Specific Process Knowledge/Lithography/Development/Developer TMAH UV-lithography processing
This page is under construction
General Process Information
Processing using Spin Track 1 + 2 is divided into three parts:
- HMDS priming
- Spin coating
- Soft baking
As part of the processing of negative tone resists and chemically amplified positive tone resists, Spin Track 2 may also be used for:
- Post-exposure baking (at 110°C)
Features of Spin Track 1 + 2:
- Cassette-to-cassette wafer handling
- In-line HMDS priming
- Temperature controlled resist lines
The resist lines are temperature controlled using 25°C water from a chiller. The priming module coolplate is cooled by the same chiller. If the process flow has been properly designed, the wafer and resist should have the same temperature during spin coating, ensuring good coating reproducibility.
Puddle Development
The process of development
Rinse
After development, the substrate is rinsed using DI water, and dried using nitrogen.
The standard rinse and dry procedure is 30s at 4000rpm with DIW being administered from the top at the center of the substrate, followed by a 10-15s dry using nitrogen from the top at the center of the substrate. The top side rinse is at a rate of approximately 500 ml/min, corresponding to 250 ml DIW during the rinse. The flow rate of the nitrogen is 50 l/min, and the drying time is set according to the size of the substrate.
Post-exposure baking
Chemically amplified resists and cross-linking negative resists must be baked after exposure in order to finish the process initiated by the exposure light. Post-exposure bake, or PEB, is carried out on one of the two hotplates. After baking, the wafer is cooled for 20 seconds on the 20°C coolplate.
Standard Processes
Puddle development
Development on Developer TMAH UV-lithography is divided into the following steps: Pre-wet, puddle dispense, development, spin-off, and finally rinse and dry.
Sequence names and process parameters:
- DCH 100mm SP 30s
- DCH 100mm SP 60s
- DCH 100mm SP 120s
- DCH 150mm SP 60s
Each of these sequences start with a 2s pre-wet at 1200 rpm using developer. The puddle dispense is done at a rotation of 30rpm. The dispense time is 3s, and 7s for 100mm, and 150mm, respectively. The development (puddle time) is split in two by an agitation step of 2s at 30rpm (one rotation). Spin-off is 3s at 4000rpm. Finally, the wafer is rinsed as described above.
Post-exposure baking (PEB)
Chemically amplified resists and cross-linking negative resists must be baked after exposure in order to finish the process initiated by the exposure light.
Flow names and process parameters:
- DCH PEB 110C 60s
Process parameters: 60s bake at 110°C. 20s cool at 20°C.
Combined PEB and development
For convenience, the PEB and development function of the machine may be combined in one sequence.
Flow names and process parameters:
- DCH 100mm PEB60s@110C+SP60s
A combination of the 'DCH PEB 110C 60s' post-exposure bake and the 'DCH 100mm SP 60s' development.