Systems and methods for UV-based suppression of plasma instabilities

Abstract

The present invention relates to a system and method for UV-based suppression of plasma instabilities. A substrate is positioned to be exposed to a plasma generation region within a plasma processing chamber. A first plasma is generated within the plasma generation region. The first plasma is configured to cause a film to be deposited on the substrate until the film deposited on the substrate reaches a threshold film thickness. The substrate is then exposed to ultraviolet radiation to eliminate defects in the film deposited on the substrate. The ultraviolet radiation can be provided in situ using a second plasma configured to generate ultraviolet radiation or using an ultraviolet radiation device configured to be exposed in the plasma generation region. The ultraviolet radiation can also be provided ex situ by moving the substrate to an ultraviolet radiation device separate from the plasma processing chamber. The substrate can be exposed to ultraviolet radiation in a repeated manner to eliminate defects in the deposited film as the film thickness increases.

Description

[0001] This application is a divisional application of an invention patent application with a filing date of September 11, 2017, Chinese patent application number 201710811367.5, and invention name “System and method for UV-based suppression of plasma instability”. Technical Field

[0002] The present invention relates to semiconductor device manufacturing. Background Art

[0003] Many modern semiconductor chip manufacturing processes include the generation of plasmas, from which ions and / or radical components are used to directly or indirectly affect changes on the surface of a substrate exposed to the plasma. For example, various plasma-based processes can be used to etch material from a substrate surface, deposit material onto a substrate surface, or modify material already present on a substrate surface. Plasma is typically generated by applying radio frequency (RF) power to a process gas in a controlled environment so that the process gas is excited and converted into a desired plasma. The characteristics of the plasma are affected by many process parameters, including but not limited to the material composition of the process gas, the flow rate of the process gas, the geometric features of the plasma generation region and surrounding structures, the temperature of the process gas and surrounding materials, the frequency and amplitude of the applied RF power, and the bias voltage applied to attract the charged components of the plasma toward the substrate.

[0004] However, in some plasma processes, the above process parameters may not provide adequate control of all plasma characteristics and behaviors. Specifically, in some plasma processes, an instability called a "plasmoid" may occur within the plasma, wherein the plasma cluster is characterized by a small area of ​​high density plasma surrounded by a larger volume of normal density plasma. The formation of a plasma cluster can lead to non-uniformity of processing results on the substrate. Therefore, it is meaningful to mitigate and / or control the formation of a plasma cluster. It is in this context that the present invention was created. Summary of the invention

[0005] In an exemplary embodiment, a method is disclosed for in-situ treatment of film surface defects during a plasma-based film deposition process. The method includes positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber. The method also includes generating a first plasma within the plasma generation region. The first plasma is configured to cause film deposition on the substrate. The method also includes generating a second plasma within the plasma generation region. The second plasma is configured to emit ultraviolet radiation within the plasma generation region. The substrate is exposed to the ultraviolet radiation. The ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate.

[0006] In an exemplary embodiment, a method is disclosed for in-situ treatment of film surface defects during a plasma-based film deposition process. The method includes positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber. The method also includes generating a first plasma within the plasma generation region. The first plasma is configured to cause a film to be deposited on the substrate. The first plasma is generated until the film deposited on the substrate reaches a threshold film thickness. The method also includes stopping generating the first plasma when the film deposited on the substrate reaches the threshold film thickness, and generating a second plasma within the plasma generation region. The second plasma is configured to emit ultraviolet radiation within the plasma generation region, exposing the substrate and the film deposited on the substrate to the ultraviolet radiation. The ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects within the film on the substrate. The method also includes stopping generating the second plasma in operation a). The method then proceeds to operation b), in which the generation of the first plasma within the plasma generation region is resumed until the interval thickness of the film deposited on the substrate reaches the threshold film thickness. The interval thickness of the film corresponds to the thickness of the film deposited since the generation of the second plasma was most recently stopped. When the interval thickness of the film deposited on the substrate reaches the threshold film thickness, the method then proceeds to operation c), in which the generation of the first plasma is stopped, and the generation of the second plasma in the plasma generation region is resumed, and the defects in the film on the substrate are eliminated using the ultraviolet radiation from the second plasma. The method also includes repeating operation a), operation b) and operation c) in a continuous manner until the film deposited on the substrate reaches a fixed film thickness.

[0007] In an exemplary embodiment, a method is disclosed for ex-situ treatment of film surface defects during a plasma-based film deposition process. The method includes: positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber. The method also includes: generating a plasma within the plasma generation region. The plasma is configured to cause a film to be deposited on the substrate. The plasma is generated until the film deposited on the substrate reaches a threshold film thickness. The method also includes: when the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the plasma and moving the substrate to an ultraviolet radiation device configured to generate ultraviolet radiation. The method includes: exposing the substrate and the film deposited on the substrate to the ultraviolet radiation. The ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate. The method also includes operation a), in which the substrate is repositioned to be exposed to the plasma generation region within the plasma processing chamber. The method proceeds to operation b), in which the generation of the plasma in the plasma generation region is resumed until the interval thickness of the film deposited on the substrate reaches the threshold film thickness. The interval thickness of the film corresponds to the thickness of the film deposited since the substrate was most recently exposed to ultraviolet radiation in the ultraviolet radiation device. When the interval thickness of the film deposited on the substrate reaches the threshold film thickness, the method includes operation c), in which the generation of the plasma is stopped, the substrate is moved to the ultraviolet radiation device, and the substrate and the film deposited on the substrate are exposed to the ultraviolet radiation to eliminate defects in the film on the substrate. The method also includes repeating operation a), operation b) and operation c) in a continuous manner until the film deposited on the substrate reaches a fixed film thickness.

[0008] In an exemplary embodiment, a method is disclosed for in-situ treatment of film surface defects during a plasma-based film deposition process. The method includes: positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber. The method also includes: generating a plasma within the plasma generation region. The plasma is configured to cause a film to be deposited on the substrate. The plasma is generated until the film deposited on the substrate reaches a threshold film thickness. When the film deposited on the substrate reaches the threshold film thickness, the method includes: stopping the generation of the plasma, and operating an ultraviolet radiation device exposed to the plasma generation region to transmit ultraviolet radiation through the plasma generation region, exposing the substrate and the film deposited on the substrate to the ultraviolet radiation. The ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate. The method then proceeds to operation a), in which the operation of the ultraviolet radiation device is stopped. The method then proceeds to operation b), in which the generation of the plasma in the plasma generation region is resumed until the interval thickness of the film deposited on the substrate reaches the threshold film thickness. The interval thickness of the film corresponds to the thickness of the film deposited since the most recent cessation of operation of the ultraviolet radiation device. When the interval thickness of the film deposited on the substrate reaches the threshold film thickness, the method then proceeds to operation c), in which the generation of the plasma is stopped, and the operation of the ultraviolet radiation device exposed to the plasma generation region is resumed to transmit ultraviolet radiation through the plasma generation region to eliminate defects in the film on the substrate. The method includes repeating operation a), operation b) and operation c) in a continuous manner until the film deposited on the substrate reaches a fixed film thickness.

[0009] In an exemplary embodiment, an apparatus for in-situ treatment of film surface defects during a plasma-based film deposition process is disclosed. The apparatus includes: a substrate support having a top surface configured to support a substrate during a plasma processing operation to deposit a film on the substrate. The apparatus also includes: an electrode configured to transmit radio frequency power into a plasma generation region covering the substrate support. The apparatus also includes: a process gas delivery component configured to deliver process gas to the plasma generation region. The apparatus also includes: an exhaust outlet configured to exhaust gas from the plasma generation region. The apparatus also includes: an ultraviolet radiation device configured to transmit ultraviolet radiation through the plasma generation region in a direction toward the top surface of the substrate support.

[0010] Specifically, some aspects of the present invention can be described as follows:

[0011] 1. A method for in-situ treatment of film surface defects during a plasma-based film deposition process, comprising:

[0012] positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber;

[0013] generating a first plasma within the plasma generating region, the first plasma configured to cause film deposition on the substrate; and

[0014] A second plasma is generated within the plasma generation region, the second plasma being configured to emit ultraviolet radiation within the plasma generation region, wherein the substrate is exposed to the ultraviolet radiation, and wherein the ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects within the film on the substrate.

[0015] 2. The method of clause 1, wherein the first plasma and the second plasma are generated simultaneously in the plasma generation region.

[0016] 3. The method of clause 1, wherein the second plasma is generated in the plasma generation region after the film deposited on the substrate reaches a threshold film thickness.

[0017] 4. The method of clause 3, wherein the second plasma is continuously generated in the plasma generation region as the thickness of the film deposited on the substrate grows from the threshold film thickness to a fixed film thickness.

[0018] 5. The method of clause 4, wherein the threshold film thickness is within a range extending up to approximately 75 Angstroms, and wherein the fixed film thickness is within a range greater than or equal to approximately 180 Angstroms.

[0019] 6. The method of clause 1, wherein the first plasma is generated using a process gas composition of argon and oxygen, and wherein the second plasma is generated using a process gas of helium.

[0020] 7. The method of clause 6, wherein the film deposited on the substrate is a silicon dioxide film.

[0021] 8. The method of clause 1, wherein defects within the film on the substrate include oxygen vacancies and / or trapped charges.

