Surface roughening method of indium tin oxide thin film
Through microwave plasma source technology, hydrogen radicals and oxygen radicals are used to roughen the surface of the indium tin oxide film, which solves the problem of incomplete or excessive roughening in the prior art, and improves the surface of the indium tin oxide film The applicability and controllability of the lower film layer are protected.
Patent Information
- Application Number
- CN202111247698.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-10-26
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2041-10-26
AI Technical Summary
The existing indium tin oxide film surface roughening technology has poor applicability and is difficult to control the degree of roughening, which can easily lead to incomplete or excessive roughening, and damage to the underlying film layer.
Using microwave plasma source technology, hydrogen radicals and oxygen radicals are generated by controlling the ratio and process conditions of oxygen to water vapor, which are used to reduce and oxide the surface of indium tin oxide film, thereby achieving surface roughening and controlling hydrogen freedom. The ratio of radicals and oxygen radicals and process time improve the controllability of the degree of coarseness.
The applicability and controllability of the surface roughening of the indium tin oxide film is improved, and the incomplete or excessive roughening of the coarse is avoided, and the lower film layer is protected, ensuring that the indium tin oxide film is sufficiently roughened without damage.
Smart Images
Figure CN113991038B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of semiconductor process technology, and in particular to a method for roughening the surface of an indium tin oxide film. Background Art
[0002] Indium tin oxide (ITO) film has excellent electrical conductivity and high visible light transmittance, and is widely used in organic light-emitting diode (OLED) devices as an anode and can also serve as a light-transmitting window. The luminous efficiency and life of the organic light-emitting diode can be improved by performing surface roughening, ion implantation, surface work function modulation, etc. on the indium tin oxide film used as the anode. In the prior art, the surface of the indium tin oxide film can be roughened by plasma bombardment, or the surface of the indium tin oxide film can be roughened by soaking a wafer prepared with the indium tin oxide film in a hydrochloric acid solution and etching the indium tin oxide film with the hydrochloric acid solution.
[0003] However, after the indium tin oxide film is patterned, plasma will bombard the lower film layer of the indium tin oxide film exposed after patterning, causing damage to the lower film layer of the indium tin oxide film, and the hydrochloric acid solution will contact the lower film layer of the indium tin oxide film exposed after patterning, causing corrosion to metal film layers such as silicon oxide or aluminum, titanium, etc. Therefore, the applicability of the existing surface roughening method of the indium tin oxide film is poor, and because the hydrochloric acid solution corrodes the indium tin oxide film at a fast speed, and the physical bombardment roughening takes a long time, the roughening degree is difficult to control, resulting in the indium tin oxide film surface being easily roughened incompletely or excessively after roughening. Summary of the invention
[0004] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes a method for roughening the surface of an indium tin oxide film, which can improve the applicability of roughening the surface of an indium tin oxide film and improve the controllability of the roughening degree.
[0005] In order to achieve the purpose of the present invention, a method for roughening the surface of an indium tin oxide film is provided, which is characterized by comprising:
[0006] In the preparation stage, the wafer prepared with the indium tin oxide thin film is placed in a process chamber using a microwave plasma source, oxygen and water vapor are introduced, and an atmosphere mixed with the oxygen and the water vapor is formed in the process chamber under a first process condition;
[0007] In the roughening stage, oxygen and water vapor are introduced, and under the second process conditions, the water vapor is dissociated to generate hydrogen free radicals, and the oxygen is dissociated to generate oxygen free radicals. The hydrogen free radicals are used to reduce the indium ions and tin ions in the indium tin oxide, and the oxygen free radicals are used to oxidize the reduced indium and tin. By controlling the ratio of the hydrogen free radicals to the oxygen free radicals, the surface of the indium tin oxide film is roughened.
[0008] Optionally, controlling the ratio of the hydrogen free radical to the oxygen free radical includes: controlling the ratio of the hydrogen free radical to the oxygen free radical by controlling the ratio of the oxygen to the water vapor, and the ratio of the oxygen to the water vapor is 5:1-8:1.
[0009] Optionally, the second process conditions include: the flow rate of the oxygen gas is 600 sccm-1000 sccm, and the flow rate of the water vapor is 100 sccm-150 sccm.
