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[[Category: Equipment |Lithography descum]]
[[Category: Equipment|Lithography descum]]
[[Category: Lithography|Descum]]
[[Category: Lithography|Descum]]


==Descum results==
__TOC__


===[http://labadviser.nanolab.dtu.dk/index.php/Specific_Process_Knowledge/Lithography/Strip#Plasma_asher Plasma asher 1]===
=Plasma Asher 1=
<span style="color:red">Plasma asher 1 was decommissioned 2024-12-02.</span>


[[image:Descum Results aug 2019.png|right|frame|400x400px| Descum results plasma asher 1. September 2019]]
[[Specific Process Knowledge/Lithography/Descum/PlasmaAsher1|Information about decommissioned tool can be found here.]]
<br clear="all" />


=Plasma Asher 2=
<span style="color:red">Plasma asher 2 was decommissioned 2024-12-02.</span>


Descum of AZ5214E resist on 50mm silicon wafer. Wafer was placed horisontally in chamber on a 100 mm carier wafer.
[[Specific Process Knowledge/Lithography/Descum/PlasmaAsher2|Information about decommissioned tool can be found here.]]
<br clear="all" />


Note: Plasma asher was cold before use
=Plasma Asher 3: Descum=
Product name: Diener Pico Plasma Asher<br>
Year of purchase: 2014


{| {{table}}
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'''
| align="center" |  
 
{| border="1" cellspacing="1" cellpadding="2"  align="center"
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.
! colspan="4" | Settings
The plasma asher is equipped with 2 gaslines: oxygen and nitrogen, but all standard processes use only oxygen (as recommended by Diener).
! colspan="6" | Etched Thickness (nm)
 
'''Process parameters'''<br>
You can manipulate two different descum process development parameters: you can either change power or chamber pressure.
 
==Power testing - AZ MiR 701==
[[image:AZMIR701_power_settings.png|400px|thumb|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
 
{| class="wikitable" style="text-align: center;"
|+ style="caption-side: top; text-align: left;" | Experiment parameters
|-
|-
| colspan="4" |
!  !! Forward/reverse !! C2/C1 !! Power
! colspan="6" | ashing time (min)  
|- style="background:LightGrey"
|| Recipe || O2 flow || N2 flow || Power  
| 1 || 2 || 5 || 7 || 10 || 10
|-
|-
| 1 || 70 || 70 || 150 || 14,2 || 16,3 || 47,6 || 123,2 || 854,3 || 862,1
| style="text-align: left;" | '''recipe 1''' || 50/0 || 52/31 || 50%
|-
|-
| 2 || 500 || 0 || 200 ||  || 8,1 || 32,9 || 271,1 || 495,6 || 446,2
| style="text-align: left;" | '''recipe 2''' || 100/0 || 53/31 || 100%
|-
|-
| style="text-align: left;" | '''recipe 3''' || 20/0 || 51/34 || 20%
|}
|}
|}
Conny Hjort & Jesper Hanberg
September 2019


[[image:PA1_descum.jpg|right|frame|400x400px| Different resist descum results plasma asher 1. August 2021]]
==Pressure testing - AZ MiR 701==
[[image:AZMIR701_pressure_settings.png|400px|thumb|Descum results for different pressure settings]]


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


Descum of different resists, AZ5214E, AZ701 MiR and AZ2020 nLOF, on a single 100mm wafer was tested. Wafer was placed vertically in the middle of glass carrier.
{| class="wikitable" style="text-align: center;"
Recipe setting was the same as in previous test in September 2019: 70ml/min O2, 70 ml/min N2, power 150W, different ashing time 1, 2, 3, 5 and 7 min run. Plasma Asher was cold before use, we observed minor temperature rise during processing, but not more than 5 degrees. Starting chambers pressure was around 0, 5 mbar.
|+ style="caption-side: top; text-align: left;" | Experiment parameters
 