[0022] 9. The method of clause 1, wherein the reaction on the substrate caused by the ultraviolet radiation eliminates defects within a film on the substrate through one or more processes of passivation and charge neutralization.

[0023] 10. A method for in-situ treatment of film surface defects during a plasma-based film deposition process, comprising:

[0024] a) positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber;

[0025] b) generating a first plasma within the plasma generating region, the first plasma being configured to cause a film to be deposited on the substrate, wherein the first plasma is generated until the film deposited on the substrate reaches a threshold film thickness;

[0026] c) when the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the first plasma and generating a second plasma in the plasma generation region, the second plasma being configured to emit ultraviolet radiation in the plasma generation region, exposing the substrate and the film deposited on the substrate to the ultraviolet radiation, wherein the ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate;

[0027] d) stopping generating the second plasma;

[0028] e) resuming generation of the first plasma in the plasma generation region until an interval thickness of the film deposited on the substrate reaches the threshold film thickness, wherein the interval thickness of the film corresponds to a thickness of the film deposited since generation of the second plasma was most recently stopped;

[0029] f) when the interval thickness of the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the first plasma and resuming the generation of the second plasma in the plasma generation region, and eliminating defects in the film on the substrate using the ultraviolet radiation from the second plasma;

[0030] g) Repeating operations d), e) and f) in a continuous manner until the film deposited on the substrate reaches a fixed film thickness.

[0031] 11. The method according to clause 10, further comprising:

[0032] After the film deposited on the substrate reaches the fixed film thickness, the generation of the first plasma in the plasma generation region is resumed until the film deposited on the substrate reaches a prescribed total film thickness.

[0033] 12. The method of clause 10, wherein the first plasma is generated using a process gas composition of argon and oxygen, and wherein the second plasma is generated using a process gas of helium.

[0034] 13. The method of clause 12, wherein the threshold film thickness is within a range extending up to approximately 75 Angstroms, and wherein the fixed film thickness is within a range greater than or equal to approximately 180 Angstroms.

[0035] 14. The method of clause 13, wherein the film deposited on the substrate is a silicon dioxide film.

[0036] 15. The method of clause 10, wherein defects within the film on the substrate include oxygen vacancies and / or trapped charges.

[0037] 16. The method of clause 10, wherein the stopping of generating the second plasma in operation d) is performed when the second plasma is continuously generated for a time period extending within a range from about 5 seconds to about 60 seconds.

[0038] 17. A method for ex-situ treatment of film surface defects during a plasma-based film deposition process, comprising:

[0039] a) positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber;

[0040] b) generating a plasma in the plasma generating region, the plasma being configured to cause a film to be deposited on the substrate, wherein the plasma is generated until the film deposited on the substrate reaches a threshold film thickness;

[0041] c) when the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the plasma, and moving the substrate to an ultraviolet radiation device configured to generate ultraviolet radiation, and exposing the substrate and the film deposited on the substrate to the ultraviolet radiation, wherein the ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate;

[0042] d) repositioning the substrate to be exposed to the plasma generation region within the plasma processing chamber;

[0043] e) resuming generation of the plasma in the plasma generation region until an interval thickness of a film deposited on the substrate reaches the threshold film thickness, wherein the interval thickness of the film corresponds to a thickness of the film deposited since the substrate was most recently exposed to ultraviolet radiation in the ultraviolet radiation device;

[0044] f) when the interval thickness of the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the plasma, moving the substrate to the ultraviolet radiation device, and exposing the substrate and the film deposited on the substrate to the ultraviolet radiation to eliminate defects in the film on the substrate;

[0045] g) Repeating operations d), e) and f) in a continuous manner until the film deposited on the substrate reaches a fixed film thickness.

[0046] 18. The method of clause 17, wherein each of operations c) and f) comprises generating a second plasma within the ultraviolet radiation device, wherein the second plasma is configured to emit ultraviolet radiation.

[0047] 19. The method of clause 17, wherein each of operations c) and f) comprises operating an electrically powered ultraviolet radiation source disposed within the ultraviolet radiation device.

[0048] 20. A method for in-situ treatment of film surface defects during a plasma-based film deposition process, comprising:

[0049] a) positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber;

[0050] b) generating a plasma in the plasma generating region, the plasma being configured to cause a film to be deposited on the substrate, wherein the plasma is generated until the film deposited on the substrate reaches a threshold film thickness;

[0051] c) when the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the plasma, and operating the ultraviolet radiation device exposed to the plasma generation region to transmit ultraviolet radiation through the plasma generation region to expose the substrate and the film deposited on the substrate to the ultraviolet radiation, wherein the ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate;

[0052] d) stopping the operation of the ultraviolet radiation device;

[0053] e) resuming generation of the ions in the plasma generation region until an interval thickness of the film deposited on the substrate reaches the threshold film thickness, wherein the interval thickness of the film corresponds to a thickness of the film deposited since the last cessation of operation of the ultraviolet radiation device;

[0054] f) when the interval thickness of the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the plasma and resuming operation of the ultraviolet radiation device exposed to the plasma generation region to transmit ultraviolet radiation through the plasma generation region to eliminate defects in the film on the substrate;

[0055] g) Repeating operations d), e) and f) in a continuous manner until the film deposited on the substrate reaches a fixed film thickness.

[0056] 21. An apparatus for in-situ treatment of film surface defects during a plasma-based film deposition process, comprising:

[0057] a substrate support having a top surface configured to support a substrate during a plasma processing operation to deposit a film on the substrate;

[0058] an electrode configured to deliver radio frequency power into a plasma generation region overlying the substrate support;

[0059] a process gas delivery component configured to deliver a process gas to the plasma generation region;

[0060] an exhaust outlet configured to exhaust gas from the plasma generation region; and

[0061] An ultraviolet radiation device is configured to transmit ultraviolet radiation through the plasma generation region in a direction toward the top surface of the substrate support.

[0062] 22. The apparatus of clause 21, further comprising: a control system configured to direct the generation of the plasma in the plasma generation region and to direct the operation of the ultraviolet radiation device such that the generation of the plasma in the plasma generation region and the transmission of ultraviolet radiation through the plasma generation region occur in a continuous manner without moving the substrate from the top surface of the substrate support.

[0063] Other aspects and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate the invention by way of example. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1A According to some embodiments of the present invention, a substrate processing system is shown.

[0065] Figure 1B

[0013] According to some embodiments of the present invention, a substrate processing system configured to perform an atomic layer deposition (ALD) process on a substrate is shown.

[0066] Figure 2A top view of a multi-station processing tool including four processing stations is shown according to some embodiments of the present invention.

[0067] Figure 3 A schematic diagram of an embodiment of a multi-station processing tool interfacing with inbound load locks and outbound load locks is shown in accordance with some embodiments of the present invention.

[0068] Figure 4 Examples of a susceptor configured to receive a substrate for a deposition process are shown according to some embodiments of the present invention.

[0069] Figure 5 A flow chart of a method for in-situ treatment of film surface defects during a plasma-based film deposition process is shown in accordance with some embodiments of the present invention.

[0070] Figure 6 A flow chart of a method for in-situ treatment of film surface defects during a plasma-based film deposition process is shown in accordance with some embodiments of the present invention.

[0071] Figure 7 A flow chart of a method for treating film surface defects ex situ during a plasma based film deposition process is shown according to some embodiments of the present invention.

[0072] Figure 8 A flow chart is shown of a method for in-situ treatment of film surface defects during a plasma-based film deposition process using an ultraviolet radiation device configured to irradiate a plasma generation region within a plasma processing chamber.

[0073] Fig. 9A According to some embodiments of the present invention, it is shown that the internal Figure 8 A substrate processing system for the method.

[0074] Fig. 9B According to some embodiments of the present invention, Fig. 9A A substrate processing system is operated to generate plasma in a plasma generation region overlying a substrate.

[0075] Fig. 9C According to some embodiments of the present invention, Fig. 9A A substrate processing system is provided that operates to generate ultraviolet radiation from an ultraviolet radiation device and transmit the ultraviolet radiation through a plasma generation region toward a substrate. DETAILED DESCRIPTION

[0076] In the following description, many specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be implemented without some or all of these specific details. In other cases, well-known processing operations are not described in detail to avoid unnecessarily obscuring the present invention.

[0077] The deposition of the film can be achieved in a plasma enhanced chemical vapor deposition (PECVD) system. The PECVD system can take many different forms. For example, the PECVD system includes one or more chambers or "reactors" (sometimes including multiple stations) that accommodate one or more substrates and are suitable for substrate processing. Each chamber can accommodate one or more substrates for processing. One or more chambers hold the substrate in one or more defined positions (with or without movement in the position, such as rotation, vibration or other agitation). During processing, the substrate being deposited can be transferred from one station to another in the reactor chamber. Of course, film deposition can occur entirely at a single station, or any part of the film can be deposited at any number of stations. During processing, each substrate is held in place by a susceptor, a substrate chuck and / or other substrate holding device. For certain operations, the device may include a heater (e.g., a hot plate) to heat the substrate.