[0010] Optionally, the second process condition further includes:
[0011] The frequency of the microwave plasma source is 2.45 GHz, the power of the microwave plasma source is 900 W-1300 W; the vacuum degree in the process chamber is 900 mTorr-1200 mTorr; and the duration is 15 s-40 s.
[0012] Optionally, after the roughening stage, the method for roughening the surface of the indium tin oxide film further comprises:
[0013] In the oxidation stage, oxygen is introduced into the process chamber under the third process condition to dissociate the oxygen into oxygen free radicals, and the oxygen free radicals are used to combine with oxygen vacancies on the surface of the roughened indium tin oxide film.
[0014] Optionally, the third process condition includes: the flow rate of the oxygen gas is 600 sccm-1000 sccm.
[0015] Optionally, the third process condition also includes: the frequency of the microwave plasma source is 2.45 GHz, the power of the microwave plasma source is 900 W-1300 W; the vacuum degree in the process chamber is 900 mTorr-1200 mTorr; and the duration is 10 s-20 s.
[0016] Optionally, in the preparation stage, the wafer prepared with the indium tin oxide thin film is placed on a heating component in the process chamber, and the temperature of the wafer is heated to greater than or equal to 100° C. by the heating component.
[0017] Optionally, the first process conditions include: the temperature of the heating component is 220℃-250℃; the power of the microwave plasma source is 0W; the vacuum degree in the process chamber is 900mTorr-1200mTorr; the flow rate of the oxygen is 600sccm-1000sccm, and the flow rate of the water vapor is 100sccm-150sccm; and the duration is 15s-40s.
[0018] Optionally, before the preparation stage, the method for roughening the surface of the indium tin oxide film further comprises:
[0019] In the film-making stage, a front film layer is prepared on the wafer, and the wafer on which the front film layer is prepared is cleaned;
[0020] Preparing the indium tin oxide thin film on the wafer prepared with the front film layer;
[0021] Applying photoresist on the wafer prepared with the indium tin oxide thin film;
[0022] Covering the wafer coated with the photoresist with a desired mask plate, and exposing and developing the wafer coated with the photoresist to form a desired pattern;
[0023] Etching the wafer formed with the desired pattern to completely etch the indium tin oxide film on the wafer corresponding to the photoresist opening;
[0024] The photoresist is removed to form the ITO film having the desired pattern on the wafer.
[0025] The present invention has the following beneficial effects:
[0026] The surface roughening method of an indium tin oxide film provided by the present invention comprises the following steps: placing a wafer prepared with an indium tin oxide film in a process chamber in a preparation stage, and forming an atmosphere mixed with oxygen and water vapor in the process chamber, dissociating water vapor to generate hydrogen free radicals, and dissociating oxygen to generate oxygen free radicals in a roughening stage, reducing indium ions and tin ions in the indium tin oxide with the help of hydrogen free radicals, and oxidizing the reduced indium and tin with the help of oxygen free radicals, so that the surface of the indium tin oxide film can be roughened by controlling the ratio of hydrogen free radicals to oxygen free radicals, and thus the degree of reduction of indium ions and tin ions by hydrogen free radicals and the degree of oxidation and reduction of indium and tin by oxygen free radicals can be controlled to control the degree of surface roughening of the indium tin oxide film, thereby avoiding the situation that the surface roughening of the indium tin oxide film is incomplete or excessive roughening damage and failure after the surface roughening of the indium tin oxide film is avoided, so that the surface of the indium tin oxide film can be fully roughened. The roughening of the surface of the indium tin oxide film will not cause damage and failure, and the degree of the roughening of the surface of the indium tin oxide film can be controlled from two aspects: the ratio of hydrogen free radicals and oxygen free radicals and the duration of the roughening stage, thereby