CN113856237B

CN113856237B - Supercritical processing method for organic semiconductor device

Info

Publication number: CN113856237B
Application number: CN202110985897.8A
Authority: CN
Inventors: 张冠张; 李蕾; 刘凯
Original assignee: Peking University Shenzhen Graduate School
Current assignee: Peking University Shenzhen Graduate School
Priority date: 2021-08-26
Filing date: 2021-08-26
Publication date: 2023-01-03
Anticipated expiration: 2041-08-26
Also published as: CN113856237A

Abstract

The invention provides a supercritical processing method of an organic semiconductor device, which comprises the following steps: providing an organic semiconductor device and carbon dioxide; obtaining carbon dioxide in a supercritical state; and extracting impurities of the organic semiconductor device by using carbon dioxide in a supercritical state. Therefore, impurities in the structure of the organic material, such as small molecules of polymer monomer molecules, oligomers and the like or impurities of a soft cross-linking agent, can be removed from the organic material by carbon dioxide in a supercritical state. At the same time, water molecules are likewise removed from the organic material by carbon dioxide in the supercritical state. Therefore, the electrical properties of the organic material structure exerted in the organic semiconductor device can be further approximated to an ideal model, and the influence of impurities is reduced.

Description

Supercritical processing method for organic semiconductor device

Technical Field

The invention relates to the technical field of organic semiconductor devices, in particular to a supercritical processing method of an organic semiconductor device.

Background

In recent years, many organic materials are used to manufacture organic electronic devices to replace some traditional inorganic materials, so as to improve the performance of traditional devices, especially flexible organic semiconductor devices, organic solar cells, intelligent devices, and the like, which have the advantages of low manufacturing cost and easy manufacturing.

Organic materials (including organic semiconductor layers, organic electrodes, organic dielectrics, etc.) are generally prepared by solution processing methods, and generally include spin coating, dipping, ink-jet printing, and other processing steps. In the preparation process, the use of a solvent, and the presence of small molecular compounds such as polymer monomer molecules and oligomers adversely affect the electrical properties of the organic polymer semiconductor material. In addition, in some organic material implementations, corresponding impurities may also be introduced. If the organic polymer is prepared using a soft cross-linking agent, impurities of the soft cross-linking agent may be introduced into the material.

Generally, the saturated vapor pressure of the impurities is small, and the impurities are usually removed by conventional evaporation, but the method still leaves a large amount of impurities, which affects the performance of the organic semiconductor. In addition, organic polymer semiconductors are sensitive to high temperature and moisture, and may undergo chemical reactions such as decomposition and oxidation when exposed to high temperature, oxygen, and moisture, thereby affecting the material properties.

It is therefore desirable to find a method for removing impurities and moisture from organic semiconductors at low temperatures.

Disclosure of Invention

The invention mainly solves the technical problem that impurities and water vapor exist in an organic semiconductor device.

According to a first aspect, an embodiment provides a supercritical processing method for an organic semiconductor device, comprising:

providing an organic semiconductor device, a first substance and carbon dioxide;

subjecting the first substance to supercritical treatment so that the first substance is in a supercritical state, wherein the critical temperature T1 of the first substance is less than the critical temperature T2 of the carbon dioxide;

treating the carbon dioxide by a first substance in a supercritical state to obtain carbon dioxide in the supercritical state;

and extracting impurities of the organic semiconductor device by using carbon dioxide in a supercritical state.

According to a second aspect, an embodiment provides a supercritical processing method of an organic semiconductor device, comprising:

providing an organic semiconductor device and carbon dioxide;

obtaining carbon dioxide in a supercritical state;

According to the supercritical processing method of the organic semiconductor device of the embodiment, the organic semiconductor device and the carbon dioxide are provided; obtaining carbon dioxide in a supercritical state; and extracting impurities of the organic semiconductor device by using carbon dioxide in a supercritical state. Therefore, impurities in the structure of the organic material, such as small molecules of polymer monomer molecules, oligomers and the like or impurities of a soft cross-linking agent, can be removed from the organic material by carbon dioxide in a supercritical state. At the same time, water molecules are also removed from the organic material by the carbon dioxide in the supercritical state. Therefore, the electrical properties of the organic material structure exerted in the organic semiconductor device can be further approximated to an ideal model, and the influence of impurities is reduced.

