TW202121531A - Atmospheric pressure plasma etching of glass surfaces to reduce electrostatic charging during processing - Google Patents

Abstract

A treated glass substrate for use in a flat panel display includes a first side configured to hold a plurality of thin-film transistors and a second side positioned on a side of the glass substrate opposite to the first side. The second side is treated using a dry etching process to change a surface composition of the second side. The surface composition of the second side includes a first Al/Si ratio to a first depth of about 1 nm in a range of about 38% to about 42% of a surface composition of an untreated glass substrate to the first depth, and a second Al/Si ratio to a second depth of about 10 nm in a range of about 71% to about 73% of the surface composition of the untreated glass substrate to the second depth.

Description

Reduce the etching of the electrostatically charged glass surface with atmospheric pressure paste during processing

This application claims priority rights in U.S. Provisional Application No. 62/880,261 filed on July 30, 2019 in accordance with the Patent Law, the content of which is incorporated herein by reference in its entirety.

The present invention relates to the use of an Atmospheric Paste Etching (APPE) process on the glass surface to reduce electrostatic charging, which occurs during the processing of the glass.

Flat or curved substrates made of optically transparent materials such as glass are commonly used in flat panel displays, photovoltaic devices, and other suitable applications. These displays and devices are made through a series of manufacturing steps in which glass materials are transported in various processing steps. The interaction between the glass and the processing equipment can cause electrical charges to be imparted or accumulated on one or more glass surfaces. It would be desirable to minimize the charge imparted or accumulated on the glass surface.

The present invention provides a treated glass substrate with surface roughness and surface composition, which reduces electrostatic charging on the glass surface.

In an example, a processed glass substrate used in a flat panel display may include a first side configured to hold a plurality of thin film transistors, and a second side positioned on the side of the glass substrate opposite to the first side . A dry etching process can be used to treat the second side to change the surface composition of the second side. The surface composition of the second side may include the first Al/Si ratio to the first depth of about 1 nm in the range of about 38% to about 42% of the surface composition of the untreated glass substrate to the first depth, and to about The second Al/Si ratio at the second depth of 10 nm is in the range of about 71% to about 73% of the surface composition of the untreated glass substrate to the second depth.

In one aspect, the glass substrate may include boroaluminosilicate glass.

In another aspect, the dry etching process may be an Atmospheric Electro-Plastic Etching (APPE) process.

In another aspect, the surface composition of the first side may be substantially similar to the surface composition of the untreated glass substrate.

In another aspect, the surface composition of the second side may include the first Mg/Si ratio to the first depth in the range of about 72% to about 81% of the surface composition of the untreated glass substrate to the first depth , And the surface composition of the second side may include the second Mg/Si ratio to the second depth in the range of about 72% to about 81% of the surface composition of the untreated glass substrate to the second depth.

In another aspect, the surface composition of the second side may include the first Ca/Si ratio to the first depth in the range of about 33% to about 34% of the surface composition of the untreated glass substrate to the first depth , And the surface composition of the second side may include the second Ca/Si ratio to the second depth in the range of about 77% to about 99% of the surface composition of the untreated glass substrate to the second depth.

In another aspect, the surface composition of the second side may include a concentration of fluorine to the first depth in a range of about 290% to about 330% of the concentration of fluorine of the surface composition of the untreated glass substrate to the first depth. in.

In another aspect, the average roughness Ra of the second side may be in the range of about 0.6 nm to about 1 nm.

In another aspect, after the test is lifted from the vacuum chuck, the average glass voltage of the glass substrate can be reduced by at least about 50% compared with the average glass voltage of the untreated glass substrate.

In another aspect, after the processed glass substrate is packaged adjacent to the interleaf paper, vibrated for at least 2 hours, and cleaned with a solution containing about 1% of the cleaning agent, it exhibits a higher performance than that of the unprocessed glass substrate. A reduction in the average glass voltage of at least 50% of the average glass voltage.

In another aspect, the haze of the processed glass substrate is not more than about 10% greater than the haze of the untreated glass substrate.

In an example of the method according to the present invention, a method of producing a processed glass substrate used in a flat panel display is provided. This method may include heating the glass substrate to a predetermined processing temperature and exposing the first side of the heated glass substrate to air, while exposing the second side of the heated glass substrate to HF plasma to etch the second side of the glass substrate and change The surface of the second side is composed to form a treated glass substrate. The surface composition of the second side of the processed glass substrate may include a first Al/Si ratio to a first depth of about 1 nm, which is about 38% to about 42% of the surface composition of the untreated glass substrate to the first depth. In the range, and the surface composition of the second side of the treated glass substrate may include a second Al/Si ratio to a second depth of about 10 nm, which is about 71% to about 71% of the surface composition of the untreated glass substrate to the second depth. About 73% of the range.

The present invention provides a method of producing a glass substrate that has improved electrostatic charging (ESC) performance compared to those substrates that do not use the method of the present invention. The glass substrate of the present invention may be provided for manufacturing flat panel display devices, such as liquid crystal displays (LCD), light emitting diode (LED) displays, or organic light emitting diode (OLED) displays. In certain embodiments, the glass substrate is optically transparent. Examples of substrates include, but are not limited to, flat or curved glass panels.

Unless specifically specified otherwise, the terms "glass substrate" or "glass" used herein are understood to encompass any object made wholly or partly of glass. The glass substrate includes a single substrate, or a laminated layer of glass and glass, a laminated layer of glass and non-glass materials, a laminated layer of glass and crystalline material, and a laminated layer of glass and glass-ceramic (including an amorphous phase and a crystalline phase).

