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[[Specific Process Knowledge/Lithography/Descum/PlasmaAsher1|Information about decommissioned tool can be found here.]]
[[Specific Process Knowledge/Lithography/Descum/PlasmaAsher1|Information about decommissioned tool can be found here.]]
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=Plasma Asher 2=
=Plasma Asher 2=
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[[Specific Process Knowledge/Lithography/Descum/PlasmaAsher2|Information about decommissioned tool can be found here.]]
[[Specific Process Knowledge/Lithography/Descum/PlasmaAsher2|Information about decommissioned tool can be found here.]]
<br clear="all" />


=Plasma Asher 3: Descum=
=Plasma Asher 3: Descum=
Product name: Diener Pico Plasma Asher<br>
Year of purchase: 2014
The user manual(s), quality control procedure(s) and results and contact information can be found in [http://labmanager.dtu.dk/function.php?module=Machine&view=view&mach=423 LabManager] - '''requires login'''
The user manual(s), quality control procedure(s) and results and contact information can be found in [http://labmanager.dtu.dk/function.php?module=Machine&view=view&mach=423 LabManager] - '''requires login'''


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The plasma asher is equipped with 2 gaslines: oxygen and nitrogen, but all standard processes use only oxygen (as recommended by Diener).
The plasma asher is equipped with 2 gaslines: oxygen and nitrogen, but all standard processes use only oxygen (as recommended by Diener).


'''Process parameters'''<br>
You can manipulate two different descum process development parameters: you can either change power or chamber pressure.


'''Ashing of  AZ MiR701 resist:'''<br>
==Power testing - AZ MiR 701==
You can use two different descum process developments: you can either change power settings or processing chamber pressure.
[[image:AZMIR701_power_settings.png|400px|thumb|Descum results for different power settings]]
 
 
'''Testing different power settings:'''
[[image:AZMIR701_power_settings.png|640px|thumb|Descum results for different power settings]]


'''Recipe settings:'''
'''Recipe settings:'''
*Resist: AZ MiR 701
*O2 flow: 5 sccm
*O2 flow: 5 sccm
*N2 flow: 0
*N2 flow: 0
Line 38: Line 42:
*Power: Varied
*Power: Varied


 
{| class="wikitable" style="text-align: center;"
'''Experiment parameters:'''
|+ style="caption-side: top; text-align: left;" | Experiment parameters
{| {{table}}
|-
| align="center" |
!  !! Forward/reverse !! C2/C1 !! Power
{|border="1" cellspacing="1" cellpadding="10" style="text-align:left;"  
|- style="background:LightGrey"
| ||FW/REV|| C2/C1 || Power
|-
|'''recipe 1''' || 50/0 || 52/31 || 50%
|-
|-
|'''recipe 2''' || 100/0 || 53/31 || 100%
| style="text-align: left;" | '''recipe 1''' || 50/0 || 52/31 || 50%
|-
|-
|'''recipe 3''' || 20/0 || 51/34 || 20%
| style="text-align: left;" | '''recipe 2''' || 100/0 || 53/31 || 100%
|-
|-
| style="text-align: left;" | '''recipe 3''' || 20/0 || 51/34 || 20%
|}
|}
|}
<br clear="all" />


'''Testing different pressure settings:'''
==Pressure testing - AZ MiR 701==
[[image:AZMIR701_pressure_settings.png|640px|thumb|Descum results for different pressure settings]]
[[image:AZMIR701_pressure_settings.png|400px|thumb|Descum results for different pressure settings]]


'''Recipe settings:'''
'''Recipe settings:'''
*Resist: AZ MiR 701
*O2 flow: varied
*O2 flow: varied
*N2 flow: 0
*N2 flow: 0
Line 66: Line 64:
*Power: V100% (100 W)
*Power: V100% (100 W)