'''1,5 um AZ5214E resist'''
{| {{table}}
| align="center" |
{| border="1" cellspacing="1" cellpadding="2"  align="center"
|- style="background:LightGrey"
|'''Ashing time (min)'''|| 1|| 2 || 3 || 5 || 7
|-
|'''Etched Thickness (nm)'''|| 6,28 || 102,99 || 76,92 || N/A || N/A
|-
|-
|}
! !! Forward/reverse !! C2/C1 !! Oxygen !! Pressure
|}
'''1,5 um AZ5214E resist placed horizontally in the carrier'''
{| {{table}}
| align="center" |
{| border="1" cellspacing="1" cellpadding="2" align="center"
|- style="background:LightGrey"
|'''Ashing time (min)'''|| 1|| 2 || 3 || 5 || 7
|-
|'''Etched Thickness (nm)'''|| 63,03 || 143,32 || 304,29  || 372,59 || N/A
|-
|-
|}
| style="text-align: left;" | '''recipe 1''' || 100/0 || 52/31 || 5 || 0.2
|}
'''1,5 um AZ701MiR resist'''
{| {{table}}
| align="center" |
{| border="1" cellspacing="1" cellpadding="2"  align="center"
|- style="background:LightGrey"
|'''Ashing time (min)'''|| 1|| 2 || 3 || 5 || 7
|-
|'''Etched Thickness (nm)'''|| 268,88 || 199,54 || 219,03 || 200,86 || 292,15
|-
|-
| style="text-align: left;" | '''recipe 2''' || 100/0 || 37/38 || 45 || 0.8
|}
|}
|}


'''1,5 um AZ 2020nLOF resist'''
==Pressure testing - AZ 5214E==
{| {{table}}
[[image:AZ5214E_pressure_settings.png|400px|thumb|Descum results for different pressure settings]]
| align="center" |
 
{| border="1" cellspacing="1" cellpadding="2"  align="center"
'''Recipe settings:'''
*Resist: AZ 5214E
|- style="background:LightGrey"
*O2 flow: varied
|'''Ashing time (min)'''|| 1|| 2 || 3 || 5 || 7
*N2 flow: 0
|-  
*Pressure: varied
|'''Etched Thickness (nm)'''|| 1,68 || 76,51 || 169,72 || 481,96 || 272,59
*Power: V100% (100 W)
 
{| class="wikitable" style="text-align: center;"
|+ style="caption-side: top; text-align: left;" | Experiment parameters
|-
!  !! Forward/reverse !! C2/C1 !! Oxygen !! Pressure
|-
|-
|}
| 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" />


=Plasma Asher 4=
Product name: PVA Tepla Gigabatch 380M<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>


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.


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


===[http://labadviser.nanolab.dtu.dk/index.php/Specific_Process_Knowledge/Lithography/Strip#Plasma_Asher_2 Plasma asher 2]===
'''Typical descum parameters'''<br>
[[image:descum_graf.jpg|right|frame|355x355px|Descum results plasma asher 2 - recipe 1]]
Tested with 1.5 µm AZ 5214E on 100 mm silicon substrate.
*O<sub>2</sub>: 100 sccm
*N<sub>2</sub>: 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


Descum of AZ  Mir 701 resist on 100mm silicon wafer. Five wafers were placed vertically in chamber.
{| class="wikitable"
 
|-
Experiment parameters:
!  !! Single substrate !! Center of 3 substrates
{| {{table}}
|-
| align="center" |  
! scope=row style="text-align: left;" | Test results: ashing rate
{| border="1" cellspacing="1" cellpadding="2"  align="center"
| 5.7 ±2.1 nm/min|| 3.8 ±1.6 nm/min
|- style="background:LightGrey"
|-
| ||O2 flow|| N2 flow || Power
! scope=row style="text-align: left;" | Test results: non-uniformity
|-  
| 0.6 ±0.4% || 0.4 ±0.2%
|'''recipe 1''' || 100 || 100 || 150
|-
! scope=row style="text-align: left;" | Wafers
| 1 || 3
|-
! scope=row style="text-align: left;" | Wafer size
| 100 mm || 100 mm
|-
! scope=row style="text-align: left;" | Boat position
| Center of chamber || Center of chamber
|-
! scope=row style="text-align: left;" | Test wafer position
| Center of boat || Center of boat
|-
! scope=row style="text-align: left;" | Total gas flow rate
| 200 sccm || 200 sccm
|-
! scope=row style="text-align: left;" | Gas mix ratio
| 50% N<sub>2</sub> || 50% N<sub>2</sub>
|-
! scope=row style="text-align: left;" | Chamber pressure
| 1.3 mbar || 1.3 mbar
|-
! scope=row style="text-align: left;" | Power
| 200 W || 200 W
|-
|-
|'''recipe 2''' || 500 || 0 || 200
! scope=row style="text-align: left;" | Test processing time
| Tested parameter || Tested parameter
|-
|-
|}
! scope=row style="text-align: left;" | Test average temperature
| 33°C || 33°C
|}
|}


