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KJL (Old)

KJL Sputter is one of the methods to do Physical Vapor Deposition (PVD). To my knowledge, there are mainly two ways to do PVD in the cleanroom: evaporator and sputter.

schematic of the KJL sputter
rotating wafer holder
guns & targets of the KJL sputter
  1. loading smaple
  • close the vacuum valve
  • turn off “Turbo Pump”
  • wait for 1 min. (this is to protect turbo pump)
  • open N2 gas valve slowly to vent the loadlock
the N2 valve is closed
the N2 gas valve is open
  • leave the loadlock latch open. The loadlock latch will open automatically when N2 gas is full inside the loading chamber.
  • close the N2 gas valve
  • load the wafer to the holder (Groove towards “upside”)
  • close the loadlock latch
  • check whether “backing pump” is working or not. If not, turn on the “backing pump” first.
  • check whether “turbo pump” is turned off. It should be “zero” before opening “vacuum valve”.
  • open the “vacuum valve”.
  • When the pressure reaches to 2.5e-1 Torr, turn on “turbo pump”.
    (Xiaoyu don’t put too much detailed information; Yoonho explains detailed information. Please refer to Yoonho’s notes if you want to know detailed information.)

2.Transferring sample

  • When the pressure reaches to 6.0e-6 Torr, open the “Gate Valve”.
  • Push inside the wafer docking port using a loading bar
  • Pull out the wafer docking port using a loading bar
  • close the “Gate Valve”

3.Initiate Plasma – pre-sputtering process (Ti)

  • close the throttle valve until it touches screw knob
    • rotate screw gauage to indicate ~9 grade
Throttle valve fully open VS. Throttle valve fairly closed
  • turn up the Ar gas knob
  • wait until the gas rate is stabilized
  • check the MFC display and Modify the gas flow rate
    • If you want to set the gas flow rate, then move “READOUT SELECT” knob to “SET” and Change the value and Move the knob to “READ”
  • Turn the “PLANETARY CONTROL” On and Set the “Speed” as 20 rpm (Rotate your sample) (display value : 20)
  • Maintain the chamber pressure around from 25 ~ 30mTorr
  • Turn on the “POWER” and Turn on “OUPUT” on the “Power Supply”
  • Increase the power up to “150W” using “LEVEL” knob
    • When the power doesn`t go up even though you rotate “LEVEL” knob, then
    • Increase the gas flow rate from 50 to 90 sccm
    • Increase the gas flow rate from 50 to 90 sccm
  • Decrease the chamber pressure to 7.8mTorr by Rotating screw gauage ~7.6

4.Main sputtering process (Ti)

  • Increase the power up to 300W using “LEVEL” knob for Ti deposition 
  • Set time using your personal timer 
  • Open the shutter and Start your personal timer
    • * 2min deposition yields 28nm Ti layer (Deposition rate : 14nm/min) 
  • After deposition, Close the shutter – Decrease the power to 0W 
  • Turn off the “OUTPUT” and Turn off the “POWER” on the “Power Supply” 
  • Turn the gas knob “Down” position
  • Open the throttle value fully –
  • Wait for 2min

5.Pre-sputtering process (Pt)

  • Close the throttle valve until it touches screw knob
  • Rotate screw gauage to indicate ~9 grade
  • Turn the gas knob “Up” position
  • Wait until the gas rate is stabilized
  • Maintain the chamber pressure around 30mTorr
  • Turn on “POWER” on the Tunner
  • Turn on “POWER”
  • Turn on “RF ON”
  • Increase power level to “50W”
  • Open shutter for 1s and Close the shutter to make sure initiating plasma
  • Increase the power level to “150W”
  • Decrease the chamber pressure to 7.8mTorr by Rotating screw gauage ~7.6

6.main-sputtering process (Pt)

  • Increase the power up to 300W using “LEVEL” knob for Pt deposition
  • Set time using your personal timer
  • Open the shutter and Start your personal timer
    • 4min 30s deposition yields 100nm Pt layer
  • After deposition, Close the shutter
  • Decrease the power to 0W
  • Turn off the “RF ON” and Turn off the “POWER”
  • Turn the gas knob “Down” position
  • Turn the “PLANETARY CONTROL” Off
  • Open the throttle value fully
  • Wait for 2min

7.transferring sample

  • Open the “Gate Valve”
  • Push inside the wafer docking port using a loading bar (Groove should be towards “downside”)
  • Unload the wafter docking port from the rail in the main chamber
  • Pull out the wafer docking port using a loading bar
  • Close the “Gate Valve”

8.unloading sample

  • Close the “Vacuum valve”
  • Turn off “Turbo Pump”
  • Wait for 1min
  • Open the N2 gas valve slowly to vent the loadlock
  • Loadlock will automatically be open
  • Close the N2gas valve
  • Unload your sample from that wafer docking port
  • Close the Loadlock latch
  • Check whether “Turbo pump” is turned off (It should be “zero” before opening “Vacuum valve”)
  • Open the “Vacuum valve”
  • Turn on “Turbo pump” when pressure reaches to 2.5e-1 Torr

You can leave now 🙂

Chamber opening

  1. Hi-Vac Valve off
  2. Chamber Vent Valve on
  3. When the ATM is on, turn off Chamber vent valve off
  4. Hoist “up”

Chamber closing

  1. Hoist “down”
  2. Rough valve on
  3. When the chamber process reaches to 50mTorr, turn off Rough valve
  4. Turn on Hi-Vac valve

Trouble shooting

  • RF power supply case
    1. If the Forward power directly goes up high and fluctuate? -> Check your power knob was all the way to 0.
  • the main chamber pressure cannot go down to 30 mTorr
    • double check the “CRYO PUMP” is on
    • double check the “HI-VAC” is on
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