[0078] In exemplary embodiments, the term substrate as used herein refers to a semiconductor wafer. In addition, in various embodiments, the substrates referred to herein may vary in form, shape, and / or size. For example, in some embodiments, the substrates referred to herein may correspond to a 200 mm (millimeter) semiconductor substrate, a 300 mm semiconductor substrate, or a 450 mm semiconductor substrate. In addition, in some embodiments, the substrates referred to herein may correspond to non-circular substrates (other shapes such as rectangular substrates for flat panel displays).

[0079] Figure 1A According to some embodiments of the present invention, a substrate processing system 100 is shown for processing a substrate 101. The system includes a chamber 102 having a lower chamber portion 102b and an upper chamber portion 102a. A central column 141 is configured to support a pedestal 140 formed of a conductive material. According to the settings of the RF direction control module 250, the conductive pedestal 140 is connected to receive an RF signal from an RF power source 104 through a matching network 106. In addition, in Figure 1AIn the substrate processing system 100 of the embodiment of the present invention, according to the setting of the RF direction control module 250, the showerhead electrode 150 is configured and connected to receive the RF signal from the RF power supply 104 through the matching network 106. In some embodiments, the RF direction control module 250 is configured to direct the RF signal transmitted from the RF power supply 104 via the matching network 106 to the showerhead electrode 150 or the pedestal 140. In addition, the RF direction control module 250 is configured to electrically connect any one of the showerhead electrode 150 and the pedestal 140 that is not currently receiving the RF signal to the reference ground potential. In this way, at a given time, the RF direction control module 250 operates to ensure that the showerhead electrode 150 will receive the RF signal from the RF power supply 104 when the pedestal 140 is electrically connected to the reference ground potential, or the pedestal 140 will receive the RF signal from the RF power supply 104 when the showerhead electrode 150 is electrically connected to the reference ground potential.

[0080] The RF power source 104 is controlled by a control module 110 (e.g., a controller). The control module 110 is configured to operate the substrate processing system 100 by executing process input and control instructions / programs 108. The process input and control instructions / programs 108 may include a process recipe having instructions for parameters such as power levels, timing parameters, process gases, mechanical movement of the substrate 101, for example, to deposit or form a film on the substrate 101.

[0081] In various embodiments, the RF power source 104 may include one or more RF power sources operating at one or more frequencies. Multiple RF frequencies may be provided to the showerhead electrode 150 or the pedestal 140 simultaneously based on the operation of the RF directional control module 250. In some embodiments, the frequency of the RF power signal is set within a range from 1kHz (kilohertz) to 100MHz (megahertz). In some embodiments, the frequency of the RF power signal is set within a range from 400kHz to 60MHz. In some embodiments, the RF power source 104 is configured to generate RF signals at frequencies of 2MHz, 27MHz, and 60MHz. In some embodiments, the RF power source 104 is configured to generate one or more high-frequency RF signals within a frequency range extending from about 1MHz to about 60MHz, and to generate one or more low-frequency RF signals within a frequency range extending from about 100kHz to about 1MHz. The RF power source 104 may include frequency-based filtering, i.e., high-pass filtering and / or low-pass filtering, to ensure that the specified RF signal frequency is transmitted. It should be understood that the above-mentioned RF frequency ranges are provided by example. In fact, the RF power supply 104 may be configured to generate substantially any RF signal having substantially any frequency as desired.

[0082] The matching network 106 is configured to match impedance so that the RF signal generated by the RF power supply 104 can be effectively transmitted to the plasma load within the chamber 102. Generally speaking, the matching network 106 is a network of capacitors and inductors that can be adjusted to tune the impedance encountered by the RF signal as it is transmitted to the plasma load within the chamber 102.

[0083] In some embodiments, the center column 141 can include lift pins controlled by a lift pin control 122. The lift pins are used to lift the substrate 101 from the pedestal 140 so that the end effector can pick up the substrate 101, and to lower the substrate 101 after being placed by the end effector. The substrate processing system 100 also includes a gas supply system 112 connected to a process gas supply source 114 (e.g., a gas chemical supply source from a facility). Depending on the process being performed, the control module 110 controls the delivery of the process gas 114 via the gas supply system 112. The selected process gas then flows into the showerhead electrode 150 and is distributed into a processing volume defined between the showerhead electrode 150 and the substrate 101 placed on the pedestal 140.

[0084] In addition, the process gas may or may not be premixed. Appropriate valves and mass flow control mechanisms may be employed within the gas supply system 112 to ensure that the appropriate process gas is delivered during the deposition and plasma processing phases of the process. The process gas exits the processing volume and flows through the exhaust outlet 143. A vacuum pump (e.g., a one-stage or two-stage mechanical dry pump, etc.) draws the process gas from the processing volume and maintains an appropriate low pressure in the processing volume through a closed-loop feedback controlled flow restriction device (e.g., a throttle valve or a swing valve).

[0085] Also shown is a carrier ring 200 surrounding an outer region of the susceptor 140. The carrier ring 200 is configured to support the substrate 101 during transport of the substrate 101 to and from the susceptor 140. The carrier ring 200 is configured to be located on a carrier ring support area, which is a step below the substrate support area in the center of the susceptor 140. The carrier ring 200 has an annular disk structure and includes an outer edge side (e.g., an outer radius) of its disk structure, and a substrate edge side (e.g., an inner radius) of its disk structure closest to where the substrate 101 is located. The substrate edge side of the carrier ring 200 includes a plurality of contact support structures configured to lift the substrate 101 when the carrier ring 200 is lifted by the spider fork 180. The carrier ring 200 is thus lifted together with the substrate 101 and can be rotated to another station in a multi-station system, for example. The carrier ring lifting and / or rotation control signal 124 is generated by the control module 110 to control the operation of the spider fork 180 to lift and / or rotate the carrier ring 200.

[0086] In some embodiments, an electrically insulating layer 507 is disposed on the top surface of the base 140, and a conductive layer 509 is disposed on the electrically insulating layer 507. The conductive layer 509 is configured to support the substrate 101. Moreover, in these embodiments, the conductive layer can be electrically connected to the positive pole of a direct current (DC) power source 521 through a low pass filter 525. The DC power source 521 is also connected to be controlled by the control module 110. Therefore, in some embodiments, current can be transmitted from the DC power source 521 through the low pass filter 525 to the conductive layer 509 according to a prescribed recipe provided by the process input and control instructions / program 108 and executed by the control module 110.

[0087] Figure 1B According to some embodiments of the present invention, a substrate processing system 100A is shown that is configured to perform an atomic layer deposition (ALD) process (e.g., an ALD oxide process) on a substrate 101. Figure 1B The figure shows the Figure 1A 102a, 102b, 102c, 102d, 102e ...

[0088] In some embodiments, a heating element 253 (e.g., a resistive heating element) is disposed with the dielectric body 251 of the susceptor 140A. The heating element 253 is connected to a heater power supply 255, which in turn is connected to the control module 110. In some embodiments, the heater power supply 255, when the heating element 253 is present, can operate according to a prescribed recipe, which is provided by the process input and control instructions / program 108 and executed by the control module 110. It should also be understood that a temperature measurement device can be mounted on / in the susceptor 140A and / or at other locations around the susceptor 140A to provide temperature measurement data to the control module 110, thereby enabling the operation of a closed-loop temperature feedback control circuit between the control module 110 and the heater power supply 255.

[0089] According to the configuration of the RF direction control module 250, the dielectric body 251 of the base 140A includes an RF electrode 254, which is configured and connected to receive an RF signal from the RF power source 104 through the matching network 106. Figure 1B In the substrate processing system 100A of FIG. 1 , according to the setting of the RF direction control module 250, the showerhead electrode 150A is configured and connected to receive the RF signal from the RF power supply 104 through the matching network 106. In some embodiments, the RF direction control module 250 is configured to guide the RF signal delivered from the RF power supply 104 via the matching network 106 to the showerhead electrode 150A or the RF electrode 254. In addition, the RF direction control module 250 is configured to electrically connect any one of the showerhead electrode 150A and the RF electrode 254 that is not currently receiving the RF signal to the reference ground potential. In this way, at a given time, the RF direction control module 250 operates to ensure that the showerhead electrode 150A will receive the RF signal from the RF power supply 104 while the RF electrode 254 is electrically connected to the reference ground potential, or the RF electrode 254 will receive the RF signal from the RF power supply 104 while the showerhead electrode 150A is electrically connected to the reference ground potential.

[0090] Figure 2 A top view of a multi-station processing tool 300 including four processing stations is shown according to some embodiments of the present invention. The top view is a view of the lower chamber portion 102b (e.g., the upper chamber portion 102a is removed for illustration). The four processing stations are accessed by a spider fork 180. Each spider fork 180 or fork includes a first arm and a second arm, each arm being positioned around a portion of each side of the base 140 / 140A. The spider fork 180 using the engagement and rotation mechanism 220 is configured to lift and raise the carrier ring 200 from the processing station (i.e., from the lower surface of the carrier ring 200) in a simultaneous manner, and then rotate at least one or more stations before lowering the carrier ring 200 (wherein at least one of the carrier rings supports a substrate 101) so that further plasma processing, treatment and / or film deposition can be performed on the corresponding substrate 101.