 
{| class="wikitable" style="text-align: center;"
'''Experiment parameters:'''
|+ style="caption-side: top; text-align: left;" | Experiment parameters
{| {{table}}
|-
| align="center" |
!  !! Forward/reverse !! C2/C1 !! Oxygen !! Pressure
{|border="1" cellspacing="1" cellpadding="10" style="text-align:left;"  
|- style="background:LightGrey"
| ||FW/REV|| C2/C1 || Oxygen || Pressure
|-
|'''recipe 1'''|| 100/0 || 53/31 || 5 || 0,2
|-
|-
|'''recipe 2''' || 100/0 || 37/38 || 45 || 0,8
| style="text-align: left;" | '''recipe 1''' || 100/0 || 52/31 || 5 || 0.2
|-
|-
| style="text-align: left;" | '''recipe 2''' || 100/0 || 37/38 || 45 || 0.8
|}
|}
|}
<br clear="all" />
'''Ashing of AZ5214E resist:'''
[[image:AZ5214E_pressure_settings.png|640px|thumb|Descum results for different pressure settings]]


==Pressure testing - AZ 5214E==
[[image:AZ5214E_pressure_settings.png|400px|thumb|Descum results for different pressure settings]]


'''Recipe settings:'''
'''Recipe settings:'''
*Resist: AZ 5214E
*O2 flow: varied
*O2 flow: varied
*N2 flow: 0
*N2 flow: 0
Line 92: Line 84:
*Power: V100% (100 W)
*Power: V100% (100 W)


 
{| class="wikitable" style="text-align: center;"
'''Experiment parameters:'''
|+ style="caption-side: top; text-align: left;" | Experiment parameters
{| {{table}}
|-
| align="center" |
!  !! Forward/reverse !! C2/C1 !! Oxygen !! Pressure
{|border="1" cellspacing="1" cellpadding="10" style="text-align:left;"  
|- style="background:LightGrey"
| ||FW/REV|| C2/C1 || Oxygen || Pressure
|-
|'''recipe 1'''|| 100/0 || 53/31 || 17 || 0,4
|-
|-
|'''recipe 2''' || 100/0 || 37/39 || 45 || 0,8
| style="text-align: left;" | '''recipe 1''' || 100/0 || 52/31 || 17 || 0.4
|-
|-
| style="text-align: left;" | '''recipe 2''' || 100/0 || 37/39 || 45 || 0.8
|}
|}
|}
 
<br clear="all" />
<br clear="all" />


=Plasma Asher 4=
=Plasma Asher 4=
==Descum processing in plasma asher 4 & 5==
Product name: PVA Tepla Gigabatch 380M<br>
Descum of AZ 5214E on 100 mm wafers. The descum process was tested for single substrates, as well as 3 substrates, placed vertically in the glass boat. For the 3 substrates only the center substrate was used for testing, the front and back wafers were used as dummy wafers.<br>
Year of purchase: 2024
 
Descum of AZ 5214E on 100 mm wafers. The descum process development was done for a single substrate, as well as 3 substrates (for decreased ashing rate and improved ashing uniformity). The substrates were placed vertically in the glass boat.
 
<gallery style="text-align: center;" widths=250 heights=250>
PA_boat_1Wafer_v2.png|Single vertical substrate
PA_boat_3Wafer_v2.png|3 vertical substrates:<br>Dummy - Test - Dummy
</gallery>


When running multiple wafers, the first and last wafers should always be dummy wafers.
For the 3 substrates only the center substrate was used for testing, the front and back wafers were used as dummy wafers. The wafers were placed in consecutive slots - when running multiple wafers in this way, the first and last wafers should always be dummy wafers.


The user manual, risk assessment, and contact information can be found in [http://labmanager.dtu.dk/function.php?module=Machine&view=view&mach=530 LabManager] - '''requires login'''
The user manual, risk assessment, and contact information can be found in [http://labmanager.dtu.dk/function.php?module=Machine&view=view&mach=530 LabManager] - '''requires login'''


