Window edge heater for high power plasma processing applications

Abstract

A window support system for a plasma processing chamber includes a window support frame configured to surround an opening. The window support frame has a top surface, a bottom surface, an inner surface, and an outer surface. Each of the inner surface and the outer surface extends between the top surface and the bottom surface. A channel is formed within the outer surface. The top surface is configured to mechanically and thermally interface with a peripheral portion of a window that is substantially transparent to radio frequency power. The window support system also includes a heating element disposed within the channel of the window support frame. The heating element is configured to substantially surround the window support frame.

Description

Background Art

[0001] Plasma processing systems are used to manufacture semiconductor devices, such as chips / die, on semiconductor wafers. In a plasma processing system, semiconductor wafers are exposed to various types of plasmas to cause a specified change in the state of the semiconductor wafer, such as through material deposition and / or material removal and / or material implantation and / or material modification, etc. During plasma processing of semiconductor wafers, radio frequency (RF) power is transmitted through a processing gas in a chamber to convert the processing gas into a plasma so that it contacts the semiconductor wafer. Reactive components (such as free radicals and ions) in the plasma interact with materials on the semiconductor wafer to produce a specified effect on the semiconductor wafer. In some plasma processing systems, RF power is transmitted from an antenna or coil through a window, such as an RF transparent ceramic structure, to a processing area in the chamber to convert the processing gas into plasma when contacting the semiconductor wafer.

[0002] In some plasma processing applications, sufficiently high RF power is transmitted from the antenna / coil to the chamber, coupled with sufficiently high pressure in the chamber, to cause a temperature gradient across the center to edge of the window that is too large, thereby causing mechanical failure of the window, such as cracking and / or breaking. For example, when plasma processing is performed at high power (e.g., antenna / coil power greater than about 2.5 kilowatts), a large temperature gradient is generated within the window due to the higher plasma temperature on the chamber side of the window, heat losses at the edges and top side (non-chamber side) of the window, and heat losses from the edge of the window to the chamber body. The large temperature gradient across the window from the center to the edge can cause stresses in the brittle ceramic material of the window, resulting in catastrophic failure of the window. In addition, larger windows (e.g., for applications where 300 mm substrates are processed) also produce larger temperature gradients and corresponding increased stresses. In addition, large temperature gradients across the window can cause non-uniformity across the wafer, such as similar to the so-called first wafer effect. The various embodiments described herein are generated in this context. Summary of the invention

[0003] In an exemplary embodiment, a window support system for a plasma processing chamber is disclosed. The window support system includes a window support frame configured to surround an opening. The window support frame has a top surface, a bottom surface, an inner surface, and an outer surface. Each of the inner surface and the outer surface extends between the top surface and the bottom surface. A channel is formed in the outer surface. The top surface is configured to mechanically and thermally interface with a peripheral portion of the window, and the window is substantially transparent to radio frequency power. The window support system also includes a heating element, which is disposed in the channel. The heating element is configured to substantially surround the window support frame.

[0004] In an exemplary embodiment, a plasma processing system is disclosed. The plasma processing system includes a chamber having a wall surrounding a plasma processing region. The plasma processing system also includes an adapter structure configured to dock with a top portion of the wall of the chamber. The adapter structure is configured to surround a first opening. The adapter structure has a flange portion that surrounds the first opening and extends into the first opening. The plasma processing system also includes a thermal insulator disposed on the flange portion of the adapter structure. The thermal insulator is formed as a continuous meandering structure. The plasma processing system also includes a window support frame disposed on the thermal insulator. The window support frame is configured to surround a second opening. The window support frame has a top surface, a bottom surface, an inner surface, and an outer surface. Each of the inner surface and the outer surface extends between the top surface and the bottom surface. The window support frame includes a channel formed in the outer surface. The plasma processing system also includes a heating element disposed in the channel of the window support frame. The heating element is configured to substantially surround the window support frame. The plasma processing system also includes a window disposed on a window support frame such that a meandering peripheral portion of the window is in thermal contact with the window support frame. The window is substantially transparent to radio frequency power.

