阅读说明：本技术 一种导电金属氧化物的加工方法 (Processing method of conductive metal oxide ) 是由 黄志刚 于 2018-06-05 设计创作，主要内容包括：本发明提供一种导电金属氧化物的加工方法,在刻蚀完的晶片后,先采用加热方式去除晶片光刻胶图形、导电金属氧化物层及金属层表面残留的卤族元素以及卤族元素化合物,可有效避免卤族元素对金属层的腐蚀,然后采用氧气(O<Sub>2</Sub>)的等离子体去除光刻胶,且气体中不包含水气(H<Sub>2</Sub>O),可有效避免水气的等离子体对导电金属氧化物的腐蚀。采用本发明的加工方法,在完全去除光刻胶图形的同时,可以获得形貌完整的导电金属氧化物层-金属层的叠层结构。(The invention provides a processing method of conductive metal oxide, which is characterized in that after a wafer is etched, a heating mode is firstly adopted to remove a wafer photoresist pattern, a conductive metal oxide layer and residual halogen elements and halogen element compounds on the surface of a metal layer, so that the metal layer can be effectively prevented from being corroded by the halogen elements, and then oxygen (O) is adopted 2 ) The photoresist is removed by plasma, and the gas does not contain moisture (H) 2 O), the corrosion of the plasma of the water vapor to the conductive metal oxide can be effectively avoided. By adopting the processing method, the photoresist pattern is completely removed, and simultaneously, the laminated structure of the conductive metal oxide layer-metal layer with complete appearance can be obtained.)

1. A method of processing a conductive metal oxide, comprising the steps of:

1) Forming a metal layer on a substrate, wherein the metal layer is easy to react with halogen elements to cause corrosion;

2) Forming a conductive metal oxide layer on the metal layer;

3) Forming a photoresist pattern on the conductive metal oxide layer;

4) Etching the conductive metal oxide layer and the metal layer by using a gas containing a halogen element based on the photoresist pattern;

5) Removing halogen elements and halogen element compounds on the photoresist pattern, the conductive metal oxide layer and the surface of the metal layer in a heating mode; and

6) And removing the photoresist pattern.

2. The method of processing a conductive metal oxide according to claim 1, characterized in that: the halogen element includes at least one of fluorine element, chlorine element and bromine element.

3. The method for processing a conductive metal oxide according to claim 2, characterized in that: the etching gas in the step 4) comprises chlorine, boron trichloride, trifluoromethane, nitrogen and argon.

4. The method of processing a conductive metal oxide according to claim 1, characterized in that: the heating method is heating under a reduced pressure.

5. The method of processing a conductive metal oxide according to claim 1, characterized in that: the heating temperature of the heating mode is more than 100 ℃, and the heating time is more than 30 seconds.

6. The method for processing a conductive metal oxide according to claim 5, wherein: the heating temperature of the heating mode is more than 200 ℃, and the heating time is more than 60 seconds.

7. The method of processing a conductive metal oxide as claimed in claim 1, wherein in step 6), the photoresist pattern is removed by ashing.

8. The method for processing a conductive metal oxide according to claim 7, wherein: the ashing photoresist removing mode adopts oxygen plasma, and the gas source for ashing photoresist removing does not contain water vapor, so that the conductive metal oxide layer is prevented from being corroded by the water vapor plasma.

9. The method of processing a conductive metal oxide according to claim 1, characterized in that: the conductive metal oxide layer comprises an indium tin oxide layer and the metal layer comprises an aluminum layer.

10. The method of processing a conductive metal oxide according to claim 9, characterized in that: the base comprises a silicon substrate and a silicon dioxide layer positioned on the surface of the silicon substrate, and a titanium nitride layer is arranged between the aluminum layer and the silicon dioxide layer so as to improve the adhesive force of the aluminum layer and the silicon dioxide layer.

Technical Field

The invention belongs to the field of semiconductor manufacturing, and particularly relates to a processing method of a conductive metal oxide.