'''Typical descum parameters'''
'''Typical descum parameters'''<br>
Tested with 1.5 µm AZ 5214E on 100 mm silicon substrate.
*O<sub>2</sub>: 100 sccm
*O<sub>2</sub>: 100 sccm
*N<sub>2</sub>: 100 sccm
*N<sub>2</sub>: 100 sccm
*Pressure (DSC): 1.3 mbar
*Pressure (DSC): 1.3 mbar
*Power: 200 W
*Power: 200 W
*Chamber temperature at start: 30°C
*Chamber temperature at start (with door closed): 30°C
*Time (single wafer): 5-10 minutes = 35-72 nm ashed
*Time (single wafer): 5-10 minutes = 35-72 nm ashed
*Time (multiple wafers): 10-15 minutes = 40-80 nm ashed
*Time (multiple wafers): 10-15 minutes = 40-80 nm ashed
Line 127: Line 123:
{| class="wikitable"
{| class="wikitable"
|-
|-
! Test setup !! Single substrate !! Center of 3 substrates
! !! Single substrate !! Center of 3 substrates
|-
! scope=row style="text-align: left;" | Test results: ashing rate
| 5.7 ±2.1 nm/min|| 3.8 ±1.6 nm/min
|-
|-
! scope=row| Test results
! scope=row style="text-align: left;" | Test results: non-uniformity
| Ashing rate: 5.7 ±2.1 nm/min<br>Non-uniformity: 0.6 ±0.4% || Ashing rate: 3.8 ±1.6 nm/min<br>Non-uniformity: 0.4 ±0.2%
| 0.6 ±0.4% || 0.4 ±0.2%
|-
|-
! scope=row| Wafers  
! scope=row style="text-align: left;" | Wafers  
| 1 || 3  
| 1 || 3  
|-
|-
! scope=row| Wafer size
! scope=row style="text-align: left;" | Wafer size
| 100 mm || 100 mm  
| 100 mm || 100 mm  
|-
|-
! scope=row| Boat position
! scope=row style="text-align: left;" | Boat position
| Center of chamber || Center of chamber  
| Center of chamber || Center of chamber  
|-
|-
! scope=row| Test wafer position
! scope=row style="text-align: left;" | Test wafer position
| Center of boat || Center of boat  
| Center of boat || Center of boat  
|-
|-
! scope=row| Total gas flow rate
! scope=row style="text-align: left;" | Total gas flow rate
| 200 sccm || 200 sccm
| 200 sccm || 200 sccm
|-
|-
! scope=row| Gas mix ratio
! scope=row style="text-align: left;" | Gas mix ratio
| 50% N<sub>2</sub> || 50% N<sub>2</sub>
| 50% N<sub>2</sub> || 50% N<sub>2</sub>
|-
|-
! scope=row| Chamber pressure
! scope=row style="text-align: left;" | Chamber pressure
| 1.3 mbar || 1.3 mbar
| 1.3 mbar || 1.3 mbar
|-
|-
! scope=row| Power
! scope=row style="text-align: left;" | Power
| 200 W || 200 W  
| 200 W || 200 W  
|-
|-
! scope=row| Test processing time
! scope=row style="text-align: left;" | Test processing time
| Tested parameter || Tested parameter
| Tested parameter || Tested parameter
|-
|-
! scope=row| Test average temperature
! scope=row style="text-align: left;" | Test average temperature
| 33°C || 33°C  
| 33°C || 33°C  
|}
|}


<br clear="all" />
<br clear="all" />
<hr>


==Single wafer descum ashing rate and uniformity for plasma asher 4 & 5==
[[File:PA_descum_single_v3.png|400px|thumb|Ashing amount and ashing rate when processing a single 100 mm wafer.|right]]


[[File:PA_descum_single_v2.png|400px|thumb|Ashing amount and ashing rate when processing a single 100 mm wafer.|right]]
{| class="wikitable" style="text-align: center;"
'''Single wafer ashing rate'''<br>
|+ style="caption-side: top; text-align: left;" | Ashing amount and rate
{| class="wikitable"
|-
|-
! Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
! style="text-align: left;" | Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
|-
|-
| Ashing amount [nm]: || 5.2 || 6.2 || 35.1 || 72.3 || 87.1
| style="text-align: left;" | Ashing amount [nm]: || 5.2 || 6.2 || 35.1 || 72.3 || 87.1
|-
|-
| Ashing rate [nm/min]: || 5.2 || 3.1 || 7.0 || 7.2 || 5.8
| style="text-align: left;" | Ashing rate [nm/min]: || 5.2 || 3.1 || 7.0 || 7.2 || 5.8
|}
|}


