WO2013089443A1

WO2013089443A1 - Novel diketopyrrolopyrrole polymer and organic electronic element using same

Info

Publication number: WO2013089443A1
Application number: PCT/KR2012/010815
Authority: WO
Inventors: 권순기; 김윤희; 강일
Original assignee: 경상대학교산학협력단
Priority date: 2011-12-15
Filing date: 2012-12-13
Publication date: 2013-06-20
Also published as: WO2013089444A2; WO2013089444A3; KR101443189B1; KR101463397B1; KR20130069446A; KR20130069445A; WO2013089323A1

Abstract

The present invention relates to an organic semiconductor compound for an organic electronic element such as an organic thin film transistor (OTFT) and to the use thereof. More particularly, the present invention relates to a diketopyrrolopyrrole polymer as a novel organic semiconductor compound having high pi-electron overlap by introducing an electron donor compound into a diketopyrrolopyrrole derivative, and also relates to an organic electronic element of which the charge mobility and the on/off ratio are improved by using the diketopyrrolopyrrole polymer as an organic semiconductor layer.

Description

Novel Diketopyrrolopyrrole Polymers and Organic Electronic Devices Using the Same

The present invention relates to an organic semiconductor compound for organic electronic device such as an organic thin film transistor (OTFT) and its use. More specifically, the present invention relates to a diketopyrrolopyrrole polymer and an organic electronic device using the same as an organic semiconductor layer as a novel organic semiconductor compound having a high pi electron stack by introducing an electron donor compound into a diketopyrrolopyrrole derivative. will be.

The development of telecommunications in the 21st century and the desire for personal handheld communication devices are high performance electricity that can produce ultra-fine processing and ultra-high integrated circuits that enable information communication devices that are small in size, light in weight, thin and easy to use. There is a need for new information and communication materials that enable the display of electronic materials and new concepts. Among them, organic thin film transistors (OTFTs) are used for display drivers such as portable computers, organic EL devices, smart cards, electric tags, pagers, mobile phones, and memory devices such as cash machines and identification tags. The possibility of being used as an important component of plastic circuitry has been the subject of much research.

The organic thin film transistor using the organic semiconductor has the advantages of simpler manufacturing process and lower cost production compared to the organic thin film transistor using amorphous silicon and polysilicon, and is compatible with the plastic substrates for implementing the flexible display. Due to this superior advantage, many researches are being made recently. In particular, the use of a polymer organic semiconductor has the advantage that the manufacturing cost can be reduced compared to the low molecular organic semiconductor compound because of the advantage that the thin film can be easily formed by the solution process.

Representative semiconductor compounds for polymer-based organic thin film transistors developed to date include P3HT [poly (3-hexylthiophene)] and F8T2 [poly (9,9-dioctylfluorene-co-bithiophene)]. There are many performances of OTFT, but the most important evaluation scale is charge mobility and on / off ratio, and the most important evaluation scale is charge mobility. The charge mobility varies depending on the type of semiconductor material, thin film formation method (structure and morphology), driving voltage, and the like.

FIG. 1 is a cross-sectional view illustrating a structure of a general organic thin film transistor including a substrate, a gate, an insulating layer, an electrode layer (source, drain), and an organic conductive layer, and a gate electrode is formed on the substrate. An insulating layer is formed on the gate electrode, and an organic semiconductor layer, and a source and a drain electrode are formed in this order. The driving principle of the organic thin film transistor having the above structure will be described with reference to an example of a p-type semiconductor. First, when a current is applied by applying a voltage between the source and the drain, a current proportional to the voltage flows under a low voltage. When a positive voltage is applied to the gate, holes that are positive charges are all pushed up to the top of the semiconductor layer by the electric field by the applied voltage. Thus, the portion close to the insulating layer will have a depletion layer without conduction charge, and in such a situation, a low amount of current will flow due to the reduced number of conducting charge carriers even when a voltage is applied between the source and the drain. . On the contrary, when a negative voltage is applied to the gate, an accumulation layer in which positive charges are induced near the insulating layer is formed by the effect of the electric field caused by the applied voltage. At this time, since there are many conducting charge carriers between the source and the drain, more current can flow. Therefore, the current flowing between the source and the drain can be controlled by alternately applying a positive voltage and a negative voltage to the gate while a voltage is applied between the source and the drain.

The organic thin film transistors, which are constructed on the principle described above, include electrodes (source and drain), substrates and gate electrodes requiring high thermal stability, insulators having high dielectric properties and dielectric constants, and semiconductors that transfer charges well. There are many problems to overcome, and the core material is organic semiconductor. Organic semiconductors can be classified into low molecular organic semiconductors and high molecular organic semiconductors according to molecular weight, and are classified into n-type organic semiconductors or p-type organic semiconductors according to whether electrons or holes are transferred. In general, when a low molecular weight organic semiconductor is used in forming an organic semiconductor layer, the low molecular weight organic semiconductor is easy to purify and almost removes impurities, so the charge transfer characteristics are excellent. However, such organic semiconductors are not spin coated and printed. Therefore, since the thin film must be manufactured by vacuum deposition, the manufacturing process is complicated and expensive compared with the polymer organic semiconductor. In the case of the polymer organic semiconductor, it is difficult to purify the high purity, but excellent heat resistance, spin coating and printing is possible, there is an advantage in the manufacturing process, cost, mass production.

Although many studies have been made to date for the development of organic semiconductor materials, the development of polymer semiconductor materials is still far from the development of low molecular weight semiconductor materials. Therefore, in order to develop an electronic device using a flexible, low-cost organic thin film transistor, it is urgent to develop a polymer semiconductor material. Generally, the charge mobility of a polymer is known to be inferior to that of a low molecule, but it can be said to be a material that can sufficiently overcome this in terms of manufacturing process and cost.

Korean Patent Publication No. 2011-0091711 discloses a polymer in which an S-containing heteroaromatic ring is directly bonded to a diketopyrrolopyrrole group. However, the materials that have emerged so far do not exhibit sufficient expansion of pi electrons, so it is necessary to develop a polymer semiconductor material exhibiting sufficient pi electron overlap.

In addition, Korean Patent Publication No. 2009-0024832 discloses a polymer in which an S-containing heteroaromatic ring is directly bonded, and at the same time, alkyl having 1 to 25 carbon atoms can be substituted for a nitrogen atom of a diketopyrrolopyrrole group. In the examples of the above-mentioned patent, only compounds in which only alkyl having 8, 10 and 16 carbon atoms are substituted are described. However, in the case of the diketopyrrolopyrrole polymer substituted with only 8, 10, and 16 alkyl carbon atoms, which are disclosed in the above-mentioned patents, the solubility is poor and the charge mobility is not sufficient, making it difficult to apply to the actual organic thin film transistor. there was.

