Specific Process Knowledge/Lithography/Descum

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Plasma Asher 1

Descum results plasma asher 1. September 2019

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

Descum of AZ5214E resist on 50mm silicon wafer. Wafer was placed horisontally in chamber on a 100 mm carier wafer.

Recipe 1:
Note: Plasma asher was cold before use

• O2 flow: 70 ml/min
• N2 flow: 70 ml/min
• Power: 150 W

Ashing time (min) 1 2 5 7 10 10 Etched Thickness (nm) 14.2 16.3 47.6 123.2 854.3 862.1

Recipe 2:
Note: Plasma asher was cold before use

• O2 flow: 500 ml/min
• N2 flow: 0 ml/min
• Power: 500 W

Ashing time (min) 1 2 5 7 10 10 Etched Thickness (nm) - 8.1 32.9 271.1 495.6 446.2

Descum tests on UV resists

Conny Hjort & Jesper Hanberg, September 2021

Descum results plasma asher 1. August 2021

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.

Recipe settings:
Note: plasma Asher was cold before use.

• O2 flow: 70 ml/min
• N2 flow: 70 ml/min

Power: 150 W

Minor temperature rise during processing was observed, but not more than 5 degrees. Starting chamber pressure was around 0.5 mbar.

1,5 um AZ5214E resist:

Ashing time (min) 1 2 3 5 7 Etched Thickness (nm) 6,28 102,99 76,92 N/A N/A

1,5 um AZ5214E resist placed horizontally in the carrier:

Ashing time (min) 1 2 3 5 7 Etched Thickness (nm) 63,03 143,32 304,29 372,59 N/A

1,5 um AZ701MiR resist:

Ashing time (min) 1 2 3 5 7 Etched Thickness (nm) 268,88 199,54 219,03 200,86 292,15

1,5 um AZ 2020nLOF resist:

Ashing time (min) 1 2 3 5 7 Etched Thickness (nm) 1,68 76,51 169,72 481,96 272,59

Plasma Asher 2

Jitka Urbánková & Jesper Hanberg, December 2019

Descum results plasma asher 2 - recipe 1

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

Descum of AZ Mir 701 resist on 100mm silicon wafer. Five wafers were placed vertically in chamber.

recipe 1:

• O2 flow: 100 ml/min
• N2 flow: 100 ml/min
• Power: 150 W

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

Descum results plasma asher 2 - recipe 2

recipe 2:

• O2 flow: 500 ml/min
• N2 flow: 0 ml/min
• Power: 200 W

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

A linear time dependence was observed after etching 7 minutes or more (recipe 2).

Plasma Asher 3: Descum

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).

Ashing of AZ MiR701 resist:
You can use two different descum process developments: you can either change power settings or processing chamber pressure.

Testing different power settings:

Descum results for different power settings

Recipe settings:

• O2 flow: 5 sccm
• N2 flow: 0
• Pressure: 0.2 mbar
• Power: Varied

Experiment parameters:

FW/REV C2/C1 Power recipe 1 50/0 52/31 50% recipe 2 100/0 53/31 100% recipe 3 20/0 51/34 20%

Testing different pressure settings:

Descum results for different pressure settings

Recipe settings:

• O2 flow: varied
• N2 flow: 0
• Pressure: varied
• Power: V100% (100 W)

Experiment parameters:

FW/REV C2/C1 Oxygen Pressure recipe 1 100/0 53/31 5 0,2 recipe 2 100/0 37/38 45 0,8

Ashing of AZ5214E resist:

Descum results for different pressure settings

Recipe settings:

• O2 flow: varied
• N2 flow: 0
• Pressure: varied
• Power: V100% (100 W)

Experiment parameters:

FW/REV C2/C1 Oxygen Pressure recipe 1 100/0 53/31 17 0,4 recipe 2 100/0 37/39 45 0,8