Glass substrates such as glass panels may be flat or curved, and transparent or substantially transparent. As used herein, the term "transparent" means that an object with a thickness of about 1 mm has a penetration of greater than about 85% in the visible region (400-700 nm) of the spectrum. For example, an exemplary transparent glass panel may have a transmittance in the visible range of greater than about 85%, such as greater than about 90%, greater than about 95%, or greater than about 99%, including between these transmittances All ranges and sub-ranges of. According to various embodiments, the glass object may have a transmittance in the visible light region of less than about 50%, such as less than about 45%, less than about 40%, less than about 35%, less than about 30%, less than about 25%, or less than About 20%, including all ranges and sub-ranges between these penetration rates. In certain embodiments, the example glass panel may have a transmittance of greater than about 50% in the ultraviolet (UV) region (100-400 nm), such as greater than about 55%, greater than about 60%, greater than about 65%, A penetration rate greater than about 70%, greater than about 75%, greater than about 80%, greater than about 85%, greater than about 90%, greater than about 95%, or greater than about 99%, including all between these penetration rates Ranges and sub-ranges.

Example glasses may include, but are not limited to, aluminosilicate glass, alkali metal-aluminosilicate glass, borosilicate glass, alkali metal-borosilicate glass, aluminoborosilicate glass, alkali metal-aluminoborosilicate Salt glass, and other suitable glass. As non-limiting examples of suitable glass can be used a glass substrate teachings of the present invention include, for example, LOTUS ™ NXT from Corning ^{Incorporated, IRIS ™, GORILLA ®, ASTRA} ™ glass, and Eagle XG ^®. Although the various principles and teachings of the present invention can be used to combine other types of glass substrates, the glass substrates used are preferably alkaline earth boroaluminosilicate melt stretched glass, such as LOTUS™ NXT glass from Corning Incorporated.

The thin glass substrate that can be used in flat panel displays may have a functional A-side surface. Thin film transistors can be fabricated on the functional A side surface. On the side of the glass substrate opposite to the A side surface, the glass substrate may include a non-functional side or a B side. During various stages of manufacturing flat panel displays or other display devices, the B-side surface of the glass substrate may contact transportation equipment and/or handling equipment. Such transportation equipment and/or handling equipment can be made of various materials, including metals, ceramics, polymer materials, and the like. The interaction between these various dissimilar materials and the glass substrate can cause charging of the glass substrate, for example, through triboelectric effect or contact electrification. The electric charge transferred to the glass surface of the glass substrate is accumulated on the glass substrate. As electric charges are accumulated on the surface of the glass substrate, the surface voltage of the glass substrate also changes. This accumulation of charge on one or more surfaces of the glass substrate is called electrostatic charging (ESC).

The electrostatic charging of the B-side surface of the glass substrate may be undesirable because such electrostatic charging may degrade the performance of the glass substrate and/or damage the glass substrate. For example, electrostatic charging on the B side of the glass substrate can cause damage to the gate of the thin film transistor (TFT) device that can be deposited on the A side (or functional) surface of the glass substrate. Such gate damage can be caused by dielectric breakdown and/or electric field induced charging.

Electrostatic charging of the glass substrate can also be undesirable because such charging can attract particles such as dust, particulate debris, or other contaminants to the glass surface. This attraction and/or accumulation of dust and particulate debris can damage the glass surface or degrade the surface quality of the glass substrate.

In an exemplary embodiment of the present invention, the B-side surface of the glass substrate may be etched using one or more methods described below to increase the surface roughness of the B-side surface and improve one or more regions on the B-side surface Surface chemistry in China. Increased surface roughness and chemical changes in one or more surface layers on the B-side surface reduce the accumulation of electrostatic charge on the B-side surface. Furthermore, increasing the surface roughness and/or chemical changes will also reduce the friction between the glass substrate and the handling equipment and/or transportation equipment used during the processing of the glass substrate. The reduction of friction can reduce the wear of this equipment. This reduction in wear can increase the service life of handling equipment and/or transportation equipment and can reduce the necessary maintenance of such equipment. This can increase the processing operation time, increase the manufacturing yield, and reduce the cost of the overall flat panel display manufacturing process.

Referring now to FIGS. 1 and 2, an example glass substrate 20 is shown. Any suitable glass manufacturing process can be used to form this glass substrate. In one example, the glass substrate 20 is formed using a melt stretching process. The glass substrate 20 may include a first side (or A side) 22. The first side 22 may be the side of the glass substrate 20 on which thin film transistors (TFT) can be manufactured. Contrary to the first side 22, the glass substrate 20 may also include a second side (or B side) 24. The second side 24 is the side of the glass substrate 20 that can contact one or more transportation or handling equipment during the processing and/or manufacturing of the flat panel display.

As will be explained further below, the glass substrate 20 can be treated with an etching process, so that the second side 24 has one or more characteristics that result in comparison with untreated glass substrates or compared with conventional surface treatments. Reduced electrostatic charging of the glass substrate. One such characteristic that is changed using one or more etching processes of the present invention is the surface composition of the second side 24 of the glass substrate 20. As shown in Figure 2 (but not to scale), any suitable technique can be used to measure the surface composition from the outer surface 26 of the second side 24 to the second side 24 at one or more depths. This technique can measure the surface composition (or ratio) of the second side 24 of one or more constituent elements, which is expressed as the average value (or element ratio) of the constituent elements from the outer surface 26 to a specific depth. Some example techniques include time-of-flight secondary ion mass spectrometry (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS). In view of these measurement techniques, the measurement in the present invention can be described as "to" a specific depth. For example, the surface composition of the second side 24 to the first depth D1 can be measured. The surface composition from the outer surface 26 to the second side 24 of the second depth D2 can also be measured. In one example, the surface composition of the second side 24 can be measured to a first depth D1 of about 1 nm and a second depth D2 of about 10 nm. In other examples, the first depth D1 and the second depth D2 may be different depths measured from the outer surface 26.