[0091] Figure 3 A schematic diagram of an embodiment of a multi-station processing tool 300 interfaced with an inbound load lock 302 and an outbound load lock 304 is shown according to some embodiments of the present invention. A robot 306 is configured to move a substrate 101 from a cassette loaded through a box 308 into the inbound load lock 302 via an atmospheric port 310 at atmospheric pressure. The inbound load lock 302 is coupled to a vacuum source / pump so that the inbound load lock 302 can be evacuated when the atmospheric port 310 is closed. The inbound load lock 302 also includes a chamber transfer port 316 that interfaces with the processing chamber 102. Therefore, when the chamber transfer port 316 is open, another robot 312 can move a substrate from the inbound load lock 302 to the pedestal 140 / 140A of the first processing station for processing.

[0092] The processing chamber 102 shown includes four processing stations, Figure 3The exemplary embodiments shown are numbered 1 through 4. In some embodiments, the processing chamber 102 can be configured to maintain a low pressure environment so that substrates can be transferred between processing stations 1-4 using the carry ring 200 without experiencing vacuum break and / or air exposure. Figure 3 Each process station 1-4 depicted in FIG. 1 includes a pedestal 140 / 140A and a showerhead electrode 150 / 150A and associated process gas supply connections. Furthermore, it should be understood that in other embodiments, the process chamber 102 may include fewer than four process stations or more than four process stations.

[0093] Figure 3 Also shown is a spider fork 180 for transferring substrates within the processing chamber 102. As described above, the spider fork 180 rotates and is capable of transferring substrates from one processing station to another. The transfer occurs by enabling the spider fork 180 to lift the carrier ring 200 from the outer lower surface, thereby lifting the substrate 101, and rotating the substrate 101 and the carrier ring 200 together to the next processing station. In one configuration, the spider fork 180 is made of a ceramic material to withstand high levels of heat during processing.

[0094] Figure 4 An example of a pedestal 140 / 140A configured to receive a substrate 101 for a deposition process such as an atomic layer deposition (ALD) process is shown in accordance with some embodiments of the present invention. The pedestal 140 / 140A includes a conductive layer 509 located on a central top surface of the pedestal 140 / 140A, wherein the central top surface is defined by a circular area extending from a central axis 420 of the pedestal 140 / 140A to a top surface diameter 422 defining an edge of the central top surface. The conductive layer 509 includes a plurality of substrate supports 404a, 404b, 404c, 404d, 404e, and 404f distributed throughout the conductive layer 509 and configured to support the substrate 101. The substrate support level is defined by the vertical position of the bottom surface of the substrate 101 when the substrate 101 is located on the substrate supports 404a, 404b, 404c, 404d, 404e, and 404f. Figure 4 In the example of FIG. 5 , six substrate supports 404a, 404b, 404c, 404d, 404e, and 404f are symmetrically distributed around the periphery of the conductive layer 509. However, in other embodiments, any number of substrate supports may be present on the conductive layer 509, and the substrate supports may be distributed on the conductive layer 509 in any suitable arrangement to support the substrate 101 during the deposition process operation. Figure 4Also shown are recesses 406a, 406b, and 406c configured to accommodate lift pins. The lift pins may be used to lift the substrate 101 from the substrate supports 404a, 404b, 404c, 404d, 404e, and 404f to allow engagement of the substrate 101 by an end effector.

[0095] In some embodiments, each substrate support 404a, 404b, 404c, 404d, 404e, and 404f defines a minimum contact area structure (MCA). MCAs are used to improve the precision fit between surfaces when high precision or tolerance is required and / or minimal physical contact is desired to reduce the risk of defects. Other surfaces in the system may also include MCAs, such as above the carrier ring 200 supports, and above the internal substrate support area of ​​the carrier ring 200.

[0096] The base 140 / 140A also includes an annular surface 410 that extends from a top surface diameter 422 of the base 140 / 140A to an outer diameter 424 of the annular surface 410. The annular surface 410 defines an annular region around the conductive layer 509, but at a step down from the conductive layer 509. That is, the vertical position of the annular surface 410 is lower than the vertical position of the conductive layer 509. A plurality of carry ring supports 412a, 412b, and 412c are positioned substantially at / along the edge (outer diameter) of the annular surface 410 and are symmetrically distributed around the annular surface 410. In some embodiments, the carry ring supports may define an MCA for supporting the carry ring 200. In some embodiments, the carry ring supports 412a, 412b, and 412c extend beyond the outer diameter 424 of the annular surface 410, while in other embodiments, the carry ring supports 412a, 412b, and 412c do not extend beyond the outer diameter 424 of the annular surface 410. In some embodiments, the top surfaces of the carry ring supports 412a, 412b, and 412c have a height slightly higher than the height of the annular surface 410, so that when the carry ring 200 rests on the carry ring supports 412a, 412b, and 412c, the carry ring 200 is supported at a predetermined distance above the annular surface 410. Each of the carry ring supports 412a, 412b, and 412c may include a recess (e.g., the recess 413 of the carry ring support 412a) in which an extension protruding from the underside of the carry ring 200 is seated when the carry ring 200 is supported by the carry ring supports 412a, 412b, and 412c. The engagement of the carry ring extensions with the recesses (413) in the carry ring supports 412a, 412b, and 412c provides secure positioning of the carry ring 200 and prevents movement of the carry ring 200 when seated on the carry ring supports 412a, 412b, and 412c.

[0097] In some embodiments, the top surfaces of the carry ring supports 412a, 412b, and 412c are flush with the annular surface 410. In other embodiments, there is no carry ring support defined separately from the annular surface 410, such that the carry ring 200 can be placed directly on the annular surface 410 and such that there is no gap between the carry ring 200 and the annular surface 410. In such embodiments, the path between the carry ring 200 and the annular surface 410 is closed, thereby preventing precursor material from reaching the backside / underside of the substrate 101 via this path.

[0098] exist Figure 4 In the exemplary embodiment of , there are three carry ring supports 412a, 412b, and 412c symmetrically positioned along the outer edge region of the annular surface 410. However, in other embodiments, there may be more than three carry ring supports distributed anywhere along the annular surface 410 of the base 140 / 140A to support the carry ring 200 in a stable resting configuration.

[0099] When substrate 101 is supported by substrate supports 404a, 404b, 404c, 404d, 404e, and 404f, and when carrier ring 200 is supported by carrier ring supports 412a, 412b, and 412c, an edge region of substrate 101 is disposed on an inner portion of carrier ring 200. Generally, the edge region of substrate 101 extends inwardly from an outer edge of substrate 101 by about 2 millimeters (mm) to about 5 mm. A vertical spacing is thereby defined between the edge region of substrate 101 and the inner portion of carrier ring 200. In some embodiments, the vertical spacing is about 0.001 inches to about 0.010 inches. Supporting carrier ring 200 at a predetermined distance above annular surface 410 and the vertical spacing between the edge region of substrate 101 and the inner portion of carrier ring 200 can be controlled to limit deposition on the backside / underside of substrate 101 in the edge region of substrate 101.

[0100] Some plasmas used to deposit thin films or treat substrate surfaces are unstable under conditions that are preferred from a process standpoint. For example, plasmas generated using argon-rich process gas compositions may be unstable under certain process conditions. However, from a process standpoint, it is preferred to use argon-rich plasmas. Argon-rich plasmas are capable of depositing very high quality films by ion bombardment, even at low temperatures (e.g., 50°C for patterning). In addition, compared with nitrogen-containing plasmas (e.g., N 2 or N 2 Unlike Ar / O, argon-rich plasmas do not adversely affect subsequent dry etch rates. For example, Ar / O plasmas operating in the 1 to 6 Torr pressure range and at high RF power (>200W / 300mm diameter substrate processing station)2 Capacitively coupled plasma (CCP) discharges show instabilities within the plasma. One such plasma instability, referred to herein as a "plasma mass," is characterized by a small area of ​​higher density (brighter) plasma surrounded by a larger volume of normal density plasma. When a plasma mass is formed, the deposited film is locally densified near the plasma mass due to the interaction of the film with the local high-density plasma corresponding to the plasma mass, which results in reduced film uniformity. The spatial distribution of the plasma mass on the substrate 101 can vary between processes and within a given process. In addition, the plasma mass can move on the substrate 101 during a given process. It should be understood that the plasma mass, for example, causes a reduction in process uniformity on the substrate 101 by changing the thickness of the deposited film at different locations on the substrate 101. The non-uniformity of the film thickness caused by the plasma mass can be about 1% to 2% of the total film thickness, which may be significant in some applications where an ultra-flat film profile is required. For example, a film deposited using ALD may require angstrom-level thickness control. For example, for a deposited film thickness of 300 angstroms, the film thickness should be controlled to have a thickness variation of less than 2 angstroms across the substrate.

