Method of processing substrate and processing apparatus

Abstract

A method of processing a substrate is provided. And the substrate is a glass substrate for manufacturing a display. The method includes adsorbing a substrate to a unipolar electrostatic chuck by applying a voltage to an electrode of the unipolar electrostatic chuck, and providing an adsorption plasma at a first power. The method further includes treating the substrate in a direct current sputter deposition process and desorbing the substrate. The desorption includes generating a desorption plasma.

Description

Technical Field

[0001] Embodiments of the present invention relate to the processing of substrates, particularly to the adsorption of substrates to an electrostatic chuck and the desorption from the electrostatic chuck before and after processing. The embodiments particularly relate to the processing of glass substrates in a DC sputtering process. Background Art

[0002] Techniques for depositing layers on substrates include, for example, physical vapor deposition (PVD), chemical vapor deposition (CVD), and thermal evaporation. The coated substrates can be used in several applications and multiple technical fields. For example, substrates for displays can be coated through a PVD process such as sputtering. Some applications involve insulating panels, substrates with TFTs, displays, color filters, or the like. The coated substrates, such as substrates for displays, may include one or more material layers deposited on the substrate and located between two electrodes.

[0003] Direct current (DC) sputtering is a known method, often used for depositing materials, particularly metals, in a PVD process. In addition, pulsed DC sputtering can be used for depositing dielectric materials. Compared with radio frequency (RF) sputtering, DC sputtering may be less complex and less costly, and may provide a higher deposition rate, capable of being used with large-area substrates, and thus may be more advantageous when performing high-volume processing of substrates in a production environment.

[0004] Substrates for display manufacturing typically contain glass. Structures provided on the substrate, such as patterns for forming pixel structures, may include temperature-sensitive components, such as components containing organic substances. Therefore, when depositing layers on these structures during a PVD process, it may be necessary to control the substrate temperature to avoid exceeding a predetermined temperature threshold.

[0005] Using an electrostatic chuck to support the substrate may lead to difficulties in reliably holding the substrate and lifting the substrate from the glass. When lifting the substrate in the presence of an attractive force between the fixture and the substrate, the substrate may be damaged, for example, due to excessive force required for lifting, resulting in bending, cracking, or even breakage of the substrate.

[0006] Therefore, there is a need for methods and systems for efficiently adsorbing a substrate to a substrate carrier having an electrostatic chuck or desorbing from the substrate carrier in a DC sputtering process or apparatus. Summary of the Invention

[0007] According to one embodiment, a method for processing a substrate is described. The substrate is a glass substrate for display manufacturing. The method includes adsorbing the substrate to a monopole electrostatic chuck by applying a voltage to an electrode and providing an adsorption plasma at a first power. The method further includes processing the substrate in a DC sputtering deposition process and desorbing the substrate. Desorbing includes generating a desorption plasma.

[0008] According to a further embodiment, a processing apparatus is described. The processing apparatus includes a vacuum chamber, a DC sputtering source located within the vacuum chamber, and a substrate holder including a monopole electrostatic chuck. The substrate holder is configured to hold a large-area glass substrate within the vacuum chamber. The processing apparatus further includes a power supply device connected to the electrostatic chuck, and a controller configured to control the power of the DC sputtering source to provide an adsorption plasma at a first power, a desorption plasma at a third power, and to control the power supply device to provide a voltage to the monopole electrostatic chuck. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] For a more detailed understanding of the above features, reference may be made to specific embodiments for a more detailed description of a brief summary. The accompanying drawings are related to the embodiments and are described below:

[0010] Figure 1 Showing a substrate processing method according to one embodiment;

[0011] Figure 2 Showing a substrate processing method according to one embodiment;

[0012] Figure 3 Showing the variation of power, adsorption voltage, and gas flow over time in an exemplary deposition process; and

[0013] Figure 4 Schematically showing a processing apparatus according to one embodiment. DETAILED DESCRIPTION

[0014] Reference will now be made in detail to various embodiments, one or more examples of which are shown in the figures. In the following description of the figures, like reference numerals refer to like components. Generally, only the differences between the various embodiments are described. Each example is for illustrative purposes only and is not intended to be limiting. Additionally, features shown or described as part of one embodiment may be used or combined with other embodiments to produce further embodiments. Such modifications and variations are contemplated by the description.