[0005] In an exemplary embodiment, a method for controlling the temperature of a window of a plasma processing chamber is disclosed. The method includes supplying heat to a circuitous peripheral portion of the window by operating a heating element, the heating element sending heat to a window support frame, and the circuitous peripheral portion of the window is disposed on the window support frame. The method also includes monitoring the temperature of the circuitous peripheral portion of the window. The method also includes adjusting the supplied heat based on the monitored temperature to achieve and maintain a set point temperature of the circuitous peripheral portion of the window.

[0006] Other aspects and advantages of the embodiments disclosed herein will become more apparent from the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1A A vertical cross-sectional view of a portion of an exemplary substrate plasma processing system is shown in accordance with some embodiments.

[0008] Figure 1B A top view of a substrate plasma processing system is shown in accordance with some embodiments.

[0009] Figure 2A A top view of a substrate plasma processing system with coils and windows removed is shown in accordance with some embodiments.

[0010] Figure 2B Reference according to some embodiments is shown Figure 2A Vertical section through the window support system of view AA in.

[0011] Figure 2C Reference according to some embodiments is shown Figure 2B View BB in a horizontal section through the window support system.

[0012] Figure 3 A vertical exploded perspective view of a window support system according to some embodiments is shown.

[0013] Figure 4 An example diagram of a controller according to some embodiments is shown.

[0014] Figure 5 A flow chart illustrating a method of controlling a window temperature of a plasma processing chamber according to some embodiments. DETAILED DESCRIPTION

[0015] In the following description, many specific details are set forth to provide a thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that embodiments of the present disclosure may be implemented without some or all of these specific details. In other cases, well-known processing operations are not described in detail in order to avoid unnecessarily obscuring the present disclosure.

[0016] Disclosed herein are systems and methods for providing and using a heating structure on which a TCP (transformer coupled plasma) window is located to reduce the temperature gradient from the center to the edge of the entire TCP window when plasma processing operations are performed at high power and high pressure. For ease of description, the TCP window that separates the antenna / coil from the plasma processing area within the plasma processing chamber is referred to herein as a window. Heating the bottom peripheral edge region of the window can reduce or eliminate heat loss to the chamber body and increase the temperature of the peripheral edge region of the window to reduce the temperature gradient from the center to the edge of the entire window and correspondingly reduce stress accumulation in the window. In addition, by heating the peripheral edge region of the window, the first wafer effect can also be reduced, wherein the first wafer effect refers to the window having a lower temperature during the processing of a first substrate compared to the processing of a subsequent substrate, resulting in differences in processing results on the substrate.

[0017] Figure 1A A vertical cross-section through a portion of an exemplary substrate plasma processing system 100 is shown, according to some embodiments. Figure 1BA top view of a substrate plasma processing system 100 is shown according to some embodiments. The substrate plasma processing system 100 includes a chamber 101 that surrounds a plasma processing region 103. A substrate support structure 105 is disposed within the chamber 101 and is exposed to the plasma processing region 103. The substrate support structure 105 is configured to support a substrate 107 during processing of the substrate 107 by a plasma 109 generated above the substrate support structure 105. In some embodiments, the substrate support structure 105 is an electrostatic chuck that is configured to generate an electrostatic force to fix the substrate 107 on the substrate support structure 105.