The present invention has been completed for the first time to realize that a new diketopyrrolopyrrole polymer having a very good charge mobility as a polymer having an S-containing heteroaromatic ring of the present invention is directly bonded.

It is also an object of the present invention to alternately polymerize a diketopyrrolopyrrole derivative, one of the electron acceptor materials, and an electron donor material, an aromatic material in which a vinylene bond is introduced, to have high air stability and to increase coplanarity of the main chain. And diketopyrrolopyrrole polymers containing a double bond that can exhibit sufficient pi electron expansion by having an expanded conjugated structure, thereby increasing solubility and having significant charge mobility properties. To provide.

In addition, another object of the present invention is to provide a diketopyrrolopyrrole polymer which is a novel organic semiconductor compound that is easy to spin coating at room temperature to enable a solution process.

In addition, another object of the present invention is to provide an organic thin film transistor including a novel diketopyrrolopyrrole polymer in the organic semiconductor layer capable of a high temperature solution process such as high charge mobility and spin coating according to the present invention.

The present invention relates to an organic semiconductor compound for organic electronic device such as an organic thin film transistor (OTFT) and its use. More specifically, the present invention relates to a p-type polymer organic semiconductor compound used as an active layer material of an organic thin film transistor configured to alternately polymerize a diketopyrrolopyrrole derivative as an electron acceptor compound and a compound containing a vinylene group as an electron donor compound. Dyketopyrrolopyrrole polymer and an organic electronic device using the same.

In particular, the inventors of the present invention have unexpected charge mobility, thermal stability, solubility characteristics, oxidation stability, threshold voltage and flashing ratio when the carbon number of the alkyl group substituted at the nitrogen atom of the diketopyrrolopyrrole group is adjusted to 24 or more. The surprising improvement effect was first confirmed to complete the present invention.

Furthermore, the cause is unknown, but when the carbon number of the alkyl group is adjusted to 28 or more, the charge mobility and solubility characteristics are improved as compared to the alkyl group having less than 24 carbon atoms. The present invention has been completed for the first time to recognize that an amazing effect of improved mobility is 1.5 times or more or 2 times or more.

Hereinafter, the present invention will be described in detail.

The organic semiconductor compound of the present invention is a diketopyrrolopyrrole polymer represented by the following formula (1), by introducing a vinylene group (V) increases the coplanarity of the main chain (electron density) by having an expanded conjugated structure Improves intermolecular interactions and high mobility.

[Formula 1]

[In Formula 1,

R ₁ and R ₂ are each independently (C ₂₄ -C 50) alkyl;

L ₁ and L ₂ are each independently selected from the following structures;

V is

ego;

A ₁ and A ₂ are each independently hydrogen, cyano or -COOR ';

R 'is (C1-C50) alkyl or (C6-C50) aryl;

R ₃ to R ₈ are each independently hydrogen, hydroxy group, amino, (C1-C50) alkyl, (C6-C50) aryl, (C1-C50) alkoxy, mono or di (C1-C50) alkylamino, (C1- C50) alkoxycarbonyl or (C1-C50) alkylcarbonyloxy;

m is an integer of 1 or 2, and when m is 2, each of V and L ₂ may be the same or different from each other; And

n is an integer from 1 to 1,000.]

In Chemical Formula 1

Is selected from the following structures.

[A ₁ , A ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ are the same as defined in Formula 1 above.]

More preferably,

Is selected from the following structures.

In addition, in Formula 1, R ₁ and R ₂ are each independently (C28-C50) alkyl, it is preferable that the alkyl includes a linear or branched alkyl.

The diketopyrrolopyrrole polymer of the present invention is specifically selected from the following compounds.

[Where n is an integer of 1 to 1,000.]

Preferably, the diketopyrrolopyrrole polymer of the present invention is selected from the following compounds.

[Wherein n is an integer of 1 to 1,000.]

More preferably, the diketopyrrolopyrrole polymer of the present invention is selected from the following compounds.

[Where n is an integer of 1 to 1,000.]

As a method for preparing the diketopyrrolopyrrole polymer according to the present invention, the final compound may be prepared through an alkylation reaction, a Grignard coupling reaction, a Suzuki coupling reaction, a Stiletto coupling reaction, and the like. The organic semiconductor compound according to the present invention is not limited to the above production method, and may be prepared by a conventional organic chemical reaction in addition to the above production method.

The diketopyrrolopyrrole polymer according to the present invention can be used as a material for forming an organic semiconductor layer of an organic electronic device, specific examples of the manufacturing method of the organic thin film transistor to which it is applied are as follows.

As the substrate 11, it is preferable to use n-type silicon used in a conventional organic thin film transistor. This substrate contains the function of the gate electrode. In addition to n-type silicon, a glass substrate or a transparent plastic substrate having excellent surface smoothness, ease of handling, and waterproofness may be used as the substrate. In this case, a gate electrode must be added on the substrate. Substances which can be employed as the substrate include glass, polyethylenenaphthalate (PEN), polyethylene terephthalate (PET), polycarbonate (PC), polyvinyl alcohol (PVP), polyacrylate (Polyacrylate). , Polyimide, polynorbornene and polyethersulfone (PES).

As the gate insulating layer 12 constituting the OTFT device, an insulator having a high dielectric constant, which is commonly used, may be used. Specifically, Ba _0.33 Sr _0.66 TiO ₃ (BST), Al ₂ O ₃ , Ta ₂ O ₅ , and La ₂ Ferroelectric insulators selected from the group consisting of O ₅ , Y ₂ O ₃ and TiO ₂ , PdZr _0.33 Ti _0.66 O ₃ (PZT), Bi ₄ Ti ₃ O ₁₂ , BaMgF ₄ , SrBi ₂ (TaNb) ₂ O ₉ , Ba (ZrTi ) O ₃ (BZT), BaTiO ₃ , SrTiO ₃ , Bi ₄ Ti ₃ O ₁₂ , SiO ₂ , SiN _x and AlON, an inorganic insulator selected from the group consisting of polyimide, benzocyclobutene (BCB), parylene ( Organic leading bodies such as parylene, polyacrylate, polyvinylalcohol, and polyvinylphenol may be used.