[0015] Figure 1 A method 100 of processing a substrate is shown. The substrate is a glass substrate for display manufacturing. The substrate may be a large-area glass substrate. The method may include providing the substrate in a processing chamber suitable for a PVD process, particularly a DC sputtering deposition process. The substrate may be placed on a substrate support including a monopole electrostatic chuck.

[0016] According to an embodiment, the substrate may be a large-area glass substrate, such as for display manufacturing, and may preferably contain organic materials for manufacturing OLED components. Thus, the processing equipment and methods described herein can be configured to process such substrates. Specifically, according to the embodiments described herein, the processing equipment and methods are suitable for processing large-area substrates, such as substrates with an area of 1 m 2 or larger. For example, a large-area substrate may be GEN 5, corresponding to a substrate of approximately 1.4 m 2 (1.1 m x 1.3 m), GEN 7.5, corresponding to a substrate of approximately 4.39 m 2 (1.95 m x 2.25 m), GEN 8.5, corresponding to a substrate of approximately 5.5 m 2 (2.2 m x 2.5 m), or even GEN 10, corresponding to a substrate of approximately 8.7 m 2 (2.85 m x 3.05 m). Even larger generations such as GEN 11 and GEN 12 and their corresponding substrate areas can be implemented similarly. The substrate may include a thin glass plate, such as a glass plate with a thickness of 1 mm or less, particularly 0.7 mm or less.

[0017] According to an embodiment, the substrate may be an insulator, i.e., including a portion of a dielectric, such as a portion of glass, having a high resistivity of at least 10 10 Ωm under ambient conditions, such as exceeding 10 12 Ωm or even exceeding 10 14 Ωm, particularly having a resistance that prevents charge migration between one side and the other side of the substrate. A semiconductor substrate, such as a substrate containing silicon, particularly a silicon wafer, is not considered an insulator in the context of the present disclosure.

[0018] In operation 110, a voltage is applied to the electrodes of the electrostatic chuck. In operation 120, an adsorption plasma is provided, such as from a plasma source. The plasma source may be a sputtering source, such as a DC sputtering source for a DC sputtering deposition process. Operations 110 and 120 may be performed substantially simultaneously or may be performed continuously, such as applying a voltage to the electrostatic chuck before providing the plasma and maintaining the voltage, or vice versa. Performing operations 110 and 120 may cause the substrate to be adsorbed to the electrostatic chuck.

[0019] According to an embodiment, a unipolar electrostatic chuck differs from a bipolar electrostatic chuck in that a single-polarity voltage, preferably but not limited to a negative voltage, is applied to one or more electrodes of the electrostatic chuck. The unipolar electrostatic chuck may provide a longer adhesion force range than the bipolar electrostatic chuck. When a voltage is applied to the unipolar electrostatic chuck, charges of opposite polarity may be generated in the substrate. The electrostatic attraction between the opposite charges causes the substrate to be adsorbed to the chuck, thereby holding the substrate. The electrostatic chuck mentioned herein, unless otherwise specified, should be understood as a unipolar electrostatic chuck.

[0020] The step of adsorbing the substrate to the electrostatic chuck may include adsorbing the substrate to a substrate holder including the electrostatic chuck, and it should be understood that the substrate is fixed at least in one direction with reference to the electrostatic chuck. In particular, the voltage applied to the electrostatic chuck may cause the substrate to be affected by an electric field. The adsorption plasma may be conductive and have a potential, which may cause charges to accumulate on the substrate surface due to the electric field provided by the electrostatic chuck. The surface of the substrate may be the surface of the substrate opposite to the electrostatic chuck and / or the surface of the substrate in contact with the adsorption plasma. For example, if a negative voltage is applied to the electrostatic chuck, the potential of the electrostatic chuck may cause positive charges to accumulate on the substrate surface, such as the surface close to the adsorption plasma. Similarly, if a positive voltage is applied to the electrostatic chuck, the potential of the electrostatic chuck may cause negative charges to accumulate on the substrate surface. Opposite electric forces may generate an attractive force between the substrate and the electrostatic chuck and / or the substrate holder.