[0018] The substrate plasma processing system 100 also includes an adapter structure 111 located on top of the chamber 101. In some embodiments, the adapter structure 111 is removable from the chamber 101, and one or more seals 113 are disposed between the adapter structure 111 and the chamber 101. In some embodiments, the one or more seals 113 are configured to provide a vacuum seal between the adapter structure 111 and the chamber 101. In other embodiments, the adapter structure 111 is integrally formed as a part of the chamber 101, so that the one or more seals 113 are not required to maintain the vacuum integrity of the plasma processing region 103. The adapter structure 111 is configured to surround the opening 112. The adapter structure 111 has a flange portion 111F that surrounds the opening 112 and extends into the opening 112. The adapter structure 111 is configured to support a window support frame 115 on the flange portion 111F. The window support frame 115 is used to support a window 117. In some embodiments, the window 117 is configured as a ceramic structure. In some embodiments, the window 117 is configured as a substantially disk-shaped ceramic structure. In some embodiments, the window 117 is configured as a ceramic showerhead structure that includes an arrangement of internal gas flow channels that are configured to receive a process gas supplied from a process gas source external to the chamber 101 and distribute the process gas into the plasma processing region 103, as indicated by arrows 119. The window 117 is substantially transparent to RF power, so that RF power emitted from a coil (or antenna 121) disposed above the window 117 can pass through the window 117 into the plasma processing region 103. It should be understood that in various embodiments, the window 117 can be formed of substantially any material, such as ceramic, quartz, etc., that is substantially transparent to RF power and is chemically, mechanically, and thermally compatible with the conditions within the plasma processing region 103 to which the window 117 is exposed.

[0019] The coil (or antenna) 121 is disposed above the window 117 to transmit RF power to the plasma processing region 103 through the window 117. In some embodiments, the coil 121 has a planar spiral shape (see Figure 1B ). For example, in Figure 1A In the cross-section of FIG. 1 , coil portion 121A extends out of the page and coil portion 121B extends into the page. It should be understood that in various embodiments, coil 121 can have substantially any configuration as long as coil 121 is configured to transmit RF power to plasma processing region 103 via window 117. In some embodiments, coil 121 is electrically connected to RF power source 123 via impedance matching network 125 to receive RF power from RF power source 123, as shown by electrical connection 127. In some embodiments, impedance matching network 125 is a network composed of capacitors and / or inductors for minimizing RF power reflection from coil 121, thereby optimizing RF power delivered to plasma 109 load.

[0020] RF power delivered from coil 121 to plasma processing region 103 converts the process gas / mixture into plasma 109 within plasma processing region 103. The generation of plasma 109 causes the substrate 107 to be changed in a controlled manner. The change in substrate 107 may be a change in material or surface conditions on substrate 107 in various manufacturing processes. For example, the change in substrate 107 may include one or more of etching of material on substrate 107, deposition of material on substrate 107, and / or modification of material on substrate 107 in various manufacturing processes. Used process gas / mixture and process byproduct materials are exhausted from plasma processing region 103, as indicated by arrow 129. It should be understood that plasma processing system 100 may be any type of plasma processing system in which RF power is delivered to process gas / mixture within plasma processing region 103 to generate plasma 109 on substrate 107 supported on substrate support structure 105.

[0021] In some embodiments, substrate 107 is a semiconductor wafer undergoing a manufacturing process. However, it should be understood that in various embodiments, substrate 107 can be substantially any type of substrate that undergoes a plasma-based manufacturing process. For example, in some embodiments, substrate 107 is formed of silicon, sapphire, gallium nitride (GaN), gallium arsenide (GaAs) or silicon carbide (SiC) and / or other substrate materials, and may include a glass plate / substrate, a metal foil, a metal sheet, a polymer material, or the like. In addition, in various embodiments, the form, shape, and / or size of substrate 107 may be different. For example, in some embodiments, substrate 107 is a semiconductor wafer having an outer diameter of 200 mm, 300 mm, 450 mm, or other sizes. In addition, in some embodiments, substrate 107 is a non-circular substrate, such as a rectangular substrate or the like for a flat panel display, as well as other shapes.