In the etching process of the present invention, for certain elements existing in the glass substrate 20, the surface composition of the first depth D1 and the second depth D2 may be different. For other elements that may be present in the glass substrate 20, the surface composition to the first depth D1 and the second depth D2 may be the same or substantially the same.

In one example, the surface composition of the second side 24 can be measured to determine its aluminum/silicon (Al/Si) ratio. This ratio can be determined using any suitable technique, such as time-of-flight secondary ion mass spectrometry (TOF-SIMS), X-ray photoelectron spectroscopy (XPS), or X-ray fluorescence (XRF). X-ray fluorescence can be used to determine the bulk composition of the glass substrate 20, and time-of-flight secondary ion mass spectrometry (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS) can be used to determine the surface composition of the glass substrate 20. These techniques can be used to measure the surface composition of the second side 24 at the first depth D1 and the second depth D2. The surface composition of the second side 24 after being processed by the etching process of the present invention can be compared with the surface composition of the second side 24 that has not been processed. In this way, the difference between the surface composition of the treated second side 24 and the untreated second side 24 can be measured.

In one example, the second side 24 may have a surface composition having an Al/Si ratio in the range of 38-42% of the surface composition of the untreated glass substrate 20 with the first depth D1 to 1 nm, and The Al/Si ratio is in the range of 71-73% of the surface composition of the untreated glass substrate 20 at the second depth D2 of 10 nm. In another example, the second side 24 may have a surface composition having an Al/Si ratio in the range of 35-45% of the surface composition of the untreated glass substrate 20 at the first depth D1 of 1 nm, And the Al/Si ratio is in the range of 70-74% of the surface composition of the untreated glass substrate 20 at the second depth D2 of 10 nm. In yet another example, the second side 24 may have a surface composition having an Al/Si ratio in the range of 30-50% of the surface composition of the untreated glass substrate 20 at the first depth D1 of 1 nm , And the Al/Si ratio is in the range of 65-75% of the surface composition of the untreated glass substrate 20 at the second depth D2 of 10 nm.

In some instances, the surface composition of the second side 24 can be measured to determine its magnesium/silicon (Mg/Si) ratio. The Mg/Si ratio can be measured using one or more of the techniques described above regarding the Al/Si ratio. The second side 24 may have a surface composition having a Mg/Si ratio in the range of 72-81% of the surface composition of the untreated glass substrate 20 of the first depth D1 to 1 nm, and the Mg/Si ratio in In the range of 72-81% of the surface composition of the untreated glass substrate 20 at the second depth D2 of 10 nm. In this example, the Mg/Si ratio at the first depth D1 of 1 nm and the second depth D2 of 10 nm may be substantially the same. In another example, the second side 24 may have a surface composition having a Mg/Si ratio in the first depth D1 to 1 nm and the second depth D2 to 10 nm in the surface composition of the untreated glass substrate 20 In the range of 70 – 83% of the In yet another example, the second side 24 may have a surface composition having a Mg/Si ratio of the surface of the untreated glass substrate 20 having a first depth D1 of 1 nm and a second depth D2 of 10 nm In the range of 65-88% of the composition.

In some examples, the surface composition of the second side 24 can be measured to determine its calcium/silicon (Ca/Si) ratio. The Ca/Si ratio can be measured using one or more of the techniques described above with regard to the Al/Si ratio. The second side 24 may have a surface composition having a Ca/Si ratio in the range of 33-34% of the surface composition of the untreated glass substrate 20 of the first depth D1 to 1 nm, and the Ca/Si ratio in In the range of 77-99% of the surface composition of the untreated glass substrate 20 at the second depth D2 of 10 nm. In another example, the second side 24 may have a surface composition having a Ca/Si ratio in the range of 31-35% of the surface composition of the untreated glass substrate 20 at the first depth D1 to 1 nm, And the Ca/Si ratio is in the range of 75-99% of the surface composition of the untreated glass substrate 20 at the second depth D2 of 10 nm. In yet another example, the second side 24 may have a surface composition having a Ca/Si ratio in the range of 30-36% of the surface composition of the untreated glass substrate 20 at the first depth D1 of 1 nm , And the Ca/Si ratio is in the range of 72-99% of the surface composition of the untreated glass substrate 20 at the second depth D2 of 10 nm.

The surface composition of the second side 24 can also be measured to determine the concentration of fluorine (F) at one or more depths. The above-mentioned measurement technique can be used to determine the concentration of F in the surface composition of the second side 24. In an example, the concentration of F on the second side 24 at the first depth D1 of 1 nm may be 290-330% of the concentration of F in the untreated glass substrate 20. In another example, the concentration of F on the second side 24 at the first depth D1 of 1 nm may be 270-350% of the concentration of F in the untreated glass substrate 20.

As mentioned above, the surface composition may be described separately, but it should be understood that the surface composition of the second side 24 may have more than one or all of the aforementioned characteristics. For example, the surface composition of the second side 24 may have one or all of the above-mentioned Al/Si ratio, Mg/Si ratio, Ca/Si ratio, and F concentration. In an example, the surface composition of the second side 24 may have a first depth of 1 nm. The surface composition of the untreated glass substrate has an Al/Si ratio of 38-42%, a Mg/Si ratio of 72-81%, And the Ca/Si ratio is 33 – 34%, and the Al/Si ratio of the untreated glass substrate to the second depth of 10 nm is 71 – 73%, the Mg/Si ratio is 72 – 81%, and the Ca/Si ratio is 77-99%. This same example can also have an F concentration of 290-330% of the surface concentration of the untreated glass substrate.

The etching process of the present invention can also cause the outer surface 26 of the second side 24 to have a predetermined roughness. The roughness of the second side 24 may have a roughness (after etching) greater than the roughness of the first side 22. In an example, the roughness of the second side 24 has a roughness value Ra in the range of 0.6-1.0 nm. In another example, the second side 24 may have a roughness value Ra in the range of 0.5-1.2 nm. In other examples, other suitable roughness values can also be generated. The roughness can be measured using any suitable technique including a profilometer or the like to determine the aforementioned range.