improving the controllability of the roughening degree of the surface of the indium tin oxide film. In addition, since the hydrogen free radicals and oxygen free radicals will not cause chemical corrosion damage to metal film layers such as silicon oxide, aluminum, titanium, etc., and since the energy generated by dissociating water vapor to generate hydrogen free radicals and dissociating oxygen to generate oxygen free radicals is relatively small, no physical bombardment damage will be caused to the indium tin oxide film and the lower film layer of the indium tin oxide film. Therefore, the surface roughening method of the indium tin oxide film provided by the present invention can be used for the indium tin oxide film with the lower film layer exposed by patterning, and the indium tin oxide film with the lower film layer being a metal film layer such as silicon oxide, aluminum, titanium, etc., thereby improving the applicability of the surface roughening of the indium tin oxide film. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 A flow chart of a method for roughening the surface of an indium tin oxide film provided in an embodiment of the present invention;
[0028] Figure 2 Another flow chart of the method for roughening the surface of an indium tin oxide film provided in an embodiment of the present invention;
[0029] Figure 3 A schematic structural diagram of a wafer prepared with a front film layer provided in an embodiment of the present invention;
[0030] Figure 4 A schematic diagram of a structure in which an indium tin oxide thin film is prepared on a wafer prepared with a front film layer and provided in an embodiment of the present invention;
[0031] Figure 5 A schematic diagram of a structure in which a photoresist is applied to a wafer prepared with an indium tin oxide thin film according to an embodiment of the present invention;
[0032] Figure 6A schematic structural diagram of a patterned wafer coated with photoresist provided in an embodiment of the present invention;
[0033] Figure 7 A schematic diagram of a structure in which an indium tin oxide film corresponding to a photoresist opening on a wafer is completely etched according to an embodiment of the present invention;
[0034] Figure 8 A schematic structural diagram of a wafer with a patterned indium tin oxide thin film with photoresist removed provided by an embodiment of the present invention;
[0035] Fig. 9 A schematic structural diagram of a wafer with a roughened indium tin oxide film surface provided by an embodiment of the present invention;
[0036] Fig.10 Schematic diagram of the indium tin oxide film before roughening;
[0037] Fig.11 A schematic diagram of an indium tin oxide film roughened by the indium tin oxide film surface roughening method provided in an embodiment of the present invention;
[0038] Fig.12 Schematic diagram of an over-roughened indium tin oxide film;
[0039] Description of reference numerals:
[0040] 1-wafer; 2-indium tin oxide film; 3-photoresist. DETAILED DESCRIPTION
[0041] In order to enable those skilled in the art to better understand the technical solution of the present invention, the surface roughening method of an indium tin oxide film provided by the present invention is described in detail below with reference to the accompanying drawings.
[0042] like Figure 1 , Figure 8 and Fig. 9 As shown, this embodiment provides a method for roughening the surface of an indium tin oxide film, comprising:
[0043] S1, a preparation stage, placing a wafer 1 prepared with an indium tin oxide thin film 2 in a process chamber using a microwave plasma source, introducing oxygen and water vapor, and forming an atmosphere of a mixture of oxygen and water vapor in the process chamber under a first process condition;
[0044] S2, a roughening stage, wherein oxygen and water vapor are introduced, and under the second process conditions, the water vapor is dissociated to generate hydrogen free radicals, and the oxygen is dissociated to generate oxygen free radicals. The hydrogen free radicals are used to reduce the indium ions and tin ions in the indium tin oxide, and the oxygen free radicals are used to oxidize the reduced indium and tin. By controlling the ratio of hydrogen free radicals to oxygen free radicals, the surface of the indium tin oxide film 2 is roughened.