Background

Indium Tin Oxide (ITO) is used as a nano indium tin metal oxide, has excellent conductivity and transparency, and can cut off electron radiation, ultraviolet rays and far infrared rays harmful to the human body. Therefore, Indium Tin Oxide (ITO) is generally sprayed on glass, plastic, metal, and electronic display screens as a transparent conductive film while reducing electron radiation, ultraviolet radiation, and infrared radiation harmful to the human body.

When an OLED substrate is manufactured, Indium Tin Oxide (ITO) and metal Al are usually needed to be matched, and in order to form patterned Indium Tin Oxide (ITO) and metal Al, a mask is needed to define a photolithography pattern on the Indium Tin Oxide (ITO) and the metal Al, and then the Indium Tin Oxide (ITO) and the metal Al are dry-etched. The method comprises the following specific steps: al and Indium Tin Oxide (ITO) were sequentially deposited on a silicon oxide substrate. A patterned photoresist is formed on the surface of Indium Tin Oxide (ITO). And transferring the pattern defined by photoetching to lower-layer metal Al and Indium Tin Oxide (ITO) by adopting a dry etching process.

After etching of Indium Tin Oxide (ITO) and Al, if conventional H is used₂o and O₂Method for removing photoresist by plasma H₂The O plasma causes corrosion of the Indium Tin Oxide (ITO) film, resulting in abnormal pattern definition. But if O is used₂When the photoresist is removed by the plasma, the residual Cl will cause Al corrosion.

Based on the above, the invention provides a photoresist removing method after etching of Indium Tin Oxide (ITO) and metal Al, so that photoresist removal of Indium Tin Oxide (ITO) and metal Al can be smoothly completed after patterned etching, and both Indium Tin Oxide (ITO) and metal Al are ensured not to be corroded.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, the present invention provides a method for processing a conductive metal oxide, which solves the following problems: after etching of Indium Tin Oxide (ITO) and Al, if conventional H is used₂O and O₂Method for removing photoresist by plasma H₂The O plasma causes corrosion of the Indium Tin Oxide (ITO) film, resulting in abnormal pattern definition. But if O is used₂When the photoresist is removed by the plasma, the residual Cl will cause Al corrosion.

To achieve the above and other related objects, the present invention provides a method for processing a conductive metal oxide, comprising the steps of: 1) forming a metal layer on a substrate, wherein the metal layer is easy to react with halogen elements to cause corrosion; 2) forming a conductive metal oxide layer on the metal layer; 3) forming a photoresist pattern on the conductive metal oxide layer; 4) etching the conductive metal oxide layer and the metal layer by using a gas containing a halogen element based on the photoresist pattern; 5) removing halogen elements and halogen element compounds on the photoresist pattern, the conductive metal oxide layer and the surface of the metal layer in a heating mode; and 6) removing the photoresist pattern.

Preferably, the halogen element includes at least one of fluorine, chlorine and bromine.

Further, the etching gas in the step 4) comprises chlorine, boron trichloride, trifluoromethane, nitrogen and argon.

Preferably, the heating means is heating in a reduced pressure state.

Preferably, the heating temperature of the heating mode is more than 100 ℃, and the heating time is more than 30 seconds.

Preferably, the heating temperature of the heating mode is more than 200 ℃, and the heating time is more than 60 seconds.

preferably, in step 6), the photoresist pattern is removed by ashing.

Preferably, the ashing stripping manner adopts oxygen plasma, and a gas source of the ashing stripping manner does not contain moisture, so as to avoid the corrosion of the moisture plasma on the conductive metal oxide layer.

Preferably, the conductive metal oxide layer comprises an indium tin oxide layer and the metal layer comprises an aluminum layer.

preferably, the base comprises a silicon substrate and a silicon dioxide layer located on the surface of the silicon substrate, and a titanium nitride layer is further included between the aluminum layer and the silicon dioxide layer to improve the adhesion of the aluminum layer and the silicon dioxide layer.