Drawings

FIG. 1 is a schematic flow chart of a supercritical processing method for an organic semiconductor device according to an embodiment;

FIG. 2 is a schematic flow chart of a supercritical processing method for an organic semiconductor device according to another embodiment;

FIG. 3 is a schematic structural diagram of a capacitor device according to an embodiment;

fig. 4a and 4b are schematic structural diagrams of an organic semiconductor device supercritical processing apparatus according to an embodiment;

FIG. 5 is a schematic comparison of the film thickness test before and after the supercritical processing of the capacitor device according to an embodiment;

FIGS. 6, 7a and 7b are schematic diagrams illustrating comparison of capacitance characteristics of a capacitor device before and after supercritical processing according to an embodiment;

fig. 8a, fig. 8b and fig. 9 are schematic diagrams illustrating comparison of material analysis before and after supercritical processing of a capacitor device according to an embodiment.

Reference numerals: 10-a substrate; 20-a lower electrode; 30-a PMMA film; 40-an upper electrode; 100-a carbon dioxide supply source; 200-pneumatic pump; 300-a valve; 400-a reaction chamber; 401-a temperature regulating assembly; 500-a capacitive device; 600-carbon tetrafluoride supply source.

Detailed Description

The present invention will be described in further detail with reference to the following detailed description and accompanying drawings. Wherein like elements in different embodiments have been given like element numbers associated therewith. In the following description, numerous details are set forth in order to provide a better understanding of the present application. However, one skilled in the art will readily recognize that some of the features may be omitted or replaced with other elements, materials, methods in different instances. In some instances, certain operations related to the present application have not been shown or described in this specification in order not to obscure the core of the present application with unnecessary detail, and it is not necessary for those skilled in the art to describe these operations in detail, so that they may be fully understood from the description in the specification and the general knowledge in the art.

Furthermore, the features, operations, or characteristics described in the specification may be combined in any suitable manner to form various embodiments. Also, the various steps or actions in the description of the methods may be transposed or transposed in order, as will be apparent to a person skilled in the art. Thus, the various sequences in the specification and drawings are for the purpose of describing certain embodiments only and are not intended to imply a required sequence unless otherwise indicated where such sequence must be followed.

The numbering of the components as such, e.g., "first", "second", etc., is used herein only to distinguish the objects as described, and does not have any sequential or technical meaning. The term "connected" and "coupled" as used herein includes both direct and indirect connections (couplings), unless otherwise specified.

Example one

In the organic material structure of the organic semiconductor device, a preparation technology based on a solution processing method is generally adopted, and in the preparation process, impurities and water vapor are left in the organic material structure due to the use of a solvent and the existence of small molecular compounds such as polymer monomer molecules and oligomers, so that the electrical characteristics of the organic material structure are adversely affected.

Supercritical technology is gradually applied to traditional industrial production, such as extraction, particle manufacturing, environmental management, chemical reaction, energy conservation and the like. Taking supercritical extraction technology as an example, the extraction process mainly adopts supercritical carbon dioxide as an extraction solvent, and organic compounds can be extracted from plant seeds, fruits, leaves and other parts by utilizing the unique physical properties of a supercritical fluid. The application field of the supercritical fluid technology is wide, but the supercritical fluid principle is not thoroughly researched, the operating pressure of the supercritical fluid is high, and the requirement on equipment is high. Meanwhile, the manufacturing threshold of the semiconductor process is high, and the supercritical technology practitioners recognize the problems of the profession and the industry, so that the application of the supercritical technology in the semiconductor integrated circuit industry is always very limited.

As shown in fig. 1, an embodiment of the present invention provides a supercritical processing method for an organic semiconductor device, including:

step 1: an organic semiconductor device and carbon dioxide are provided.

The organic semiconductor device may be an organic semiconductor device that performs any one of processes from the preparation of an organic material structure to the completion of encapsulation, that is, may be a semi-finished product in the manufacturing process or a finished product after encapsulation.

Step 2: carbon dioxide in a supercritical state is obtained.

And step 3: and extracting impurities of the organic semiconductor device by using supercritical carbon dioxide.

And (3) placing the organic semiconductor device in supercritical carbon dioxide, and processing the organic material structure of the organic semiconductor device by using the supercritical carbon dioxide.