[0021] The adsorption plasma may be provided by a sputtering source, such as a DC sputtering source and / or a pulsed DC sputtering source. Using a sputtering source to generate the adsorption plasma helps to simplify the equipment for performing the method.

[0022] The adsorption plasma may be provided at a first power, and the first power is a low power. Specifically, the adsorption plasma is generated in such a way that essentially no or only limited sputtering occurs from the target of the DC sputtering source. This can help prevent unwanted material deposition, for example, when the deposition process has not been started and / or the substrate is not fully ready for the DC sputtering deposition process, such as when the substrate is not aligned, not adsorbed to the electrostatic chuck, not cooled, or otherwise not in a stable state.

[0023] In operation 130, the substrate is processed in a DC sputtering deposition process. The DC sputtering deposition process may be carried out at a second power, and the second power may be higher than the first power. According to certain embodiments, which may be combined with other embodiments described herein, the first power, the second power, and the third power for desorption may be provided in the manner Figure 3 described.

[0024] According to these embodiments, the DC sputtering deposition process can be a process suitable for depositing materials at high speed, particularly suitable for forming thick layers of low-resistance metals, with deposition speeds especially achievable exceeding Exceeding For example Even exceeding

[0025] According to these embodiments, the DC sputtering deposition process can be a deposition process suitable for depositing a material layer on a substrate, particularly a thick layer, preferably with the thickness of the deposited layer exceeding Exceeding Exceeding Exceeding Exceeding Exceeding Exceeding Exceeding Even several μm, for example exceeding 1 μm or even exceeding 2 μm.

[0026] According to the embodiments, the DC sputtering deposition process can include deposition, particularly sputtering of materials suitable for use in the DC sputtering deposition process, such as conductive materials like metals. In particular, the DC sputtering deposition process can include depositing metals, particularly low-resistance metals suitable for forming thick low-resistance layers, such as aluminum (Al), copper (Cu), and / or molybdenum (Mo). Additionally, or as an alternative, the DC sputtering deposition process can be a pulsed DC sputtering deposition process. Thus, in a pulsed sputtering deposition process, even dielectric materials, such as aluminum oxide (Al2O3), can be deposited.

[0027] In operation 140, the substrate is desorbed. Desorbing includes generating a desorption plasma at a third power. Operation 140 can further include changing the voltage applied to the electrostatic chuck electrode and can include not providing a voltage to the electrostatic chuck electrode, such as discharging, de-energizing, or grounding the electrostatic chuck.

[0028] In operation 140, the charge accumulated on the substrate surface can be released by the desorption plasma. The operation may include providing the desorption plasma until the charge of the substrate is reduced to a level where a significant electrostatic force is not generated between the substrate and the substrate holder. When there is no or almost no attraction between the substrate and the substrate holder, the substrate can be considered desorbed, or when the attraction between the substrate and the electrostatic chuck is low enough not to cause damage to the substrate when lifting the substrate.

[0029] According to various embodiments, the desorption plasma can be provided by the same plasma source as the adsorption plasma. According to various embodiments, the desorption plasma can be generated in substantially the same manner as the adsorption plasma. According to various embodiments, the desorption plasma can be provided at a third power, which is a low power, particularly a power lower than the second power. In particular, the desorption plasma should be generated such that the target of the DC sputtering source is hardly sputtered or only sputtered to a limited extent. According to various embodiments, the first power and the third power can be substantially the same power.

[0030] Now referring Figure 2 , a method 200 for processing a substrate according to various embodiments will be described.

[0031] Operations 210 to 240 can include the operations performed in method 100 described in Figure 1 , particularly in operations 110 to 140. In operations 210 and 220, the substrate is adsorbed to a monopole electrostatic chuck. In operation 210, a voltage is applied to the electrode of the electrostatic chuck. In operation 220, an adsorption plasma is provided at a first voltage.

[0032] Method 200 can include, for example, providing a cooling gas between the substrate and the electrostatic chuck after operations 210 and / or 220. For example, the cooling gas can be introduced through a conduit in the substrate holder, such as a nozzle or a channel, to the back surface of the substrate, that is, into the space formed between the substrate holder and / or the electrostatic chuck and the substrate. Preferably, the cooling gas is applied when the substrate is adsorbed (i.e., the relationship between the electrostatic chuck and / or the substrate holder remains substantially fixed).