As shown in FIG. 1, the organic thin film transistor of the present invention is composed of the substrate 11, the gate electrode 16, the insulating layer 12, the organic base layer 13, the source 14, and the drain electrode 15. As shown in FIG. It includes both top-contact as well as bottom-contact types of substrate / gate electrode / insulation layer / source and drain electrode / derivative layer. In addition, HMDS (1,1,1,3,3,3-hexamethyldisilazane), OTS (octadecyltrichlorosilane) or OTDS (octadecyltrichlorosilane) may be used as a surface treatment between the source 14 and the drain electrode 15 and the organic semiconductor layer 13. It may or may not be coated.

The organic semiconductor layer employing the diketopyrrolopyrrole polymer according to the present invention may be formed into a thin film through vacuum deposition, screen printing, printing, spin casting, spin coating, dipping or ink spraying, At this time, the deposition of the organic semiconductor layer may be formed using a high temperature solution at 40 ℃ or more, the thickness is preferably about 500 kPa.

The gate electrode 16 and the source and drain

electrodes

14 and 15 may be conductive materials, but gold (Au), silver (Ag), aluminum (Al), nickel (Ni), chromium (Cr), and indium tin may be used. It is preferably formed of a material selected from the group consisting of oxides (ITOs).

Fig. 1-A cross-sectional view showing the structure of a general organic thin film transistor made of a substrate / gate / insulating layer (source, drain) / semiconductor layer.

FIG. 2-UV-vis absorption spectra of solution phase and film phase of organic semiconductor compound (PDPPDBTE) according to Example 1

3-UV-vis absorption spectra of the solution phase and the film phase of the organic semiconductor compound (P28DPP-TVT) according to Example 8

4-UV-vis absorption spectra of the solution phase and the film phase of the organic semiconductor compound (P32DPP-TVT) according to Example 9

5-Cyclic voltammetry diagram of the organic semiconductor compound (PDPPDBTE) according to Example 1

6-Electrical property (cyclic voltammetry) diagram of organic semiconductor compound (P28DPP-TVT) according to Example 8

7-Electrical properties (cyclic voltammetry) of the organic semiconductor compound (P32DPP-TVT) according to Example 9

8-Differential calorimetry (DSC) curve of organic semiconductor compound (PDPPDBTE) according to Example 1

9-Differential calorimetry (DSC) curve of organic semiconductor compound (P28DPP-TVT) according to Example 8

Figure 10-Differential calorimetry (DSC) curve of the organic semiconductor compound (P32DPP-TVT) according to Example 9

11-Thermogravimetric Analysis (TGA) curve of organic semiconductor compound (PDPPDBTE) according to Example 1

12-Thermogravimetric analysis (TGA) of organic semiconductor compound (P28DPP-TVT) according to Example 8

13-Thermogravimetric Analysis (TGA) curve of organic semiconductor compound (P32DPP-TVT) according to Example 9

14-Predicted HOMO and LUMO structure of Example 1 by computer simulation (DFT)

15-AFM images of the device fabricated by the method of Example 10 using the organic semiconductor compound (PDPPDBTE) according to Example 1 (a: film at room temperature, a: film state annealed at 200 ° C., c ) Drawing showing the state of the film annealed at 250 ° C)

16 and 17-a diagram showing the characteristics (transfer curve, output curve) of the device manufactured by the method of Example 10 using the organic semiconductor compound (PDPPDBTE) according to Example 1

18 and 19-a diagram showing the characteristics (transfer curve, output curve) of the device manufactured by the method of Example 10 using the organic semiconductor compound (P28DPP-TVT) according to Example 8

20 and 21-a diagram showing the characteristics (Transfer curve, Output curve) of the device manufactured by the method of Example 10 using the organic semiconductor compound (P32DPP-TVT) according to Example 9

11 substrate 12 insulator

13: organic electronic device layer (channel material) 14: source

15: drain 16: gate

The present invention can be more clearly understood by the following examples, which are only intended to illustrate the present invention and are not intended to limit the scope of the invention.

Preparation Example 1 (E) -1,2-bis (5- (trimethylstannyl) thiophen-2-yl) ethene ((E) -1,2-bis (5- (trimethylstannyl) thiophen-2- synthesis of yl) ethene)

Synthesis of (E) -1,2-bis (thiophen-2-yl) ethene ((E) -1,2-bis (thiophen-2-yl) ethene)

Add thiophene-2-carbaldehyde (5.6 g, 50 mmol) to the flask, dissolve in tetrahydrolyuran (THF) (100 mL), lower the temperature to -18 ° C and add titanium (IV) chloride (6.5 mL) 30 Drop off slowly for minutes. After stirring for 30 minutes, zinc powder (7.8 g) is added over 30 minutes. After stirring at −18 ° C. for 30 minutes, the temperature was raised to room temperature and refluxed for 3 hours 30 minutes. Then pour iced water to terminate the reaction, filter the inorganics with water, wash with methylene chloride, extract, remove the water and recrystallize with hexane to obtain the target compound (E) -1,2-bis (thiophen-2- Il) ethene was obtained (4.7 g, yield: 98%). ¹ H NMR (300 MHz, CDCl ₃ ) [ppm] δ 7.18 (d, 2H), 7.05 (s, 2H), 7.04 (d, 2H), 6.99 (m, 2H).

(E) -1,2-bis (5- (trimethylstannyl) thiophen-2-yl) ethene ((E) -1,2-bis (5- (trimethylstannyl) thiophen-2-yl) ethene) synthesis

Dissolve (E) -1,2-bis (thiophen-2-yl) ethene (1.78 g, 9.6 mmol) in a mixed solvent of tetrahydrofuran / hexane (volume ratio 2/1, 50 mL) in a flask and 2 moles. Of cyclohexane with n-butyllithium (11 ml, 22 mmol) was slowly added at -78 ° C and stirred for 30 minutes. After raising to room temperature to reflux for 1 hour, the reaction was again cooled to -78 ℃. Tetrahydrofuran (22 mL, 22 mmol) in which 1 mol of trimethyltin chloride is dissolved is slowly added dropwise to the reaction at the same temperature, and the mixture is stirred at room temperature for 2 hours. Extract with ether, remove water with anhydrous magnesium sulfate, concentrate the solvent and recrystallize with ethanol to give (E) -1,2-bis (5- (trimethylstannyl) thiophene, the target compound of white needle shape. 2-yl) ethene was obtained (3.88 g, yield: 80%). ¹ H NMR (300 MHz, CDCl ₃ ) [ppm] δ 7.11 (d, 2H), 7.08 (s, 2H), 7.07 (d, 2H), 0.36 (s, 18H).

