CN109872951A - A kind of preparation method of thin film transistor (TFT) polyimide gate insulating layer - Google Patents
A kind of preparation method of thin film transistor (TFT) polyimide gate insulating layer Download PDFInfo
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- CN109872951A CN109872951A CN201910108205.4A CN201910108205A CN109872951A CN 109872951 A CN109872951 A CN 109872951A CN 201910108205 A CN201910108205 A CN 201910108205A CN 109872951 A CN109872951 A CN 109872951A
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Abstract
The present invention relates to a kind of preparation methods of thin film transistor (TFT) polyimide gate insulating layer, comprising: (1) after cleaning up conductive substrates, high-purity argon gas drying is stand-by after oxygen gas plasma processing；(2) polyimides organic solution and silane coupler solution are prepared respectively；(3) in the conductive substrates after silane coupler solution to be spun to plasma treatment, heat treatment obtains silane coupling agent treated conductive substrates；(4) polyimides organic solution is spun to silane coupling agent treated in conductive substrates, vacuum heat treatment to get.The present invention solves the problems, such as that insulating layer is difficult to be in close contact with grid when preparing polyimide gate insulating layer thin film transistor (TFT), improves the flatness of polyimide insulative layer, reduces the preparation cost of polyimide gate insulating layer thin film transistor (TFT).
Description
Technical field
The invention belongs to polymeric gate insulation layer thin film transistor (TFT) preparation field, in particular to a kind of thin film transistor (TFT) is poly-
The preparation method of acid imide gate insulating layer.
Background technique
Flexible thin-film transistor is due to having the characteristics that flexible, the simple and suitable large area processing of preparation process, integrated
There is huge application prospect in the fields such as circuit, FPD and wearable device.In flexible thin-film transistor, insulating layer pair
The mechanical performance and electric property of device play key effect.
Currently, insulating layer material can be broadly divided into two major classes, inorganic material and using macromolecule as the organic material of representative.Phase
Than in inorganic insulating material, organic insulating material has preferably flexible and machinability.But organic insulator also has
Drawback, common organic insulating material seriously limit most if the fusing point of polymethyl methacrylate is generally not more than 140 DEG C
The application field and working environment of end organ part.Polyimides is a kind of organic insulating material that heat resistance is fabulous, and high temperature resistant is reachable
400 DEG C, be a kind of ideal thin film transistor (TFT) insulating layer material.But polyimides thermal expansion coefficient with higher, therefore
Kapton is heated in film forming procedure, due to the presence of internal stress, easily occurs going out between Kapton and substrate
Existing warpage, fracture and delamination and other issues (" polymer material science and engineering ", 2015,31 (10): 115-119).For solution
Certainly this problem, researcher generally start with from MOLECULE DESIGN, such as change the molecular structure of polyimides, reduce its thermal expansion system
Number, the planarization of Lai Tigao Kapton and its with the associativity of substrate (" modern plastics processed and applied ", 2018,30
(1): 16-18).Likewise, in the preparation process that polyimides does the film transistor device of insulating layer, due to polyimides
With biggish thermal expansion coefficient, therefore in the preparation process of device, when being prepared in particular by solwution method, easily occur exhausted
The deformation of edge layer film, the final interface cohesion for influencing insulating layer and electrode material, or even there is interfacial separation.Therefore final system
The yields of standby obtained polyimide insulative layer film transistor device is lower, and the device that majority is prepared can not normal work
Make.To solve this problem, researcher generally uses two-step method to prepare polyimide gate insulating layer, i.e., prepares first corresponding
Polyimide acid film, high-temperature cross-linking is carried out to it later, obtains Kapton.This method takes a long time, and institute
Need crosslinking temperature higher.In addition to this, insulating layer thermal deformation and solvent volatilization comprehensive function under, surface of insulating layer it is smooth
Degree is general lower, has seriously affected the electric property of final film transistor device.Thus, how to solve the above problems, develops
Obtain having the polyimide insulative layer thin film transistor (TFT) of excellent properties to receive the extensive concern of researcher.