[0101] During the example film deposition process, an operation is performed to apply a monolayer of precursor gas without applying any RF power. The precursor gas adheres to the substrate 101. In some embodiments, the precursor gas includes silicon to enable the formation of silicon oxide on the substrate. Then an operation is performed to flush the precursor gas from the processing volume above the substrate 101, thereby leaving a monolayer of precursor gas on the substrate 101. An oxidation process is then performed on the substrate 101. In the oxidation process, the process gas flows into the processing volume above the substrate 101, and RF power is applied to the process gas to generate a plasma within the processing volume. The plasma drives the oxidation reaction on the substrate 101. In some embodiments, the process gas will contain oxygen plus one or more other bombardment gases (such as argon, etc.), wherein the bombardment gas fully densifies the plasma. The bombardment gas is a gas that effectively densifies the deposited film. The bombardment gas that densifies the deposited film is those gases that can effectively transfer energy to the deposited film. In some embodiments, the bombardment gas is a monatomic inert gas, such as argon, etc., which does not chemically react with the deposited film and lacks vibrational or rotational molecular modes. For example, in an exemplary process, the process gas mixture may include about 5% to about 20% oxygen, with the remainder of the process gas mixture being argon. Also, in other exemplary processes, the percentage of oxygen to bombardment gas in the process gas mixture may be less than 5% or greater than 20%.

[0102] During the oxidation process, when a film of a specific thickness is formed on the substrate 101, plasma clusters may begin to appear on the substrate 101. The number and size of plasma clusters are directly correlated with the amount of bombardment process gas (e.g., argon) in the process gas mixture. Therefore, reducing the amount of bombardment process gas in the process gas mixture can be used to reduce the intensity of plasma clusters. However, a higher percentage of bombardment process gas is also usually necessary to provide enough plasma density to ensure proper film formation, and to improve film quality, such as better etching resistance, by bombardment of bombardment process gas ions (e.g., argon ions). In addition, a large amount of RF power is required to generate plasma, because if enough RF power is not applied, the plasma density will be insufficient. However, increasing the applied RF power leads to the formation of more plasma clusters. Some process applications use an applied RF power / 300mm diameter substrate processing station of about 300W. However, other process applications may require a higher RF power (e.g., 400W, or even higher) / 300mm diameter substrate processing station.

[0103] In view of the foregoing, a method of suppressing the formation of plasma clusters is to reduce the applied RF power and / or increase the oxygen concentration in the gas mixture. More specifically, lower process power (that is, lower applied RF power) or lower bombardment gas (usually argon) concentration in process gas (relative to oxygen) leads to lower plasma density, thereby suppressing the formation of plasma clusters. Unfortunately, from the perspective of deposited film quality, these conditions are not preferred. For example, when the ion bombardment from plasma is insufficient under lower process power or lower bombardment gas concentration in process gas, the film quality decreases. Therefore, by reducing process power and / or reducing bombardment gas concentration (such as argon concentration) in process gas, it may not always be possible to maintain the quality of deposited film while suppressing the formation of plasma clusters.

[0104] Plasma activated ALD silicon oxide (SiO 2 ) is used in a variety of memory and logic applications in the semiconductor device industry, such as multiple patterning, hard mask, electrical pad, through silicon via (TSV), etc. Some plasma activated ALD SiO 2 The process uses argon-rich O 2 / Ar plasma converts the Si precursor on the substrate into the desired SiO 2 Argon-rich plasmas can provide argon-rich plasmas to deposit very high quality films even at low temperatures (e.g., 50°C in patterning applications) by providing sufficient ion bombardment. In addition, the use of argon-rich plasmas is not detrimental to the subsequent dry etch rate of the deposited film, whereas the use of nitrogen-containing plasmas (e.g., N 2 or N 2O) does adversely affect the subsequent dry etch rate of the deposited film.

[0105] High density argon-rich plasmas are susceptible to instabilities such as plasmoids. Plasmoids are localized plasma instabilities that are visually observable and manifest as film thickness inconsistencies, which are usually characterized as localized reductions in film thickness across the substrate. As the film is deposited and thickness grows, plasmoids initially appear at a critical "threshold film thickness" and persist until the film reaches a "fixed film thickness". For example, in SiO 2 In the case of ALD of films, plasmons may begin to appear at a threshold film thickness of about 75 angstroms (occurs at about 50 ALD cycles) and persist to a fixed film thickness of about 180 angstroms (occurs at about 120 ALD cycles). Thus, a significant amount of ALD processing may occur in the presence of potentially destructive plasmons. It should be understood that the specific value between the threshold film thickness and the fixed film thickness that results in the occurrence of plasmons may vary based on process parameters and based on the precursor materials used to deposit the film.

[0106] Film thickness instability due to plasma instability causes local die / device failures, resulting in semiconductor device production waste. The film deposition process window in which plasma instabilities such as plasma clusters can be avoided is significantly reduced, especially in terms of the parameters of applied power and plasma exposure time. For example, plasma cluster characteristics begin to appear at a power level of about 300 watts per processing station. Due to the corresponding higher plasma density, high power is significantly related to the formation of plasma clusters. In order to avoid the formation of plasma clusters, the limitation of power greatly narrows the available process window for film deposition and reduces the scalability of current film deposition processes to future technology nodes, in which higher power will be required to achieve acceptable film quality. In addition, simply changing the plasma process gas from an argon-rich composition to an argon-rich composition will reduce the film quality. 2 / N 2 or 2 / N 2 O compositions are not a viable option for mitigating plasmoid formation due to the improved ion bombardment of the substrate provided by the Ar-rich plasma and due to the adverse effect on the subsequent dry etch rate of the film when N is present in the film. Therefore, it is of interest to prevent / suppress / mitigate plasma instabilities during film deposition processes (e.g., ALD and / or PECVD) while maintaining the use of Ar-rich plasma process gases.

[0107] Plasmoids are maintained by secondary electron emission of the growing film thickness (i.e., the growing dielectric oxide surface). Secondary electron emission is increased by trapped charge defects and / or oxygen vacancies in the deposited film. Oxygen vacancies can appear as positively charged defects in the deposited film. Therefore, it is of interest to passivate / neutralize / correct trapped charge defects and / or oxygen vacancies in the deposited film in order to reduce secondary electron emission of the film, thereby reducing the formation of plasmoids.

[0108] Disclosed herein are systems and methods for preventing / suppressing / mitigating plasma instabilities, such as plasmoids, during ALD and PECVD processes by treating a film deposited on a substrate surface and / or exposing the film to ultraviolet (UV) radiation. UV radiation causes reactions that passivate / neutralize / correct trapped charge defects and / or oxygen vacancies within the deposited film to reduce secondary electron emission from the film, thereby reducing the formation of plasmoids. For example, UV radiation with tailored energy can generate high-energy electrons from the bulk material below the deposited film, and these high-energy electrons can migrate to the surface of the film and passivate oxygen vacancies that are hole-type defects. In addition, UV radiation can induce secondary film correction effects, such as eliminating silanol (Si-OH), to provide a more robust Si-O-Si feedback bonding (backbonding) of the film. UV-induced effects can reduce trapped charge density in the deposited film. The systems and methods disclosed herein for UV treatment of deposited films are particularly useful in SiO on substrates. 2 In the ALD process of the film.

[0109] UV is a spectral class of electromagnetic radiation having wavelengths (λ) in the range extending from 100 nanometers (nm) to 400 nm. The UV spectrum can be divided into several spectral subclasses, including vacuum ultraviolet (VUV) (10 nm ≤ λ < 200 nm), extreme ultraviolet (EUV) (10 nm ≤ λ < 121 nm), hydrogen Lyman-α (H Lyman-α) (121 nm ≤ λ < 122 nm), far ultraviolet (FUV) (122 nm ≤ λ < 200 nm), ultraviolet C (UVC) (100 nm ≤ λ < 280 nm), mid-ultraviolet (MUV) (200 nm ≤ λ < 300 nm), ultraviolet B (UVB) (280 nm ≤ λ < 315 nm), near ultraviolet (NUV) (300 nm ≤ λ < 400 nm), and ultraviolet A (UVA) (315 nm ≤ λ < 400 nm). For ease of description, the term "ultraviolet radiation" as used herein refers to electromagnetic radiation characterized by any one or more spectral subclasses of the ultraviolet spectrum.

[0110] In some embodiments, a film deposited by ALD and / or PECVD is exposed to UV radiation as a pre-treatment of the film and / or as part of smart-treatment of the film during the ALD and / or PECVD process to passivate / correct surface defects in the film and / or reduce trapped charge density within the film, which in turn prevents / inhibits / mitigates the formation of plasma instabilities (e.g., plasmoids) during the duration of the ALD and / or PECVD process to complete the formation of the film. Smart-treatment of the film refers to exposing the film to UV radiation in an in-situ manner and in a desired manner to passivate / correct surface defects in the film as it is deposited to achieve its overall final thickness. In some embodiments, for example, the film can be exposed to UV radiation in-situ by generating / providing UV radiation within the ALD and / or PECVD processing environment, such as by generating a He plasma that emits UV radiation, or by operating a UV radiation source installed in the ALD and / or PECVD processing environment. Furthermore, in some embodiments, the film can be exposed to UV radiation ex situ by placing the substrate with the partially deposited film thereon within a separate apparatus configured to expose the substrate to the desired amount of UV radiation.

