Configurationally controlled N,N'-Dicycloalkyl-substituted naphthalene-based tetracarboxylic diimide compounds as N-type semiconductor materials for thin film transistors
View Patent ↗A thin film transistor comprises a layer of organic semiconductor material comprising a configurationally controlled N,N′-dicycloalkyl-substituted naphthalene-1,4,5,8-bis-carboximide compound having a substituted or unsubstituted alicyclic ring independently attached to each imide nitrogen atom with the proviso that at least one of the two alicyclic rings is necessarily a 4-substituted cyclohexyl ring in which a substituent at the 4-position is the sole substituent on the 4-substituted cyclohexyl ring other than the imide attachment; with such substituent being stereochemically disposed as only one of either an essentially trans or cis position, respectively, to the imide nitrogen substituent. Such transistors can further comprise spaced apart first and second contact means or electrodes in contact with said material. Further disclosed is a process for fabricating an organic thin-film transistor device, preferably by sublimation deposition onto a substrate, wherein the substrate temperature is no more than 100° C.
1. An article comprising, in a thin film transistor, a thin film of organic semiconductor material that comprises a configurationally controlled N,N′-dicycloalkyl-substituted naphthalene-1,4,5,8-bis-carboximide compound having two independently substituted or unsubstituted alicyclic rings each attached to each imide nitrogen with the proviso that at least one of the two alicyclic rings is necessarily a 4-substituted cyclohexyl ring in which a substituent at the 4-position is the sole substituent on the 4-substituted cyclohexyl ring other than the imide nitrogen attachment, wherein said substituent is stereochemically disposed as either an essentially trans or essentially cis position, respectively, to the imide nitrogen substituent.
2. The article of claim 1 , wherein the N,N′-dicycloalkyl-substituted naphthalene tetracarboxylic diimide compound is represented by the following general Structures I(a) and I(b):
wherein Structure I(b) represents a cis configuration with respect to the R 4 group, and Structure I(a) represents a trans configuration with respect to the R 4 group; R 4 is an inorganic or organic substituent; A 1 is a substituted or unsubstituted alicyclic ring system comprising 4 to 10 carbons in the ring; Y groups are independently selected organic or inorganic groups that do not adversely affect the n-type semiconductor properties of the film made from the diimide compounds, and wherein m is any integer from 0 to 4.
3. The article of claim 2 , wherein A 1 is a substituted or unsubstituted cyclohexyl ring, which if substituted can be cis, trans, or a mixture thereof.
4. The article of claim 2 wherein R 4 is selected from CH 3 , linear or branched C 2 -C 8 alkyl, alkenyl, alkoxy, or other organic group having 1 to 8 carbon atoms.
5. The article of claim 2 wherein A 1 is a monocyclic ring or bicyclic alicyclic hydrocarbon ring.
6. The article of claim 2 wherein the Y groups are selected from the group consisting of alkyl, alkenyl, alkoxy, aryl, arylalkyl, fluorine, chlorine, cyano, fluorine-containing alkyl, carbonyl-containing, and carboxy-containing groups.
7. The article of claim 2 wherein the A 1 ring system is a substituted or unsubstituted cyclohexyl or cyclopentyl ring.
8. The article of claim 2 , wherein the thin film of organic semiconductor material comprises a N,N′-dicylcoalkyl-substituted-1,4,5,8-naphthalene tetracarboxylic acid diimide compound represented by the following Structures II(a) and (b):
wherein R 4 on a primary cyclohexyl ring is an organic or inorganic substituent, and R 8 on a secondary cyclohexyl ring system is independently H or an inorganic or organic substituent, wherein each of R 4 and, if substituted, R 8 are either one, but only one, of an essentially trans or cis configuration with respect to the attachment to the imine nitrogen.
9. The article of claim 8 wherein R 4 and R 8 groups are both organic groups having 1 to 8 carbon atoms.
10. The article of claim 9 wherein both of the primary and secondary cyclohexyl ring systems in the compound comprise a single substituent other than the attachment at the imine nitrogen.
11. The article of claim 8 wherein the secondary alicyclic ring has a single substituent other than the imine attachment.
12. The article of claim 2 wherein the A 1 ring system in the structure is a monocyclic alicyclic ring system having 5 to 6 carbon ring atoms, unsubstituted or substituted.