Preparation Example 2 Synthesis of (E) -1,2-bis (4- (trimethylstannyl) phenyl) ethene ((E) -1,2-bis (4- (trimethylstannyl) phenyl) ethene)

In a flask, (E) -1,2-bis (4-bromophenyl) ethene (3 g, 8.7 mmol) was dissolved in tetrahydrofuran (90 mL), followed by 2 moles of n-butyllithium cyclohexane (7.1 mL, 17.75 mmol) was added slowly at −78 ° C. and stirred for 30 minutes. Trimethyltin chloride (3.53 g, 17.75 mmol) was slowly added dropwise to the reaction at the same temperature and stirred at room temperature for 2 hours. Extract with ether, remove water with anhydrous magnesium sulfate, concentrate the solvent and recrystallize with ethyl alcohol to give (E) -1,2-bis (4- (trimethylstannyl) phenyl) ethene, the target compound as a white powder. Was obtained (3.2 g, yield: 80%). ¹ H NMR (300 MHz, CDCl ₃ ) [ppm] δ 7.50-7.48 (m, 4H), 6.968 (s, 2H), 0.36 (s, 18H).

Preparation Example 3 (E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) thiophen-2-yl) ethene ((E) -1,2-bis (3-dodecyl- Synthesis of 5- (trimethylstannyl) thiophen-2-yl) ethene)

Synthesis of (E) -1,2-bis (3-dodecylthiophen-2-yl) ethene ((E) -1,2-bis (3-dodecylthiophen-2-yl) ethene)

3-dodecylthiophen-2-carbaldehyde (14 g, 50 mmol), tetrahydrofuran (THF) (250 mL), titanium (IV) chloride (6.5 mL), zinc powder (7.8 g) In the same manner as in Preparation Example 1, the target compound (E) -1,2-bis (3-dodecylthiophen-2-yl) ethene was obtained (10 g, yield: 75%). ¹ H NMR (300 MHz, CDCl ₃ ) [ppm] δ 7.18 (d, 2H), 7.05 (d, 2H), 6.99 (s, 2H), 2.67 (m, 4H), 1.54 (m, 4H), 1.23 ( m, 36H), 0.88 (m, 6H)

(E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) thiophen-2-yl) ethene ((E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) Synthesis of thiophen-2-yl) ethene)

(E) -1,2-bis (3-dodecylthiophen-2-yl) ethene (5 g, 9.6 mmol) in a mixed solvent of tetrahydrofuran / hexane (volume ratio 2/1, 100 mL), 2 mol Cyclohexane with n-butyllithium (11 ml, 22 mmol), trimethyltin chloride (4.38 g, 22 mmol) in the same manner as in Preparation Example 2 (E) -1,2-bis (3-dode Sil-5- (trimethylstannyl) thiophen-2-yl) ethene was obtained (5.2 g, yield: 63%). ¹ H NMR (300 MHz, CDCl ₃ ) [ppm] δ 7.05 (d, 2H), 6.99 (s, 2H), 2.67 (m, 4H), 1.54 (m, 4H), 1.23 (m, 36H), 0.88 ( m, 6H), 0.36 (s, 18H).

Preparation Example 4 (E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) thiophen-2-yl) ethene ((E) -1,2-bis (3-dodecyl- Synthesis of 5- (trimethylstannyl) thieno [3,2-b] thiophen-2-yl) ethene)

(E) -1,2-bis (3-dodecylthieno [3,2-b] thiophen-2-yl) ethene ((E) -1,2-bis (3-dodecylthieno [3,2 -b] thiophen-2-yl) ethene)

3-dodecylthieno [3,2- b ] thiophene-2-carbaldehyde (17 g, 50 mmol), tetrahydrofuran (THF) (250 mL), titanium (IV) chloride (6.5 mL) , (E) -1,2-bis (3-dodecylthieno [3,2-b] thiophen-2-yl as the target compound in the same manner as in Preparation Example 1 using zinc powder (7.8 g) ) Ethene was obtained (24 g, yield: 75%). ¹ H NMR (300 MHz, CDCl ₃ ) [ppm] δ 7.18 (d, 2H), 7.05 (d, 2H), 6.99 (s, 2H), 2.67 (m, 4H), 1.54 (m, 4H), 1.23 ( m, 36H), 0.88 (m, 6H)

(E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) thiophen-2-yl) ethene ((E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) thieno [3,2-b] thiophen-2-yl) ethene)

(E) -1,2-bis (3-dodecylthioeno [3,2-b] thiophen-2-yl) ethene (5 g, 9.6 mmol) in a mixed solvent of tetrahydrofuran / hexane (volume ratio 2/1, 100 mL), cyclohexane with 2 moles of n-butyllithium (11 ml, 22 mmol), trimethyltin chloride (4.38 g, 22 mmol) in the same manner as in Preparation Example 2 (E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) thiophen-2-yl) ethene was obtained (5.2 g, yield: 63%). ¹ H NMR (300 MHz, CDCl ₃ ) [ppm] δ 7.05 (d, 2H), 6.99 (s, 2H), 2.67 (m, 4H), 1.54 (m, 4H), 1.23 (m, 36H), 0.88 ( m, 6H), 0.36 (s, 18H).

Preparation Example 5 Synthesis of 13-Bromomethyl-heptacosane

Triphenylphosphine (60.56 g, 0.2308 mol) was dissolved in methylene chloride (MC) in a 500 mL three-neck round bottom flask, and the temperature was lowered to 0 ° C. and bromine (35.67 g, 0.2231 mol) was dropped ( dropping) and stir for 10 minutes. Then, 2-dodecylhexadecane-1-ol (33.0 g, 0.0803 mol) dissolved in methylene chloride (MC) was dropped and stirred for 16 hours. Extracted with methylene chloride (MC), the organic layer was washed with water, dried over MgSO ₄ and the solvent was removed using a rotary evaporator. Dissolve the remaining organic layer in hexane and filter the filtered part with nucleic acid continuously to dissolve the material as much as possible. The solvent dissolved in hexane was removed using a rotary evaporator. After separation by column chromatography using n -hexane solvent, the target compound 13-bromomethyl-heptacoic acid was obtained (15.56 g, 17.22%). ¹ H-NMR (300 MHz, CDCl ₃ ): δ 3.47-3.45 (m, 2H), 1.61-156 (d, 1H), 1.44-1.2 (m, 49H), 0.92-0.87 (t, 6H); EI, MS m / z (%): 473.6 (100, M +)