[0111] The systems and methods disclosed herein for using UV radiation to passivate / neutralize / correct film surface defects during ALD and / or PECVD processes to prevent / suppress / mitigate plasma instabilities (e.g., plasmons) are used to extend the effective ALD and / or PECVD process window in terms of process gas composition, process gas flow rate, pressure, and / or applied RF power. It should be understood that the term "surface" with respect to "surface defects" can be an extension to the "bulk" of the substrate and / or several molecular layers of material present on the surface of the substrate. In addition, the term "surface" can refer to the top thickness of the material on the substrate, as defined by the mean free path of electron emission. It should be understood that the systems and methods disclosed herein can be used with the following processes: deposition of substantially any type of dielectric film, including deposition of oxides (M x O y ) and nitride (M x N y )), where plasma instabilities may be caused by film surface defects, oxygen vacancies, and / or trapped charge defects, and can be used with any type of deposition process (e.g., ALD and PECVD, etc.). In addition, it should be understood that the systems and methods disclosed herein can use many different techniques to generate the required UV radiation, and the required UV radiation can be applied in situ or ex situ relative to the film deposition process.

[0112] In some embodiments, UV radiation used to eliminate (e.g., passivate / neutralize / correct) surface defects of a film is generated in situ by creating a He plasma exposed to a substrate during ALD and / or PECVD processing of the substrate. For example, in some embodiments, when a film is deposited on a substrate, the film is exposed to a He plasma exposed to a substrate during ALD and / or PECVD processing of the substrate. 2 The generation of plasma produces He plasma together. He plasma emits high-energy UV radiation, which is incident on the surface of the film on the substrate. When the UV radiation is incident on the substrate, the energy of the UV radiation is applied in a photo-initiation process to cause a reaction in the substrate, thereby being used to eliminate surface defects of the film on the substrate.

[0113] Figure 5 A flow chart of a method for in-situ treatment of surface defects of a film during a plasma-based film deposition process is shown according to some embodiments of the present invention. For example, Figure 5 The method can be used to perform a plasma-based film deposition process using substantially any type of plasma processing system equipped, such as the plasma processing system described in Figure 1A , Figure 1B , Figure 2 , Figure 3 and Figure 4 The method includes an operation 501 for positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber. The method also includes an operation 503 for generating a first plasma within the plasma generation region. The first plasma is configured to deposit a film on the substrate. In some embodiments, the first plasma is generated using a process gas composition of argon and oxygen. However, it should be understood that in other embodiments, a process gas or process gas mixture other than argon and oxygen may be used to generate the first plasma, as long as the first plasma is configured to deposit a desired film on the substrate in an acceptable manner. In some embodiments, the film deposited on the substrate is a silicon dioxide film. However, it should be understood that in other embodiments, the first plasma configured to deposit a film of substantially any type of material may be used to perform Figure 5 method.

[0114] The method also includes an operation 505 for generating a second plasma within the plasma generation region. The second plasma is configured to emit UV radiation within the plasma generation region, exposing the substrate to the UV radiation. The UV radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate. In some embodiments, the first plasma and the second plasma are simultaneously generated within the plasma generation region. In some embodiments, defects in the film deposited on the substrate may include oxygen vacancies and / or trapped charges and / or other anomalies in the film, which may cause plasma instability during further plasma-based deposition of the film on the substrate. In some embodiments, the reaction on the substrate caused by the UV radiation eliminates defects in the film on the substrate by one or more processes of passivation and charge neutralization.

[0115] In some embodiments, the second plasma is generated using a process gas composition of helium. However, it should be understood that in other embodiments, a process gas or process gas mixture other than helium may be used to generate the second plasma, as long as the second plasma generates sufficient UV radiation to eliminate defects in the deposited film, and as long as the second plasma does not adversely affect the deposited film and does not adversely affect subsequent processing of the deposited film.

[0116] In some embodiments, a second plasma is generated in the plasma generation region after the film deposited on the substrate reaches a threshold film thickness. As previously described, the threshold film thickness corresponds to the thickness of the deposited film at which plasma instability begins to occur due to defects in the deposited film that can promote the emission of secondary electrons (e.g., oxygen vacancies and / or trapped charges and / or other anomalies in the film) when the substrate is bombarded by energetic ions from the plasma. These ejected secondary electrons can be accelerated to high energies when they are pulled into the bulk plasma through the plasma sheath. And these accelerated electrons can form regions of high-density, unstable plasma, such as plasma clusters. This behavior is observed in argon-rich gas mixtures when the discharge interacts with a specific surface (e.g., a film of a specific composition and thickness). In some embodiments, the threshold film thickness is in a range extending up to about 75 angstroms.

[0117] In some embodiments, the UV emitting second plasma is continuously generated in the plasma generation region while the thickness of the film deposited on the substrate grows from a threshold film thickness to a fixed film thickness. The fixed film thickness corresponds to the thickness of the deposited film at which plasma instability due to defects in the deposited film no longer occurs. In some embodiments, the fixed film thickness is in a range of greater than or equal to about 180 angstroms.

[0118] In some embodiments, defects within a film deposited on a substrate are eliminated by applying UV radiation to the film in a flexible processing manner. For example, in some embodiments, defects within the film are treated in an in-situ manner by generating a helium plasma that is exposed to the substrate such that UV radiation emitted from the helium plasma will be incident on the film before the film reaches an undetermined thickness of the film (equal to a threshold film thickness), where the undetermined thickness of the film corresponds to the thickness of the film deposited since the defects within the film were most recently eliminated by exposing the film to UV radiation. Exposing the deposited film to ultraviolet radiation in a flexible processing manner can be performed multiple times during deposition of the film to reach a specified total thickness of the film on the substrate.

[0119] Figure 6 A flow chart of a method for in-situ treatment of surface defects of a film during a plasma-based film deposition process is shown according to some embodiments of the present invention. For example, Figure 6 The method may be performed using substantially any type of plasma processing system equipped to perform a plasma-based film deposition process, such as with reference to Figure 1A , Figure 1B , Figure 2 , Figure 3 and Figure 4 The method includes an operation 601 for positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber. The method also includes an operation 603 for generating a first plasma within the plasma generation region. The first plasma is configured to deposit a film on the substrate. In some embodiments, the first plasma is generated using a process gas composition of argon and oxygen. However, it should be understood that in other embodiments, a process gas or process gas mixture other than argon and oxygen may be used to generate the first plasma, as long as the first plasma is configured to deposit a desired film on the substrate in an acceptable manner. In some embodiments, the film deposited on the substrate is a silicon dioxide film. However, it should be understood that in other embodiments, the first plasma configured to deposit a film of substantially any type of material may be used to perform Figure 6 method.

[0120] A first plasma is generated in operation 603 until the film deposited on the substrate reaches a threshold film thickness. As previously described, the threshold film thickness corresponds to the thickness of the deposited film at which plasma instabilities begin to occur due to defects within the deposited film (e.g., oxygen vacancies and / or trapped charges and / or other anomalies within the film). In some embodiments, the threshold film thickness is within a range extending up to about 75 angstroms.

[0121] When the film deposited on the substrate reaches a threshold film thickness, the method proceeds to operation 605, where the generation of the first plasma is stopped and a second plasma is generated in the plasma generation region. The second plasma is configured to emit UV radiation in the plasma generation region, exposing the substrate and the film deposited on the substrate to the UV radiation, wherein the UV radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate. In some embodiments, the second plasma is generated using a process gas composition of helium. However, it should be understood that in other embodiments, a process gas or process gas mixture other than helium can be used to generate the second plasma, as long as the second plasma generates sufficient UV radiation to eliminate defects in the deposited film, and as long as the second plasma does not adversely affect the deposited film and does not adversely affect subsequent processing of the deposited film.

[0122] The method also includes an operation 607 for stopping the generation of the second plasma. In some embodiments, the stopping of the generation of the second plasma in operation 607 occurs when the second plasma has been continuously generated for a duration extending in the range of about 5 seconds to about 60 seconds. However, in other embodiments, the generation of the second plasma may be stopped when the second plasma has been continuously generated for less than 5 seconds or for more than 60 seconds. The method also includes an operation 609 for resuming the generation of the first plasma in the plasma generation region until the interval thickness of the film deposited on the substrate reaches a threshold film thickness. The interval thickness of the film corresponds to the thickness of the film deposited since the generation of the second plasma was last stopped. In other words, the interval thickness of the film corresponds to the thickness of the film deposited since defects in the film were last eliminated by exposing the film to UV radiation.

[0123] When the interval thickness of the film deposited on the substrate reaches the threshold film thickness, the method proceeds to operation 611, in which the generation of the first plasma is stopped and the generation of the second plasma in the plasma generation region is resumed. In operation 611, UV radiation from the second plasma is used again to eliminate defects in the film on the substrate. The method also includes operation 613, in which operations 607, 609 and 611 are repeated in a continuous manner until the film deposited on the substrate reaches a fixed film thickness. The fixed film thickness corresponds to the thickness of the deposited film when the instability of the plasma due to defects in the deposited film no longer occurs. In some embodiments, the fixed film thickness is within a range of greater than or equal to about 180 angstroms. The method may also include an operation of resuming the generation of the first plasma in the plasma generation region after the film deposited on the substrate reaches the fixed film thickness until the film deposited on the substrate reaches the specified total thickness of the film.

[0124] In some embodiments, a film deposited on a substrate can be exposed to UV radiation in an ex-situ manner to eliminate defects within the film. In such embodiments, the substrate is transferred from a plasma treatment system to a separate UV radiation device, the film is deposited in the plasma treatment system, and the film is exposed to UV radiation in the separate UV radiation device. In some embodiments, the substrate can be transferred back and forth between the plasma treatment system and the UV radiation device multiple times when a specified total thickness of the film is deposited on the substrate.