Summary of the invention
Technical problem to be solved by the invention is to provide a kind of preparations of thin film transistor (TFT) polyimide gate insulating layer
Method, it is low to overcome the existing polyimide gate insulating layer thin film transistor (TFT) success rate for preparing, and insulating layer and grid are difficult to closely
Contact, the low defect of surface of insulating layer flatness.
A kind of preparation method of thin film transistor (TFT) polyimide gate insulating layer of the invention, comprising:
(1) after cleaning up conductive substrates, high-purity argon gas drying, oxygen gas plasma processing obtains plasma treatment
Conductive substrates afterwards；
(2) polyimide powder is dissolved in n,N-dimethylacetamide, is vigorously stirred, obtain concentration be 200~
The polyimides organic solution of 300mg/mL；It is water-soluble that silane coupling agent according to 5~10% mass percent is dissolved in ethyl alcohol
In liquid, is acutely stood after concussion, obtain silane coupler solution；
(3) silane coupler solution in step (2) is spun to the conductive substrates in step (1) after plasma treatment
On, heat treatment obtains silane coupling agent treated conductive substrates；
(4) the polyimides organic solution in step (2) is spun to silane coupling agent in step (3) treated and is conductive
It in substrate, is heat-treated under vacuum, obtains thin film transistor (TFT) polyimide gate insulating layer.
Conductive substrates in the step (1) are indium oxide tin glass or tin oxide glass.
The purity of high-purity argon gas is 99.999% or more in the step (1).
The process conditions that conductive substrates are cleaned in the step (1) are as follows: successively clear with ultrapure water, acetone, isopropanol ultrasound
Wash 10~20min.
The technological parameter that oxygen gas plasma is handled in the step (1) are as follows: radio-frequency power is 300~500W, when processing
Between be 5~10min.
Silane coupling agent is aminopropyl triethoxysilane, chloromethyl triethoxysilane or ammonia third in the step (2)
Base trimethoxy silane.
The volume fraction of ethyl alcohol is 95~98% in ethanol water in the step (2).
The process conditions being vigorously stirred in the step (2) are as follows: in closed container room temperature be vigorously stirred 12~for 24 hours.
The process conditions stood in the step (2) are as follows: be stored at room temperature 1~6h.
The technological parameter of spin coating in the step (3) are as follows: spin coating rate be 3000~5000r/min, spin-coating time be 1~
2min, spin coating acceleration are 1000~1500r/s2。
Process of thermal treatment parameter in the step (3) are as follows: heat treatment environment is air, and heat treatment temperature is 100~150
DEG C, heat treatment time is 1~2h.
The technological parameter of spin coating in the step (4) are as follows: spin coating rate be 6000~7000r/min, spin-coating time be 1~
2min, spin coating acceleration are 800~1000r/s2。
Process of thermal treatment parameter under vacuum in the step (4) are as follows: vacuum degree is 0.1MPa and hereinafter, heat treatment temperature
It is 100~120 DEG C, heat treatment time is 24~48h.
A kind of thin film transistor (TFT) high-flatness polyimide gate insulating layer of any description above, makes in air environment
It is standby, do not need control humidity.
The present invention chooses silane coupling agent as binder, uses the organic solution of polyimides as raw material, use is molten
The method of liquid spin coating realizes the cladding of high-flatness Kapton in conductive substrates, to be used for subsequent thin film crystal
The preparation of tube device.The present invention uses oxygen plasma processing method first, and upper hydroxyl reactive group is grafted in conductive substrates.
Silane coupling agent is fully hydrolyzed in ethanol water later, is coated in conductive substrates.Under the action of heat content, conductive base
Chemical bond is generated between the silane coupling agent after hydroxyl and hydrolysis on bottom.Last coating polyimide solution, silane coupling agent
With polyimides under Van der Waals force and hydrogen bond force effect, combine closely.Therefore, silane coupling agent is as binder by conductive base
Bottom and polyimide insulative layer tight bond.
Beneficial effect
The present invention using silane coupling agent as binder, by conductive substrates and polyimide insulative layer tight bond,
The polyimide insulative layer of high-flatness is prepared in conductive substrates.This preparation method, which solves, prepares polyimides grid
Insulating layer and grid are difficult to the problem of being in close contact when insulating layer of thin-film transistor, reduce polyimide gate insulating layer film
The preparation cost of transistor improves the flatness of polyimide insulative layer, improves that prepare polyimide gate insulating layer thin
The success rate of film transistor device.