<br clear="all" />


==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]]


'''recipe 1'''
{| class="wikitable" style="text-align: center;"
{| {{table}}
|+ style="caption-side: top; text-align: left;" | Ashing amount and rate
| align="center" |
{| border="1" cellspacing="1" cellpadding="2"  align="center"
|- style="background:LightGrey"
|'''Ashing time (min)'''|| 1|| 2 || 3 || 4 || 6 || 7 || 8 || 9 || 10 || 12 || 14 || 15 || 20
|-
|'''Etched Thickness (nm)'''|| 8,7 || 5,1 || 12,5 || 6,2 || 31,8 || 86,0 || 25,7 || 46,8 || 38,3 || 49,7 || 59,4 || 140,1 || 360,7
|-
|-
|'''Initial temperature (°C)'''|| 28 || 21 || 31 || 21 || 22 || 28 || 25 || 24 || 21 || 24 || 24 || 22 || 22
! style="text-align: left;" | Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
|-
|-
|}
| style="text-align: left;" | Ashing amount [nm]: || 5.2 || 6.2 || 35.1 || 72.3 || 87.1
|-
| style="text-align: left;" | Ashing rate [nm/min]: || 5.2 || 3.1 || 7.0 || 7.2 || 5.8
|}
|}


 
{| class="wikitable" style="text-align: center;"
 
|+ style="caption-side: top; text-align: left;" | Ashing non-uniformity
[[image:graf_descum-recipe2.png|right|frame|355x355px|Descum results plasma asher 2 - recipe 2]]
|-
 
! style="text-align: left;" | Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
'''recipe 2'''
|-
{| {{table}}
| style="text-align: left;" | Pre-descum film thickness range [nm]: || 11 || 12 || 10 || 11 || 9
| align="center" |
|-
{| border="1" cellspacing="1" cellpadding="2"  align="center"
| style="text-align: left;" | Pre-descum non-uniformity [%]: || 0.37 || 0.40 || 0.33 || 0.37 || 0.30
|-
|- style="background:LightGrey"
| style="text-align: left;" | Post-descum film thickness range [nm]: || 10 || 10 || 12 || 19 || 33
|'''Ashing time (min)'''|| 1 ||2 ||3 ||4 ||5 ||6 ||7 ||8 ||10 ||12 ||15 ||20
|-  
|'''Etched Thickness (nm)'''||8,1 ||9,4 ||16,8 ||55,2 ||44,0 ||47,5 ||42,5 ||55,1 ||85,3 ||122,4 ||184,8 ||305,9
|-  
|'''Initial temperature (°C)'''||22 ||21 ||21 ||22 ||22 ||22 ||21 ||21 ||20 ||21 ||21 ||22
|-
|-
|}
| style="text-align: left;" | Post-descum non-uniformity [%]: || 0.33 || 0.33 || 0.41 || 0.66 || 1.18
|}
|}
We can observe linear dependance of etched material on time after etching 7 minutes and more (recipe 2).
Jitka Urbánková & Jesper Hanberg
December 2019


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


===[http://labadviser.nanolab.dtu.dk/index.php/Specific_Process_Knowledge/Lithography/Strip#Plasma_Asher_3: Plasma asher 3]===
==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]]
Plasma Asher 3 is specially used for control descum process after lithography. Please notice that you only can process one 4 inch wafer or one small sampel ad time.
Machine is equipt with 2 gaslines: oxydgen and nitrogen, but all test run with oxydgen as recommended by Diener.
 