The etching process of the present invention and the accompanying change in the surface composition and/or roughness of the second side 24 can cause a reduction in the amount of electrostatic charging that occurs on the glass substrate 20. In one example, the processed glass substrate may have at least a 50% reduction in the glass voltage compared to the glass voltage of the unprocessed glass substrate. In another example, the processed glass substrate may have at least a 60% reduction in the glass voltage compared to the glass voltage of the unprocessed glass substrate. In yet other examples, the processed glass substrate may have at least a 65% reduction in the glass voltage compared to the glass voltage of the unprocessed glass substrate.

It is expected that the etching process of the present invention will not cause side effects on the glass substrate 20. Certain etching processes can result in treated glass substrates with an unacceptable amount of haze for the treated glass substrate. The etching process of the present invention does not cause excessive haze on the processed glass substrate. That is, the absence of this etching treatment will negatively affect the haze of the glass substrate used in the flat panel display.

FIG. 3 shows an example method 300 for processing a glass substrate using the principles and teachings of the present invention. Before the step shown in Figure 3, any suitable method can be used to produce the glass substrate. In one example, a fusion stretching process is used to form the glass substrate. The glass substrate can be any suitable glass substrate used in flat panel displays. The glass substrate may be, for example, alkaline earth boroaluminosilicate glass, such as Corning's Lotus™ NXT glass.

In step 304, the glass substrate may be preheated to a predetermined etching temperature. In step 304, any suitable furnace or heating source can be used to heat the glass substrate to a predetermined etching temperature.

In step 306, the glass substrate is etched using one of the etching processes of the present invention which will be further described later. In one example, the etching process in step 306 is an Atmospheric Electric Plasma Etching (APPE) process, in which HF plasma is used to etch the second side 24 of the glass substrate 20. In this process, CF ₄ and H ₂ O can be used as precursors to produce the glass substrate 20 having the aforementioned characteristics of the second side 24. During step 306, and as further explained later, the first side of the heated glass substrate may be exposed to air, while the second side of the heated glass substrate is exposed to HF plasma to etch the second side of the glass substrate and change The surface composition of the second side forms a treated glass substrate.

After etching, in step 308, the glass substrate may be rinsed and dried. Any suitable rinsing and drying treatments can be used, such as the treatments described above or the treatments described later in relation to the efficacy test.

FIG. 4 shows an example method 400 of etching the glass substrate 20. Method 400 will further detail one or more steps that may occur during step 306 of method 300. During one or more steps of the method 400 that will be described, the etching apparatus 500 depicted in Figure 5 may be used. However, it should be understood that Figures 4 and 5 are discussed together for illustrative purposes only. The method 400 and the etching device 500 shown in FIGS. 4 and 5, respectively, can be used in implementations other than the specific examples described later.

In step 402, HF plasma can be generated by one or more plasma generators. Any suitable generator can be used. In addition, there may be two or more plasma generators fluidly coupled to mix HF plasma. In step 404, plasma may be delivered into the etching area. In step 406, the plasma may contact the glass substrate in the etched area. When the plasma contacts the glass substrate, the plasma reacts with the glass substrate to cause the aforementioned change in the surface composition of the glass substrate. In addition, the surface of the glass substrate contacted by the plasma may be roughened to have the aforementioned roughness characteristics. In step 406, the etching area may be set, for example, so that the second side 24 of the glass substrate 20 is contacted by the plasma, so that the surface composition and surface roughness are changed, while avoiding or limiting a large amount of plasma contacting the glass substrate 20. The first side 22. In this way, the second side 24 undergoes the aforementioned changes, while the first side 22 is not significantly affected by the plasma, so that the first side 22 remains suitable for the manufacture of thin film transistors to manufacture flat panel displays.

At step 408, the plasma is removed from the etched area. For example, the etching area may have an outlet channel through which the plasma can be drawn from the etching area and leave the glass substrate. In this way, the plasma can propagate through the etching zone (and contact the glass substrate) to cause etching of the glass substrate to occur.

In step 410, plasma exit data may be collected from the plasma removed from the etched area. Any suitable sensor or data processing equipment can be used. In one example, a Fourier transform infrared (FT-IR) spectrometer can be used to collect and process data on the characteristics of the plasma leaving the etching area. This data and information can be used to monitor processing and make adjustments to flow rate, plasma, glass substrate transportation rate, or other processing attributes. Although not shown, the method 400 may also include other steps. Such additional steps may include collecting data at other points in the process or washing or processing the plasma that will leave the etched area.

The steps of the method 300 and/or the method 400 may be executed by a computer-implemented program or other processing devices. Data collection and analysis can also be output to a screen or other output device. The methods and systems described herein can be at least partially embodied in the form of computer-implemented processing and equipment for performing these processing. The disclosed method can also be at least partially embodied in the form of an actual non-transitory machine-readable storage medium encoded with computer code. This medium may include, for example, RAM, ROM, CD-ROM, DVD-ROM, BD-ROM, hard disk drive, flash memory, or any other non-transitory machine-readable storage medium, or any combination of these media, Wherein, when the computer program code is loaded into the computer and executed, the computer becomes the device for implementing this method. This method can also be at least partially embodied in the form of a computer in which computer program codes are loaded and/or executed, making the computer a device for implementing this method. When implemented on a general-purpose processor, the computer code segment sets the processor to generate specific logic circuits. This method may alternatively be at least partially embodied in a digital signal processor formed by an application-specific integrated circuit used to perform this method.