As described above, the method for processing a conductive metal oxide of the present invention has the following advantageous effects:

After the wafer is etched, the wafer photoresist pattern, the conductive metal oxide layer and halogen elements and halogen element compounds on the surface of the metal layer are removed in a heating mode, and the residual halogen elements and halogen element compounds are removed at high temperature, so that the metal layer can be effectively prevented from being corroded by the halogen elements.

the invention adopts oxygen (O)₂) The plasma of (1) removing the photoresist, the gas containing no moisture (H)₂O), the corrosion of the plasma of the water vapor to the conductive metal oxide can be effectively avoided.

By adopting the processing method, the photoresist pattern is completely removed, and simultaneously, the laminated structure of the conductive metal oxide layer-metal layer with complete appearance can be obtained.

Drawings

FIG. 1 shows the use of conventional H₂O and O₂Scanning Electron microscopy of the plasma Photoresist stripping method H₂The O plasma causes corrosion of the Indium Tin Oxide (ITO) film, resulting in abnormal pattern definition.

Shown in FIG. 2 as using O₂The plasma removes the photoresist in a scanning electron micrograph, and the Cl residue can cause Al corrosion.

FIG. 3 is a flow chart illustrating the steps of the method of processing conductive metal oxides of the present invention.

fig. 4 to 8 are schematic structural views showing steps of the method for processing a conductive metal oxide according to the present invention.

FIG. 9 shows a scanning electron microscope image of a photoresist removed by the processing method of the present invention, in which the Indium Tin Oxide (ITO) and Al layers have complete shapes and no photoresist remains.

Description of the element reference numerals

101 substrate

102 titanium nitride layer

103 metal layer

104 conductive metal oxide layer

105 photo resist pattern

106 halogen element and compound of halogen element

S11-S16 steps 1) -6)

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.

Please refer to fig. 1 to 9. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the present invention, and the drawings only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation, and the type, quantity and proportion of each component in actual implementation may be changed arbitrarily, and the layout of the components may be more complicated.

as shown in fig. 3 to 9, the present embodiment provides a method for processing a conductive metal oxide, including the steps of:

As shown in fig. 3 and 4, step 1) S11 is performed first to form a metal layer 103 on the substrate 101, where the metal layer 103 is susceptible to corrosion caused by reaction with halogen elements.

For example, the base 101 may include a silicon substrate and a silicon dioxide layer (SiO) on the surface of the silicon substrate₂) The metal layer 103 includes an aluminum layer (Al). A titanium nitride layer (TiN)102 is further included between the aluminum layer and the silicon dioxide layer to improve adhesion of the aluminum layer (Al) and the silicon dioxide layer.

The titanium nitride layer (TiN)102 and the aluminum layer (Al) may be formed by vacuum evaporation, ion beam assisted deposition, and dc magnetron sputtering, for example. In this embodiment, the aluminum layer is deposited on the surface of the substrate 101 by a dc magnetron sputtering method, wherein an aluminum target is used as a target material, and Ar is used as a sputtering gas. In the direct current magnetron sputtering method, the flow range of Ar gas is 150 sccm-200 sccm, the power range of a direct current power supply is 2000W-3000W, and the sputtering temperature range is 100-150 ℃. The thickness of the aluminum thin film ranges from 100nm to 200nm, and specifically, in this embodiment, the thickness of the aluminum thin film may be 130 nm.

As shown in fig. 3 and 4, step 2) S12 is performed to form a conductive metal oxide layer 104 on the metal layer 103.

As an example, the conductive metal oxide layer 104 includes an indium tin oxide layer (ITO transparent conductive layer). And depositing an ITO transparent conducting layer on the surface of the aluminum layer by adopting a direct current magnetron sputtering method, wherein the temperature range adopted by the direct current magnetron sputtering method is between 200 and 300 ℃ so as to improve the light transmittance of the ITO transparent conducting layer, and the power range adopted by the direct current magnetron sputtering method is between 3000 and 3500W so as to improve the adhesion strength of the ITO transparent conducting layer and the aluminum layer.

