Temescal e-beam evaporator
Step 0: Register
Register the time you plan to use for your deposition in our equipment schedule. The typical time you need is about 1.5 hours. For multiple target deposition or extra low pressures you need 2-3 hours.
Step 1: Sample loading
- First vent the system by pressing the button 'auto stop' located under the pressure meter panel. The cryopump valve closes which can be seen on the picture with the LED's next to this button.
- Toggle the switch named vent from the 'man vent' to the 'auto' position to vent the system with nitrogen gas. You can see this valve switching again on the Temescal picture with the LED's. When the upper pressure meter reaches 1.0*103 mbar you can open the system. Return to 'man vent'.
- Check whether you need to change any material in the logbook and do so if required. Check the log to which pocket your material was loaded before and load it only in that pocket. Off course write in the log what material you changed and what is the current configuration.
- Put your sample under 1 of the clamps on the sample holder which should be located inside the plastic box near the temescal. Make sure the top cover with the clamps is properly fixed to the bottom part. Be gentle to the clamps, do not destroy them
- Fix your sample holder to the holder inside the Temescal chamber. Make sure you put it under a 0 degree tilt angle, check by looking from the side and adjust with the big micrometer on top if necessary. For shadow evaporation, set the angle on the rotation controller as well.
- Close the Nitrogen flow by toggling the vent switch from 'man vent' to 'auto' and press 'auto start'. The chamber will now first pump the system with the rough pump to 10-2 mbar after which it opens the high vacuum valve which you can monitor on the pressure meters/Temescal picture.
- You may start deposition when the pressure reaches below ~5*10-6 mbar which takes 30 minutes-1 hour. The longer you wait the lower the base pressure, the cleaner your material evaporation. Do note that the cleanliness also (probably more strongly) depends on your deposition rate.
Step 2: Deposition
- First note the base pressure you reached prior to deposition in the logbook.
- Rotate to the correct pocket for your deposition by toggling the switch located under the blue screen on the top part of the temescal. The LED indicates which pocket is located under the electron beam. If it blinks it is stuck and you have a problem :)
- On the blue screen press back until you see no change and enter the top left menu. Navigate to the third menu and press 'change' to change the material to the one you need (1-9) by looking at the card located on the right wall. Next, press 'enter' to confirm and press 'enter' again to enter this menu and check the values (density etc.) with the one needed for your material on the other list located on the right wall. Change the layer thickness to the thickness you require.
- Press back until you are at the main screen and enter 'monitor mode' which switches the first shutter allowing you to monitor the thickness.
- Switch on the red HV button located on the right part of the HV supply on top of the pressure meters.
- Turn the key switch.
- Press the red 'HV on' button.
- Press the red 'Current on' button.
- Slowly (30 sec) turn up the current with the rotary button. After a while you should see the emission current meter go up a little after which you stop.
- Position the beam nicely on your target with the controller on a phone string by looking inside the temescal through the window. Open the window to see through and immediately close to prevent too much material from evaporating on the window. You can switch between the X and Y direction on the board which is attached to the controller. Don't use a too high frequency (5-10 Hz is common) or too low frequency or you'll get a nice explosion of material in your chamber which you have to clean (as well as bring cake). The spot should be around 1 cm in size.
- Now turn up the the current even more to obtain a decent deposition rate which you should be able to see on the blue screen. It is usefull to know the previous setting which can be found in the logbook. Monitor the pressure while doing this, it should not go above ~1*10-5.
- Once you have reached a stable deposition rate (a minute or so) press 'run' to open the deposition valve. It automatically closes when the target thickness is reached. Often you start with a slow rate which you turn up a bit during deposition.
- When done turn down the current completely with the rotary switch and switch off in reverse order (current off, HV off, turn key switch, toggle big HV button).
- Note the settings you used in the logbook.
- For depositing another material wait 5 minutes before changing the pocket after which you repeat this procedure. For shadow deposition, rotate and mind the angle.
Step 3: Unload your sample
- After your last deposition wait ~5 minutes to cool down the targets.
- Vent the system again by pressing the button 'auto stop'.
- Toggle the switch named vent from the 'man vent' to the 'auto' position to vent the system with nitrogen gas. When the upper pressure meter reaches 1.0*103 mbar you can open the system. Return to 'man vent'.
- Take out your sample and put the sample holder back.
- Pump the system by toggling the vent switch again and pressing 'auto start'
|Laatst gewijzigd:||09 juli 2015 10:59|