Figure 5 shows an example etching apparatus 500. As shown in the figure, the etching equipment 500 may include a generator 502, a nozzle 504, and a detector 508. The etching device 500 can be used in the aforementioned method 400 in one example. The generator 502 may be any suitable generator, such as a plasma generator for generating HF plasma. In other examples, other devices for generating HF steam may also be used. The generator 502 is fluidly connected to the nozzle 504 via the input channel 512. As shown, the input channel 512 can allow the plasma to move from the generator 502 and enter the nozzle 504, as indicated by the arrow in Figure 5. The plasma is movable toward the glass substrate 20 positioned in the nozzle 504. In the illustrated example, the glass substrate 20 may be positioned such that the second side 24 of the glass substrate is opposite to the input channel 512. Therefore, when the plasma flows into the etching chamber 516, the plasma may contact the second side 24 of the glass substrate 20.

As further illustrated, the nozzle may also be fluidly connected to the outlet channel 514. The plasma can exit the etching chamber 516 through the outlet channel 514. In one example, a vacuum may be applied at the outlet channel 514 to cause the plasma to flow from the input channel 512 through the etching chamber 516 and out of the outlet channel 514. In this configuration, the second side 24 of the glass substrate 20 is exposed to the plasma so that etching of the second side 24 occurs. In the illustrated example, the glass substrate 20 may be supported in the etching chamber 516 by a roller 510. The roller 510 may be positioned at the opposite end of the etching chamber 516 and may seal the end of the etching chamber 516 to avoid and/or restrict the plasma from leaving the etching chamber. As further illustrated, the part of the second side 24 between the rollers 510 is exposed to the plasma used for etching without being supported or not contacting other intermediate members of the second side 24. This arrangement can result in uniform etching and uniform surface characteristics of the second side 24.

The aforementioned etching equipment 500 also limits and/or prevents the first side 22 of the glass substrate 20 from being exposed to a large amount of plasma or HF vapor. The first side 22 of the glass substrate 20 is exposed to the air. Although some air will flow from the first side 22 toward the second side 24 (and exit through the outlet channel 514), due to the pressure difference between the nozzle 504 area above the first side 22 and below the second side 24, The plasma is restricted from moving towards the first side 22.

As further shown, the outlet channel 514 can be connected to the detector 508. The detector 508 can be any suitable sensor and/or data collection or analysis unit. For example, the detector 508 can be a Fourier transform infrared (FT-IR) spectrometer, which can be used to collect and process data about the characteristics of the plasma leaving the etching chamber 516. In other examples, other sensors or data collection units can be used.

The implementation of the above-mentioned method and equipment will result in a glass substrate with the aforementioned characteristics. The surface composition and increased roughness will result in a glass substrate 20 with reduced electrostatic charging compared to a glass substrate etched without using the principles and teachings of the present invention. The etched glass substrate 20 of the present invention also exhibits reduced electrostatic charging and reduced friction compared to a glass substrate etched using a conventional wet etching process. One such wet etching process is a process using NaF and H ₃ PO ₄ , as described in US Patent No. 5,792,327 by Belscher et al.

Example glass substrate-performance test

Example glass substrates were etched using the dry etching, APPE treatment of the present invention, and tested to determine changes in surface characteristics and improvements caused by electrostatic charging. The test sample was prepared using Corning's Lotus™ NXT glass, which is alkaline earth boroaluminosilicate glass. The sample was manually input through dry etching, APPE processing, which was substantially similar to the aforementioned processing, and was rinsed and air knife dried without cleaning agent. For the following description, these samples are described as "APPE" samples. The APPE samples were processed so that some samples exhibited a roughness Ra of about 1.0 nm (described as "APPE 1.0"). Processing other APPE samples showed a roughness Ra of about 0.6 nm (described as "APPE 0.6").

The other control samples of this glass were processed in the manner described above, but were not processed using dry etching. For the following explanation, such samples are described as "unprocessed" samples. Other control samples of this glass were processed in the manner described above, but were etched using the wet etching process described in US Patent No. 5,792,327 to Belscher et al. For the following description, these samples are described as "wet etched" samples.

APPE samples, unprocessed samples, and wet-etched samples are packaged and vibrated to simulate the packaging and transportation of glass substrates that usually occur during the transportation of the glass substrate from the glass manufacturing facility to the subsequent manufacturing facility during the manufacturing of the flat panel display. The sample is packaged next to the interleaf wrapping paper (e.g., GCIP D paper manufactured by Tokushu Tokai Paper Co.), and then using the Telecordia GR-63 standard under ambient humidity (e.g., Telecordia GR-63 from Section 4.4.5 Transport Vibration ) The vibration lasts for 2 hours, and the pressure generated is used to simulate the pressure typically seen in general packaging and transportation. Further details of the vibration test can be seen in Figure 6, which shows the power spectral density (PSD) and frequency.

APPE samples, unprocessed samples, and wet-etched samples were then unpacked and cleaned, but were rotated, rinsed, and dried. The cleaning treatment includes cleaning the sample with 1% Semiclean KG cleaning agent (produced by Yokohama Oils and Fats Industry Co., Ltd.) at 50°C and ultrasonic cleaning the sample for 10 minutes, followed by rinsing with deionized water. It should be noted that this cleaning chemical can change the surface chemical composition of the sample.

Then, the sample was lifted and tested to determine the surface charge characteristics of the sample. When used here, the lift test refers to the test treatment of the glass substrate or glass sample described later. The lift test takes place on the vacuum chuck table of the general device used during the transportation and/or processing of the glass substrate in the flat panel display manufacturing process. The lifting test equipment is made of aluminum with insulating anodized coating and includes a square peripheral vacuum channel with a smaller square inner vacuum channel. When the glass sample is in contact with the vacuum chuck, the degree of vacuum reached is about -83 kPA. The size of the glass sample was 4 inches by 4 inches and was lowered onto and lifted from the vacuum chuck using round-head insulated Vespel pins.