[0045] The surface roughening method of an indium tin oxide film provided by an embodiment of the present invention comprises placing a wafer 1 prepared with an indium tin oxide film 2 in a process chamber in a preparation stage, and forming an atmosphere mixed with oxygen and water vapor in the process chamber, so that in the roughening stage, water vapor is dissociated to generate hydrogen free radicals, and oxygen is dissociated to generate oxygen free radicals, indium ions and tin ions in the indium tin oxide are reduced by means of hydrogen free radicals, and the reduced indium and tin are oxidized by means of oxygen free radicals, so that the surface of the indium tin oxide film 2 can be roughened by controlling the ratio of hydrogen free radicals and oxygen free radicals, and the degree of reduction of indium ions and tin ions by hydrogen free radicals and the degree of oxidation and reduction of indium and tin by oxygen free radicals can be controlled to control the degree of roughening of the surface of the indium tin oxide film 2, so as to avoid the situation that the surface of the indium tin oxide film 2 is not completely roughened or is damaged and failed due to excessive roughening after roughening, so that the surface of the indium tin oxide film 2 can be fully roughened. The roughening will not cause damage and failure, and then the degree of surface roughening of the indium tin oxide film 2 can be controlled from two aspects: the ratio of hydrogen radicals and oxygen radicals and the duration of the roughening stage, thereby improving the controllability of the surface roughening degree of the indium tin oxide film 2. In addition, since hydrogen radicals and oxygen radicals will not cause chemical corrosion damage to metal film layers such as silicon oxide, aluminum, titanium, etc., and since the energy generated by dissociating water vapor to generate hydrogen radicals and dissociating oxygen to generate oxygen radicals is relatively small, physical bombardment damage will not be caused to the indium tin oxide film 2 and the lower film layer of the indium tin oxide film 2. Therefore, the surface roughening method of the indium tin oxide film provided in the embodiment of the present invention can be used for the indium tin oxide film 2 whose lower film layer is patterned and exposed, and the indium tin oxide film 2 whose lower film layer is a metal film layer such as silicon oxide, aluminum, titanium, etc., thereby improving the applicability of the surface roughening of the indium tin oxide film 2.
[0046] Indium tin oxide is a mixture that can be made of 90% indium oxide (In2O3) and 10% tin oxide (SnO2). In the roughening stage, when the water vapor in the process chamber dissociates to generate hydrogen radicals, the hydrogen radicals will contact the wafer 1 prepared with the indium tin oxide film 2 placed in the process chamber. Since the hydrogen radicals have strong reducing properties, when the hydrogen radicals contact the indium tin oxide film 2, the hydrogen radicals can convert the indium ions (In2O3) in the indium tin oxide into indium ions. 3+ ) is reduced to indium (In), and can convert the tin ions (Sn 4+) is reduced to tin (Sn), thereby destroying the crystal structure of the indium tin oxide film 2 and roughening the surface of the indium tin oxide film 2. During the reduction process, hydrogen can combine with oxygen in the indium tin oxide to generate water. The water can form water vapor in the high-temperature process chamber environment and be pumped out by the vacuum pump. In the process of dissociating water vapor, the oxygen in the process chamber will also be dissociated to generate oxygen free radicals. The oxygen free radicals can oxidize the reduced indium and tin. By controlling the ratio of hydrogen free radicals and oxygen free radicals, part of the reduced indium and tin can be oxidized by oxygen free radicals, while the other part of the indium and tin is still in a reduced state, so that the indium tin oxide film 2 is in a state of surface roughening. In this way, by controlling the ratio of hydrogen free radicals and oxygen free radicals, the degree of reduction of indium ions and tin ions by hydrogen free radicals and the degree of oxidation of reduced indium and tin by oxygen free radicals can be controlled. When the ratio of hydrogen free radicals and oxygen free radicals is large, the indium tin film 2 is in a state of surface roughening. When there are more indium and tin in the reduced state, the surface roughening degree of the indium tin oxide film 2 is greater. When the ratio of hydrogen radicals to oxygen radicals is smaller, there are less indium and tin in the reduced state, and the surface roughening degree of the indium tin oxide film 2 is smaller. Thus, the surface roughening degree of the indium tin oxide film 2 is controlled to avoid the situation that the surface roughening of the indium tin oxide film 2 is not completely roughened or excessively roughened, resulting in damage and failure. Therefore, the surface of the indium tin oxide film 2 can be sufficiently roughened without causing damage and failure. Furthermore, when the indium tin oxide film 2 is applied to a light-emitting diode (LED) device, the situation that the brightness of the light-emitting diode is not significantly improved or the brightness is reduced is avoided.
[0047] like Fig.10 As shown, it is a schematic diagram of the indium tin oxide film 2 before roughening. Fig.11 FIG. 2 is a schematic diagram of an indium tin oxide film 2 roughened by the indium tin oxide film surface roughening method provided by an embodiment of the present invention. Fig.12 As shown, it is a schematic diagram of an over-roughened indium tin oxide film 2. It can be seen that the roughness of the indium tin oxide film 2 after being roughened by the indium tin oxide film surface roughening method provided by the embodiment of the present invention is between the roughness of the indium tin oxide film 2 before roughening and the roughness of the over-roughened indium tin oxide film 2. That is, the indium tin oxide film 2 after being roughened by the indium tin oxide film surface roughening method provided by the embodiment of the present invention can control the degree of surface roughening of the indium tin oxide film 2 by controlling the ratio of hydrogen radicals and oxygen radicals, thereby avoiding the situation that the surface of the indium tin oxide film 2 is not completely roughened or is damaged and failed due to excessive roughening after roughening, so that the surface of the indium tin oxide film 2 can be sufficiently roughened without causing damage and failure.
