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.

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.

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

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

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