Full-printing film patterning method

Abstract

The invention belongs to the technical field of semiconductor display device preparation, and particularly relates to a method for patterning a full-printing film layer. According to the method, printing and solution coating are combined, printing is carried out only in partial areas in a large area, coating is carried out on most areas in the large area, full-printing film patterning is achieved, the process time is short, the process takt is high, and expensive equipment is not needed. Moreover, the method provided by the invention has no pollution risk on the film layer interface, can protect the interface characteristics of the film layer surface, and ensures the electrical properties of the device.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor display device preparation, and in particular relates to a method for patterning a full-printed film layer. Background Art

[0002] As display technology continues to develop towards high resolution, high performance and low cost, thin film transistors (TFTs) play an important role as the core components of display screens. Compared with the traditional vacuum evaporation method, the full solution method for preparing thin film transistors reduces energy consumption and cost. The preparation of thin film transistors is achieved through self-assembly or chemical reaction of material molecules in the solution on the substrate. In addition, the full solution method is expected to achieve the preparation of larger area display screens to meet the growing market demand. At the same time, various functional materials can be easily introduced during the preparation process of the full solution method to optimize and regulate the performance of thin film transistors.

[0003] At present, in the process of preparing thin film transistors by all-solution method, there are two main schemes to realize the patterning of each film layer of the device: the first scheme adopts the traditional photolithography method, and the specific process is as follows: Figure 1 As shown, the target pattern is obtained by coating photoresist on the substrate, pre-baking, exposing, developing and post-baking, and then etching the film layer. The second solution adopts the printing method. The specific process is as follows Figure 2 As shown, the film layer solution is directly printed to the designated area through a nozzle, and then the printed solution is cured at high temperature, so that direct and fixed-point preparation of the film layer patterning can be achieved.

[0004] However, since the full solution method has a large printing area for the film layer, especially the insulating layer and other film layers, which are only opened at the electrical contact holes, and the rest of the area is coated on the entire surface, in order to ensure the printing accuracy and quality of the printed film layer, the printing time is long, resulting in a low process cycle. Summary of the invention

[0005] The purpose of the present invention is to provide a method for patterning a full-printed film layer, and the method provided by the present invention has a high process cycle.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides a method for patterning a fully printed film layer, comprising the following steps:

[0008] Printing a hydrophobic pattern on the surface of a substrate using a hydrophobic solution and then curing the printed pattern to obtain a hydrophobic pattern substrate;

[0009] A hydrophilic dielectric layer solution is coated on the surface of the hydrophobic pattern substrate and then heated to obtain a dielectric layer substrate.

[0010] Preferably, the substrate is a substrate with a metal electrode array.

[0011] Preferably, the hydrophobic solution comprises one or both of a fluorinated polyester solution and a polyacrylic acid solution; and the concentration of the hydrophobic solution is 1 to 30 wt%.

[0012] Preferably, the printing resolution is 5 to 10 mL / drop, and the printing thickness is 50 to 1000 nm.

[0013] Preferably, when the substrate is a substrate with a metal electrode array, the printing position is at the center of a single metal electrode in the metal electrode array; the distance between the center point of the hydrophobic pattern and the edge of the metal electrode below it is 10 to 500 μm.

[0014] Preferably, the hydrophobic pattern is a contact hole array; the thickness of the hydrophobic pattern is 20 to 1000 nm.

[0015] Preferably, the curing temperature is 60-150° C., and the heat preservation curing time is 1-60 min; and the curing is carried out on a hot plate.

[0016] Preferably, the coating is spin coating; the spin coating is full-surface spin coating; the spin coating rotation speed is 200-3000 rpm, the spin coating time is 15-120 s; the number of spin coating is 1-10 times; the target total thickness of the spin coating is 50-300 nm.

[0017] Preferably, the hydrophilic dielectric layer solution comprises an aluminum hafnium oxide solution; and the concentration of the hydrophilic dielectric layer solution is 0.05-1.0 mol / L.