The electrostatic charge is generally generated when the glass substrate is lifted and lowered from the vacuum chuck. When the glass is drawn against the suction cup, deformed near the edge of the vacuum channel, and rubbed against the edge of the suction cup, electric charge can be generated by tribo-electrification. To simulate this effect during processing, the glass sample was lowered and lifted 6 times from the vacuum chuck at a rate of 10 mm/sec. A glass voltage measuring sensor was used to measure the voltage of the glass after contact separation for 60 seconds. The glass voltage sensor is located at a distance of 10mm from the glass and tracks the movement of the glass when the glass is lifted and lowered from the vacuum chuck. The glass voltage is recorded during each cycle of the glass sample. The voltage recorded during each cycle is used to calculate the mean glass voltage. The average glass voltage for each glass sample is shown in Table 1 below. In addition, the statistical analysis of the voltage of the glass sample is shown in Figure 7, and it is shown that the APPE sample, the wet etched sample, and the untreated sample are statistically significant to each other.

Table 1-Average glass voltage of test samples Glass sample Average voltage ( volts ) APPE 1.0 sample -633.544 Wet etching samples -1026.556 Unprocessed sample -1871.550

It can also be found that the APPE sample processed by the etching process of the present invention exhibits a significant improvement in electrostatic charging compared to both the wet-etched sample and the untreated sample. The APPE sample showed a 66% improvement compared to the untreated sample and a 38% improvement compared to the wet etched sample.

The surface composition of APPE samples, wet etched samples and untreated samples were also analyzed using XPS and TOF SIMS to determine the composition of the glass surface with regard to the quantification of the main glass elements compared with silicon and the concentration of fluorine. The TOF SIMS characterization method was used to determine the surface composition of the test sample to a depth of 1 nm. The XPS characterization method was used to determine the surface composition of the test sample to a depth of 10 nm. The results of the surface composition test are shown in Table 2 below. The values of the element ratio and F concentration were also normalized for the untreated sample to show the difference from the untreated sample.

Table 2-Surface composition of test samples Characterization method Element ratio and test sample value Standardization of unprocessed samples TOF SIMS Al/Si APPE 1.0 0.38 0.38114343 Al/Si APPE 0.6 0.42 0.421263791 Al/Si wet etching 1.05 1.053159478 Al/Si untreated 0.997 1 XPS Al/Si APPE 1.0 0.222 0.720779221 Al/Si APPE 0.6 0.224 0.727272727 Al/Si wet etching 0.316 1.025974026 Al/Si untreated 0.308 1 TOF SIMS Mg/Si APPE 1.0 0.083 0.775700935 Mg /Si APPE 0.6 0.087 0.813084112 Mg /Si wet etching 0.096 0.897196262 Mg/Si untreated 0.107 1 XPS Mg/Si APPE 1.0 0.026 0.722222222 Mg/Si APPE 0.6 0.029 0.805555556 Mg/Si wet etching 0.03 0.833333333 Mg/Si untreated 0.036 1 TOF SIMS Ca/Si APPE 1.0 0.055 0.297297297 Ca/Si APPE 0.6 0.057 0.308108108 Ca/Si wet etching 0.068 0.367567568 Ca/Si untreated 0.185 1 XPS Ca/Si APPE 1.0 0.056 0.777777778 Ca/Si APPE 0.6 0.057 0.98245614 Ca/Si wet etching 0.068 0.944444444 Ca/Si untreated 0.072 1 TOF SIMS F APPE 1.0 7.44 3.263157895 F APPE 0.6 6.62 2.903508772 F wet etching 2.64 1.157894737 F untreated 2.28 1

It can be found that the APPE sample shows changes in Al/Si, Mg/Al, Ca/Si ratio and F concentration compared to the untreated sample. This change in composition and increased roughness of the glass surface can be regarded as exhibiting a reduction in electrostatic charging as previously described in Table 1.

The test sample can also be tested to determine whether the haze of the test sample increases after being subjected to the dry etching, APPE treatment of the present invention. For all samples, the haze was subjectively determined to be very low and/or non-existent. RKY Haze Gard Plus, Model 4725 was also used to measure samples. The measurements are shown in Table 3 below.

Table 3-Haze measurement of test samples Test sample Haze value (%) Air material 0 Unprocessed sample 0 APPE 1.0 sample 0.01 ± 0.03

As shown in the table, the haze did not increase significantly. The haze of APPE samples does not increase by more than 4%.

This description of the exemplary embodiment is intended to be read together with the accompanying drawings, which are regarded as part of the overall written description. In this manual, such as "below", "above", "horizontal", "vertical", "above", "below", "above", "below", "top" and "bottom" and their derivatives The relative terms of the words (eg, "horizontally", "downwardly", "upwardly", etc.) should be understood to refer to orientation as explained later or as shown in the scheme in question. These relative terms are used for convenience of description, and do not require the device to be constructed or operated in a specific orientation. Unless explicitly stated otherwise, terms such as "connected" and "interconnected" with respect to attachment, coupling, and similar words refer to the relationship in which a structure is directly or indirectly fixed to or attached to another structure through an intermediary structure, and These structures can be movably or fixedly attached or associated.

For the description from now on, it will be understood that the embodiments described later can be regarded as alternative changes and embodiments. It will also be understood that the specific items, compositions, and/or processes described herein are exemplary and should not be considered as limiting.