[0033] According to an embodiment, the cooling gas can be introduced under a controllable pressure and / or a controllable gas flow, such as a constant pressure and / or a constant gas flow. For example, the pressure of the cooling gas can be controlled and limited to a predetermined value, such as a value of about 2 mbar, or even higher than 2 mbar. The pressure of the cooling gas can, to a certain extent, offset the attraction force generated by adsorbing the substrate to the electrostatic chuck. Therefore, the cooling gas can form an air cushion on the back surface of the substrate. The gas flow and / or the pressure of the cooling gas can be set to a value sufficient to cool the substrate during the processing, such as the DC sputtering deposition process in operation 230. For example, the gas flow and / or the pressure of the cooling gas can be set to a value sufficient to keep the substrate temperature below 100 °C, below 90 °C, or even 80 °C or lower during the DC sputtering deposition process at the second power.

[0034] According to an embodiment, introducing the cooling gas while adsorbing the substrate in operations 210 and 220 may include allowing the gas flow and / or the pressure of the cooling gas to stabilize, such as forming a stable air cushion.

[0035] According to an embodiment, the cooling gas can be an inert gas and / or a noble gas. Specifically, the cooling gas can be a gas suitable for being provided in a processing chamber for DC sputtering, such as helium (He), neon (Ne), argon (Ar), xenon (Xe), and / or a mixture thereof. Thus, the cooling gas entering the processing chamber can advantageously be compatible with the DC sputtering process and / or not interfere with the DC sputtering deposition process and / or the generation of adsorption plasma and desorption plasma.

[0036] In operation 230, the substrate is processed in a DC sputtering deposition process at a second power. Preferably, the DC sputtering deposition process is started after the gas flow and / or pressure of the cooling gas is stabilized.

[0037] In operation 240, the substrate is desorbed. Desorbing the substrate may include maintaining the flow of the cooling gas, or may include restricting or even stopping the flow of the cooling gas. Desorption includes generating desorption plasma. During desorption, the pressure of the cooling gas in the space between the substrate and the electrostatic chuck may contribute to desorbing and / or lifting the substrate.

[0038] According to an embodiment, method 200 may include operation 250, which can be performed simultaneously with providing the desorption plasma in operation 240, or even before providing the desorption plasma. In operation 250, a reverse voltage is applied to the electrostatic chuck. The reverse voltage is a voltage having a polarity opposite to the voltage provided to the electrodes of the electrostatic chuck in operation 210, for example, with respect to the ground potential. The reverse voltage can be equal to or lower than the voltage provided in operation 210. The application time of the reverse voltage can be shorter than the time of the desorption plasma, especially to avoid re-adsorbing the substrate with the reverse voltage. The reverse voltage can promote the lifting of the substrate from the substrate carrier by generating a repulsive force when residual charges are retained on the substrate surface, for example, through lift pins. Additionally, or alternatively, the reverse voltage can accelerate the neutralization of the surface charges of the substrate by attracting oppositely charged ions from the desorption plasma.

[0039] According to these embodiments, method 200 may include operation 260, which can be performed simultaneously with operation 250, or subsequently after operation 250. In operation 260, the substrate is lifted from the monopole electrostatic chuck and / or the substrate holder. Lifting the substrate can be understood as separating the substrate from the holder, for example, in order to transfer the substrate from the processing equipment to another equipment and / or chamber. Lifting the substrate may be a process independent of desorbing the substrate. In particular, desorbing the substrate can be understood as creating conditions under which the substrate can be lifted, especially without causing damage to the substrate. For example, lifting an unde-sorbed substrate may require the lift assembly to overcome a large amount of force, thus potentially damaging the substrate. According to these embodiments, lifting the substrate may include using lift pins to lift the substrate, such as lift pins provided within the substrate holder.

[0040] According to these embodiments, method 100 and / or 200 may include processing a substrate in a vacuum chamber. The vacuum chamber may have a low-pressure gas environment suitable for a DC sputtering deposition process. In particular, the gas environment may contain or substantially contain one or more noble gases and / or inert gases, such as He, Ne, Ar, and Xe. The pressure of the gas environment may be between 0.1 Pa and 1 Pa. In particular, the pressure of the gas environment may be higher than the pressure typically used in an RF sputtering deposition process.