[0018] Preferably, the heating temperature is 250-650° C., and the heating time is 3-90 min.

[0019] The present invention provides a method for patterning a fully printed film layer. The present invention combines printing with solution coating, and only a part of the area in a large area is printed, and most of the area is coated, thereby achieving fully printed film layer patterning, short process time, high process cycle, and no need for expensive equipment. In addition, the method provided by the present invention has no risk of contamination to the film layer interface, can protect the interface characteristics of the film layer surface, and ensure the electrical performance of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 Process flow chart for achieving full solution film patterning using traditional photolithography methods;

[0022] Figure 2 Process flow chart for achieving full solution film patterning using traditional printing methods;

[0023] Figure 3 A process flow chart of full-printed film patterning provided by the present invention;

[0024] Figure 4 A schematic diagram of a hydrophobic first contact hole prepared in Example 1 of the present invention;

[0025] Figure 5 Schematic diagram of coating the entire surface with a hydrophilic dielectric layer solution according to Example 1 of the present invention;

[0026] Figure 6 A schematic diagram of forming a dielectric layer and decomposing a first contact hole to form a second contact hole according to Embodiment 1 of the present invention;

[0027] Figure 7 This is a graph showing the capacitance-voltage characteristic of the dielectric layer in Test Example 1 of the present invention;

[0028] Reference numerals: 1 is a substrate, 2 is a first contact hole, 3 is a second contact hole, 4 is a coated hydrophilic dielectric layer solution, and 5 is a dielectric layer. DETAILED DESCRIPTION

[0029] The present invention provides a method for patterning a fully printed film layer, comprising the following steps:

[0030] Printing a hydrophobic pattern on the surface of a substrate using a hydrophobic solution and then curing the printed pattern to obtain a hydrophobic pattern substrate;

[0031] A hydrophilic dielectric layer solution is coated on the surface of the hydrophobic pattern substrate and then heated to obtain a dielectric layer substrate.

[0032] The present invention uses a hydrophobic solution to print a hydrophobic pattern on the surface of a substrate and then solidifies it to obtain a hydrophobic pattern substrate. In the present invention, the substrate is preferably cleaned before use; the standard of the cleaning is preferably that the water contact angle is less than 15 degrees; the cleaning is preferably: brush cleaning, glass cleaning liquid cleaning, ultrasonic cleaning, high-pressure water cleaning and nitrogen purging of the substrate in sequence; the cleaning equipment is preferably a glass cleaning machine.

[0033] In the present invention, the substrate is preferably a substrate with a metal electrode array.

[0034] In the present invention, the hydrophobic solution preferably includes one or both of a fluorinated polyester solution (PVDF-HFP) and a polyacrylic acid solution; the concentration of the hydrophobic solution is preferably 1 to 30 wt%, specifically 3 wt%, 10 wt% or 20 wt%.

[0035] In the present invention, the printing resolution is preferably 5-10 mL / drop, specifically 5 mL / drop, 6 mL / drop, 7 mL / drop, 8 mL / drop, 9 mL / drop or 10 mL / drop, and the printing thickness is preferably 50-1000 nm, specifically 50 nm, 100 nm, 200 nm, 300 nm, 500 nm, 700 nm, 850 nm or 1000 nm.

[0036] In the present invention, when the substrate is a substrate with a metal electrode array, the printing position is preferably at the center of a single metal electrode in the metal electrode array; the distance between the center point of the hydrophobic pattern and the edge of the metal electrode below it is preferably 10 to 500 μm, specifically 10 μm, 20 μm, 50 μm, 100 μm, 200 μm, 300 μm, 400 μm or 500 μm.