[0022] like Figure 1BAs shown, a top view of the substrate plasma processing system 100 identifies a cooling device 131 disposed within the adapter structure 111. In some embodiments, the adapter structure 111 is formed of a highly thermally conductive material (e.g., aluminum or other similarly thermally conductive material) that has sufficient mechanical strength to support the window 117 and is chemically compatible with the plasma processing performed within the plasma processing region 103. In some embodiments, the cooling device 131 is disposed in a groove or channel 133 formed in the adapter structure 111. In some embodiments, the groove / channel 133 is milled / machined / cast into the top surface of the adapter structure 111. However, it should be understood that in other embodiments, the cooling device 131 can be embedded in the adapter structure 111 in a different manner, such as via a groove formed on the outer surface of the adapter structure 111. The groove / channel 133 and the cooling device 131 are configured to substantially surround the window 117. The cooling device 131 is in thermal contact with the adapter structure 111 to provide conduction of heat from the adapter structure 111 to the cooling device 131. In some embodiments, the cooling device 131 is configured as a tube formed of a thermally conductive material (e.g., aluminum, copper, or other similar material) through which a cooling fluid flows. In some embodiments, the cooling fluid is water. However, in other embodiments, the cooling fluid can be substantially any flowable fluid having heat transfer properties suitable for removing heat from the adapter structure 111 and transferring the removed heat to an external heat sink. In some embodiments, the adapter structure 111 itself is not provided with an independent cooling device 131, but the adapter structure 111 itself forms an internal flow channel, through which the cooling fluid can flow to remove heat from the adapter structure 111. In some embodiments, the internal flow channel is configured to substantially surround the window 117 so that the cooling fluid can remove heat from the adapter structure 111 in a substantially uniform manner around the periphery of the window 117.

[0023] Figure 2A A top view of a substrate plasma processing system 100 after removing the coil 121 and the window 117 according to some embodiments is shown. The substrate plasma processing system 100 includes a window support system 134 for a plasma processing chamber 101. The window support system 134 includes a window support frame 115, a heating element 137 disposed around the window support frame 115, and a thermal insulation 139 disposed between the window support frame 115 and the adapter structure 111. The window support frame 115 is configured to surround an opening 140. Figure 2B Reference according to some embodiments is shown Figure 2A1 is a vertical section through the window support system 134 of view AA in FIG. The window support frame 115 has a top surface 115T, a bottom surface 115B, an inner surface 115I, and an outer surface 115O. Each of the inner surface 115I and the outer surface 115O extends between the top surface 115T and the bottom surface 115B. The top surface 115T of the window support frame 115 is configured to mechanically and thermally interface with the peripheral portion (edge ​​area) of the window 117. The window 117 is disposed on the window support frame 115 so that the circuitous peripheral portion of the window 117 is in thermal contact with the window support frame 115.

[0024] In some embodiments, a vacuum seal is established between the window 117 and the top surface 115T of the window support frame 115. In some embodiments, the top surface 115T of the window support frame 115 includes a groove 115G configured to receive a seal 141 for establishing a vacuum seal between the window support frame 115 and the window 117. It should be understood that in various embodiments, different sealing mechanisms can be used to establish a vacuum seal between the window support frame 115 and the window 117 as long as there is conductive heat transfer between the window 117 and the window support frame 115.

[0025] In some embodiments, the shape of the window support frame 115 is configured to substantially match the shape of the peripheral edge area of ​​the window 117. In some embodiments, the window support frame 115 is substantially annular, and the window 117 is a right cylindrical shape. In these embodiments, the peripheral portion of the window 117 that directly conducts heat to the window support frame 115 is the outer annular portion of the bottom surface 117B of the window 117. In some embodiments, the window support frame 115 is fixed to the adapter structure 111. For example, Figure 2A The window support frame 115 is shown secured to the adapter structure 111 by a plurality of fasteners 145-1 to 145-4. In some embodiments, the vacuum pressure generated within the plasma processing region 103 is sufficient to secure the window support frame 115 to the adapter structure 111, thus eliminating the need for fasteners such as 145-1 to 145-4.

[0026] The window support frame 115 has a radial thickness 161 (see Figure 2B ), which is measured between the inner surface 115I and the outer surface 115O of ​​the window support frame 115, wherein the radial thickness 161 is measured along the center point 163 of the opening 140 surrounded by the window support frame 115 (see Figure 2AIn some embodiments, the radial thickness 161 of the window support frame 115 is sized as small as possible while ensuring that the window support frame 115 is able to support the window 117 and provide a sufficient amount of surface contact area between the window support frame 115 and the window 117 to transfer heat from the heating element 137 to the window 117 through the window support frame 115, thereby achieving and maintaining a set point temperature for the peripheral edge region of the window 117.