More specifically, the carbon dioxide in the supercritical state can permeate into the organic material structure of the organic semiconductor device by utilizing the permeability and the fluidity of the carbon dioxide in the supercritical state. The supercritical carbon dioxide has strong extraction capability for organic matters, particularly small molecular organic matters, which is fully proved in the extraction field. Therefore, impurities in the structure of the organic material, such as small molecules like polymer monomer molecules and oligomers or impurities of the soft cross-linking agent, can be removed from the organic material by carbon dioxide in a supercritical state. At the same time, water molecules are also removed from the organic material by the carbon dioxide in the supercritical state. Therefore, the electrical properties of the organic material structure exerted in the organic semiconductor device can be further approximated to an ideal model, and the influence of impurities is reduced.

The critical temperature of the carbon dioxide is 31.06 ℃, for example, when the processing temperature is 40 ℃, the ultimate working temperature of most organic semiconductor devices is more than 40 ℃, so the carbon dioxide in a supercritical state is adopted to process the organic semiconductor devices, and the organic semiconductor devices cannot be damaged at high temperature.

In a possible implementation manner, the obtaining of carbon dioxide in a supercritical state may include:

and performing supercritical treatment on the carbon dioxide to enable the carbon dioxide to be in a supercritical state, wherein the treatment temperature T is less than or equal to Tm, and Tm is the ultimate working temperature of the organic material structure or the organic semiconductor device.

For example, polymethyl methacrylate (PMMA) deforms at an ultimate working temperature of 80 ℃ and 90 ℃, and is generally used at a temperature of 70 ℃ or lower. Therefore, when an organic semiconductor device is processed using carbon dioxide in a supercritical state, the processing temperature cannot be higher than the limit operating temperature of the organic material structure. That is, when carbon dioxide is supercritical, the processing temperature should be lower than the limit operating temperature of the organic material structure.

In one practical application, the material of the organic material structure may be polymethyl methacrylate (PMMA). PMMA has excellent performances of good impact strength, transparency, high hydrophobicity, stability and the like. At present, PMMA can replace SiO2 to be used as a gate dielectric layer to obtain high-performance OTFTs, can be used as a switching layer of RRAM, shows good resistance switching characteristic and transfer characteristic, and is an organic material commonly used in organic semiconductor devices.

In one practical application, when the organic material is PMMA, the corresponding impurity is at least one of an organic impurity and water. For example, the organic impurities may be butyl acetate (BuAc) as a solvent and dibenzoyl peroxide (BPO) as an initiator. The solvent and the initiator are organic impurities which are difficult to avoid in the preparation process of the organic material structure, and the carbon dioxide in a supercritical state can remove the organic impurities and water from the organic material structure.

Example two

The existing substance supercritical method adopts a single means of temperature rise and pressure rise, and the realization of supercritical treatment also needs the substance to meet the conditions of high concentration and even purity.

Therefore, the existing supercritical technology has the following defects:

1. the supercritical method is single; 2. safety issues such as supercritical treatment of flammable or toxic fluids; 3. high energy consumption is needed for supercritical treatment of substances such as water, ammonia and the like; 4. supercritical material processing requires that it be highly concentrated or pure.

In the embodiment of the present invention, a method for realizing supercritical carbon dioxide by using a first substance in a supercritical state is provided on the basis of the first embodiment, and the method is applied to the supercritical processing method for an organic semiconductor device provided in the embodiment of the present invention. Among them, the supercritical treatment of carbon dioxide alone has at least one of the disadvantages of the above-mentioned conventional supercritical technology, such as the first point and the fourth point. By adopting the method provided by the embodiment of the invention, at least one problem can be solved. The supercritical processing method of the organic semiconductor device provided by the embodiment of the invention has more advantages.

In order to avoid the above limitations and realize the supercritical processing of substances such as carbon dioxide under lower temperature and pressure and safer conditions for impurity extraction of organic semiconductor devices, as shown in fig. 2, the supercritical processing method for organic semiconductor devices provided by the embodiment of the present invention may include:

step 10: an organic semiconductor device, a first material, and carbon dioxide are provided.

Step 20: and performing supercritical treatment on the first substance to enable the first substance to be in a supercritical state, wherein the treatment temperature T is more than or equal to T1, the treatment pressure P is more than or equal to P1, and the critical temperature T1 of the first substance is less than the critical temperature T2 of the carbon dioxide.

The processing temperature T and the processing pressure P may be temperatures and pressures for processing the organic semiconductor device. Under the conditions of temperature and pressure, the first substance is supercritical.

Step 30: and treating the carbon dioxide by the first substance in the supercritical state to obtain the carbon dioxide in the supercritical state.

