Wafer assembly comprising MEMS wafer with polymerized siloxane attachment surface
View Patent ↗A wafer assembly comprises a wafer having a MEMS layer formed on a frontside and a polymer coating covering the MEMS layer. A holding means is releasably attached to the polymer coating so that the wafer assembly facilitates performance of backside operations on a backside of the wafer. The polymer coating is comprised of a polymerized siloxane.
1. A wafer assembly comprising:
a wafer having a MEMS layer formed on a frontside thereof and a polymer coating covering said MEMS layer, said polymer coating being comprised of a polymerized siloxane; and
a first holding means releasably attached to said polymer coating, such that said wafer assembly facilitates performance of backside operations on a backside of said wafer.
2. The wafer assembly of claim 1 , wherein said polymer coating is resistant to removal by an oxidative plasma.
3. The wafer assembly of claim 1 , wherein said polymer coating is hydrophobic.
4. The wafer assembly of claim 1 , wherein the polymer coating has a Young's modulus of less than 1000 MPa.
5. The wafer assembly of claim 1 , wherein said polymer coating is photopatternable.
6. The wafer assembly of claim 1 , wherein said polymer coating is comprised of polydimethylsiloxane (PDMS).
7. The wafer assembly of claim 1 , wherein said MEMS layer comprises a plurality of inkjet nozzle assemblies.
8. The wafer assembly of claim 1 , wherein said polymer coating has a plurality of frontside dicing streets defined therethrough.
9. The wafer assembly of claim 1 , wherein said MEMS layer has a plurality of frontside dicing streets defined therethrough.
10. The wafer assembly of claim 1 , wherein the backside operations are selected from the group consisting of:
backside wafer thinning;
backside etching of dicing streets so as to singulate said wafer into individual integrated circuits;
backside etching of ink supply channels so as to provide a fluidic connection between said backside and inkjet nozzle assemblies in said MEMS layer;
subjecting said backside to an oxidative plasma.
11. The wafer assembly of claim 1 , wherein said first holding means is releasably attached to said polymer coating by means of an adhesive tape.
12. The wafer assembly of claim 1 , wherein said first holding means is a handle wafer.
13. The wafer assembly of claim 1 , further comprising:
a second holding means releasably attached to said backside of the wafer.
14. The wafer assembly of claim 7 , wherein said polymer coating has a plurality of nozzle openings defined therethrough, each of said nozzle openings being aligned with a nozzle opening of a respective inkjet nozzle assembly.
15. The wafer assembly of claim 10 , wherein said backside wafer thinning comprises one or more of:
wafer grinding; and
plasma etching.
16. The wafer assembly of claim 11 , wherein said adhesive tape is a UV release tape or a thermal release tape.
17. The wafer assembly of claim 13 , wherein said second holding means is selected from the group consisting of: a handle wafer and a wafer film frame.
18. A wafer for attachment to a holding means, said wafer having a MEMS layer formed on a frontside thereof and a polymer coating covering said MEMS layer, said polymer coating defining a surface for attachment to the holding means, wherein said polymer coating is comprised of a polymerized siloxane.
19. The wafer of claim 18 , wherein said polymer coating is comprised of polydimethylsiloxane (PDMS).
20. The wafer of claim 18 , wherein said MEMS layer comprises a plurality of inkjet nozzle assemblies.