[0048] In the roughening stage, a certain power can be applied to the microwave plasma source to generate hydrogen free radicals and oxygen free radicals. By using the microwave plasma source to dissociate water vapor to generate hydrogen free radicals and oxygen to generate oxygen free radicals, the speed of water vapor dissociating to generate hydrogen free radicals and oxygen dissociating to generate oxygen free radicals can be increased, and the process efficiency can be improved. In addition, since the energy of the microwave plasma source to dissociate water vapor to generate hydrogen free radicals and oxygen to generate oxygen free radicals is relatively small, the energy of hydrogen free radicals and oxygen free radicals bombarding the indium tin oxide film 2 is relatively small, and physical bombardment damage will not be caused to the indium tin oxide film 2 and the lower film layer of the indium tin oxide film 2.
[0049] For example, an inductively coupled plasma source (ICP) is used to dissociate water vapor to generate hydrogen free radicals, and to dissociate oxygen to generate oxygen free radicals. Since the inductively coupled plasma source needs to set a lower electrode on the supporting component that supports the wafer 1, and needs to apply a certain power to the lower electrode, the hydrogen free radicals and the oxygen free radicals will bombard the indium tin oxide film 2 under the attraction of the lower electrode, and the bombardment energy is relatively large, which may cause physical bombardment damage to the indium tin oxide film 2 and the lower film layer of the indium tin oxide film 2. However, the microwave plasma source does not need to set a lower electrode on the supporting component that supports the wafer 1. Therefore, the hydrogen free radicals and the oxygen free radicals will not be attracted to bombard the indium tin oxide film 2, which makes the hydrogen free radicals generated by the microwave plasma source dissociating water vapor and the oxygen free radicals generated by the microwave plasma source dissociating oxygen have less energy to bombard the indium tin oxide film 2, and will not cause physical bombardment damage to the indium tin oxide film 2 and the lower film layer of the indium tin oxide film 2.
[0050] In a preferred embodiment of the present invention, controlling the ratio of hydrogen radicals to oxygen radicals may include: controlling the ratio of oxygen to water vapor to control the ratio of hydrogen radicals to oxygen radicals, and the ratio of oxygen to water vapor may be 5:1-8:1. That is, the ratio of oxygen to water vapor is 5:1-8:1, which can further avoid the situation that the surface of the indium tin oxide film 2 is not completely roughened or excessively roughened and damaged and failed after roughening, so as to further make the surface of the indium tin oxide film 2 fully roughened without causing damage and failure.
[0051] In a preferred embodiment of the present invention, the second process condition may include: the flow rate of oxygen is 600sccm-1000sccm, and the flow rate of water vapor is 100sccm-150sccm. This can further avoid the situation that the surface of the indium tin oxide thin film 2 is not completely roughened or excessively roughened and damaged and failed after roughening, so as to further ensure that the surface of the indium tin oxide thin film 2 can be fully roughened without causing damage and failure.
[0052] In a preferred embodiment of the present invention, the second process condition may further include: the frequency of the microwave plasma source is 2.45 GHz, the power of the microwave plasma source is 900 W-1300 W; the vacuum degree in the process chamber is 900 mTorr-1200 mTorr; the duration is 15 s-40 s. This can further avoid the situation that the surface of the indium tin oxide film 2 is not completely roughened or excessively roughened and damaged and failed after roughening, so as to further make the surface of the indium tin oxide film 2 fully roughened without causing damage and failure.
[0053] like Figure 2 and Fig. 9 As shown, in a preferred embodiment of the present invention, after the roughening stage, the method for roughening the surface of an indium tin oxide film may further include:
[0054] S3, oxidation stage, introducing oxygen into the process chamber under the third process condition to dissociate the oxygen into oxygen free radicals, which are used to combine with oxygen vacancies in the roughened indium tin oxide film 2.