Production Example 6 3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-dodecylhexadecyl) -2,5-dihydro-pyrrolo [3,4 -c] pyrrole-1,4 (2H, 5H) -dione (3,6-Bis- (5-bromo-thiophen-2-yl) -2,5-bis- (2-dodecylhexadecyl) -2,5 -dihydro-pyrrolo [3,4-c] pyrrole-1,4-dione)

2,5-bis (2-dodecylhexadecyl) -3,6-di-thiophen-2-yl-2,5-dihydro-pyrrolo [3,4-c] pyrrole-1,4-da Synthesis of ions (2,5-Bis- (2-dodecylhexadecyl) -3,6-di-thiophen-2-yl-2,5-dihydro-pyrrolo [3,4-c] pyrrole-1,4-dione)

In a flask, 3,6-di (thiophen-2-yl) pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H) -dione (3.38 g, 0.011 mol) and K ₂ CO ₃ ( Add 6.22 g, 0.045 mol), dissolve in DMF (70 ml), raise the temperature to 155 ° C. and stir for 6 hours. Then 13-bromomethyl-heptacoic acid (Preparation Example 2, 32.0 g, 0.067 mol) was added in portions and stirred for 16 hours under a stream of nitrogen. Extract with diethyl ether and then add magnesium sulfate (MgSO ₄ ) to remove water and filter. Separation by column chromatography using Hexane / Methylene Chloride (MC) (1: 3) solvent and target compound 2,5-bis (2-dodecylhexadecyl) -3,6-di-thiophene 2-yl-2,5-dihydro-pyrrolo [3,4-c] pyrrole-1,4-dione was obtained (1.2 g, yield: 10.6%). ¹ HNMR (CDCl ₃ , 300 MHz) [ppm]: δ 8.89-8.88 (d, 2H), 8.65-8.64 (d, 2H), 7.29-7.28 (d, 2H), 3.96-3.93 (d, 4H), 1.91-186 (m, 2H), 1.31-1.25 (m, 96H), 0.92-0.90 (t, 12H); EI, MS m / z (%): 1085.84 (100, M < + >).

3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-dodecylhexadecyl) -2,5-dihydro-pyrrolo [3,4-c] pyrrole- 1,4 (2H, 5H) -dione (3,6-Bis- (5-bromo-thiophen-2-yl) -2,5-bis- (2-dodecylhexadecyl) -2,5-dihydro-pyrrolo [ 3,4-c] pyrrole-1,4-dione)

2,5-bis (2-dodecylhexadecyl) -3,6-di-thiophen-2-yl-2,5-dihydro-pyrrolo [3,4-c] pyrrole-1,4 in the flask -Dione (1.0 g, 0.92 mmol) is dissolved in chloroform (60mL) and the light is blocked with aluminum foil. Then slowly add dropwise NBS (N-bromosuccinimide; 0.34 g. 1.88 mmol) and stir for 8 hours. Extraction with MC, the organic layer was washed with water, dried over MgSO ₄ and the solvent was removed using a rotary evaporator. Separation by column chromatography using n- Hexane / EA (15: 1) solvent and recrystallization with MC and Hexane to obtain the target compound 3,6-bis (5-bromothiophen-2-yl) -2,5 Obtain Bis (2-dodecylhexadecyl) -2,5-dihydro-pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H) -dione (0.75 g, Yield: 65% ). ¹ HNMR (CDCl ₂ , 300 MHz) [ppm]: δ 8.65-8.64 (d, 2H), 7.29-7.28 (d, 2H), 3.96-3.93 (d, 4H), 1.91-186 (m, 2H ), 1.31-1.25 (m, 96H), 0.92-0.90 (t, 12H); EI, MS m / z (%): 1243.64 (100, M < + >).

Example 1 Synthesis of PDPPDBTE

The polymer may be polymerized through a Stille coupling reaction. 3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-decyltetradecyl) pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H)- Dione (0.50 g, 0.0004 mol) and (E) -1,2-bis (5- (trimethylstannyl) thiophen-2-yl) ethene (Preparation Example 1, 0.229 g, 0.0004 mmol) were added to chlorobenzene ( 5 mL) and carry out nitrogen substitution. After that, Pd ₂ (dba) ₃ (0.008 mg, 2 mol%) and P (o-tol) ₃ (0.011 g, 8 mol%) were added as a catalyst and refluxed at 100 ° C. for 48 hours. The reaction solution is then slowly precipitated in methanol (300 mL) and the resulting solids are filtered off. The filtered solid is purified in the order of methanol, hexane, toluene and chloroform through soxxlet. The down liquid was precipitated again in methanol, filtered through a filter and dried to give PDPPDBTE, the title compound as a dark green solid (90% yield). Mn = 34,000, polydispersity 1.78, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 6.99-6.83 (broad, 6H), 3.88 (broad, 4H), 2.11 (m 2H), 1.31-1.25 (m, 76H), 1.04-0.88 (m, 12H).

Example 2 Synthesis of PDPPDBTE12

The polymer may be polymerized through a Stille coupling reaction. 3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-decyltetradecyl) pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H)- Dione (0.50 g, 0.0004 mol), (E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) thiophen-2-yl) ethene (Preparation Example 3, 0.378 g, 0.0004 mmol ), Pd ₂ (dba) ₃ (0.008 mg, 2 mol%) and P (o-tol) ₃ (0.011 g, 8 mol%) were used to obtain the title compound PDPPDBTE12 in the same manner as in Example 1 Yield: 90%). Mn = 90,000, polydispersity 1.8, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 7.1-6.99 (broad, 4H), 3.88 (broad, 4H), 2.11 (m 2H), 1.40-1.25 (m, 120H), 1.04-0.88 (m, 18H).

Example 3 Synthesis of PDPPBTPE

The polymer may be polymerized through a Stille coupling reaction. 3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-decyltetradecyl) pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H)- Dione (0.50 g, 0.0004 mol), (E) -1,2-bis (4- (trimethylstannyl) phenyl) ethene (Preparation Example 2, 0.202 g, 0.0004 mmol), Pd ₂ (dba) ₃ (0.008 mg, 2 mol%) and P (o-tol) ₃ (0.011 g, 8 mol%) were used to obtain the title compound PDPPBTPE in the same manner as in Example 1 (yield: 90%). Mn = 90,000, polydispersity 1.8, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 7.7 (broad, 8H), 6.99 (S, 2H), 3.88 (broad, 4H ), 2.11 (m 2 H), 1.31-1.25 (m, 76H), 1.04-0.88 (m, 12H).

