Method for fabricating thermoplastic fluidic devices by orogenic growth and fluidic devices manufactured thereby
A new process enabling rapid and efficient desktop manufacturing of microfluidic devices fabricated from thermoplastic substrates utilizing the selective irreversible swelling of thermoplastic polymer when exposed to suitable solvent makes it possible to produce micro- or nano-fluidic devices with outstanding bonding and collapse free micro- or nano-structures.
1. A method for manufacturing devices, comprising:
masking a first substrate comprising a thermoplastic polymer;
forming a channel by exposing the masked first substrate to a solvent so that the thermoplastic polymer exposed to the solvent swells and grows in height forming walls of the channel around the masked area; and
bonding the first substrate with a second substrate such that the channel is formed between the first and second substrate.
2. The method for manufacturing devices according to claim 1 , wherein the thermoplastic polymer comprises a cyclic olefin polymer and/or a cyclic olefin copolymer.
3. The method for manufacturing devices according to claim 2 , wherein
the cyclic olefin copolymer comprises a product of chain copolymerization of one or more cyclic hydrocarbon monomers with an alkene.
4. The method for manufacturing devices according to claim 3 , wherein
at least one cyclic hydrocarbon monomer contains at least one ring, has 3-25 carbon atoms, and optionally has one or more side chains.
5. The method for manufacturing devices according to claim 4 , wherein
the cyclic hydrocarbon monomer is at least one of norbornene or tetracyclododecane.
6. The method for manufacturing devices according to claim 3 , wherein
the alkene has a branched or straight chain and contains 2-12 carbon atoms.
7. The method for manufacturing devices according to claim 6 , wherein
the alkene comprises ethene.
8. The method for manufacturing devices according to claim 1 , wherein
the solvent has a solubility parameter that differs from a solubility parameter of the thermoplastic polymer by more than 1% and no more than 8%.
9. The method for manufacturing devices according to claim 8 , wherein
the solvent has a solubility parameter that differs from a solubility parameter of the thermoplastic polymer by more than 4% and no more than 6%.
10. The method for manufacturing devices according to claim 2 , wherein
the solvent comprises cyclohexane.
11. The method for manufacturing devices according to claim 1 , wherein
the masking step comprises at least one method selected from the group consisting of photolithography, UV/O 3 masking, contact printing, inkjet printing and probe deposition of a protective composition.
12. The method for manufacturing devices according to claim 1 , wherein
the second substrate comprises a thermoplastic polymer with a solubility parameter that differs from the solubility parameter of the solvent by more than 4% and no more than 6%.
13. The method for manufacturing devices according to claim 1 , wherein
the second substrate comprises the same thermoplastic polymer as the thermoplastic polymer of the first substrate.
14. The method for manufacturing devices according to claim 2 , wherein
the second substrate comprises cyclic olefin copolymer.
15. The method for manufacturing devices according to claim 12 , wherein
the bonding step comprises solvent bonding.
16. The method for manufacturing devices according to claim 15 , wherein
the bonding step is carried out at room temperature.
17. The method for manufacturing devices according to claim 15 , wherein
the bonding step is carried out under a pressure of no more than 500 psi.
18. The method for manufacturing devices according to claim 15 , wherein a burst pressure for the channel formed by the bonding between the first and second substrates is more than 10 MPa.
19. The method for manufacturing devices according to claim 15 , wherein a burst pressure for the channel formed by the bonded first and second substrates is more than 15 MPa.
20. The method for manufacturing devices according to claim 15 , further comprising:
forming a seal at an isolation member region within the device, wherein a burst pressure of the channel formed by the bonded first and second substrates is lower at a point at the seal than the burst pressure of the bonded first and second substrates at a point not at the seal.
21. The method for manufacturing devices according to claim 20 , wherein bonding between the first and second substrates at the isolation member region is performed by thermal bonding.