHUT DOWN 1. Move all the drives back to zero one at a time by selecting the drive from the drop down menu in the MOVE ANGLE section, enter a value of zero, and select MOVE. 2. On the X ray generator, reduce the power by following the sequence below: 50 kv / 200mA 40 kv / 200 ma wait a minimum of 10 seconds 40kV / 200 ma 40 kv / 160 ma wait a minimum of 10 seconds 40kV / 160 ma 30 kv / 100 ma wait a minimum of 10 seconds 30kV / 100 ma 20 kv / 10 ma these are the minimum values 3. Turn off the X ray generator by pressing the RED OFF button and listening for the rotating anode to spindown. 4. Remove sample holder goniometer from the tool. Gently remove sample from goniometer and clean adhesive from the sample holder using IPA and an alpha wipe. Dispose of all contaminated alpha wipes in the white contaminated wipes container. 5. Clean up the work area by doing the following: a. Clean the zero reflective piece of fused silica with IPA if it was used b. Place all tools into the appropriate storage containers c. Properly dispose any used materials i.e. alpha wipes, glass slides, etc. d. Return radiation monitoring badge to storage location 6. Log off the session on the FOM. Sign out in the log book. Report any problems in the comment section on the FOM and the log book. WARNING: If the powder has fallen off of your sample onto the system, a Shared Research Facilities staff member MUST be notified so that it can be properly cleaned. 14

15 EMERGENCY PROCEDURES If no one is available and the machine is not acting as expected, the user should do the following: Press STOP in Labview software. Set the voltage to 20kV and 5mA. Do not leave the machine running in an abnormal state. If the machine cannot be placed in the default state, immediately contact: Primary Staff Contact: Harley Hart (412) or Secondary Staff Contact: Dr. Weiqiang Ding (304) or The user should then complete a Tool Issue Report form and submit this form to room 409 of White Hall. The user should also add comment using the FOM software as to tool status. Then, if possible, the user should stay by the tool while trying to contact a Shared Facilities staff member. If it becomes necessary to leave the tool then the user should leave a large, legible note at the XRD stating the tool is DOWN. If a dangerous situation is evident (smoke, fire, sparks, etc.), ONLY if it is safe to do so, the user should turn off the power the x ray source by turning pressing the RED off button on the XG Controller. The user should turn off the pumps to the system by moving the pump toggle switches to the OFF positions. The user should then move the switch the breaker box at the back of the tool into the OFF position. The user should then notify all other lab persons within the White Hall 402 to evacuate and leave the lab immediately. The user should then contact proper emergency personnel from a safe place. Harley Hart Weiqiang Ding (412) (cell) (304) (cell) 15