Example 4 Synthesis of PDPPDTTE12

The polymer may be polymerized through a Stille coupling reaction. 3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-decyltetradecyl) pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H)- Dione (0.50 g, 0.0004 mol), (E) -1,2-bis (3-dodecyl-5- (trimethylstannyl) thiophen-2-yl) ethene (Preparation Example 4, 0.39 g, 0.0004 mmol ), The title compound PDPPDTTE12 was obtained in the same manner as in Example 1 using Pd ₂ (dba) ₃ (0.008 mg, 2 mol%) and P (o-tol) ₃ (0.011 g, 8 mol%) ( Yield: 75%). Mn = 45,000, polydispersity 1.7, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 7.1-6.99 (broad, 4H), 3.88 (broad, 4H), 2.11 (m 2H), 1.40-1.25 (m, 120H), 1.04-0.88 (m, 18H).

Example 5 Synthesis of PDPPDBTA

The polymer may be polymerized through Suzuki coupling. Remove water from the flask and remove 2,5-bis (2-decyltetradecyl) -3,6-bis (5- (4,4,5,5-tetramethyl-1,3,2-dioxaborolane- 2-yl) thiophen-2-yl) pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H) -dione (1.20 g, 0.0010 mol) and (E) -2,3-bis Add (5-bromothiophen-2-yl) acrylonitrile (0.367g, 0.0010 mmol), add 2M K ₂ CO ₃ (2.94 mL) and toluene (12 mL), and perform nitrogen bubbling for 30 minutes. do. Add catalyst Pd (pph ₃ ) ₄ (0.057 mg, 5 mol%) and reflux at 100 ° C. for 48 hours. The solution is then slowly precipitated in methanol (300 mL) and the solids are filtered off. The filtered solid is purified in the order of methanol, hexane, toluene and chloroform through soxxlet. The down liquid was precipitated again in methanol, filtered through a filter and dried to precipitate to obtain PDPPDBTA, the title compound as a dark green solid (yield: 90%). Mn = 20,000, polydispersity 1.68, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 6.99-6.83 (broad, 5H), 3.88 (broad, 4H), 2.11 (m 2H), 1.31-1.25 (m, 76H), 1.04-0.88 (m, 12H).

Example 6 Synthesis of PDPPBDTPA

The polymer may be polymerized through Suzuki coupling. Remove water from the flask and remove 2,5-bis (2-decyltetradecyl) -3,6-bis (5- (4,4,5,5-tetramethyl-1,3,2-dioxaborolane- 2-yl) thiophen-2-yl) pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H) -dione (0.5 g, 0.0004 mol), (Z) -2,3-bis (4-bromo-2,5-dimethylphenyl) acrylonitrile (0.367 g, 0.0004 mmol), 2M K ₂ CO ₃ (1.17 mL), toluene (5 mL), catalyst Pd (pph ₃ ) ₄ (0.023 mg, 5 mol%) was used to obtain the title compound PDPPBDTPA in the same manner as in Example 5 (yield: 80%). Mn = 18,000, polydispersity 1.87, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 7.2-6.83 (broad, 5H), 3.88 (broad, 2H), 2.34-2.11 (m 16H), 1.31-1.25 (m, 124H), 1.04-0.88 (m, 24H).

Example 7 Synthesis of PDPPDTDTEP

The polymer may be polymerized through a Stille coupling reaction. 3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-decyltetradecyl) pyrrolo [3,4-c] pyrrole-1,4 (2H, 5H)- Dione (0.50 g, 0.0004 mol), 2- (4-((E) -2- (3-dodecyl-5- (trimethylstannyl) thiophen-2-yl) vinyl) -2,5-di Methylstyryl) -3-dodecyl-5- (trimethylstannyl) thiophene (0.39 g, 0.0004 mmol), Pd ₂ (dba) ₃ (0.008 mg, 2 mol%) and P (o-tol) ₃ ( 0.011 g, 8 mol%) was used to obtain the title compound PDPPDTDTEP (yield: 75%) in the same manner as in Example 1. Mn = 55,000, polydispersity 1.7, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 7.1-6.99 (broad, 4H), 3.88 (broad, 4H), 2.11 (m 2H), 1.40-1.25 (m, 120H), 1.04-0.88 (m, 18H).

Example 8 Synthesis of P28DPP-TVT

The polymer may be polymerized through a Stille coupling reaction. 3,6-bis3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-dodecylhexadecyl) -2,5-dihydro-pyrrolo [3,4 -c] pyrrole-1,4 (2H, 5H) -dione (Preparation Example 6, 0.30 g, 0.92 mmol) and (E) -1,2-bis (5- (trimethylstannyl) thiophen-2- Il) ethene (Preparation Example 1, 0.13 g, 0.92 mmol) is dissolved in chlorobenzene (4.5 mL) and subjected to nitrogen substitution. Thereafter, Pd ₂ (dba) ₃ (0.004 g, 2 mol%) and P (o-tol) ₃ (0.0061 g, 8 mol%) were added as a catalyst and refluxed at 100 ° C. for 48 hours. The reaction solution is then slowly precipitated in methanol (300 mL) and the resulting solids are filtered off. The filtered solid is purified in the order of methanol, hexane, toluene and chloroform through soxxlet. The down liquid was precipitated again in methanol, filtered through a filter and dried to give the title compound P28DPP-TVT as a dark green solid (83% yield). Mn = 83,800, Mw = 110,300, polydispersity 1.31, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 6.99-6.83 (broad, 6H), 3.98-3.93 (broad, 4H), 2.05-1.86 (m 2H), 1.31-1.26 (m, 96H), 0.99-0.90 (m, 12H).

Example 9 Synthesis of P32DPP-TVT

The polymer may be polymerized through a Stille coupling reaction. 3,6-bis3,6-bis (5-bromothiophen-2-yl) -2,5-bis (2-tetradecyloctadecyl) -2,5-dihydro-pyrrolo [3,4 -c] pyrrole-1,4 (2H, 5H) -dione (0.40 g, 0.29 mmol) and (E) -1,2-bis (5- (trimethylstannyl) thiophen-2-yl) ethene ( Preparation Example 1, 0.15 g, 0.29 mmol) was dissolved in chlorobenzene (6 mL) and subjected to nitrogen substitution. After that, Pd ₂ (dba) ₃ (0.004 g, 2 mol%) and P (o-tol) ₃ (0.0071 g, 8 mol%) were added as a catalyst and refluxed at 100 ° C. for 48 hours. The reaction solution is then slowly precipitated in methanol (300 mL) and the resulting solids are filtered off. The filtered solid is purified in the order of methanol, hexane, toluene and chloroform through soxxlet. The down liquid was precipitated again in methanol, filtered through a filter and dried to give the title compound P32DPP-TVT as a dark green solid (73% yield). Mn = 97,000, Mw = 128,500, polydispersity 1.32, ¹ H NMR (300 MHz, CDCl ₃ ) [ppm]: δ 8.93 (broad, 4H), 6.99-6.83 (broad, 6H), 3.98-3.93 (broad, 4H), 2.05-1.86 (m 2H), 1.31-1.22 (m, 104H), 0.96-0.90 (m, 12H).