Detailed description of the invention
Fig. 1 is the device schematic diagram that the present invention prepares thin film transistor (TFT) high-flatness polyimide gate insulating layer, wherein
1- conductive substrates；2- silane coupling agent；3- Kapton.
Fig. 2 is the optical profilometer micrograph of polyimide gate insulating layer in embodiment 1.
Fig. 3 is the optical profilometer micrograph of polyimide gate insulating layer in comparative example 1.
Specific embodiment
Present invention will be further explained below with reference to specific examples.It should be understood that these embodiments are merely to illustrate the present invention
Rather than it limits the scope of the invention.In addition, it should also be understood that, after reading the content taught by the present invention, those skilled in the art
Member can make various changes or modifications the present invention, and such equivalent forms equally fall within the application the appended claims and limited
Range.
The polycondensation monomer of raw materials used polyimide powder is 2,2'- bis- (trifluoromethyl) diamino in the embodiment of the present invention
Biphenyl and hexafluorodianhydride (6FDA), molecular weight are about 5.2 × 104.The model KH550 of silane coupling agent, purity are that analysis is pure.
Embodiment 1
(1) it successively uses ultrapure water, acetone, isopropanol to be cleaned by ultrasonic 10min in indium zinc oxide glass, then uses
99.999% argon gas drying, handles 5min under the conditions of radio-frequency power 300W using oxygen gas plasma later, obtain etc. from
Conductive substrates after subprocessing.
(2) polyimide powder is dissolved in n,N-dimethylacetamide, carries out being vigorously stirred 12h in closed container,
Obtain the polyimides organic solution of 200mg/mL.
(3) aminopropyl triethoxysilane silane coupling agent is dissolved in volume fraction of ethanol according to 95% mass ratio is
In 95% ethanol water, 1h acutely is stood after concussion at room temperature, obtains silane coupler solution.
(4) using the silane coupler solution in dropper aspiration step (3), step is spun to according to the rate of 3000r/s
(1) in the conductive substrates in after plasma treatment, spin-coating time 1.5min, spin coating acceleration is 1200r/s2, air environment
In be heat-treated 1h at 100 DEG C, obtain silane coupling agent treated conductive substrates；
(5) using the polyimides organic solution in dropper aspiration step (2), step is spun to according to the rate of 6000r/s
Suddenly in (4) in silane coupling agent treated conductive substrates, spin-coating time 1.5min, spin coating acceleration is 900r/s2, vacuum
100 DEG C of heat treatments for 24 hours, obtain thin film transistor (TFT) high-flatness polyimide gate insulating layer under conditions of degree is 0.1MPa.
Embodiment 2
(1) it successively uses ultrapure water, acetone, isopropanol to be cleaned by ultrasonic 10min in indium zinc oxide glass, then uses
99.999% argon gas drying, handles 5min under the conditions of radio-frequency power 300W using oxygen gas plasma later, obtain etc. from
Conductive substrates after subprocessing.
(2) polyimide powder is dissolved in n,N-dimethylacetamide, carries out being vigorously stirred 12h in closed container,
Obtain the polyimides organic solution of 200mg/mL.
(3) aminopropyl triethoxysilane silane coupling agent is dissolved in volume fraction of ethanol according to 95% mass ratio is
In 95% ethanol water, 1h acutely is stood after concussion at room temperature, obtains silane coupler solution.
(4) using the silane coupler solution in dropper aspiration step (3), step is spun to according to the rate of 3500r/s
(1) in the conductive substrates in after plasma treatment, spin-coating time 1.5min, spin coating acceleration is 1200r/s2, air environment
In be heat-treated 1h at 100 DEG C, obtain silane coupling agent treated conductive substrates；
(5) using the polyimides organic solution in dropper aspiration step (2), step is spun to according to the rate of 6000r/s
Suddenly in (4) in silane coupling agent treated conductive substrates, spin-coating time 1.5min, spin coating acceleration is 900r/s2, vacuum
100 DEG C of heat treatments for 24 hours, obtain thin film transistor (TFT) high-flatness polyimide gate insulating layer under conditions of degree is 0.1MPa.