[0027] In some embodiments, when the window support frame 115 is disposed on top of the insulation 139, which is disposed on the flange portion 111F of the adapter structure 111, the vertical height 165 of the window support frame 115 is defined such that the top surface 115T of the window support frame 115 is substantially coplanarly aligned with the top surface 111T of the adapter structure 111. Thus, in these embodiments, the vertical height 165 of the window support frame 115 is less than the vertical height 167 of the adapter structure 111. In these embodiments, the vertical height 169 of the flange portion 111F of the adapter structure 111 is defined such that the sum of the vertical height 169 of the flange portion 111F and the vertical height 171 of the insulation 139 and the vertical height 165 of the window support frame 115 is substantially equal to the vertical height 167 of the adapter structure 111. However, it should be understood that in some other embodiments, the vertical height 165 of the window support frame 115 is defined such that the top surface 115T of the window support frame 115 is above or below the top surface 111T of the adapter structure 111 .

[0028] Figure 2C A horizontal cross-sectional view through a window support system 134 is shown according to some embodiments, with reference to Figure 2BBB in FIG. In some embodiments, a channel 115C is formed in the outer surface 115O of ​​the window support frame 115. The channel 115C is configured to receive a heating element 137. The heating element 137 is disposed in the channel 115C. The heating element 137 is configured to substantially surround the window support frame 115. In some embodiments, the heating element 137 is fixed in the channel 115C by a spring force transmitted from the heating element 137 to the window support frame 115. In some embodiments, the heating element 137 is fixed in the channel 115C by potting, brazing, or substantially any other type of processing or connection technology, thereby establishing a strong mechanical connection and thermal connection between the heating element 137 and the window support frame 115. The heating element 137 directly conducts heat transfer with the window support frame 115. In some embodiments, the heating element 137 is a resistive heating element. In some embodiments, the cross-sectional shape of the channel 115C substantially matches the cross-sectional shape of the heating element 137. In some embodiments, the heating element has a substantially circular cross-sectional shape. In some embodiments, the heating element 137 is capable of increasing the temperature of the peripheral portion of the window 117 to at least 150 degrees Celsius by transferring heat to the window 117 via the window support frame 115 .

[0029] In some embodiments, the thermocouple insertion channel 115tc is formed along a portion of the channel 115C. In some embodiments, the thermocouple device 143 is inserted into the thermocouple insertion channel 115tc. In this way, in some embodiments, the thermocouple device 143 is disposed between the heating element 137 and the window support frame 115. In some embodiments, the thermocouple insertion channel 115tc extends a distance less than one-quarter of the circumferential distance around the window support frame 115. In some embodiments, the thermocouple insertion channel 115tc extends a distance less than one-eighth of the circumferential distance around the window support frame 115. In some embodiments, the distance that the thermocouple insertion channel 115tc extends along the channel 115C of the window support frame 115 just allows the thermocouple device 143 to be located between the heating portion of the heating element 137 and the window support frame 115. In some embodiments, as an alternative to or in addition to the thermocouple device 143, the heating element 137 itself is configured to include one or more embedded thermocouple devices having corresponding electrical connectors extending from the heating element 137 and the window support frame 115. In addition, in some embodiments, a plurality of thermocouple devices are disposed around the channel 115C of the window support frame 115 between the heating element 137 and the window support frame 115. In some embodiments, four or more thermocouple devices are disposed around the channel 115C of the window support frame 115. In some embodiments, the plurality of thermocouple devices are disposed substantially equally spaced around the opening 140 surrounded by the window support frame 115. In these embodiments, each of the plurality of thermocouple devices has a respective electrical connection extending out of the window support frame 115.