Example 10 Fabrication of Organic Electronic Device

The OTFT device was fabricated in a top-contact manner, 100 nm n-doped silicon was used as a gate, and SiO ₂ was used as an insulator. Surface treatment was performed by using a piranha cleaning solution (H ₂ SO ₄ : 2H ₂ O ₂ ) to wash the surface, Alfa's ODTS (octadecyltrichlorosilane) surface was used after SAM (Self Assemble Monolayer) treatment. The organic semiconductor layer was coated with 0.2 wt% chloroform solution using a spin-coater for 1 minute at 2000 rpm. As the organic semiconductor material, PDPPDBTE, P28DPP-TVT, or P32DPP-TVT synthesized in Examples 1, 8, and 9, respectively, were used. The thickness of the organic semiconductor layer was confirmed as 50 nm using a surface profiler (Alpha Step 500, Tencor). Gold used as the source and drain was deposited at a thickness of 60 nm at 1 A / s. The channel is 100 μm long and 1000 μm wide. Keithley 4800 was used to measure the properties of the OTFT.

The charge mobility of the organic electronic device manufactured in Example 10 was obtained from the slope of the graph with (I _SD ) ^1/2 and V _G as variables from the following saturation region current equation.

Where I _SD is the source-drain current, μ or μ _FET is the charge mobility, C ₀ is the oxide capacitance, W is the channel width, L is the channel length, V _G is the gate voltage, and V is _T is the threshold voltage. In addition, the cutoff leakage current I _off is a current flowing in the off state, and is determined as the minimum current in the off state in the current ratio.

The light absorption regions of the organic semiconductor compounds (PDPPDBTE, P28DPP-TVT, P32DPP-TVT) synthesized in Examples 1, 8, and 9 were measured in a solution state (solution: CHCl ₃ ) and in a film state. 4 is shown. To analyze the electrochemical properties of the organic semiconductor compounds (PDPPDBTE, P28DPP-TVT, P32DPP-TVT) synthesized in Examples 1, 8 and 9, 50 mV / in a solvent (Acetonitrile) of Bu ₄ NClO ₄ (0.1 molarity) 5 to 7 show the results measured using cyclic voltammetry with a cycle under the condition of s. Voltage was applied through the coating using a carbon electrode during the measurement.

Table 1 below describes the optical and electrochemical properties of the organic semiconductor compounds synthesized in Examples 1, 8 and 9 (PDPPDBTE, P28DPP-TVT, P32DPP-TVT). Here, the HOMO value is a value calculated using the result value measured in FIGS. 5 to 7. In addition, the band gap was obtained from the UV absorption wavelength in the film state. As shown in Table 1, the bandgap is similar and the oxidation stability is similar or slightly increased, the oxidation level is similar or slightly increased as the carbon number of the alkyl group is increased, the organic semiconductor compounds of Examples 1, 8 and 9 It can be seen that the oxidation stability is excellent.

Table 1

Polymer	Optical properties			Electrochemical properties
Polymer	UVλ_max ^sol(nm)	UVλ_max ^film(nm)	UV-edge (nm)	Band gap (optical) (eV)	Oxidation onset (eV)	E_HOMO (eV)	E_LUMO (eV)
PDPPDBTE (Example 1)	780	796	968	1.28	0.85	-5.31	-4.03
P28DPP-TVT (Example 8)	778	802	955	1.29	0.86	-5.32	-4.03
P32DPP-TVT (Example 9)	799	799	952	1.30	0.88	-5.34	-4.04

8 to 10, thermal stability of the organic semiconductor compounds (PDPPDBTE, P28DPP-TVT, and P32DPP-TVT) synthesized in Examples 1, 8, and 9 were measured. In PDPPDBTE, the glass transition temperature was measured at 260 ° C. The melting temperature was measured at 277 ° C. and the crystallization temperature was measured at 261 ° C., indicating that the crystal had a qualitative characteristic. In addition, in P28DPP-TVT, the melting temperature value (T _m ) was measured at 286 ° C. and the crystallization temperature value was measured at 258 ° C., indicating that the crystal had a qualitative characteristic. In addition, in P32DPP-TVT, a melting peak was observed around 280 ° C, indicating that the thermal properties were excellent.

11 to 13 illustrate results obtained by measuring decomposition temperatures of organic semiconductor compounds (PDPPDBTE, P28DPP-TVT, and P32DPP-TVT) synthesized in Examples 1, 8, and 9 using TGA. The temperature at which 5% decomposition of PDPPDBTE occurs was measured at 421 ° C, the temperature at which 5% decomposition of P28DPP-TVT occurs at 433 ° C, and the temperature at which 5% decomposition of P32DPP-TVT occurs at 391 ° C. Both P28DPP-TVT and P32DPP-TVT have excellent thermal stability.

In FIG. 14, a distribution state of electrons according to energy levels of molecules is illustrated through DFT calculation. In the HOMO energy level of the organic semiconductor compound (PDPPDBTE) synthesized in Example 1, it can be seen that electrons are spread throughout the molecular structure. In the LUMO energy level, it can be seen that the electrons of the electron donor move toward the electron acceptor, and the result shows that the charge separation of the energy is performed well.

In FIG. 15, AFM images of the device fabricated in Example 10 using the organic semiconductor compound (PDPPDBTE) synthesized in Example 1 (a: at room temperature, b: annealed film at 200 ° C.), c: Fig. 1 shows the state of the film annealed at 250 ° C.), and the crystallinity of the molecule is increased after annealing.

16 to 21 are diagrams showing the transfer curve of the device fabricated in Example 10 using the organic semiconductor compound (PDPPDBTE, P28DPP-TVT, P32DPP-TVT) synthesized in Examples 1, 8 and 9, the polymer material It is a figure showing the characteristics of the organic electronic device. As shown in FIGS. 16 to 21, the organic semiconductor compound synthesized in the present invention has excellent thermal stability, and it can be seen that the charge mobility increases when annealing is an excellent material.