 
{| class="wikitable" style="text-align: center;"
'''Single wafer non-uniformity'''<br>
|+ style="caption-side: top; text-align: left;" | Ashing non-uniformity
{| class="wikitable"
|-
|-
! Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
! style="text-align: left;" | Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
|-
|-
| Film thickness range, before descum [nm]: || 11 || 12 || 10 || 11 || 9
| style="text-align: left;" | Pre-descum film thickness range [nm]: || 11 || 12 || 10 || 11 || 9
|-
|-
| Pre-ashing non-uniformity [%]: || 0.37 || 0.40 || 0.33 || 0.37 || 0.30
| style="text-align: left;" | Pre-descum non-uniformity [%]: || 0.37 || 0.40 || 0.33 || 0.37 || 0.30
|-
|-
| Film thickness range, after descum [nm]: || 10 || 10 || 12 || 19 || 33
| style="text-align: left;" | Post-descum film thickness range [nm]: || 10 || 10 || 12 || 19 || 33
|-
|-
| Post-ashing non-uniformity [%]: || 0.33 || 0.33 || 0.41 || 0.66 || 1.18
| style="text-align: left;" | Post-descum non-uniformity [%]: || 0.33 || 0.33 || 0.41 || 0.66 || 1.18
|}
|}


<br clear="all" />
<br clear="all" />
<hr>


==Multi wafer descum ashing rate and uniformity for plasma asher 4 & 5==
[[File:PA_descum_multi_v3.png|400px|thumb|Ashing amount and ashing rate when processing multiple 100 mm wafers. Test measured on the center of 3 wafers.|right]]


[[File:PA_descum_multi_v2.png|400px|thumb|Ashing amount and ashing rate when processing multiple 100 mm wafers. Test measured on the center of 3 wafers.|right]]
{| class="wikitable" style="text-align: center;"
'''Multi wafer ashing rate'''<br>
|+ style="caption-side: top; text-align: left;" | Ashing amount and rate
{| class="wikitable"
|-
|-
! Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
! style="text-align: left;" | Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
|-
|-
| Ashing amount [nm]: || 4.3 || 6.7 || 10.1 || 39.5 || 78.8
| style="text-align: left;" | Ashing amount [nm]: || 4.3 || 6.7 || 10.1 || 39.5 || 78.8
|-
|-
| Ashing rate [nm/min]: || 4.3 || 3.4 || 2.0 || 4.0 || 5.3
| style="text-align: left;" | Ashing rate [nm/min]: || 4.3 || 3.4 || 2.0 || 4.0 || 5.3
|}
|}


 
{| class="wikitable" style="text-align: center;"
'''Multi wafer non-uniformity'''<br>
|+ style="caption-side: top; text-align: left;" | Ashing non-uniformity
{| class="wikitable"
|-
|-
! Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
! style="text-align: left;" | Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
|-
|-
| Film thickness range, before descum [nm]: || 11 || 13 || 11 || 12 || 14
| style="text-align: left;" | Pre-descum film thickness range [nm]: || 11 || 13 || 11 || 12 || 14
|-
|-
| Pre-ashing non-uniformity [%]: || 0.37 || 0.43 || 0.37 || 0.40 || 0.46
| style="text-align: left;" | Pre-descum non-uniformity [%]: || 0.37 || 0.43 || 0.37 || 0.40 || 0.46
|-
|-
| Film thickness range, after descum [nm]: || 11 || 9 || 10 || 12 || 21
| style="text-align: left;" | Post-descum film thickness range [nm]: || 11 || 9 || 10 || 12 || 21
|-
|-
| Post-ashing non-uniformity [%]: || 0.37 || 0.30 || 0.33 || 0.41 || 0.74
| style="text-align: left;" | Post-descum non-uniformity [%]: || 0.37 || 0.30 || 0.33 || 0.41 || 0.74
|}
|}