[0041] According to these embodiments, during the DC sputtering deposition of operations 130 and 230, the pressure of the system may be between 0.1 Pa and 1 Pa. Preferably, methods 100 and 200 may be performed in a pressure range of 0.1 Pa to 1 Pa, including adsorption and desorption. This can effectively implement the production process because ventilation and pumping steps can be omitted, for example, before and after substrate loading or unloading.

[0042] According to an embodiment, the DC sputtering deposition, such as that performed in operations 130 and 230, may include the deposition of metallic materials, such as Al, Cu, Mo. Additionally, or alternatively, the DC sputtering deposition process may include the deposition of dielectric materials, such as Al2O3. For example, the DC sputtering deposition process may be a reactive sputtering process performed in a reactive gas environment, such as a gas environment containing an oxygen (O) species, such as an Ar gas environment containing O2. Thus, operations 130 and 230 may include a pulsed DC sputtering deposition process. According to certain embodiments, which may be combined with other embodiments described herein, processing the substrate may include depositing at least one material selected from the group consisting of low-impedance metals suitable for forming thick layers, Al, Cu, Mo, and Al2O3. For the low-impedance metals Al, Cu, and Mo, a deposition rate of more than may be provided. The deposition rate for Al2O3 may be lower.

[0043] Now referring to Figure 3 , an exemplary deposition process 300 utilizing a method according to an embodiment is described. FIG. 310 shows the power applied to a DC sputtering deposition source over time t. FIG. 320 shows the voltage applied to a monopole electrostatic chuck over time t. FIG. 330 shows the flow rate of a cooling gas over time t. Intervals i1 - i6 of different process stages are shown in the figure. These intervals and / or the changes between the intervals may correspond to the operations of the method according to the embodiments described herein. It is noted that the graphs may not be drawn to scale, i.e., some intervals may be depicted as longer or shorter than the intervals of the implemented production process.

[0044] Within interval i1, a substrate has been loaded onto a substrate holder with an electrostatic chuck. Within interval i2, a voltage U1 is applied to the electrodes of the electrostatic chuck, and an adsorption plasma is generated by starting a DC sputtering source at a first power P1. The voltage U1 can be a voltage in the range between 1 kV and 5 kV, for example, a voltage between 1.5 kV and 3 kV, or a voltage of about 2 kV. The first power P1 can be a low power of about 100 W to about 5 kW, for example, a power between about 500 W and 2 kW, or a power of about 1 kW. The first power P1 may vary according to the type and / or structure of the DC sputtering deposition source and can be adjusted accordingly. In particular, the first power P1 can be selected to be sufficient to start and maintain the plasma, but low enough not to cause unwanted deposition and / or heating on the substrate. Within interval i2, the substrate may be adsorbed to the electrostatic chuck.

[0045] Within interval i3, a cooling gas is introduced into the space between the electrostatic chuck and the substrate, in particular to form a buffer layer of the cooling gas between the back surface of the substrate and the substrate holder including the electrostatic chuck. Within interval i3, a cooling gas flow may be established and / or stabilized, for example, by maintaining the cooling gas flow at a constant pressure and / or a constant flow rate. As shown in FIG. 330 of Figure 3 a constant cooling gas flow rate Q1 can be maintained by controlling the cooling gas supply. In addition, in some embodiments, a constant cooling gas pressure can also be maintained, for example, a pressure of about 2 mbar. In embodiments where a constant pressure is maintained, the cooling gas flow rate may decrease over time, for example, due to the increasing attraction between the electrostatic chuck and the substrate over time. Similarly, in embodiments where a constant cooling gas flow rate is maintained, the pressure of the cooling gas may increase over time. Either or both of the cooling gas flow rate and / or the cooling gas pressure can indicate the adsorption efficiency.

[0046] Within interval i4, a material is deposited onto the substrate by DC sputtering deposition. The DC sputtering deposition process can be carried out at a second power P2. The second power may be high enough to result in a deposition rate exceeding exceed for example, in the case of or even exceeding the case.

[0047] According to an embodiment, the second power may be higher than the first power P1, for example, more than 10 times, more than 20 times, more than 30 times, more than 40 times, or even more than 50 times. For example, in a given embodiment, DC sputter deposition may be performed within a power range of several kilowatts or dozens of kilowatts, such as in the range of about 1 kW to about 100 kW. For those skilled in the art, the power values and / or voltages given here can be adjusted according to the specific equipment and / or process used to perform the method, and the values provided here are only examples.