[0037] In the present invention, the hydrophobic pattern is preferably a contact hole array; the thickness of the hydrophobic pattern is preferably 20 to 1000 nm, specifically 20 nm, 50 nm, 100 nm, 250 nm, 500 nm, 750 nm or 1000 nm. The present invention can produce patterns of different sizes and shapes according to needs, and the contact hole array exposes the metal electrode array on the substrate.

[0038] In the present invention, the curing temperature is preferably 60-150°C, specifically 60°C, 80°C, 100°C, 120°C or 150°C, the heat preservation curing time is preferably 1-60min, specifically 1min, 5min, 10min, 15min, 30min, 45min or 60min; the curing is preferably carried out on a hot plate. The present invention volatilizes the solvent in the hydrophobic solution through curing to form a hydrophobic pattern.

[0039] After obtaining the hydrophobic pattern substrate, the present invention coats the hydrophilic dielectric layer solution on the surface of the hydrophobic pattern substrate and then heats it to obtain a dielectric layer substrate. In the present invention, the coating is preferably spin coating; the spin coating is preferably full-surface spin coating; the spin coating speed is preferably 200-3000rpm, specifically 200rpm, 500rpm, 1000rpm, 1500rpm, 2000rpm, 2500rpm or 3000rpm, the spin coating time is preferably 15-120s, specifically 15s, 30s, 50s, 70s, 90s, 100s or 120s; the number of spin coatings is preferably 1-10 times, specifically 3 times or 7 times; the target total thickness of the spin coating is preferably 50-300nm, specifically 150nm or 250nm; the spin coating equipment is preferably a gel coater.

[0040] The present invention coats a layer of hydrophilic dielectric solution on the entire surface of the substrate and the hydrophobic pattern by coating. Since the hydrophilicity of the dielectric solution and the hydrophobic pattern are different, the dielectric solution cannot be adsorbed on the surface of the hydrophobic pattern and flows to the substrate area, thereby ensuring that the hydrophobic pattern area is not covered by the dielectric layer.

[0041] In the present invention, the hydrophilic dielectric layer solution preferably includes hafnium aluminum oxide solution (HfAlO); the concentration of the hydrophilic dielectric layer solution is preferably 0.05-1.0 mol / L, specifically 0.1 mol / L, 0.3 mol / L, 0.5 mol / L or 0.8 mol / L.

[0042] In the present invention, the heating temperature is preferably 250-650°C, specifically 250°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C or 650°C, and the heating time is preferably 3-90 minutes, specifically 3 minutes, 5 minutes, 10 minutes, 20 minutes, 30 minutes, 50 minutes, 60 minutes, 70 minutes or 90 minutes. The present invention, by heating, on the one hand, cures the hydrophilic dielectric layer solution to form a dielectric layer, and on the other hand, completely decomposes the hydrophobic pattern on the substrate, exposing the underlying material.

[0043] In the present invention, the thickness of the dielectric layer on the dielectric layer substrate is preferably 50-1000 nm, and specifically may be 50 nm, 100 nm, 200 nm, 500 nm, 800 nm or 1000 nm.

[0044] The method for patterning a fully printed film provided by the present invention has a main process flow as follows: Figure 3After cleaning the substrate, the present invention uses a hydrophobic solution to print a hydrophobic pattern on the surface of the substrate, and then solidifies it to obtain a hydrophobic pattern substrate; then a hydrophilic dielectric layer solution is coated on the surface of the hydrophobic pattern substrate, and then heated to form a dielectric layer, while the hydrophobic pattern is completely decomposed, the lower layer material is exposed, and the dielectric layer substrate is successfully prepared.

[0045] In order to further illustrate the present invention, the scheme of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments, but they should not be understood as limiting the protection scope of the present invention.

[0046] Example 1

[0047] (1) The substrate with the metal electrode array is placed in a glass cleaning machine and cleaned in sequence by a brush, glass cleaning fluid, ultrasonic wave and high-pressure water, and then purged with nitrogen gas.