Table 2 below describes the characteristics of the device fabricated in Example 10 using the organic semiconductor compounds synthesized in Examples 1, 8, and 9 (PDPPDBTE, P28DPP-TVT, P32DPP-TVT). At annealing temperature of 200 ° C., the charge mobility (increased from 1.32 → 2.62 → 2.65) and the flashing ratio (1.53 × 10 ⁴ → 2.78 × 10 ⁴ ) are increased as the carbon number of the alkyl group substituted in the organic semiconductor compound is increased. → 7.54 x 10 ⁴ )), and especially when the alkyl group of 28 and 32 carbon atoms, it was confirmed that the similar or somewhat improved charge mobility and improved flashing ratio.

TABLE 2

Polymer	Heat treatment	Surface modification	Mobility (cm ² / (V s))	Flashing ratio on / off ratio
PDPPDBTE (Example 1)	200 ℃	ODTS	1.32	1.53 x 10 ⁴
P28DPP-TVT (Example 8)	200 ℃	ODTS	2.62	2.78 x 10 ⁴
P32DPP-TVT (Example 9)	200 ℃	ODTS	2.65	7.54 x 10 ⁴

As a comparative compound, a diketopyrrolopyrrole polymer having the following structure was used (J. Am. Chem. Soc. 2011, 133, 10364-10367).

Using the comparative compound P (DPP-alt-QT) OTFT device was manufactured in the same top-contact manner as in Example 10.

That is, in the diketopyrrolopyrrole polymer of the present invention, alkyl having 24 or more carbon atoms is introduced at the nitrogen atom of the diketopyrrolopyrrole group, while the comparative compound P (DPP-alt-QT) is a diketopyrrole. Alkyl having 20 carbon atoms is introduced into the nitrogen atom of the pyrrole group, and the charge mobility is only about 30 to 40%, which is significantly lower than the embodiment of the present invention, proving the superiority of the present invention. In addition, when the alkyl having 24 or more carbon atoms is introduced as in the present invention, it has a good solubility and has a relatively high molecular weight and is relatively well dissolved, so that the solution process is smoother than that of the comparative compound P (DPP-alt-QT). Will be lost.

In addition, in the diketopyrrolopyrrole polymer of the present invention, a vinylene group is necessarily introduced between thiophene and thiophene, while the comparative compound P (DPP-alt-QT) has a structure in which thiophene and thiophene are connected by a single bond. to be. Accordingly, the diketopyrrolopyrrole polymer of the present invention can form a longer conjugated structure due to the vinylene group, thereby making the intermolecular interaction relatively larger, thereby making the polymer more rich in electron density. Such a structure and the bonding with a substituent having 24 or more carbon atoms bonded to the nitrogen atom has the effect of having a remarkable charge mobility.

The present invention surprisingly improved in unexpected charge mobility, thermal stability, solubility characteristics, oxidation stability, threshold voltage and flashing ratio when the carbon number of the alkyl group substituted at the nitrogen atom of the diketopyrrolopyrrole group to 24 or more It was completed by confirming the effect for the first time, and furthermore, the cause is unknown. However, when the carbon number of the alkyl group is adjusted to 28 or more, the charge mobility, the flashing ratio, and the solubility characteristics of the alkyl group may be improved. In addition, the charge mobility is improved by more than two times compared to the case of the alkyl group having 24 carbon atoms, the first recognition that the surprising effect was achieved.

The organic semiconductor compound according to the present invention, that is, a diketopyrrolopyrrole polymer configured to alternately polymerize a compound containing a diketopyrrolopyrrole derivative as an electron acceptor compound and a vinylene group as an electron donor compound is mainly introduced by the introduction of a vinylene group. By increasing the coplanarity of the chain and having an expanded conjugated structure, the electron density is improved, thereby increasing the intermolecular interaction and showing excellent thermal stability. In addition, the organic semiconductor compound according to the present invention is a polymer having 24 or more carbon atoms in the nitrogen atom of the diketopyrrolopyrrole group has excellent solubility characteristics and larger molecular weight, it is easily applied to the solution process. In addition, the HOMO value decreases, that is, the electron density increases in the repeating unit, thereby having excellent charge mobility and oxidation stability, and thus may be used as an organic semiconductor layer of the organic thin film transistor. Therefore, the organic thin film transistor employing these devices improves the charge mobility and the flashing ratio, and when the organic thin film transistor is used, it is possible to make an electronic device having excellent efficiency and performance. The organic thin film transistor can also be manufactured by a solution process such as vacuum deposition, spin coating, or printing, thereby reducing the manufacturing cost of an electronic device using the organic thin film transistor.

Claims

Diketopyrrolopyrrole polymer represented by the following formula (1).

[Formula 1]

[In Formula 1,

R 1 and R 2 are each independently (C 24 -C 50) alkyl;

L 1 and L 2 are each independently selected from the following structures;

V is
ego;

A 1 and A 2 are each independently hydrogen, cyano or -COOR ';

R 'is (C1-C50) alkyl or (C6-C50) aryl;

R 3 to R 8 are each independently hydrogen, hydroxy group, amino, (C1-C50) alkyl, (C6-C50) aryl, (C1-C50) alkoxy, mono or di (C1-C50) alkylamino, (C1- C50) alkoxycarbonyl or (C1-C50) alkylcarbonyloxy;

m is an integer of 1 or 2, and when m is 2, each of V and L 2 may be the same or different from each other; And

n is an integer from 1 to 1,000.]
The method of claim 1,

remind
Is a diketopyrrolopyrrole polymer, characterized in that selected from the following structure.

[The above A 1 , A 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are the same as defined in claim 1.]
The method of claim 2,

remind
Is a diketopyrrolopyrrole polymer, characterized in that selected from the following structure.
The method of claim 1,

R 1 and R 2 are each independently (C 28 -C 50) alkyl diketopyrrolopyrrole polymer.
The method of claim 1,

Diketopyrrolopyrrole polymer, characterized in that selected from the following compounds.

[Wherein n is an integer of 1 to 1,000.]
The method of claim 5,

Diketopyrrolopyrrole polymer, characterized in that selected from the following compounds.

[Wherein n is an integer of 1 to 1,000.]
The method of claim 6,

Diketopyrrolopyrrole polymer, characterized in that selected from the following compounds.

[Wherein n is an integer of 1 to 1,000.]
An organic thin film transistor comprising the diketopyrrolopyrrole polymer according to any one of claims 1 to 7 in an organic semiconductor layer.