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Hi my name is Mohammad Mayy I’m at Norfolk State University and today I’m going to
explain to you the thermal deposition machine. This is the Auto 306 thermal evaporation deposition
that we use to deposit various types of metals unto our desired substrate.
Here we have the external part that is composed of the electrical part and the assembly part.
And on the side we have the chiller which is used to cool down the internal pump.
Here we have the digital part of the instrument. This is the main switch. This the rotary for
the substrate This is main displays that we use to verify
various numbers and pressure levels. Here we have the electronic part that is required
to melt the material on to the substrate This *** is to control the current flow.
This is to visually see the amps. This is to control which side we are using,
the LT or HT This *** is to control which of the four
stations that we use. Currently we going to use station A
Here we have the thickness monitor. Here we have the mechanical part of the thermal
deposition. Here we have station A which we are going
to use to deposit our material. Our material is silver inside this boat.
Here we have our thickness measurement device that measures the thickness of the material
as we deposit. Here we have our internal shield that we use
to shield the materials from the substrate until we need it to get deposited and then
we open it and let it deposit. This is the boat that we are going to use
to hold our material and then when it heats up the material will melt depositing on the
substrate of our choice. Now we place our boat with our desired material
in this part of the instrument. And as you see I place it between these two
washers Using an Allen key size 4 millimeter you can
screw down and secure the boat During our deposition the current will flow
from this post to this post through the boat and it will heat up the silver allowing it
to deposit on the substrate. And then it will continue the circuit going to the other side.
Between this post and this piece of metal we have a ceramic that prevents it from having
a short circuit. Here we have our substrate that we are going
deposit the silver on. Our substrate is a glass piece of slide held in by a double-
sided foam tape into the cover slide holder. And we attach the slide holder into this arm
by gently placing it inside and rotating as such.
Then we can gently align this arm on top of the substrate to the height that we desire,
and then we replace the shield and it’s ready
This is our bell jar that we use to shield our sample and what it does is to help to
create the vacuum for our sample during the thermal deposition.
Then we use this external shield implosion device and place it on top of the bell jar
to protect us from an accident that might occur.
To operate our thermal deposition instrument we first turn on our main power switch from
zero to one. Then we press the” reset” button and then the “start” button.
Keeping in mind that we have to turn on the chiller at the same time
Now what’s going on - the internal pump is being warmed up getting ready for our thermal
deposition. This procedure will take about 25 to 30 minutes
Once the pump is ready the cycle display light will light up.
Now when the instrument is ready the word “sealed” will be displayed.
And you can see the LED light on the cycle button has been lighted up.
Notice that here you have the numbers 1.0 +3 MB this means one time tens to power of
plus three millibar. This is the atmospheric pressure of the room which means that the
sample is still at atmospheric pressure. To start we click cycle, and we observe the
roughing pump is being turned on and then can we observe the vacuum is roughing.
After a certain pressure the roughing pump will turn off and the fine pump will turn
on allowing a better vacuum inside the chamber. We let the vacuum run until we approach 5
x 10 to the minus 6 millibar. At this vacuum we can have an excellent deposition of material
onto our substrate. To deposit our material on to our substrate
we turn this *** to LT and turn this *** slowly and you can see the amp is changing.
For silver we point it to approximately 3.4 Amps to 3.7 amps.
As we continue to roll the *** and the amps increase we can observe the change in the
boat. The boat will slowly get hot and the until we get the desired melting temperature
When the material is melted we can move the shield aside and allow the material to deposit
on the substrate. We wait until we get our desired thickness
on the substrate and then we can gently close the shield.
Now we turn the current *** all the way back to zero and we turn the station *** from
LT to zero again. Now we press “vent” and we can observe
the pressure rapidly increasing from vacuum to room atmosphere pressure.
Now we can remove our external implosion shield. Our bell jar we can gently remove making sure
it’s back to atmospheric pressure. And now we can remove our substrate and we
can observe the metal has been deposited on our glass slide
Now you can see our clear slide before deposition and our deposited slide with the silver on
top of it. This is our boat with the material inside
after the material has been melted. To turn off the instrument first we press
"stop“ and observe that the diffusion pump has been turned off and then we turn off the
main power supply.