Printed material constrained by well structures and devices including same
View Patent ↗A first patterned contact layer, for example a gate electrode, is formed over an insulative substrate. Insulating and functional layers are formed at least over the first patterned contact layer. A second patterned contact layer, for example source/drain electrodes, is formed over the functional layer. Insulative material is then selectively deposited over at least a portion of the second patterned contact layer to form first and second wall structures such that at least a portion of the second patterned contact layer is exposed, the first and second wall structures defining a well therebetween. Electrically conductive or semiconductive material is deposited within the well, for example by jet-printing, such that the first and second wall structures confine the conductive or semiconductive material and prevent spreading and electrical shorting to adjacent devices. The conductive or semiconductive material is in electrical contact with the exposed portion of the second patterned contact layer to form, e.g., an operative transistor.
1. A transistor device, comprising:
a substrate;
a gate electrode formed over said substrate;
a gate dielectric layer formed over said gate electrode and at least a portion of said substrate;
source and drain electrodes formed over said gate electrode such that said source and drain electrodes are spaced apart from said gate electrode in a plane of said gate dielectric layer and further such that a portion of each of said source and drain electrodes overlap a portion of said gate electrode;
a functional layer formed over and in physical contact with said source and drain electrodes and further over and in physical contact with at least a portion of said gate dielectric;
a first insulative wall structure formed over at least a portion of said source electrode such that a region of said source electrode is not covered by said first insulative wall structure and a second insulative wall structure formed over at least a region of said drain electrode such that a portion of said drain electrode is not covered by said second insulative wall structure; and
a semiconductor layer formed over said functional layer and in physical and electrical contact with said exposed regions of said source and drain electrodes, said semiconductor layer laterally confined by the first and second insulative wall structures.
2. The transistor device of claim 1 , wherein said functional layer is a hydrophobic layer, and is selected from the group consisting of: hydrophobic silane, nonpolar polymer, silazane, polysilsesquioxane, and fluorocarbon.
3. The transistor device of claim 1 , wherein said functional layer is a hydrophilic layer, and is selected from the group consisting of: hydrophilic silane, polar polymer, polyethylene glycol, polyethylene oxide, and proteins.
4. The transistor device of claim 1 , wherein functional layer comprises a material that may be deposited in a liquid phase and transition to a solid phase following deposition.
5. The transistor device of claim 1 , wherein said first and second insulative wall structures each comprise a material that may be deposited in a liquid phase and transition to a solid phase following deposition.
6. The transistor device of claim 5 , wherein said first and second insulative wall structures each comprise a wax material.
7. The transistor device of claim 1 , wherein said first and second insulative wall structures are substantially taller than said source and drain electrodes.
8. The transistor device of claim 7 , wherein said first and second insulative wall structures are of a height in the range between 0.5 microns and 5.0 microns above the surface of said functional layer.
9. The transistor device of claim 1 , wherein said first and second insulative wall structures define a well substantially over said gate electrode, said well of a width in the range between 10 microns and 500 microns.
10. The transistor device of claim 1 , wherein said semiconductor layer comprises a material that may be deposited in a liquid phase and transition to a solid phase following deposition.
11. The transistor device of claim 10 , wherein said semiconductor layer includes precursors selected from the group consisting of: pentacene; zinc oxide; silicon; carbon nanotubes; silicon nanowires; silicon nano-belts; grapheme; silicon nano particles; silicon nano-rods; and silicon nano-ribbons.