Specifically, carbon dioxide and the supercritical first substance are introduced into one reaction chamber, wherein the order of introducing the carbon dioxide and the supercritical first substance into the reaction chamber is not limited, and after standing for a certain time, the carbon dioxide is dissolved in the supercritical first substance based on the fact that the supercritical fluid has high solubility and high permeability, and thus the carbon dioxide is subjected to supercritical treatment.

Step 40: and extracting impurities of the organic semiconductor device by using supercritical carbon dioxide.

Here, the carbon dioxide in a supercritical state refers to carbon dioxide dissolved in the first substance in a supercritical state. For example, when the organic semiconductor device is placed in a reaction chamber, carbon dioxide and the supercritical first substance are introduced, and after the carbon dioxide is subjected to supercritical treatment, the carbon dioxide in the supercritical state and the supercritical first substance simultaneously exist in the reaction chamber, only the carbon dioxide in the supercritical state can remove impurities from the organic material structure, and the supercritical first substance can play a role of a solvent or a protective gas. It is not excluded that there is a possibility that both the first and second species contribute to impurity extraction of the organic material structure.

Since the first substance needs to be supercritical at a high concentration, it is required that the first substance is nonflammable or even nontoxic in order to ensure safety. While supercritical is preferably achieved at lower temperature and pressure conditions, the first species is preferably a gas.

In practical applications, the first substance may be a saturated bond compound containing carbon, an inert gas, or nitrogen. The saturated bond compound containing carbon and inert gas have high chemical stability, are not easy to react with carbon dioxide, and are not easy to cause adverse effects on organic semiconductor devices. While nitrogen is also commonly used as a shielding gas.

For example, the first substance may be carbon tetrafluoride. The critical pressure of the carbon dioxide is 7.38MPa, and the critical pressure is 31.06 ℃; the critical pressure of the carbon tetrafluoride is 3.74MPa, and the critical temperature is-45.67 ℃. As another example, the critical temperature of nitrogen is-146.9 ℃. It can be seen that carbon tetrafluoride or nitrogen has a lower critical temperature and is a non-flammable, non-toxic gas. Carbon dioxide can be brought into a supercritical state at a temperature of less than 31.06 ℃ by using carbon tetrafluoride or nitrogen as the first substance.

In another practical application, considering that the ultimate operating temperature of the organic semiconductor device may be lower than the critical temperature of carbon dioxide, the first material may be selected under the following conditions without considering the safety of the first material and the carbon dioxide: the treatment temperature T is more than or equal to T1 and less than T2. The first material at this time is not limited to carbon tetrafluoride and may be, for example, ethylene (process temperature 9.2 ℃) or dinitrogen oxide (process temperature 3.65 ℃).

In one possible implementation, when supercritical carbon dioxide alone is achieved, the mass fraction or volume fraction of carbon dioxide in the reaction chamber is 100%. In the method provided by this embodiment, the carbon dioxide is dissolved in the supercritical first substance, and the closer the processing condition in the reaction chamber is to the critical condition of the carbon dioxide, the higher the solubility of the carbon dioxide in the supercritical first substance, that is, the higher the mass fraction or volume fraction of the carbon dioxide. When low concentrations of carbon dioxide are required for impurity extraction, the mass fraction of carbon dioxide may be less than or equal to 5%, or the volume fraction of carbon dioxide less than or equal to 5%.

EXAMPLE III

The following organic material is PMMA as an example, and the supercritical processing method for an organic semiconductor device provided in the embodiment of the present invention is further described, but the supercritical processing method for an organic semiconductor device provided in the embodiment of the present invention is not limited to this application example.

In order to simplify the testing difficulty and reduce the interference of other structures of the organic semiconductor device, PMMA is used as a dielectric layer to prepare a capacitor, and the capacitor device is used for replacing the organic semiconductor device to perform electrical testing and material analysis. The capacitor device has a simple structure, and is convenient for electrical analysis and material analysis.

Firstly, providing a capacitor device and carrying out characteristic test. As shown in fig. 3, there may be a capacitor device prepared by the steps of:

1. the substrate is prepared, for example, by using a glass plate as the substrate 10.

2. The lower electrode 20 is deposited by sputtering and may be made of molybdenum.

3. Spin coating and drying to obtain the PMMA film 30.

4. The upper electrode 40 is patterned by sputtering. The upper electrode 40 may be made of aluminum.

And secondly, treating the capacitor device by using supercritical carbon dioxide to remove impurities.

