Specific Process Knowledge/Lithography/Descum
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.
Plasma Asher 2
Plasma asher 2 was decommissioned 2024-12-02.
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:
Recipe settings:
- O2 flow: 5 sccm
- N2 flow: 0
- Pressure: 0.2 mbar
- Power: Varied
Experiment parameters:
|
Testing different pressure settings:
Recipe settings:
- O2 flow: varied
- N2 flow: 0
- Pressure: varied
- Power: V100% (100 W)
Experiment parameters:
|
Ashing of AZ5214E resist:
Recipe settings:
- O2 flow: varied
- N2 flow: 0
- Pressure: varied
- Power: V100% (100 W)
Experiment parameters:
|
Plasma Asher 4
Descum processing in plasma asher 4 & 5
The user manual, risk assessment, and contact information can be found in LabManager - requires login
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.
| Test setup | Single substrate | Center of 3 substrates |
|---|---|---|
| Test results | Ashing rate: 5.7 ±2.1 µm/min Non-uniformity: 0.6 ±0.4% |
Ashing rate: 3.8 ±1.6 µm/min Non-uniformity: 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 |
Plasma Asher 5
Coming soon