[0048] In interval i5, the cooling gas flow is stopped, while the adsorption voltage remains unchanged, and DC sputter deposition continues. Interval i5 can be chosen to be short enough to avoid overheating of the substrate. It should be noted that although the cooling gas flow is 0, there may still be a gas buffer layer between the electrostatic chuck and the substrate. The gas buffer layer may have a measurable pressure, for example, measured by a pressure sensor.

[0049] According to an alternative embodiment, in interval i5, the deposition can be stopped, that is, the power applied to the DC sputter deposition source can be 0.

[0050] In interval i6, the electrostatic chuck is de-energized, that is, the voltage applied to the electrostatic chuck electrode is 0. A desorption plasma is applied at a low power P1. Applying the desorption plasma may allow the substrate to discharge, so that the substrate is detached from the electrostatic chuck. Therefore, the pressure of the air cushion may be reduced. The reduction of the air cushion pressure can be used to detect whether the substrate has been sufficiently desorbed. Therefore, the desorption plasma can be provided until it is detected that the substrate has been desorbed. After the substrate is desorbed in interval i6, the desorption plasma stops, and the substrate can be lifted from the substrate carrier, for example, by activating a lift pin.

[0051] Now referring to Figure 4 , a schematic processing device 400 is described. The processing device 400 can be operated according to the method described herein. The processing device 400 can be configured to perform the method of processing a substrate according to the embodiments described herein. It should be noted that Figure 4 the processing device 400 shown in

[0052] The processing apparatus includes a vacuum chamber 410. The vacuum chamber may be configured to provide and / or maintain a gas environment suitable for processing a substrate, such as substrate 424, in a DC sputter deposition process. The gas environment may be the gas environment described with reference to method 100 and / or 200, such as an Ar gas environment at a pressure of 0.1 Pa to 1 Pa. The gas environment may be provided and / or maintained by a gas supply, such as gas supply 440. The gas supply 440 may be fluidly connected to the vacuum chamber to supply a processing gas to the vacuum chamber. The gas supply 440 may include a vacuum pump and may be configured to introduce a gas, such as Ar, to maintain the gas environment within the vacuum chamber 410.

[0053] According to an embodiment, the vacuum chamber may include chamber walls. One or more of the chamber walls may be connected to a ground potential. A plasma, such as an adsorption plasma and / or a desorption plasma, may be electrically connected to the ground potential of one or more of the chamber walls. Thus, during adsorption and / or desorption processes, for example, the plasma may be at a ground potential. During the adsorption process, ions in the plasma may be attracted to the substrate by the electric field generated by the electrostatic chuck and accumulate on the front surface of the substrate. Similarly, during the desorption process, residual charges present on the substrate surface may be neutralized by the plasma, for example because the plasma effectively forms an electrical connection between one or more grounded chamber walls and the charged surface of the substrate.

[0054] The processing apparatus 400 includes a DC sputter source 470. The DC sputter source 470 is disposed within the vacuum chamber and may be configured to sputter deposit a material onto the substrate 424 in a DC sputter deposition process. The DC sputter source may be a DC sputter source known in the art. The DC sputter source 470 may include a magnetron assembly 474 and a target 472. Although the DC sputter source 470 is depicted in Figure 4 as a source suitable for use with a disk-shaped target, the DC sputter source 470 may equally be a DC sputter source utilizing a rotatable target and / or cathode. Similarly, more than one DC sputter source may be provided.

[0055] As Figure 4 shown, the DC sputter source 470 is connected to a controller 460. Although the connection of the DC sputter source 470 to the controller 460 is depicted in Figure 4 as a direct connection, the controller 460 may also be indirectly connected to the DC sputter source 470, for example by being connected to a power supply system (not shown) that powers the DC sputter source 470.