For example, the supercritical processing apparatus for organic semiconductor devices shown in fig. 4a is used for processing, and the following processing procedures are adopted:

1. the required carbon dioxide gas is charged into the pneumatic pump 200 through the carbon dioxide supply source 100, and then the pneumatic pump 200 is closed through the valve 300, and the carbon dioxide is pressurized above a critical condition, for example, and to 1500psi.

2. The capacitor device 500 is placed in the reaction chamber 400, and then the reaction chamber 400 is closed and heated to a temperature above the critical temperature of carbon dioxide, for example, 40 ℃ by the temperature adjustment assembly 401.

3. The valves 300 of the pneumatic pump 200 and the reaction chamber 400 are opened, and the carbon dioxide gas of the pneumatic pump 200 is introduced into the reaction chamber 400, so that the carbon dioxide in the reaction chamber 400 reaches the required temperature of 40 ℃ and pressure of 1500psi, and then enters the supercritical state.

4. Standing the reaction chamber 400 for a period of time at the temperature of 40 ℃ and the pressure of 1500psi to complete the supercritical treatment, and then performing cooling and pressure relief operation on the reaction chamber 400 to complete the supercritical treatment of the capacitor device 500 and complete impurity removal treatment.

And thirdly, performing characteristic test and analysis on the processed gallium nitride deep ultraviolet organic semiconductor device.

For example, the film thickness and capacitance of the capacitor device are tested and compared with the characteristics of the capacitor device before processing.

When the ultimate operating temperature of the organic material structure is lower than the critical temperature of carbon dioxide, or the concentration of carbon dioxide is required to be low, the organic semiconductor device supercritical processing equipment as shown in fig. 4b can be used for processing in the second step, and the following processing procedures are adopted:

1. the desired carbon tetrafluoride gas is charged into the pneumatic pump 200 through the carbon tetrafluoride supply source 600, the pneumatic pump 200 is then closed through the valve 300, and the carbon tetrafluoride is pressurized above critical conditions, such as and to 4MPa.

2. The capacitor device 500 is placed in the reaction chamber 400, the reaction chamber 400 is then closed, and the temperature is raised to a temperature above the critical temperature of carbon tetrafluoride by the temperature adjustment assembly 401, for example, to 20 ℃.

3. The valves 300 of the pneumatic pump 200 and the reaction chamber 400 are opened, the carbon tetrafluoride gas of the pneumatic pump 200 is introduced into the reaction chamber 400, the carbon dioxide in the reaction chamber 400 reaches the required temperature of 20 ℃ and pressure of 4MPa, and then enters the supercritical state, and the required carbon tetrafluoride gas is introduced into the reaction chamber 400 through the carbon dioxide supply source 100.

4. Standing the reaction chamber 400 for a period of time under the conditions of the temperature of 20 ℃ and the pressure of 4MPa to complete the supercritical treatment, then performing cooling and pressure relief operation on the reaction chamber 400 to complete the supercritical treatment of the capacitor device 500, and completing impurity removal treatment.

As shown in fig. 5 and 6, it can be seen that the thickness and capacitance of the PMMA thin film are almost unchanged after the impurity removal treatment by the supercritical fluid, and the capacitance is more stable in multiple measurements. PMMA also maintains the same constant dielectric constant and thickness according to the capacitance equation C = a epsilon/d. This indicates that the supercritical treatment did not damage the original structure of the PMMA film.

As shown in fig. 7a and 7b, it can be seen that after the impurity removal is performed by the supercritical treatment, the leakage current of the device is reduced. Furthermore, as shown in fig. 7b, the leakage current fitting result indicates that the conduction mechanism of the leakage current is changed from the hopping conduction mechanism to the schottky conduction mechanism. The hopping conduction is caused by the continuous presence of defects in the PMMA film. These defects are due to residual solvent (e.g., buAc) and initiator (e.g., BPO) in the PMMA film. Electrons can beat from one defect to the center of another, creating a large leakage current. Due to the high permeability and solubility of supercritical fluids (e.g., carbon dioxide), the solvent and initiator can be dissolved in the fluid and effectively removed from the PMMA film. Therefore, after the impurity removal treatment of the supercritical fluid, the defects in the PMMA film are greatly removed, and the conduction mechanism is converted into a Schottky emission mechanism with less defects.