[0055] This is because after the surface of the indium tin oxide film 2 is roughened, the oxygen vacancy concentration on the surface of the indium tin oxide film 2 may be greatly different from the oxygen vacancy concentration in the bulk of the indium tin oxide film 2 below the surface of the indium tin oxide film 2, which may affect the semiconductor properties of the indium tin oxide film 2. By introducing oxygen into the process chamber and dissociating the oxygen to generate oxygen free radicals, the oxygen free radicals can be combined with the oxygen vacancies on the surface of the roughened indium tin oxide film 2 to make the oxygen vacancy concentration on the surface of the indium tin oxide film 2 close to the oxygen vacancy concentration in the bulk of the indium tin oxide film 2 below the surface of the indium tin oxide film 2, thereby improving the semiconductor properties of the roughened indium tin oxide film 2.
[0056] In the oxidation stage, a certain power can be applied to the microwave plasma source to generate oxygen dissociation to generate oxygen free radicals. By using the microwave plasma source to dissociate oxygen to generate oxygen free radicals, the speed of oxygen dissociation to generate oxygen free radicals can be increased, and the process efficiency can be improved. In addition, since the energy of the microwave plasma source to dissociate oxygen to generate oxygen free radicals is relatively small, the energy of the oxygen free radicals bombarding the indium tin oxide film 2 is relatively small, and physical bombardment damage will not be caused to the indium tin oxide film 2 and the lower film layer of the indium tin oxide film 2.
[0057] For example, an inductively coupled plasma source is used to dissociate oxygen to generate oxygen free radicals. Since the inductively coupled plasma source needs to set a lower electrode on the supporting component that supports the wafer 1, and needs to apply a certain power to the lower electrode, the oxygen free radicals will bombard the indium tin oxide film 2 under the attraction of the lower electrode. The bombardment energy is relatively large, which may cause physical bombardment damage to the indium tin oxide film 2 and the lower film layer of the indium tin oxide film 2. However, the microwave plasma source does not need to set a lower electrode on the supporting component that supports the wafer 1. Therefore, the oxygen free radicals will not be attracted to bombard the indium tin oxide film 2. This makes the energy of the oxygen free radicals generated by the microwave plasma source dissociating oxygen to bombard the indium tin oxide film 2 and the lower film layer of the indium tin oxide film 2 relatively small, and will not cause physical bombardment damage to the indium tin oxide film 2 and the lower film layer of the indium tin oxide film 2.
[0058] In a preferred embodiment of the present invention, the third process condition may include: the flow rate of oxygen is 600 sccm-1000 sccm, which can improve the effect of oxygen free radicals combining with oxygen vacancies on the surface of the roughened indium tin oxide film 2, thereby further improving the semiconductor properties of the roughened indium tin oxide film 2.
[0059] In a preferred embodiment of the present invention, the third process condition may further include: the frequency of the microwave plasma source is 2.45 GHz, the power of the microwave plasma source is 900 W-1300 W; the vacuum degree in the process chamber is 900 mTorr-1200 mTorr; the duration is 10 s-20 s. This can improve the effect of oxygen free radicals combining with oxygen vacancies on the surface of the roughened indium tin oxide film 2, thereby further improving the semiconductor properties of the roughened indium tin oxide film 2.
[0060] In a preferred embodiment of the present invention, in the preparation stage, the wafer 1 prepared with the indium tin oxide thin film 2 can be placed on a heating component in the process chamber, and the temperature of the wafer 1 can be heated to greater than or equal to 100° C. by the heating component.
[0061] This can increase the reaction rate in the roughening stage, thereby improving process efficiency, and can prevent water vapor from condensing into liquid water, thereby improving process stability.
[0062] In a preferred embodiment of the present invention, the first process conditions may include: the temperature of the heating component is 220°C-250°C; the power of the microwave plasma source is 0W; the vacuum degree in the process chamber is 900mTorr-1200mTorr; the flow rate of oxygen is 600sccm-1000sccm; the flow rate of water vapor is 100sccm-150sccm; the duration is 15s-40s. This can further increase the reaction rate in the roughening stage, thereby further improving the process efficiency, and can further avoid the condensation of water vapor to form liquid water, thereby further improving the process stability.