[0056] The processing apparatus includes a substrate holder 420 disposed within the vacuum chamber. The substrate holder includes a monopole electrostatic chuck 422. The substrate holder is configured to hold a substrate 424, particularly a large-area glass substrate, such as a substrate having an area of 1 m 2or more substrates. The substrate holder 420 can be substantially square or rectangular to support a substantially square or rectangular substrate. As Figure 4 shown, the substrate 424 can be mounted on the substrate holder 420 in a substantially horizontal position. According to an embodiment, the substrate holder 420 can include an edge support portion (not shown) for example to support and / or fix the substrate in the correct position and / or to prevent the substrate from moving within the horizontal plane.

[0057] The electrostatic chuck 422 is connected to a power supply 450, particularly electrically. The power supply 450 can be configured to provide a voltage to one or more electrodes of the electrostatic chuck 422. The voltage can be sufficient to attract the substrate to the electrostatic chuck. The power supply can further be configured to de-energize the electrostatic chuck 422 during desorption or even apply a reverse voltage. The power supply 450 can be connected to a controller 460, such as communicatively.

[0058] As Figure 4 shown, the processing apparatus 400 includes a controller 460. The controller 460 is configured to control the power of the DC sputtering source 470. As Figure 1 and Figure 2 described, the DC sputtering source 470 can be configured to operate at different powers. In particular, the DC sputtering source 470 can operate at a first power to generate an adsorption plasma. The DC sputtering source 470 can operate at a second power during a DC sputtering deposition process. The DC sputtering source 470 can operate at a third power to generate a desorption plasma. Thus, the controller 460 can be configured to cause the DC sputtering source 470 to operate at the first power, the second power, and / or the third power. For example, the controller 460 can be configured to control the power supply of the DC sputtering source 470. The second power can be higher than the first power and / or the third power, e.g., as referenced Figure 3 described. The controller 460 can be configured to control the DC sputtering source 470 according to a processing sequence, e.g., operating at the first power to generate an adsorption plasma when adsorbing the substrate 424, operating at the second power during a DC sputtering deposition operation, and / or operating at the third power to generate a desorption plasma during the desorption of the substrate 424.

[0059] The controller 460 is connected to the power supply 450 to control the power supply 450 to provide a voltage to the monopole electrostatic chuck 422. The controller 460 can be configured to control the power supply 450 according to a process sequence, e.g., providing a voltage to the electrostatic chuck 422 during the adsorption and processing of the substrate 424 and / or removing the power supply of the electrostatic chuck 422 during the desorption, lifting, loading, and / or unloading of the substrate 424.

[0060] According to an embodiment, as Figure 4As shown, the processing device 400 can be configured to provide a cooling gas to cool the substrate 424, especially during a DC sputtering deposition process. During Figure 4 In the example shown, the substrate holder 420 includes conduits 428. These conduits are fluidly connected to a cooling gas supply 434 through cooling gas connections 430. The conduits 428 may include a plurality of openings within the substrate holder 420. Although only two conduits 428 are shown in Figure 4 , the substrate holder 420 may include a plurality of conduits 428, such as 10 or more conduits, or even 50 or more conduits. The cooling gas supplied through the conduits 428 allows the cooling gas to be introduced between the electrostatic chuck 422 and the substrate 424, such as the back side of the substrate 424. The cooling gas may flow along the back side of the substrate 424 towards the edge of the substrate, thereby cooling the substrate.

[0061] The cooling gas supply 434 can be fluidly connected to the conduits 428 through a valve 432. The valve 432 can be controlled by a controller 460. The controller 460 can be configured to control the flow rate and / or pressure of the cooling gas introduced between the monopole electrostatic chuck 422 and the substrate 424, such as by actuating the valve 432. According to an embodiment, a flow sensor and / or a pressure sensor may be provided to sense the flow rate and / or pressure of the cooling gas. The controller 460 can be configured to provide the cooling gas at a constant flow rate and / or a constant pressure.

[0062] According to various embodiments, the controller 460 can be configured to determine the adsorption efficiency based on the readings of the flow sensor and / or the pressure sensor. For example, the attraction between the substrate 424 and the electrostatic chuck 422 may cause a pressure, such as a back pressure, to be generated in the space between the substrate 424 and the electrostatic chuck 422. Therefore, the pressure signal provided by the pressure sensor may be related to the flow signal provided by the flow sensor, which can indicate whether the substrate has been adsorbed onto the electrostatic chuck and / or whether the substrate has been desorbed.