[0125] Figure 7 According to some embodiments of the present invention, a flow chart of a method for ex situ treatment of surface defects of a film during a plasma-based film deposition process is shown. The method includes an operation 701 for positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber. For example, Figure 7 The method may be performed using substantially any type of plasma processing system equipped to perform a plasma-based film deposition process, such as with reference to Figure 1A , Figure 1B , Figure 2 , Figure 3 and Figure 4 The method further includes an operation 703 for generating a plasma in the plasma generating region. The plasma is configured to deposit a film on the substrate.

[0126] In some embodiments, the plasma is generated using a process gas composition of argon and oxygen. However, it should be understood that in other embodiments, the plasma may be generated using process gases or process gas mixtures other than argon and oxygen, so long as the plasma is configured to deposit the desired film on the substrate in an acceptable manner. In some embodiments, the film deposited on the substrate is a silicon dioxide film. However, it should be understood that in other embodiments, the first plasma configured to deposit a film of substantially any type of material may be used to perform Figure 7 method.

[0127] In operation 703, a first plasma is generated until the film deposited on the substrate reaches a threshold film thickness. As previously described, the threshold film thickness corresponds to the thickness of the deposited film at which plasma instabilities begin to occur due to defects within the deposited film that can promote the ejection of secondary electrons from the film material (e.g., oxygen vacancies and / or trapped charges and / or other anomalies within the film) when the film is bombarded by energetic ions from the plasma. In some embodiments, the threshold film thickness is within a range extending up to about 75 angstroms.

[0128] When the film deposited on the substrate reaches a threshold film thickness, the method proceeds to 705, where generation of the plasma is stopped and the substrate is moved to a UV radiation device configured to generate UV radiation. In some embodiments, the UV radiation device is configured to be separate from a plasma processing chamber in which a plasma-based film deposition process is performed. Operation 705 also includes exposing the substrate and the film deposited on the substrate to UV radiation, wherein the UV radiation incident on the substrate causes a reaction on the substrate to eliminate defects within the film on the substrate. In some embodiments, defects within the film deposited on the substrate may include oxygen vacancies and / or trapped charges and / or other anomalies within the film, which may cause plasma instabilities during further plasma-based deposition of the film on the substrate. In some embodiments, the reaction on the substrate caused by the UV radiation eliminates defects within the film on the substrate by one or more processes of passivation and charge neutralization.

[0129] The method continues to operation 707 for repositioning the substrate to be exposed to the plasma generation region within the plasma processing chamber. The method also includes operation 709 for resuming the generation of plasma within the plasma generation region until an interval thickness of a film deposited on the substrate reaches a threshold film thickness, wherein the interval thickness of the film corresponds to the thickness of the film deposited since the substrate was most recently exposed to UV radiation within the UV radiation device. In other words, the interval thickness of the film corresponds to the thickness of the film deposited since defects within the film were most recently eliminated by exposing the film to UV radiation.

[0130] When the interval thickness of the film deposited on the substrate reaches the threshold film thickness, the method proceeds to operation 711, at which the generation of the plasma is again stopped and the substrate is again moved to the UV radiation device. Operation 711 also includes exposing the substrate and the film deposited on the substrate to UV radiation to again eliminate defects in the film on the substrate. The method also includes operation 713, at which operations 707, 709, and 711 are repeated in a continuous manner until the film deposited on the substrate reaches a fixed film thickness. The fixed film thickness corresponds to the thickness of the deposited film when instability of the plasma due to defects in the deposited film no longer occurs. In some embodiments, the fixed film thickness is in a range of greater than or equal to about 180 angstroms.

[0131] In some embodiments, the ultraviolet radiation device used in operations 705 and 711 is configured to generate a second plasma exposed to the substrate, wherein the second plasma is configured to emit a sufficient amount of UV radiation to eliminate defects present in a film deposited on the substrate. In some of these embodiments, the second plasma is generated using a process gas composition of helium. However, it should be understood that in other embodiments, a process gas or process gas mixture other than helium can be used to generate the second plasma, as long as the second plasma generates sufficient UV radiation to eliminate defects in the deposited film, and as long as the second plasma does not adversely affect the deposited film and does not adversely affect subsequent processing of the deposited film.

[0132] In addition, in some embodiments, an electrically driven UV radiation source is disposed within the UV radiation device in operations 705 and 711. In these embodiments, the electrically driven UV radiation source is configured to emit a sufficient amount of UV radiation to eliminate defects present in the film deposited on the substrate. For example, in some embodiments, the UV radiation source is an electrically driven lamp configured to emit photons in the UV spectrum. In addition, in some embodiments, the UV radiation device may include an arrangement of lenses and / or optical fibers to distribute and transmit UV radiation from the UV radiation source to the film deposited on the substrate.

[0133] In some embodiments, defects within a film deposited on a substrate can be eliminated by exposing the film to UV radiation in an in-situ manner using a UV radiation device configured to expose the plasma generation region within a plasma processing chamber. Figure 8 According to some embodiments of the present invention, a flow chart of a method for in-situ treatment of surface defects of a film using a UV radiation device configured to be exposed to a plasma generation region within a plasma processing chamber during a plasma-based film deposition process is shown. The method includes an operation 801 for positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber. The method includes an operation 803 for generating a plasma within the plasma generation region, wherein the plasma is configured to deposit a film on the substrate. In operation 803, the plasma is generated until the film deposited on the substrate reaches a threshold film thickness. In some embodiments, the plasma is generated using a process gas composition of argon and oxygen. However, it should be understood that in other embodiments, the plasma can be generated using a process gas or process gas mixture other than argon and oxygen, as long as the plasma is configured to deposit the desired film on the substrate in an acceptable manner. In addition, in some embodiments, the film deposited on the substrate is a silicon dioxide film. However, it should be understood that in other embodiments, the plasma can be performed using a plasma configured to deposit a film of substantially any type of material. Figure 8 method.

[0134] As previously described, the threshold film thickness corresponds to the thickness of the deposited film at which plasma instabilities begin to occur due to defects within the deposited film that can facilitate ejection of secondary electrons from the film material (e.g., oxygen vacancies and / or trapped charges and / or other anomalies within the film) when the film is bombarded by energetic ions from the plasma. In some embodiments, the threshold film thickness is within a range extending up to about 75 angstroms.

[0135] When the film deposited on the substrate reaches a threshold film thickness, the method proceeds to operation 805, where the generation of the plasma is stopped, and a UV radiation device exposed to the plasma generation region is operated to transmit UV radiation through the plasma generation region, exposing the substrate and the film deposited on the substrate to the UV radiation, wherein the UV radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate. In some embodiments, the defects in the film deposited on the substrate may include oxygen vacancies and / or trapped charges and / or other anomalies in the film, which may cause plasma instability during further plasma-based deposition of the film on the substrate. In some embodiments, the reaction on the substrate caused by the UV radiation eliminates the defects in the film on the substrate through one or more processes of passivation and charge neutralization.

[0136] In some embodiments, the UV radiation device includes an electrically driven UV radiation source. In these embodiments, the electrically driven UV radiation source is configured to emit a sufficient amount of UV radiation to eliminate defects present in a film deposited on a substrate. For example, in some embodiments, the UV radiation source is an electrically driven lamp configured to emit photons in the UV spectrum. In addition, in some embodiments, the UV radiation device may include an arrangement of lenses and / or optical fibers to distribute and transmit UV radiation from the UV radiation source to the film deposited on the substrate. In addition, it should be understood that in different embodiments, the UV radiation device and its operation may have variations in photon energy and / or lamp configuration and / or environmental conditions.

[0137] The method further includes an operation 807 for stopping the operation of the UV radiation device after the defects in the film have been sufficiently eliminated. The method continues to an operation 809 for resuming the generation of plasma in the plasma generation region until the interval thickness of the film deposited on the substrate reaches a threshold film thickness, wherein the interval thickness of the film corresponds to the thickness of the film deposited since the operation of the UV radiation device was last stopped. In other words, the interval thickness of the film corresponds to the thickness of the film deposited since the defects in the film were last eliminated by exposing the film to UV radiation.

[0138] When the interval thickness of the film deposited on the substrate reaches the threshold film thickness, the method proceeds to operation 811, at which the generation of the plasma is stopped and the operation of the UV radiation device exposed to the plasma generation region is resumed to transmit UV radiation through the plasma generation region to eliminate defects in the film on the substrate. The method also includes operation 813, at which operations 807, 809 and 811 are repeated in a continuous manner until the film deposited on the substrate reaches a fixed film thickness. The fixed film thickness corresponds to the thickness of the deposited film when instability of the plasma due to defects in the deposited film no longer occurs. In some embodiments, the fixed film thickness is in a range of greater than or equal to about 180 angstroms.