[0063] Optionally, the first process condition may be: the vacuum degree in the process chamber is 1000 mTorr, the power of the microwave plasma source is 0 W, the flow rate of oxygen is 700 sccm, the flow rate of water vapor is 150 sccm, the temperature of the heating component is 250° C., and the duration is 30 s.
[0064] Optionally, the second process condition may be: the vacuum degree in the process chamber is 1000 mTorr, the power of the microwave plasma source is 1000 W, the flow rate of oxygen is 700 sccm, the flow rate of water vapor is 150 sccm, the temperature of the heating component is 250° C., and the duration is 30 s.
[0065] Optionally, the third process condition may be: the vacuum degree in the process chamber is 1000 mTorr, the power of the microwave plasma source is 1000 W, the flow rate of oxygen is 700 sccm, the flow rate of water vapor is 0 sccm, the temperature of the heating component is 250° C., and the duration is 10 s.
[0066] like Figure 3-Figure 9 As shown, in a preferred embodiment of the present invention, before the preparation stage, the method for roughening the surface of an indium tin oxide film may further include:
[0067] In the film-making stage, a front film layer is prepared on the wafer 1, and the wafer 1 on which the front film layer is prepared is cleaned;
[0068] Preparing an indium tin oxide thin film 2 on a wafer 1 having a front film layer prepared thereon;
[0069] Applying a photoresist 3 on a wafer 1 on which an indium tin oxide thin film 2 is prepared;
[0070] Covering the wafer 1 coated with the photoresist 3 with a desired mask plate, and exposing and developing the wafer 1 coated with the photoresist 3 to form a desired pattern;
[0071] Etching the wafer 1 formed with the desired pattern, and completely etching the indium tin oxide film 2 on the wafer 1 corresponding to the opening of the photoresist 3;
[0072] The photoresist 3 is removed to form an indium tin oxide thin film 2 having a desired pattern on the wafer 1 .
[0073] In this way, a patterned indium tin oxide thin film 2 can be prepared on the wafer 1 .
[0074] like Figure 3 As shown, a front film layer is prepared on a wafer 1, and the wafer 1 prepared with the front film layer is cleaned. Optionally, the front film layer can be prepared on the wafer 1 by deposition, and the front film layer can have a good lattice match with the indium tin oxide film 2, and the front film layer can be a film with stable physical and chemical properties in oxygen plasma, for example, a silicon oxide or titanium film.
[0075] like Figure 4 As shown, when preparing an indium tin oxide film 2 on a wafer 1 having a front film layer, optionally, the indium tin oxide film 2 can be prepared on the wafer 1 having the front film layer by deposition. Optionally, the indium tin oxide film 2 can be prepared on the wafer 1 having the front film layer by high-temperature sputtering deposition. Optionally, the thickness of the indium tin oxide film 2 can be
[0076] like Figure 5 As shown, when applying photoresist 3 on wafer 1 prepared with indium tin oxide film 2, optionally, photoresist 3 may be applied on wafer 1 prepared with indium tin oxide film 2 by spin coating. Optionally, the thickness of photoresist 3 may be 1 μm.
[0077] like Figure 6 As shown, a required mask plate (not shown in the figure) is covered on the wafer 1 coated with the photoresist 3, and the wafer 1 coated with the photoresist 3 is exposed and developed to form a required pattern, so that the photoresist 3 is patterned.
[0078] like Figure 7 As shown, the wafer 1 formed with the desired pattern is etched to completely etch the indium tin oxide film 2 on the wafer 1 corresponding to the opening of the photoresist 3 , that is, the indium tin oxide film 2 is patterned corresponding to the patterning of the photoresist 3 .
[0079] like Figure 8 As shown, the photoresist 3 is removed to form an indium tin oxide film 2 having a desired pattern on the wafer 1, that is, the photoresist 3 above the patterned indium tin oxide film 2 is removed to completely expose the patterned indium tin oxide film 2, thereby forming an indium tin oxide film 2 having a desired pattern on the wafer 1. When the photoresist 3 is removed to form an indium tin oxide film 2 having a desired pattern on the wafer 1. Optionally, wet stripping (e.g., EKC solution or acetone ultrasound) or dry stripping (e.g., plasma stripping in a nitrogen or oxygen atmosphere) may be used.