Embodiment 3
(1) it successively uses ultrapure water, acetone, isopropanol to be cleaned by ultrasonic 10min in indium zinc oxide glass, then uses
99.999% argon gas drying, handles 5min under the conditions of radio-frequency power 300W using oxygen gas plasma later, obtain etc. from
Conductive substrates after subprocessing.
(2) polyimide powder is dissolved in n,N-dimethylacetamide, carries out being vigorously stirred 12h in closed container,
Obtain the polyimides organic solution of 200mg/mL.
(3) aminopropyl triethoxysilane silane coupling agent is dissolved in volume fraction of ethanol according to 95% mass ratio is
In 95% ethanol water, 1h acutely is stood after concussion at room temperature, obtains silane coupler solution.
(4) using the silane coupler solution in dropper aspiration step (3), step is spun to according to the rate of 3000r/s
(1) in the conductive substrates in after plasma treatment, spin-coating time 1.5min, spin coating acceleration is 1200r/s2, air environment
In be heat-treated 1h at 100 DEG C, obtain silane coupling agent treated conductive substrates；
(5) using the polyimides organic solution in dropper aspiration step (2), step is spun to according to the rate of 6000r/s
Suddenly in (4) in silane coupling agent treated conductive substrates, spin-coating time 1.5min, spin coating acceleration is 900r/s2, vacuum
120 DEG C of heat treatments for 24 hours, obtain thin film transistor (TFT) high-flatness polyimide gate insulating layer under conditions of degree is 0.1MPa.
Comparative example 1
The method that tradition prepares thin film transistor (TFT) polyimide gate insulating layer does not use silane coupling agent, poly- in order to overcome
The presoma polyimide acid of polyimides the problem of deformation, is prepared film forming first in thermal histories by acid imide, right later
It carries out high-temperature process, brings it about crosslinking, finally obtains Kapton.Polyimide acid used in this comparative example by
2,2'- bis- (trifluoromethyl) benzidines and hexafluorodianhydride (6FDA) are low in n-methyl-2-pyrrolidone solvent according to a certain percentage
Warm polycondensation forms, and used in polyimides preparation process used in the content and embodiment of two kinds of monomers in polyimide acid
Amount of monomer is identical.
Specific preparation method, comprising:
(1) it successively uses ultrapure water, acetone, isopropanol to be cleaned by ultrasonic 10min in indium zinc oxide glass, then uses
99.999% argon gas drying, handles 5min under the conditions of radio-frequency power 300W using oxygen gas plasma later, obtain etc. from
Conductive substrates after subprocessing.
(2) polyimide powder is dissolved in n,N-dimethylacetamide, carries out being vigorously stirred 12h in closed container,
Obtain the polyimides organic solution of 200mg/mL.
(3) using the polyimides organic solution in dropper aspiration step (2), step is spun to according to the rate of 6000r/s
Suddenly in the conductive substrates in (1) after plasma treatment, spin-coating time 1.5min, spin coating acceleration is 1200r/s2, vacuum degree
To be heat-treated for 24 hours under conditions of 0.1MPa 100 DEG C, polyimide acid film is obtained.
(4) under conditions of vacuum degree is 0.1MPa, 300 DEG C of high temperature are carried out to the polyimide acid film in step (3)
2h is handled, thin film transistor (TFT) polyimide gate insulating layer can be obtained.
The optical profilometer micrograph of the thin film transistor (TFT) polyimide gate insulating layer of embodiment 1 and comparative example 1 is distinguished
As shown in Figures 2 and 3, as can be seen that the flatness of the polyimide gate insulating layer of embodiment 1 from optical profilometer micrograph
Higher than the polyimide gate insulating layer in comparative example 1, or even there is apparent interference wave, also illustrates that its flatness is high.