'''Ashing of  AZ MiR701 resist'''
 
You can use different strategy planing your descum: you can change power settings or you can vary chamber pressure during descum.
 
''Testing different power settings''
 
[[image:AZMIR701_power_settings.png|right|frame|400x400px| Descum results for different power settings]]


Recipe settings:
{| class="wikitable" style="text-align: center;"
Kept oxygen and pressure settings constant at Oxydgen: 5 sccm under process; Pressure: 0,2mbar and vary power.
|+ style="caption-side: top; text-align: left;" | Ashing amount and rate
 
Experiment parameters:
{| {{table}}
| align="center" |
{| border="1" cellspacing="1" cellpadding="2"  align="center"
|- 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;" | Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
|-
|-
|'''recipe 3''' || 20/0 || 51/34 || 20%
| style="text-align: left;" | Ashing amount [nm]: || 4.3 || 6.7 || 10.1 || 39.5 || 78.8
|-
|-
| style="text-align: left;" | Ashing rate [nm/min]: || 4.3 || 3.4 || 2.0 || 4.0 || 5.3
|}
|}
|}
<br clear="all" />


''Testing different pressure settings''
{| class="wikitable"  style="text-align: center;"
 
|+ style="caption-side: top; text-align: left;" | Ashing non-uniformity
Recipe settings:
|-
Kept power setting constant at Power: 100% and vary oxydgen flow during process.
! style="text-align: left;" | Ashing time [min]: !! 1 !! 2 !! 5 !! 10 !! 15
 
|-
[[image:AZMIR701_pressure_settings.png|right|frame|400x400px| Descum results for different pressure settings]]
| style="text-align: left;" | Pre-descum film thickness range [nm]: || 11 || 13 || 11 || 12 || 14
 
|-
 
| style="text-align: left;" | Pre-descum non-uniformity [%]: || 0.37 || 0.43 || 0.37 || 0.40 || 0.46
Experiment parameters:
{| {{table}}
| align="center" |  
{| border="1" cellspacing="1" cellpadding="2"  align="center"
|- style="background:LightGrey"
| ||FW/REV|| C2/C1 || Oxydgen || Pressure
|-  
|'''recipe 1'''|| 100/0 || 53/31 || 5 || 0,2
|-
|-
|'''recipe 2''' || 100/0 || 37/38 || 45 || 0,8
| style="text-align: left;" | Post-descum film thickness range [nm]: || 11 || 9 || 10 || 12 || 21
|-
|-
|}
| style="text-align: left;" | Post-descum non-uniformity [%]: || 0.37 || 0.30 || 0.33 || 0.41 || 0.74
|}
|}


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


'''Ashing of AZ5214E resist'''
==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:
<gallery mode="packed-hover" heights="150">
PA_descum_compareAmount_v1.png|Ashing amount
PA_descum_compareRate_v1.png|Ashing rate
PA_descum_compareUniformity_v1.png|Non-uniformity
</gallery>


[[image:AZ5214E_pressure_settings.png|right|frame|400x400px| Descum results for different pressure settings]]
<br clear="all" />


Recipe settings:
==Comparison of ashing rate between substrate sizes==
Kept power setting constant at Power: 100% and vary oxydgen flow during process.
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=
Product name: PVA Tepla Gigabatch 380M<br>
Year of purchase: 2024


Experiment parameters:
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]].
{| {{table}}
| align="center" |
{| border="1" cellspacing="1" cellpadding="2"  align="center"
|- style="background:LightGrey"
| ||FW/REV|| C2/C1 || Oxydgen || Pressure
|-
|'''recipe 1'''|| 100/0 || 53/31 || 17 || 0,4
|-
|'''recipe 2''' || 100/0 || 37/39 || 45 || 0,8
|-
|}
|}
<br clear="all" />

Latest revision as of 16:39, 6 March 2025

The contents 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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