<br clear="all" />
<br clear="all" />
<hr>


'''Comparison between single substrate processing and multi substrate processing'''<br>
==Comparison between single substrate processing and multi substrate processing for plasma asher 4 & 5==
Processing a single substrate using the standard descum settings will provide users with a relatively controllable and uniform process. Adding dummy substrates in close proximity with the process substrate will reduce the ashing rate and improve the uniformity:
Processing a single substrate using the standard descum settings will provide users with a relatively controllable and uniform process. Adding dummy substrates in close proximity with the process substrate will reduce the ashing rate and improve the uniformity:
<gallery mode="packed-hover" heights="150">
<gallery mode="packed-hover" heights="150">
Line 235: Line 231:


<br clear="all" />
<br clear="all" />
==Comparison of ashing rate between substrate sizes==
It is assumed that the low power descum rates, for different substrate sizes, follows the same pattern as the high power ashing rates, which can be seen [[Specific_Process_Knowledge/Lithography/Strip#Comparison_of_ashing_rate_between_substrate_sizes_for_plasma_asher_4_&_5|here]].


=Plasma Asher 5=
=Plasma Asher 5=
Plasma asher 5 is identical to plasma asher 4, see descum processing for plasma asher 4 [[Specific_Process_Knowledge/Lithography/Descum#Descum_processing_in_plasma_asher_4_&_5|here]].
Product name: PVA Tepla Gigabatch 380M<br>
Year of purchase: 2024
 
Plasma asher 5 is identical to plasma asher 4, see descum processing for plasma asher 4 [[Specific_Process_Knowledge/Lithography/Descum#Plasma_Asher_4|here]].

Latest revision as of 15:39, 6 March 2025

The content on this page, including all images and pictures, was created by DTU Nanolab staff, unless otherwise stated.

Feedback to this page: click here

Plasma Asher 1

Plasma asher 1 was decommissioned 2024-12-02.

Information about decommissioned tool can be found here.

Plasma Asher 2

Plasma asher 2 was decommissioned 2024-12-02.

Information about decommissioned tool can be found here.

Plasma Asher 3: Descum

Product name: Diener Pico Plasma Asher
Year of purchase: 2014

The user manual(s), quality control procedure(s) and results and contact information can be found in LabManager - requires login

Plasma Asher 3 is specifically used for controlled descum process after lithography. Please note that you only can process a single 100 mm wafer, or one small sample, at a time. The plasma asher is equipped with 2 gaslines: oxygen and nitrogen, but all standard processes use only oxygen (as recommended by Diener).

Process parameters
You can manipulate two different descum process development parameters: you can either change power or chamber pressure.

Power testing - AZ MiR 701

Descum results for different power settings

Recipe settings:

  • Resist: AZ MiR 701
  • O2 flow: 5 sccm
  • N2 flow: 0
  • Pressure: 0.2 mbar
  • Power: Varied
Experiment parameters
Forward/reverse C2/C1 Power
recipe 1 50/0 52/31 50%
recipe 2 100/0 53/31 100%
recipe 3 20/0 51/34 20%

Pressure testing - AZ MiR 701

Descum results for different pressure settings

Recipe settings:

  • Resist: AZ MiR 701
  • O2 flow: varied
  • N2 flow: 0
  • Pressure: varied
  • Power: V100% (100 W)
Experiment parameters
Forward/reverse C2/C1 Oxygen Pressure
recipe 1 100/0 52/31 5 0.2
recipe 2 100/0 37/38 45 0.8

Pressure testing - AZ 5214E

Descum results for different pressure settings

Recipe settings:

  • Resist: AZ 5214E
  • O2 flow: varied
  • N2 flow: 0
  • Pressure: varied
  • Power: V100% (100 W)
Experiment parameters
Forward/reverse C2/C1 Oxygen Pressure
recipe 1 100/0 52/31 17 0.4
recipe 2 100/0 37/39 45 0.8


Plasma Asher 4

Product name: PVA Tepla Gigabatch 380M
Year of purchase: 2024

Descum of AZ 5214E on 100 mm wafers. The descum process development was done for a single substrate, as well as 3 substrates (for decreased ashing rate and improved ashing uniformity). The substrates were placed vertically in the glass boat.