[0063] According to various embodiments, as Figure 4 shown, the device 400 may include a lift pin assembly including lift pins 426. The lift pin assembly can be configured to lift the substrate 424 after the DC sputtering deposition process of the substrate 424 is completed. The lift pins 426 are partially disposed within the substrate holder 420. The controller 460 can be configured to control the lift pin assembly to lift the substrate 424 after the substrate is desorbed, especially when the risk of damage due to the remaining attraction is reduced.

[0064] The methods and apparatuses described herein facilitate the efficient adsorption of a glass substrate to and desorption from a monopole electrostatic chuck in a DC sputter deposition process. In particular, the substrate can be loaded, adsorbed, processed, desorbed, and unloaded without changing the gas environment within the processing chamber (i.e., without purging the chamber after processing), which helps to increase the processing speed and reduce costs.

[0065] While the foregoing is directed to certain embodiments, other further embodiments can be devised without departing from the basic scope, which is determined by the claims that follow.

Claims

1. A method of processing a substrate, the substrate being a glass substrate for display manufacturing; the method comprising: adsorbing the substrate to a monopole electrostatic chuck by the following operations: - applying a voltage to an electrode of the electrostatic chuck, and - providing an adsorption plasma at a first power; processing the substrate in a DC sputtering deposition process; and desorbing the substrate, the desorption including generating a desorption plasma.

2. The method according to claim 1, wherein the adsorption plasma is provided by a sputtering source of the DC sputtering process, and wherein the DC sputtering deposition process is carried out at a second power higher than the first power.

3. The method according to claim 2, wherein the desorption plasma is provided at a third power lower than the second power.

4. The method according to any one of the preceding claims, wherein desorbing the substrate includes applying a reverse voltage to the electrode of the electrostatic chuck.

5. The method according to any one of the preceding claims, wherein the processing includes providing a cooling gas between the substrate and the electrostatic chuck.

6. The method according to claim 5, wherein the cooling gas is a noble gas, particularly selected from the group consisting of He, Ne, Ar, and Xe.

7. The method according to any one of the preceding claims, wherein the DC sputtering includes pulsed DC sputtering.

8. The method according to any one of the preceding claims, further comprising: After desorbing the substrate, lift the substrate from the monopole electrostatic chuck.

9. The method according to claim 8, wherein lifting the substrate includes using lift pins to lift the substrate.

10. The method according to any one of the preceding claims, wherein processing the substrate comprises depositing a material at a rate exceeding .

11. The method according to any one of the preceding claims, wherein processing the substrate includes depositing a material selected from the group consisting of: low-impedance metals suitable for forming thick layers, Al, Cu, Mo, and Al2O3.

12. The method according to any one of the preceding claims, wherein processing the substrate includes maintaining a pressure of 0.1 Pa to 1 Pa in a vacuum chamber to process the substrate.

13. The method according to any one of the preceding claims, wherein the method is carried out at a pressure of 0.1 Pa to 1 Pa.

14. The method according to any one of the preceding claims, wherein the method is carried out in a gas environment including Ar.

15. A processing apparatus, comprising: a vacuum chamber; a DC sputtering source located within the vacuum chamber; a substrate holder including a monopole electrostatic chuck, the substrate holder configured to hold a large-area glass substrate within the vacuum chamber; a power supply connected to the electrostatic chuck; a controller configured to: control the power of the DC sputtering source to provide an adsorption plasma at a first power and a desorption plasma at a third power, and control the power supply to apply a voltage to the monopole electrostatic chuck.

16. The processing apparatus according to claim 15, wherein the substrate holder includes a conduit for introducing a cooling gas between the monopole electrostatic chuck and the substrate.

17. The processing apparatus according to claim 16, wherein the controller is configured to supply the cooling gas at a constant flow rate and / or a constant pressure.

18. The processing apparatus according to claim 16 or 17, wherein the cooling gas is a noble gas, particularly selected from the group consisting of He, Ne, Ar, and Xe.

19. The processing apparatus according to any one of claims 15 to 18, wherein the DC sputtering source is configured to deposit material at a rate exceeding .

20. The processing apparatus according to any one of claims 15 to 19, wherein the DC sputtering source includes a target, and the target is selected from the group consisting of the following materials: low-resistance metals suitable for forming thick layers, Al, Cu, and Mo.

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