Claims (9)
1. a kind of preparation method of thin film transistor (TFT) polyimide gate insulating layer, comprising:
(1) after conductive substrates being cleaned up, high-purity argon gas drying, oxygen gas plasma processing, after obtaining plasma treatment
Conductive substrates；
(2) polyimide powder is dissolved in n,N-dimethylacetamide, is vigorously stirred, obtaining concentration is 200~300mg/
The polyimides organic solution of mL；Silane coupling agent is dissolved in ethanol water according to 5~10% mass percent, it is acute
Violent shock is stood after swinging, and obtains silane coupler solution；
(3) silane coupler solution in step (2) is spun in the conductive substrates in step (1) after plasma treatment, heat
Processing obtains silane coupling agent treated conductive substrates；
(4) the polyimides organic solution in step (2) is spun to silane coupling agent in step (3) treated conductive substrates
On, it is heat-treated under vacuum, obtains thin film transistor (TFT) polyimide gate insulating layer.
2. according to the method described in claim 1, it is characterized by: the conductive substrates in the step (1) are tin indium oxide glass
Glass or tin oxide glass；The purity of high-purity argon gas is 99.999% or more.
3. according to the method described in claim 1, it is characterized by: the process conditions that conductive substrates are cleaned in the step (1)
Are as follows: successively it is cleaned by ultrasonic 10~20min with ultrapure water, acetone, isopropanol；The technological parameter of oxygen gas plasma processing are as follows: penetrate
Frequency power is 300~500W, and the processing time is 5~10min.
4. according to the method described in claim 1, it is characterized by: silane coupling agent is three second of aminopropyl in the step (2)
Oxysilane, chloromethyl triethoxysilane or aminopropyl trimethoxysilane；The volume fraction of ethyl alcohol is in ethanol water
95~98%.
5. according to the method described in claim 1, it is characterized by: the process conditions being vigorously stirred in the step (2) are as follows:
In closed container room temperature be vigorously stirred 12~for 24 hours；The process conditions of standing are as follows: be stored at room temperature 1~6h.
6. according to the method described in claim 1, it is characterized by: in the step (3) spin coating technological parameter are as follows: spin coating speed
Rate is 3000~5000r/min, and spin-coating time is 1~2min, and spin coating acceleration is 1000~1500r/s2。
7. according to the method described in claim 1, it is characterized by: process of thermal treatment parameter in the step (3) are as follows: at heat
Reason environment is air, and heat treatment temperature is 100~150 DEG C, and heat treatment time is 1~2h.
8. according to the method described in claim 1, it is characterized by: in the step (4) spin coating technological parameter are as follows: spin coating speed
Rate is 6000~7000r/min, and spin-coating time is 1~2min, and spin coating acceleration is 800~1000r/s2。
9. according to the method described in claim 1, it is characterized by: process of thermal treatment parameter under vacuum in the step (4)
Are as follows: vacuum degree is 0.1MPa and hereinafter, heat treatment temperature is 100~120 DEG C, and heat treatment time is 24~48h.
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| CN107148154A (en) * | 2017-07-12 | 2017-09-08 | 江南大学 | A kind of conducting wire typography based on inkjet printing |
| CN107431020A (en) * | 2015-03-27 | 2017-12-01 | 东丽株式会社 | The effective photosensitive polymer combination of film crystal, cured film, thin film transistor (TFT), liquid crystal display device or organic el display, the manufacture method of cured film, the manufacture method of thin film transistor (TFT) and the manufacture method of liquid crystal display device or organic el display |
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2019
- 2019-02-03 CN CN201910108205.4A patent/CN109872951A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2014170080A (en) * | 2013-03-01 | 2014-09-18 | Jsr Corp | Radiation-sensitive resin composition, insulating film, and organic el element |
| CN107431020A (en) * | 2015-03-27 | 2017-12-01 | 东丽株式会社 | The effective photosensitive polymer combination of film crystal, cured film, thin film transistor (TFT), liquid crystal display device or organic el display, the manufacture method of cured film, the manufacture method of thin film transistor (TFT) and the manufacture method of liquid crystal display device or organic el display |
| JP2017126728A (en) * | 2016-01-15 | 2017-07-20 | 東洋紡株式会社 | Method of manufacturing flexible electronic device |
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