The direct current magnetron sputtering method adopts an In-Sn-O target as a target material and Ar gas as sputtering gas, wherein In atoms and Sn atoms In the In-Sn-O target are sputtered into an ITO reaction cavity by ionized Ar ions, and the In atoms and the Sn atoms react with O ions In an excited state at the temperature of 200-300 ℃ to generate the ITO transparent conducting layer. The In-Sn-O target is used as a target material, so that the controllability of the components In the ITO transparent conductive layer can be effectively improved. In the In-Sn-O target, the mass ratio of In atoms is 85-90%, and the mass ratio of Sn atoms is 10-15%, so that the conductivity of the ITO transparent conductive layer is improved.

As an example, the thickness of the ITO transparent conductive layer ranges from 10nm to 120 nm. Preferably, the thickness of the ITO transparent conductive layer ranges from 80nm to 120nm, and in this embodiment, the thickness of the ITO transparent conductive layer may be 100 nm.

As shown in fig. 3 and 5, step 3) S13 is performed to form a photoresist pattern 105 on the conductive metal oxide layer 104.

For example, a spin coating process may be used to form a photoresist on the conductive metal oxide layer 104, and then a photolithography process may be used to form the photoresist pattern 105.

As shown in fig. 3 and 6, step 4) S14 is performed, and the conductive metal oxide layer 104 and the metal layer 103 are etched using a gas containing a halogen element based on the photoresist pattern 105.

The halogen element includes at least one of fluorine element, chlorine element and bromine element. Preferably, the etching gas of the embodiment may include chlorine, boron trichloride, trifluoromethane, nitrogen and argon, so as to improve the etching efficiency and optimize the etching morphology.

After the etching is completed, halogen elements and halogen element compounds 106 may remain on the surfaces of the photoresist pattern 105, the conductive metal oxide layer 104 and the metal layer 103, as shown in fig. 6.

As shown in fig. 3 and 7, step 5) S15 is performed to remove the halogen element and the halogen element compound 106 on the surfaces of the photoresist pattern 105, the conductive metal oxide layer 104, and the metal layer 103 by heating.

preferably, the heating method is heating under reduced pressure to increase the removal rate and the effective removal amount of the halogen element and the halogen element compound 106, so that the halogen element and the halogen element compound 106 are substantially not left.

As an example, the heating temperature of the heating mode is more than 100 ℃, and the heating time is more than 30 seconds. Preferably, the heating temperature of the heating mode is more than 200 ℃ and the heating time is more than 60 seconds, so as to further ensure that the halogen element and the halogen element compound 106 are completely removed.

As shown in fig. 3 and 8, step 6) is finally performed to remove the photoresist pattern 105, and finally, the wafer is cleaned using a wet cleaning solution to remove polymers generated during the etching process.

The photoresist pattern 105 may be removed by ashing. The ashing photoresist removal mode adopts oxygen plasma, and the gas source for ashing photoresist removal does not contain water vapor, so as to avoid the corrosion of the water vapor plasma on the conductive metal oxide layer 104. The oxygen plasma may oxidize the photoresist reaction product gas to achieve the removal of the photoresist pattern 105.

FIG. 9 is a scanning electron microscope image of a photoresist removed by the processing method of the present invention, which shows that the processing method of the present invention can make the shapes of the Indium Tin Oxide (ITO) and Al layers complete and the photoresist has no residue.

As described above, the method for processing a conductive metal oxide of the present invention has the following advantageous effects:

after the wafer is etched, the wafer photoresist pattern, the conductive metal oxide layer and halogen elements and halogen element compounds on the surface of the metal layer are removed in a heating mode, and the residual halogen elements and halogen element compounds are removed at high temperature, so that the metal layer can be effectively prevented from being corroded by the halogen elements.

The invention adopts oxygen (O)₂) The plasma of (1) removing the photoresist, the gas containing no moisture (H)₂O), the corrosion of the plasma of the water vapor to the conductive metal oxide can be effectively avoided.

By adopting the processing method, the photoresist pattern is completely removed, and simultaneously, the laminated structure of the conductive metal oxide layer-metal layer with complete appearance can be obtained.

Therefore, the invention effectively overcomes various defects in the prior art and has high industrial utilization value.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.