[0080] like Fig. 9 As shown, after the film forming stage, a preparation stage and a roughening stage may be performed to roughen the surface of the indium tin oxide thin film 2 .
[0081] In summary, the method for roughening the surface of an indium tin oxide film provided in the embodiment of the present invention can improve the applicability of roughening the surface of an indium tin oxide film 2 and improve the controllability of the roughening degree.
[0082] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.
Claims
1. A method for roughening the surface of an indium tin oxide film, characterized in that: include: In the preparation stage, the wafer prepared with the indium tin oxide thin film is placed in a process chamber using a microwave plasma source, oxygen and water vapor are introduced, and an atmosphere mixed with the oxygen and the water vapor is formed in the process chamber under a first process condition; In the roughening stage, oxygen and water vapor are introduced, and the water vapor is dissociated to generate hydrogen free radicals under the second process condition, and the oxygen is dissociated to generate oxygen free radicals, the hydrogen free radicals are used to reduce the indium ions and tin ions in the indium tin oxide, and the oxygen free radicals are used to oxidize the reduced indium and tin, and the ratio of the hydrogen free radicals to the oxygen free radicals is controlled by controlling the ratio of the oxygen to the water vapor to be 5:1-8:1, so as to roughen the surface of the indium tin oxide film; In the oxidation stage, oxygen is introduced into the process chamber under the third process condition to dissociate the oxygen into oxygen free radicals, and the oxygen free radicals are used to combine with oxygen vacancies on the surface of the roughened indium tin oxide film.
2. The method for roughening the surface of an indium tin oxide film according to claim 1, characterized in that: The second process conditions include: the flow rate of the oxygen gas is 600 sccm-1000 sccm, and the flow rate of the water vapor is 100 sccm-150 sccm.
3. The method for roughening the surface of an indium tin oxide film according to claim 2, characterized in that: The second process condition also includes: The frequency of the microwave plasma source is 2.45 GHz, the power of the microwave plasma source is 900 W-1300 W; the vacuum degree in the process chamber is 900 mTorr-1200 mTorr; and the duration is 15 s-40 s.
4. The method for roughening the surface of an indium tin oxide film according to claim 1, characterized in that: The third process condition includes: the flow rate of the oxygen gas is 600 sccm-1000 sccm.
5. The method for roughening the surface of an indium tin oxide film according to claim 4, characterized in that: The third process condition also includes: the frequency of the microwave plasma source is 2.45 GHz, the power of the microwave plasma source is 900 W-1300 W; the vacuum degree in the process chamber is 900 mTorr-1200 mTorr; and the duration is 10 s-20 s.
6. The method for roughening the surface of an indium tin oxide film according to claim 1, characterized in that: In the preparation stage, the wafer prepared with the indium tin oxide thin film is placed on a heating component in the process chamber, and the temperature of the wafer is heated to greater than or equal to 100° C. by the heating component.
7. The method for roughening the surface of an indium tin oxide film according to claim 6, characterized in that: The first process conditions include: the temperature of the heating component is 220°C-250°C; the power of the microwave plasma source is 0W; the vacuum degree in the process chamber is 900mTorr-1200mTorr; the flow rate of the oxygen is 600sccm-1000sccm, and the flow rate of the water vapor is 100sccm-150sccm; and the duration is 15s-40s.
8. The method for roughening the surface of an indium tin oxide film according to claim 1, characterized in that: Before the preparation stage, the method for roughening the surface of an indium tin oxide film further comprises: In the film-making stage, a front film layer is prepared on the wafer, and the wafer on which the front film layer is prepared is cleaned; Preparing the indium tin oxide thin film on the wafer prepared with the front film layer; Applying photoresist on the wafer prepared with the indium tin oxide thin film; Covering the wafer coated with the photoresist with a desired mask plate, and exposing and developing the wafer coated with the photoresist to form a desired pattern; Etching the wafer formed with the desired pattern to completely etch the indium tin oxide film on the wafer corresponding to the photoresist opening; The photoresist is removed to form the ITO film having the desired pattern on the wafer.