As shown in fig. 8a, 8b and 9, it can be seen that the results show a significant decrease in C = O absorption of the ester at 1740cm "1. The absorption of C-O of diethyl ether at 1100cm-1 and C-O of ester at 1200cm-1 was also lower. The results of fig. 5 and 6 have demonstrated that the supercritical fluid treatment does not damage the original structure of the PMMA film, and therefore the absorption of the functional groups C = O and C — O bond is reduced because the solvent (e.g., buAc) and initiator (e.g., BPO) are reduced rather than PMMA. Furthermore, the reduction of impurities such as a decline at 751cm-1, which occurs only in the phenyl group, which is a typical bond of aromatic hydrocarbons present in the initiator, is more pronounced. In conclusion, the supercritical fluid impurity removal treatment greatly removes impurities such as residual solvents and initiators. These results are consistent with the reduction of leakage current and the improvement of PMMA insulation in fig. 7 a.

In summary, after the organic semiconductor device is treated by the supercritical carbon dioxide, the impurities in the organic material structure are successfully removed, the influence caused by the impurities in the organic material structure is reduced, the leakage current is reduced, and the electrical performance of the device is improved.

With reference to the above three embodiments, it can be seen that the supercritical processing method for an organic semiconductor device provided by the embodiment of the present invention has at least the following technical effects:

1. preparing at low temperature: the supercritical carbon dioxide has a critical temperature of 31.7 ℃, so that the supercritical carbon dioxide can be processed at 40 ℃ and is very friendly to organic materials which cannot resist high temperature. Carbon tetrafluoride can also be used as the first substance to achieve a lower carbon dioxide supercritical at a lower temperature, so that the organic semiconductor device is processed at a lower temperature.

2. High compatibility: taking a PMMA capacitor device as an example, the supercritical processing of the organic semiconductor device can be carried out in the middle and at the end of the manufacturing process because the supercritical fluid has the unique physical properties and high permeability and solubility, and has excellent process compatibility with the existing organic semiconductor manufacturing technology.

3. The universality is as follows: according to the organic semiconductor device which needs to be processed actually, the fluid type selected by the first material can be adjusted, a plurality of conditions such as processing temperature, pressure, time, fluid flow and the like can be adjusted during actual processing, and the optimal processing condition parameters can be searched through a plurality of experiments.

4. Environment-friendly and low-cost: the invention is based on the unique physical property of the supercritical fluid, compared with the traditional process manufacturing, has the advantages of simple process manufacturing and low cost, and can be set through conditions. Based on the non-toxic property of carbon dioxide and carbon tetrafluoride, the preparation method is non-toxic and environment-friendly.

The present invention has been described in terms of specific examples, which are provided to aid in understanding the invention and are not intended to be limiting. Numerous simple deductions, modifications or substitutions may also be made by those skilled in the art in light of the present teachings.

Claims

1. A supercritical processing method for an organic semiconductor device is characterized by comprising the following steps:

treating the carbon dioxide by the first substance in the supercritical state to obtain carbon dioxide in the supercritical state; the carbon dioxide in the supercritical state is carbon dioxide dissolved in the first substance in the supercritical state;

and extracting impurities of the organic semiconductor device by supercritical carbon dioxide.

2. The supercritical processing method for an organic semiconductor device according to claim 1, wherein the first substance is a saturated bond compound containing an element carbon or an inert gas or nitrogen.

3. The supercritical processing method for an organic semiconductor device according to claim 2, wherein the first substance is carbon tetrafluoride or nitrogen.

4. The supercritical processing method for an organic semiconductor device according to claim 1, wherein the first material is subjected to supercritical processing at a temperature T of T1. Ltoreq. T < T2.

5. The supercritical processing method for an organic semiconductor device according to claim 1, wherein the mass fraction of carbon dioxide is less than or equal to 5%, or the volume fraction of carbon dioxide is less than or equal to 5%.

6. The supercritical processing method for an organic semiconductor device according to claim 1, wherein the impurity extraction of the organic semiconductor device by carbon dioxide in a supercritical state comprises:

extracting impurities from the organic material structure of the organic semiconductor device by supercritical carbon dioxide;

the organic semiconductor device is an organic semiconductor device which completes any one process from the preparation of the organic material structure to the completion of packaging.

7. The supercritical processing method for an organic semiconductor device according to claim 6, wherein the material of the organic material structure is polymethyl methacrylate.

8. The supercritical processing method for an organic semiconductor device according to claim 1, wherein the impurity is at least one of an organic impurity and water.

9. The supercritical processing method of an organic semiconductor device according to claim 4, wherein the processing temperature T is T ≦ Tm, tm < T2, and Tm is the ultimate operating temperature of the organic semiconductor device.