  • Single vertical substrate
    Single vertical substrate
  • 3 vertical substrates: Dummy - Test - Dummy
    3 vertical substrates:
    Dummy - Test - Dummy

For the 3 substrates only the center substrate was used for testing, the front and back wafers were used as dummy wafers. The wafers were placed in consecutive slots - when running multiple wafers in this way, the first and last wafers should always be dummy wafers.

The user manual, risk assessment, and contact information can be found in LabManager - requires login

Typical descum parameters
Tested with 1.5 µm AZ 5214E on 100 mm silicon substrate.

  • O2: 100 sccm
  • N2: 100 sccm
  • Pressure (DSC): 1.3 mbar
  • Power: 200 W
  • Chamber temperature at start (with door closed): 30°C
  • Time (single wafer): 5-10 minutes = 35-72 nm ashed
  • Time (multiple wafers): 10-15 minutes = 40-80 nm ashed
Single substrate Center of 3 substrates
Test results: ashing rate 5.7 ±2.1 nm/min 3.8 ±1.6 nm/min
Test results: non-uniformity 0.6 ±0.4% 0.4 ±0.2%
Wafers 1 3
Wafer size 100 mm 100 mm
Boat position Center of chamber Center of chamber
Test wafer position Center of boat Center of boat
Total gas flow rate 200 sccm 200 sccm
Gas mix ratio 50% N2 50% N2
Chamber pressure 1.3 mbar 1.3 mbar
Power 200 W 200 W
Test processing time Tested parameter Tested parameter
Test average temperature 33°C 33°C


Single wafer descum ashing rate and uniformity for plasma asher 4 & 5

Ashing amount and ashing rate when processing a single 100 mm wafer.
Ashing amount and rate
Ashing time [min]: 1 2 5 10 15
Ashing amount [nm]: 5.2 6.2 35.1 72.3 87.1
Ashing rate [nm/min]: 5.2 3.1 7.0 7.2 5.8
Ashing non-uniformity
Ashing time [min]: 1 2 5 10 15
Pre-descum film thickness range [nm]: 11 12 10 11 9
Pre-descum non-uniformity [%]: 0.37 0.40 0.33 0.37 0.30
Post-descum film thickness range [nm]: 10 10 12 19 33
Post-descum non-uniformity [%]: 0.33 0.33 0.41 0.66 1.18


Multi wafer descum ashing rate and uniformity for plasma asher 4 & 5

Ashing amount and ashing rate when processing multiple 100 mm wafers. Test measured on the center of 3 wafers.
Ashing amount and rate
Ashing time [min]: 1 2 5 10 15
Ashing amount [nm]: 4.3 6.7 10.1 39.5 78.8
Ashing rate [nm/min]: 4.3 3.4 2.0 4.0 5.3
Ashing non-uniformity
Ashing time [min]: 1 2 5 10 15
Pre-descum film thickness range [nm]: 11 13 11 12 14
Pre-descum non-uniformity [%]: 0.37 0.43 0.37 0.40 0.46
Post-descum film thickness range [nm]: 11 9 10 12 21
Post-descum non-uniformity [%]: 0.37 0.30 0.33 0.41 0.74


Comparison between single substrate processing and multi substrate processing for plasma asher 4 & 5

Processing a single substrate using the standard descum settings will provide users with a relatively controllable and uniform process. Adding dummy substrates in close proximity with the process substrate will reduce the ashing rate and improve the uniformity:

  • Ashing amount
    Ashing amount
  • Ashing rate
    Ashing rate
  • Non-uniformity
    Non-uniformity


Comparison of ashing rate between substrate sizes

It is assumed that the low power descum rates, for different substrate sizes, follows the same pattern as the high power ashing rates, which can be seen here.

Plasma Asher 5

Product name: PVA Tepla Gigabatch 380M
Year of purchase: 2024

Plasma asher 5 is identical to plasma asher 4, see descum processing for plasma asher 4 here.

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