Unless the article clearly indicates otherwise, in the present invention, the singular forms of "a", "an", and "the" include plural forms, and reference to a specific value includes at least this specific value. When a value is expressed as an approximate value by using the prefix "about", it will be understood that this particular value forms another embodiment. When used here, "about X" (where X is a value) preferably refers to including ±10% of the stated value. For example, the phrase "about 8" preferably refers to including a value of 7.2 to 8.8. When used here, "substantially similar" preferably refers to ±10% of the value used to characterize the comparative characteristic. When present, all ranges are inclusive and combinable. For example, when referring to a range of "1 to 5", the range should be understood to include the ranges "1 to 4", "1 to 3", "1-2", "1-2 and 4-5" , "1-3 and 5", "2-5", and the like. In addition, when a list of alternatives is positively provided, the list can be interpreted as meaning that any one of the alternatives can be excluded, for example, by negatively limiting the scope of the patent application. For example, when referring to a range of "1 to 5", the range can be understood to include multiple situations so that any one of 1, 2, 3, 4, or 5 can be negatively excluded; therefore, " The expression "1 to 5" can be understood as "1 and 3-5, but not 2", or simply "not including 2". Any component, element, factor, or step that is intended to be mentioned positively herein can be explicitly excluded from the scope of the patent application, regardless of whether such component, element, factor, or step is listed as a substitute or whether it is mentioned in an isolated manner. and.

Although the formation of an exemplary embodiment has been used to describe the subject matter, it is not limited thereto. To be precise, the scope of the attached patent application should be broadly interpreted to include other variants and embodiments known to those skilled in the art.

D1: first depth D2: second depth 20: Glass substrate 22: first side 24: second side 26: outer surface 300: method 304,306,308: steps 400: method 402, 404, 406, 408, 410: steps 500: Etching equipment 502: Generator 504: Nozzle 508: Detector 510: Roller 512: input channel 514: Exit Channel 516: Etching Chamber

When read together with the accompanying drawings, the present invention can be best understood from the following embodiments. According to general implementation, it is emphasized that the various features in the diagram are not necessarily in proportion. On the contrary, the scale of various features can be arbitrarily expanded or reduced to facilitate the clarity of the illustration. Throughout the specification and drawings, the same component symbols refer to the same features.

Figure 1 is a perspective view showing an exemplary processed glass substrate according to some embodiments of the present invention.

FIG. 2 is a cross-sectional view showing various example layers of the processed glass substrate of FIG. 1. FIG.

Fig. 3 is a flowchart showing an exemplary method of producing the processed glass substrates of Figs. 1 and 2.

Fig. 4 is a flowchart showing an exemplary method of etching the glass substrates of Figs. 1 and 2.

FIG. 5 is a schematic diagram showing an example etching area that can be used to produce the processed glass substrates of FIGS. 1 and 2.

Figure 6 is a graph showing the plot of PSD and frequency. The plot of PSD and frequency shows the vibration profile of the vibration test sample before the lift test.

Figure 7 is a graph showing the glass voltage of the treated glass test sample, which shows the decrease in the glass voltage of the sample treated with the etching process of the present invention.

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20: Glass substrate

22: first side

24: second side

500: Etching equipment

502: Generator

504: Nozzle

508: Detector

510: Roller

512: input channel

514: Exit Channel

516: Etching Chamber

Claims (33)