[0139] Fig. 9A According to some embodiments of the present invention, it is shown that the Figure 8 The substrate processing system 100C is a substrate processing system 100C. Figure 1B The substrate processing system 100C is a variation of the substrate processing system 100A. The substrate processing system 100C is an example of an apparatus for in-situ processing of film surface defects during a plasma-based film deposition process. The substrate processing system 100C includes a substrate support, such as a susceptor 140A, having a top surface configured to support a substrate 101 during a plasma processing operation to deposit a film on the substrate 101. The substrate processing system 100C also includes an electrode, such as a showerhead electrode 150A and / or an RF electrode 254, which is configured to transmit radio frequency power to a plasma generation region covering the substrate support. The substrate processing system 100C also includes a process gas delivery component, namely, a showerhead electrode 150A, which is configured to deliver a process gas to the plasma generation region. The substrate processing system 100C also includes an exhaust outlet 143 configured to exhaust gas from the plasma generation region.

[0140] In addition, the substrate processing system 100C includes a UV radiation device 901 configured to transmit UV radiation through the plasma generation region in a direction toward the top surface of the substrate support. In addition, in the substrate processing system 100C, the control module 110 serves as a control system configured to direct the generation of plasma in the plasma generation region and direct the direct operation of the UV radiation device 901 so that the generation of plasma in the plasma generation region and the transmission of UV radiation through the plasma generation region are performed in a continuous manner without moving the substrate 101 from the top surface of the substrate support. In some embodiments, the control signal is transmitted from the control module 110 to the UV radiation device 901 through the signal conductor 903. In some embodiments, the control module 100 is configured to operate the substrate processing system 100C by executing process input and control instructions / programs 108, which are defined as directing the generation of plasma in the plasma generation region and the transmission of UV radiation through the plasma generation region in a continuous manner without moving the substrate 101 from the top surface of the substrate support.

[0141] Fig. 9B According to some embodiments of the present invention, Figure 8 Operations 803 and 809 of the method are performed to generate plasma 905 in a plasma generation region covering the substrate 101. Fig. 9A A substrate processing system 100C is provided. Fig. 9C According to some embodiments of the present invention, Fig. 9A The substrate processing system 100C is based on Figure 8 Operations 805 and 811 of the method of the present invention are operated to generate UV radiation from the UV radiation device 901 and transmit the UV radiation through the plasma generation region toward the substrate 101, as represented by the set of arrows 907. It should be understood that the UV radiation device 901 can include an arrangement of lenses and / or optical fibers to distribute and transmit the UV radiation to the film deposited on the substrate 101. In addition, it should be understood that in different embodiments, the UV radiation device 901 and its operation can have variations in photon energy and / or lamp configuration and / or environmental conditions. It should be understood that the systems and methods disclosed herein for suppressing plasma instabilities to eliminate defects in deposited films by using UV radiation add minimal disturbances to the plasma processing system.

[0142] The systems and methods disclosed herein provide innovative UV radiation post-treatment of conformal dielectric films to passivate / neutralize / correct oxygen vacancies and / or trapped charges within the deposited film, thereby reducing secondary electron emission from the deposited film and correspondingly reducing the formation of plasma instabilities (e.g., plasmoids). The systems and methods disclosed herein also enable the film deposition process window to be extended to higher power states while maintaining the use of argon-rich plasmas and their associated beneficial argon ion bombardment, thereby providing high-quality film deposition for future technology nodes.

[0143] The foregoing description of the embodiments is provided for the purpose of illustration and description. The present invention is not intended to be exhaustive, nor is it intended to limit the present invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable where applicable, and can be used in a selected embodiment, even if not specifically shown or described. It may also be different in many respects. These changes should not be considered as departing from the present invention, and all such modifications are intended to be included within the scope of the present invention.

[0144] Although the foregoing invention has been described in some detail for the purpose of clear understanding, it is obvious that certain changes and modifications may be implemented within the scope of the appended claims. Therefore, the embodiments of the present invention should be considered illustrative rather than restrictive, and the present invention is not limited to the details given herein, but can be modified within the scope and equivalent scheme of the described embodiments.

Claims

1. An apparatus for in-situ treatment of film surface defects during a plasma-based film deposition process, wherein include: a substrate support having a top surface configured to support a substrate during a plasma processing operation to deposit a film on the substrate; an electrode configured to deliver radio frequency power into a plasma generation region overlying the substrate support; a process gas delivery component configured to deliver a process gas to the plasma generation region; an exhaust outlet configured to exhaust gas from the plasma generation region; and an ultraviolet radiation device configured to transmit ultraviolet radiation through the plasma generation region in a direction toward a top surface of the substrate support; a control system configured to direct generation of the plasma within the plasma generation region and to direct operation of the ultraviolet radiation device such that generation of the plasma within the plasma generation region and transmission of ultraviolet radiation through the plasma generation region occur in a continuous manner without moving the substrate from the top surface of the substrate support, wherein the control system is configured to direct generation of the plasma in the plasma generation region until the film deposited on the substrate reaches a threshold film thickness, wherein the control system is configured to direct the performance of a film defect elimination operation when the film reaches the threshold film thickness, the film defect elimination operation comprising operating the ultraviolet radiation device to transmit ultraviolet radiation to the film on the substrate so that the ultraviolet radiation causes a reaction on the substrate to eliminate defects within the film on the substrate, wherein the control system is configured to direct further generation of the plasma in the plasma generation region after completion of the film defect elimination operation until an interval thickness of the film deposited on the substrate reaches the threshold film thickness, the interval thickness of the film corresponding to the thickness of the film deposited since the film defect elimination operation was most recently completed, wherein the control system is configured to direct the repetition of the film defect elimination operation and the further generation of the plasma in the plasma generation region in a continuous manner until the film deposited on the substrate reaches a fixed film thickness.

2. The device according to claim 1, in, The ultraviolet radiation device is located above the substrate support.

3. The device according to claim 2, in, The ultraviolet radiation device is configured to extend over an entire top surface of the substrate support supporting the substrate during the plasma processing operation.

4. The device according to claim 1, in, The ultraviolet radiation device is electrically driven.

5. The device according to claim 1, in, The ultraviolet radiation device comprises an arrangement of lenses.

6. The device according to claim 1, in, The ultraviolet radiation device comprises an arrangement of optical fibers.

7. The device according to claim 6, in, The optical fiber is configured and connected to transmit ultraviolet radiation from an ultraviolet radiation source toward the top surface of the substrate support, and wherein the optical fiber is positioned to distribute the ultraviolet radiation over the top surface of the substrate support.

8. The device according to claim 1, in, The ultraviolet radiation device is configured to direct ultraviolet radiation in a direction substantially perpendicular to the top surface of the substrate support.

9. The device according to claim 1, in, The electrode and the process gas delivery components are integrated into a showerhead electrode.

10. The device according to claim 9, in, The ultraviolet radiation device is integrated into the showerhead electrode.

11. The device according to claim 9, in, The ultraviolet radiation device is attached to a lower surface of the showerhead electrode facing the top surface of the substrate support.

12. A method for ex-situ treatment of film surface defects during a plasma-based film deposition process, wherein include: a) positioning a substrate to be exposed to a plasma generation region within a plasma processing chamber; b) generating a plasma in the plasma generating region, the plasma being configured to cause a film to be deposited on the substrate, wherein the plasma is generated until the film deposited on the substrate reaches a threshold film thickness; c) when the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the plasma, and moving the substrate to an ultraviolet radiation device configured to generate ultraviolet radiation, and exposing the substrate and the film deposited on the substrate to the ultraviolet radiation, wherein the ultraviolet radiation incident on the substrate causes a reaction on the substrate to eliminate defects in the film on the substrate; d) repositioning the substrate to be exposed to the plasma generation region within the plasma processing chamber; e) resuming generation of the plasma in the plasma generation region until an interval thickness of the film deposited on the substrate reaches the threshold film thickness, wherein the interval thickness of the film corresponds to a thickness of the film deposited since the substrate was most recently exposed to ultraviolet radiation in the ultraviolet radiation device; f) when the interval thickness of the film deposited on the substrate reaches the threshold film thickness, stopping the generation of the plasma, moving the substrate to the ultraviolet radiation device, and exposing the substrate and the film deposited on the substrate to the ultraviolet radiation to induce the reaction on the substrate to eliminate defects in the film on the substrate; and g) Repeating operations d), e) and f) in a continuous manner until the film deposited on the substrate reaches a fixed film thickness.

13. The method according to claim 12, in, Each of operations c) and f) includes generating a second plasma within the ultraviolet radiation device, wherein the second plasma is configured to emit ultraviolet radiation.

14. The method of claim 13, wherein the plasma generated in the plasma generating region is a first plasma, wherein the first plasma is generated using a process gas composition of argon and oxygen, and wherein the second plasma is generated using a process gas of helium.

15. The method of claim 12, further comprising: include: The generation of the plasma in the plasma generation region is resumed after the film deposited on the substrate reaches the fixed film thickness until the film deposited on the substrate reaches a prescribed total film thickness.

16. The method according to claim 12, in, Each of operations c) and f) includes operating an electrically driven ultraviolet radiation source disposed within the ultraviolet radiation device.

17. The method according to claim 12, in, The threshold film thickness corresponds to the thickness of the deposited film at which plasma instabilities begin to occur due to defects within the deposited film.

18. The method according to claim 17, in, The defects within the deposited film include oxygen vacancies and / or trapped charges that facilitate ejection of secondary electrons from the deposited film when the deposited film is bombarded by energetic ions from the plasma.

19. The method according to claim 12, in, The fixed film thickness corresponds to the thickness of the deposited film at which plasma instability due to defects within the deposited film no longer occurs.

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