13. The article of claim 2 , wherein in said structures the R 4 group is selected from C 1 -C 8 organic group.
14. The article of claim 13 , wherein in said structures the organic groups are selected from CH 3 , linear or branched C 2 -C 8 alkyl, C 1 -C 8 alkylene, C 1 -C 8 alkoxy, C 1 -C 8 carbonyl-containing, and carboxy or carbonyl-containing groups.
15. The article of claim 2 , wherein A 1 is substituted with a moiety comprising a N,N′-cycloalkyl-substituted naphthalene-1,4,5,8-bis-carboiximide group, attached directly or indirectly through one of the imide nitrogens.
16. The article of claim 2 , wherein R 4 is an inorganic substituent selected from the group consisting of nitro, fluorine, cyano, amino, and sulfo.
17. The article of claim 1 wherein the thin film transistor is a field effect transistor comprising a dielectric layer, a gate electrode, a source electrode and a drain electrode, and wherein the dielectric layer, the gate electrode, the thin film of organic semiconductor material, the source electrode, and the drain electrode are in any sequence as long as the gate electrode and the thin film of organic semiconductor material both contact the dielectric layer, and the source electrode and the drain electrode both contact the thin film of organic semiconductor material.
18. The article of claim 17 , wherein the gate electrode is adapted for controlling, by means of a voltage applied to the gate electrode, a current between the source and drain electrodes through the thin film of organic semiconductor material.
19. The article of claim 17 wherein the dielectric layer comprises an inorganic or organic electrically insulating material.
20. The article of claim 17 wherein the source, drain, and gate electrodes each independently comprise a material selected from doped silicon, metal, and a conducting polymer.
21. The article of claim 1 wherein the thin film of organic semiconductor material is capable of exhibiting electron mobility greater than 0.01 cm 2 /Vs.
22. The article of claim 1 wherein both of said alicyclic rings in the compound are cyclohexyl rings and wherein the alicyclic ring other than the 4-substituted cyclohexyl ring is either not substituted or, like the 4-subsituted cyclohexyl ring, has a sole substituent other than the attachment at the imine nitrogen.
23. The article of claim 1 , wherein in said structure the substituents, if any, on the alicyclic ring other than the 4-substituted cyclohexyl ring are selected from CH 3 , linear or branched C 2 -C 8 alkyl, alkenyl, alkoxy, or other organic group having 1 to 8 carbon atoms.
24. The article of claim 1 , wherein the thin film transistor has an on/off ratio of a source/drain current of at least 10 4 .
25. The article of claim 1 wherein the thin film transistor further comprises a non-participating support that is optionally flexible.
26. An electronic device selected from the group consisting of integrated circuits, active-matrix display, and solar cells comprising a multiplicity of thin film transistors according to claim 1 .
27. The electronic device of claim 26 wherein the multiplicity of the thin film transistors is on a non-participating support that is optionally flexible.
28. A process for fabricating a thin film semiconductor device, comprising, not necessarily in the following order, the steps of:
(a) depositing, onto a substrate, a thin film of n-channel organic semiconductor material that comprises a configurationally controlled N,N′-dicycloalkyl-substituted naphthalene-1,4,5,8-bis-carboximide compound having a substituted or unsubstituted alicyclic ring independently attached to each imide nitrogen atom with the proviso that at least one of the two alicyclic rings is necessarily a 4-substituted cyclohexyl ring in which a substituent at the 4-position is the sole substituent on the 4-substituted cyclohexyl ring other than the imide attachment; with such substituent being stereochemically disposed as only one of either an essentially trans or cis position, respectively, to the imide nitrogen substituent, such that the organic semiconductor material exhibits a field effect electron mobility that is greater than 0.01 cm 2 /Vs;
(b) forming a spaced apart source electrode and drain electrode,
wherein the source electrode and the drain electrode are separated by, and electrically connected with, the n-channel semiconductor film; and,
(c) forming a gate electrode spaced apart from the organic semiconductor material.
29. The process of claim 28 , wherein said compound is deposited on the substrate by sublimation and wherein the substrate has a temperature of no more than 100° C. during deposition.
30. The process of claim 28 , wherein the compound is N,N′-(trans-4-methyl-cyclohexyl, cyclohexyl)-naphthalene-1,4,5,8 tetracarboxylic acid diimide, N,N′-(trans-4-methyl-cyclohexyl, cyclohexyl)-naphthalene-1,4,5,8 tetracarboxylic acid diimide, or N,N′-(cis-4-methyl-cyclohexyl, cyclohexyl)-naphthalene-1,4,5,8 tetracarboxylic acid diimide.