Fully-printed stretchable thin-film transistors and integrated logic circuits
Printable and stretchable thin-film devices and fabrication techniques are provided for forming fully-printed, intrinsically stretchable thin-film transistors and integrated logic circuits using stretchable elastomer substrates such as polydimethylsiloxane (PDMS), semiconducting carbon nanotube network as channel, unsorted carbon nanotube network as source/drain/gate electrodes, and BaTiO 3 /PDMS composite as gate dielectric. Printable stretchable dielectric layer ink may be formed by mixing barium titanate nanoparticle (BaTiO 3 ) with PDMS using 4-methyl-2-pentanone as solvent.
1. A thin-film device comprising:
a stretchable elastomer substrate; and
one or more thin-film transistor elements comprising a source electrode, a drain electrode, and a gate electrode each formed of carbon nanotubes (CNTs) and comprising a stretchable hybrid gate dielectric, the one or more thin-film transistor elements each being printed on the stretchable elastomer substrate and forming one or more stretchable thin-film transistor elements;
wherein the hybrid gate dielectric comprises barium titanate (BaTiO3) nanoparticles dispersed in polydimethylsiloxane (PDMS) as a gate insulator; and
wherein the BaTiO3 nanoparticles are cubic phase BaTiO3 nanoparticles.
2. The thin-film device of claim 1 , wherein the BaTiO3 nanoparticles have a particle size of 50 nm.
3. The thin-film device of claim 1 , wherein at least some of the carbon nanotubes extend between the source electrode and the drain electrode and comprise semiconducting single-walled carbon nanotubes.
4. The thin-film device of claim 1 , wherein the carbon nanotubes of the source electrode, the drain electrode, and the gate electrode are unsorted carbon nanotubes.
5. The thin-film device of claim 1 , further comprising a PDMS encapsulation layer encapsulating the one or more stretchable thin-film transistor elements.
6. The thin-film device of claim 1 , wherein the one or more stretchable thin-film transistor elements are stretchable beyond a 50% strain along a channel length.
7. The thin-film device of claim 6 , wherein the one or more stretchable thin-film transistor elements are stretchable beyond a 60% strain along the channel length.
8. The thin-film device of claim 6 , wherein the one or more stretchable thin-film transistor elements are stretchable beyond a 100% strain along the channel length.
9. The thin-film device of claim 1 , wherein the one or more stretchable thin-film transistor elements are stretchable beyond a 50% strain along a channel width.
10. The thin-film device of claim 9 , wherein the one or more stretchable thin-film transistor elements are stretchable beyond a 60% strain along the channel width.
11. The thin-film device of claim 7 , wherein the one or more stretchable thin-film transistor elements are stretchable beyond a 100% strain along the channel width.
12. The thin-film device of claim 1 , wherein the one or more thin-film transistor elements are connected to form an inverter.
13. The thin-film device of claim 1 , wherein the one or more thin-film transistor elements are connected to form a NOR gate.
14. The thin-film device of claim 1 , wherein the one or more thin-film transistor elements are connected to form a NAND gate.
15. The thin-film device of claim 1 , comprising a plurality of stretchable thin-film transistor elements, wherein the plurality of stretchable thin-film transistor elements comprises an inverter, a NOR gate, and/or a NAND gate.
16. The thin-film device of claim 1 , wherein the stretchable elastomer substrate is a polydimethylsiloxane (PDMS) substrate, a silicone substrate, a polyurethaneacrylate (PUA) substrate, or a thermoplastic elastomer (TPE) substrate.