Reservation  -     

Center of MicroNanoTechnology CMi

Atomic Layer Deposition BENEQ TFS200
Presentation of the equipment


ALD


I. Introduction CMI

The tool Beneq TFS200 is an ALD (Atomic Layer Deposition) system done for the deposition of thin dielectric or metallic layers on wafers from 100 mm up to 200 mm as well as on piece of wafers. The Atomic Layer Deposition (ALD) technique is recommended for thin layers (max 100 nm) and/or layers with a high level of conformality. The deposition is done under vacuum (around 5 mbar) from chemical precursors.



II. Equipment description CMI

The equipment is composed of:

 

The equipment is driven by a software interface but some manual operations are requested for each deposition:



Chamber

The reactor is designed for flat samples from dies of 1x1 cm up to wafers of 200 mm with a thikcness of 1.5 mm maximum. The reactor is equipped with a plasma source and an ozone generator. The chamber can be heat up to 500°C.




III. Deposition mechanisms CMI

The mechanism of deposition for the Atomic Layer Deposition (ALD) is composed of 4 steps as described below whatever the reactor:

1.         The first precursor (precursor 1) is pulsed into the reactor and reacts at the surface of the sample by chemisorption (steps 1.a and 1.b).

2.         The reaction chamber is purged with inert gas (N2) and the excess of precursor 1 is removed (step 2).

3.         The second precursor (precursor 2) is pulsed into the reactor and reacts with the precursor 1 already present at the surface of the sample.

            The reaction generate the desired monolayer of and a byproduct (step 3.a and 3.b).

4.         The byproduct and the excess of precursor are then purged from the reactor with inert gas (N2) (step 4).

 

The 4 steps represent the elementary loop which is repeated until we get the requested thickness of the layer. An illustration of these 4 steps is done with the deposition of Al2O3 from the Tri-Methyl Aluminum (TMA) and water (H2O).



Step 1.a
Introduction of the precursor 1 (TMA) in the reactor

Step 1.b
Chemisorption of precursor 1 (TMA) at the Si surface with radical OH

Al(CH3)3 (g) + Si-O-H (s) -> Si-O-Al(CH3)2 (s) + CH4



Step 2
Purge with N2



Step 3.a
Introduction of the precursor 2 (H2O) in the reactor
Step 3.b
Reaction of the precursor 2 (H2O) at the surface

2 H2O (g) + Si-O-Al(CH3)2 (s) -> Si-O-Al(OH)2 (s) + 2 CH4



Step 4
Formation of a mono layer of Al2O3 and purge with N2

After 3 cycles for example



IV. Available layers at CMi CMI



Precusor 1Temp. (°C)Precusor 2Temp. (°C)Chamber temperature (°C)Deposition rate (A/cy)
Al2O3TMARTH2ORT2001.22
Al2O3TMARTO3
RT2001.22
TiO2TiCl4RTH2ORT2000.42
HfO2TEMAH80H2ORT2001.0
SiO2BTBASRTO3RT3001.0
Pt
(CpMePtMe)75
O2
RT
280
0.5




How to use the system

I. Login CMI




1. Login on the PC zone  4



2. Press the button "Control" to open the window "Control" on the Beneq laptop



3. Login on Beneq laptop (if it's not already done)
  1. Login: oper
  2. Password: oper
Control screen view

Control screen view


II. Setting of the chamber and precursor temperatures CMI

On the control window, you click on the black number corresponding to the reactor temperature and to the precursor temperature and you enter the temperate requested for the deposition (see below). It takes roughly 30 min for the reactor to get 200°C from room temperature and 1 hour for the hot sources.

Al2O3
  • Chamber: 200°C
  • Liquid precursor 2 (TMA): room temperature
Control screen view

Control screen view
HfO2
  • Chamber: 200°C
  • Hot source 1 (TEMAH): 80°C
TiO2
  • Chamber: 200°C
  • Liquid precursor 3 (TiCl4): room temperature
SiO2
  • Chamber: 300°C
  • Liquid precursor 4 (BTBAS): room temperature
Pt
  • Chamber: 280°C
  • Hot source 2 (CpMePtMe): 75°C



III. Wafer loading

1. Press on the load lock button (bottom right)

2. Press on load-lock vent and wait until the load lock is at atmospheric pressure

3. Open the load-lock door

4. Load your wafer/samples

5. Close the load-lock door and press on load-lock pump down

6. Checking of the wafer position

7. Open gate valve

8. Manual transfer of the wafers in reactor with the substrate loader

9. Move up the substrate lifter

10. Move back the substrate loader in home position

11. Move down the substrate lifter

12. Move up the holder lifter

13. Close the gate valve






After 5 min, check the chamber and reactor pressure, if the pressure of the chamber pressure is below 4 mbar, the loading is not correct.
Move down and up 2 times the holder lifter.
 

If there is no improvement, unload the wafer/sample and restart the procedure.

 

DO NOT START THE DEPOSITION IF THE PRESSURE DIFFERENCE BETWEEN THE CHAMBER AND THE REACTOR IS BELOW 6 MBAR




    IV. Starting a recipe CMI


      1. Go to the window Control

      2. Select your recipe in the recipe folder

      3. Press compile and download the recipe

      4. Press start batch and follow the instructions
      (open precursor valves)

      5. At the end of the process close the hand valve if requested




        Al2O3
        Open liquid precursor 1 (H2O)
        Open liquid precursor 2 (TMA)



        Liquid precursors

        HfO2
        Open liquid precursor 1 (H2O)
        Hot source 1 is already open (TEMAH)

        TiO2
        Open liquid precursor 1 (H2O)
        Open liquid precursor 3 (TiCl4)

        SiO2
        Open liquid precursor 4 (BTBAS)
        Gas precursor (O3) is already open

        Pt: Hot source 2 is already open (CpMePtMe) / gas precursor (O2) is already open



        V. Wafer unloading CMI

          1. Go the window Load lock

          2. Open the gate valve

          3. Move down the holder lifter

          4. Move up the substrate lifter

          5. Transfer of the substrate loader in the reactor

          6. Move down the substrate lifter

          7. Move back the substrate loader in home position

          8. Close the gate valve

          9. load-lock vent / wafer unloading

          10. Open the load-lock door and take your wafers

          11. Close the load-lock door and then clic on load-lock pump down

          12. wait for the message "Load-lock vacuumize. Close load-lock lid. Press yes to continue"  and press yes

          13. wait for the message "Load-lock vacuumize. Gate valve can be opened. Press yes to continue" and press yes



            VI. logout CMI

            Once all your depositions are finished, the equipment come back in idle mode:

            1.
            Switch off the heating of the hot source

            2. Fill in the notebook

            3. Log out on the PC zone 4