UA Biophysics:Protocols:Microfluidics Valves

Upper Section (Control Layer)

1. Mix PDMS with curing agent 5:1 respectively (30 g PDMS - 6g Curing Agent) inside a plastic glass and use a plastic fork to mix during 5 minutes
2. Place the mixture inside the degasser for 60 min until all bubbles are gone
3. Pour the mixture over the master
4. Place the master at 65°C for 33 min
5.Leave PDMS for two hours at room temperature

Lower Section (Flow Layer)

1. Mix PDMS with curing agent in a 20:1 proportion (20g PDMS: 1g Curing Agent)
2. Pour only a little PDMS on the wafer
3. Use dirty sticky tape to place the master on the spinner
4. Spin for 1 min at 2500 RPM
5. Place the wafer @ 65°C for 33 min
6. Let the wafer cool down at room temperature for two hours

Thermal Bonding

1. Take both stacks out from the oven
2. Punch holes with 3/4 mm puncher in the upper layer
3. Cut the squares for the upper layer with a new razor blade and clean the chip with magic tape
4. Place the upper layer chips on the lower layer so that rectangles match
5. Place bonded surfaces @ 65°C for 4 hours
6. Cut whole chips from wafer with a new razor blade
7. Punch holes for the flow layer

Return to Protocols