[0048] (2) On the surface of the substrate, a 3wt% fluorinated polyester solution was printed on the central area of ​​each metal electrode surface, with a printing resolution of 5mL / drop and a printing thickness of 300nm to form a contact hole array, wherein the distance between the center point of the contact hole array pattern and the edge of the metal electrode thereunder was 60μm; the substrate was placed on a hot plate at 120°C and cured for 15min to obtain a hydrophobic first contact hole, as shown in FIG. Figure 4 As shown, the thickness of the first contact hole is 250 nm.

[0049] (3) The entire surface of the substrate and the first contact hole was spin-coated by a coating machine, and a HfAlO solution with a concentration of 0.3 mol / L was used as the dielectric layer solution. The dielectric layer film was obtained by spin coating three times at a speed of 1000 rpm, and the film thickness was 150 nm. Figure 5 As shown in the figure, the spin coating time is 30s each time. Due to the different hydrophilicity between the HfAlO solution and the first contact hole, the HfAlO solution cannot form a film on the surface of the first contact hole, while the HfAlO solution can cover other areas on the substrate surface. The HfAlO solution is baked at 600℃ for 60min to completely solidify the HfAlO solution, completely decompose the PVDF-HFP film, and expose the metal electrode. Figure 6 As shown, a dielectric layer substrate is obtained.

[0050] Test Example 1

[0051] The dielectric properties of Example 1 were tested using a capacitance-voltage characteristic parameter instrument. The test frequency was 100kHz and the voltage test range was -1V to 1V. The results are as follows: Figure 7 shown.

[0052] according to Figure 7It can be seen that at an annealing temperature of 600°C, the unit capacitance of the HfAlO dielectric film is 84nF / cm 2 , the film has good dielectric properties.

[0053] It can be seen from the above embodiments that the method provided by the present invention has a short process time, a high process cycle, does not require expensive equipment, has good dielectric properties of the film layer, and ensures the electrical performance of the device.

[0054] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for patterning a fully printed film layer, characterized in that: The following steps are involved: Printing a hydrophobic pattern on the surface of a substrate using a hydrophobic solution and then curing the printed pattern to obtain a hydrophobic pattern substrate; A hydrophilic dielectric layer solution is coated on the surface of the hydrophobic pattern substrate and then heated to obtain a dielectric layer substrate.

2. The method according to claim 1, characterized in that The substrate is a substrate with a metal electrode array.

3. The method according to claim 1, characterized in that The hydrophobic solution comprises one or both of a fluorinated polyester solution and a polyacrylic acid solution; the concentration of the hydrophobic solution is 1 to 30 wt %.

4. The method according to claim 1 or 3, characterized in that: The printing resolution is 5-10 mL / drop, and the printing thickness is 50-1000 nm.

5. The method according to claim 1 or 2, characterized in that: When the substrate is a substrate with a metal electrode array, the printing position is at the center of a single metal electrode in the metal electrode array; the distance between the center point of the hydrophobic pattern and the edge of the metal electrode below it is 10 to 500 μm.

6. The method according to claim 1 or 3, characterized in that: The hydrophobic pattern is a contact hole array; the thickness of the hydrophobic pattern is 20-1000 nm.

7. The method according to claim 1 or 3, characterized in that: The curing temperature is 60-150° C., and the heat preservation curing time is 1-60 minutes; the curing is carried out on a hot plate.

8. The method according to claim 1, characterized in that The coating is spin coating; the spin coating is full-surface spin coating; the spin coating rotation speed is 200-3000 rpm, the spin coating time is 15-120 s; the number of spin coating is 1-10 times; the target total thickness of the spin coating is 50-300 nm.

9. The method according to claim 1 or 8, characterized in that: The hydrophilic dielectric layer solution includes an aluminum hafnium oxide solution; the concentration of the hydrophilic dielectric layer solution is 0.05-1.0 mol / L.

10. The method according to claim 1, characterized in that The heating temperature is 250-650° C., and the heating time is 3-90 minutes.

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