A processed glass substrate used in a flat panel display. The processed glass substrate includes a first side and a second side. The first side is configured to hold a plurality of thin film transistors, and the second side is positioned at and On the side of the glass substrate opposite to the first side, a dry etching process was used to process the second side to change a surface composition of the second side, and the surface composition of the second side contained to about 1 nm A first depth to a first Al/Si ratio in a range from about 38% to about 42% of a surface composition of an untreated glass substrate to a first depth, and to a second depth of about 10 nm A second Al/Si ratio is in a range of about 71% to about 73% of the surface composition of the untreated glass substrate to the second depth. The processed glass substrate according to claim 1, wherein the glass substrate comprises a boroaluminosilicate glass. The processed glass substrate according to claim 1, wherein the dry etching process is an Atmospheric Paste Etching (APPE) process. The treated glass substrate according to claim 1, wherein a surface composition of the first side is substantially similar to the surface composition of the untreated glass substrate. The treated glass substrate according to claim 1, wherein the surface composition of the second side includes the surface of the untreated glass substrate with a first Mg/Si ratio to the first depth In a range of about 72% to about 81% of the composition, and the surface composition of the second side includes a second Mg/Si ratio to the second depth of the untreated glass substrate to the second depth The surface composition is in a range of about 72% to about 81%. The processed glass substrate according to claim 1, wherein the surface composition of the second side includes a first Ca/Si ratio to the first depth, and the surface of the untreated glass substrate to the first depth In a range of about 33% to about 34% of the composition, and the surface composition of the second side includes a second Ca/Si ratio to the second depth of the untreated glass substrate to the second depth The surface composition is in a range of about 77% to about 99%. The treated glass substrate according to claim 1, wherein the surface composition of the second side includes a concentration of fluorine to the first depth, and fluorine of the surface composition of the untreated glass substrate to the first depth In the range of about 290% to about 330% of the concentration. The processed glass substrate according to claim 1, wherein an average roughness Ra of the second side is in a range of about 0.6 nm to about 1 nm. The processed glass substrate according to claim 1, wherein after being lifted from a vacuum chuck for a test, an average glass voltage of the glass substrate is reduced by at least about 50% compared to an average glass voltage of the untreated glass substrate . The processed glass substrate according to claim 9, wherein after the processed glass substrate is packaged adjacent to the interleaf paper, vibrated for at least 2 hours, and cleaned with a solution containing about 1% of a cleaning agent, it exhibits This is a reduction in the average glass voltage of at least 50% compared to the average glass voltage of the untreated glass substrate. The processed glass substrate according to claim 1, wherein a haze of the processed glass substrate is greater than a haze of the unprocessed glass substrate by no more than about 10%. A processed glass substrate used in a flat panel display. The processed glass substrate includes a first side and a second side. The first side is configured to hold a plurality of thin film transistors, and the second side is positioned at and On the side of the glass substrate opposite to the first side, a dry etching process is used to process the second side to change a surface composition of the second side, the surface composition including to a first depth of about 1 nm A first Mg/Si ratio is in a range of about 72% to about 81% of a surface composition of an untreated glass substrate to the first depth, and a second Mg to a second depth of about 10 nm The /Si ratio is in a range of about 72% to about 81% of the surface composition of the untreated glass substrate to the second depth. The processed glass substrate according to claim 12, wherein an average roughness Ra of the second side is in a range of about 0.6 nm to about 1 nm. The processed glass substrate according to claim 12, wherein after being lifted from a vacuum chuck for a test, an average glass voltage of the processed glass substrate is reduced by at least about 50%. The processed glass substrate according to claim 12, wherein after the processed glass substrate is packaged adjacent to the interleaf paper, vibrated for at least 2 hours, and cleaned with a solution containing about 1% of a cleaning agent, it exhibits This is a reduction in the average glass voltage of at least 50% compared to the average glass voltage of the untreated glass substrate. The processed glass substrate according to claim 12, wherein a haze of the processed glass substrate is greater than a haze of the unprocessed glass substrate by no more than about 10%. A processed glass substrate used in a flat panel display. The glass substrate includes a first side and a second side. The first side is arranged to hold a plurality of thin film transistors. The second side is positioned at the same position as the first side. On the side of the glass substrate opposite to the side, a dry etching process is used to process the second side to change a surface composition of the second side, the surface composition including a first depth of about 1 nm. A Ca/Si ratio is in a range of about 33% to about 34% of a surface composition of an untreated glass substrate to the first depth, and the surface composition of the second side includes a composition of about 10 nm A second Ca/Si ratio of the second depth is in a range of about 77% to about 99% of the surface composition of the untreated glass substrate to the second depth. The processed glass substrate according to claim 17, wherein an average roughness Ra of the second side is in a range of about 0.6 nm to about 1 nm. The processed glass substrate according to claim 17, wherein after being lifted from a vacuum chuck for a test, an average glass voltage of the processed glass substrate is reduced by at least about 50%. The processed glass substrate according to claim 17, wherein a haze of the processed glass substrate is greater than a haze of the unprocessed glass substrate by no more than about 10%. A processed glass substrate used in a flat panel display. The glass substrate includes a first side and a second side. The first side is arranged to hold a plurality of thin film transistors. The second side is positioned at the same position as the first side. On the side of the glass substrate opposite to the side, a dry etching process is used to process the second side to change a surface composition of the second side, and the surface composition of the second side includes a first side of about 1 nm. A concentration of fluorine at a depth is in a range of about 290% to about 330% of a surface composition of an untreated glass substrate at the first depth. The processed glass substrate according to claim 21, wherein an average roughness Ra of the second side is in a range of about 0.6 nm to about 1 nm. The processed glass substrate according to claim 21, wherein after being lifted from a vacuum chuck for a test, an average glass voltage of the processed glass substrate is reduced by at least about 50%. The processed glass substrate according to claim 21, wherein a haze of the processed glass substrate is greater than a haze of the unprocessed glass substrate by no more than about 10%. A method of producing a processed glass substrate used in a flat panel display, the method comprising the following steps: Heating the glass substrate to a predetermined processing temperature; and Expose a first side of the heated glass substrate to the air, while exposing a second side of the heated glass substrate to an HF plasma to etch the second side of the glass substrate and change the second side A surface composition to form a processed glass substrate; Wherein the surface composition of the second side of the processed glass substrate includes a first depth of about 1 nm, a first Al/Si ratio, and a surface composition of an untreated glass substrate of the first depth In a range from about 38% to about 42%, and the surface composition of the second side of the processed glass substrate includes a second depth of about 10 nm, a second Al/Si ratio is to the second The depth is in a range of about 71% to about 73% of the surface composition of the untreated glass substrate. The method of claim 25, wherein the surface composition of the first side of the processed glass substrate has a surface composition that is substantially similar to the surface composition of the unprocessed glass substrate. The method of claim 25, wherein the surface composition of the second side of the processed glass substrate includes the unprocessed glass substrate having a first Mg/Si ratio to the first depth In a range of about 72% to about 81% of the surface composition, and the surface composition of the second side of the processed glass substrate includes a second Mg/Si ratio to the second depth Two depths are in a range of about 72% to about 81% of the surface composition of the untreated glass substrate. The method of claim 25, wherein the surface composition of the second side of the processed glass substrate includes the unprocessed glass substrate having a first Ca/Si ratio to the first depth In a range of about 33% to about 34% of the surface composition, and the surface composition of the second side of the processed glass substrate includes a second Ca/Si ratio to the second depth Two depths are in a range of about 77% to about 99% of the surface composition of the untreated glass substrate. The method of claim 25, wherein the surface composition of the second side of the treated glass substrate includes a concentration of fluorine to a first depth on the surface of the untreated glass substrate to the first depth The fluorine of the composition is in a range of about 290% to about 330% of a concentration. The method according to claim 25, wherein an average roughness Ra of the second side is in a range of about 0.6 nm to about 1 nm. The method according to claim 25, wherein after being lifted from a vacuum chuck, an average glass voltage of the glass substrate is reduced by at least 50% compared to an average glass voltage of the untreated glass substrate. The method according to claim 25, wherein after the processed glass substrate is packaged adjacent to the interleaf paper, vibrated for at least 2 hours, and cleaned with a solution containing about 1% of a cleaning agent, it exhibits a comparative A decrease in the average glass voltage of at least 50% of the average glass voltage on the untreated glass substrate. The method according to claim 25, wherein a haze of the processed glass substrate is greater than a haze of the untreated glass substrate by no more than about 10%.

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