[0030] It should be understood that the window support frame 115 is configured to provide heat transfer between the heating element 137 and the peripheral portion (edge ​​region) of the window 117. In some embodiments, the heating element 137 is configured to substantially surround the window support frame 115, and correspondingly substantially surround the window 117 disposed on the window support frame 115, so that heat is transferred from the heating element 137 to the window 117 along the periphery of the window 117 in a substantially uniform manner. In some embodiments, the window support frame 115 is formed of a material having a high thermal conductivity (e.g., aluminum or a material of a higher order) that is chemically compatible with the plasma treatment performed in the plasma treatment region 103. In some embodiments, the window support frame 115 is formed of a material having a thermal conductivity of at least 200 W / mK (watts / meter-Kelvin). In some embodiments, the window support frame 115 is made of aluminum. In some embodiments, the window support frame 115 is made of copper. In some embodiments, the window support frame 115 is made of titanium. In some embodiments, the window support frame 115 is made of aluminum alloy, copper alloy, titanium alloy, or other materials having thermal conductivity similar to aluminum or copper or titanium.

[0031] Figure 3 A vertical exploded perspective view of the window support system 134 in some embodiments is shown. In some embodiments, the insulation 139 is formed as a continuous meandering structure. In some embodiments, the insulation 139 is disposed on the top surface 146 of the flange portion 111F of the adapter structure 111. The insulation 139 is configured to thermally isolate the bottom surface 115B of the window support frame 115 from the adapter structure 111 (or in some embodiments, from an upper structure of the chamber 101, which is equivalent to the adapter structure 111 but is integrally formed with the chamber 101). In some embodiments, the insulation 139 is formed of a material that can establish a vacuum seal between the insulation 139 and the window support frame 115 and can establish a vacuum seal between the insulation 139 and the adapter structure 111 (or the upper structure of the chamber 101). In some embodiments, one or more seals 147 are disposed between the thermal insulation 139 and the adapter structure 111 (or the upper structure of the chamber 101) to facilitate establishing a vacuum seal between the thermal insulation 139 and the adapter structure 111 (or the upper structure of the chamber 101). Additionally, in some embodiments, the adapter structure 111 (or the upper structure of the chamber 101) includes respective grooves 149 for receiving the seals 147.

[0032] In various embodiments, the thermal insulator 139 is made of an insulating material that provides sufficient mechanical strength to support the window support frame 115 and the window 117, that is chemically compatible with the materials in the plasma processing region 103, and that is thermally compatible with the temperature of the window support frame 115 generated by the heating element 137. In some embodiments, the thermal insulator 139 is made of a plastic material. In some embodiments, the thermal insulator 139 is formed of a ceramic material. In some embodiments, the thermal insulator 139 is made of a stainless steel material. In some embodiments, the thermal insulator 139 is made of polyetheretherketone (PEEK). In order to improve the electrical efficiency and performance of the window support system 134, and to improve the thermal efficiency and performance of the window support system 134, it is best to transfer the heat output by the heating element 137 to the window 117 via the window support frame 115 as much as possible. Therefore, in some embodiments, the size and location of the window support frame 115 will not substantially conduct heat directly to the adapter structure 111 (or the upper structure of the chamber 101). Figure 2B An exemplary embodiment is shown in which, when the window support frame 115 and the thermal insulation 139 are disposed together on the top surface 146 of the flange portion 111F of the adapter structure 111, a gap 151 exists between the outer surface 115O of ​​the window support frame 115 and the adapter structure 111. The gap 151 extends around the entire outer surface 115O of ​​the window support frame 115 so that there is no direct heat conduction between the outer surface 115O of ​​the window support frame 115 and the adapter structure 111. In some embodiments, the gap 151 is an air gap. In some embodiments, a thermal insulation material is disposed in at least a portion of the gap 151. In some embodiments, the thermal insulation material disposed in the gap 151 is the same material as that forming the thermal insulation 139. In some embodiments, the thermal insulation material disposed in the gap 151 is integrally formed with the thermal insulation 139. In some embodiments, a heat reflector is disposed in at least a portion of the gap 151, wherein the heat reflector is configured to reflect heat emitted from the heating element 137 back into the window support frame 115. In some embodiments, the heat reflector disposed in the gap 151 is integrally formed with the thermal insulation 139 .

[0033] In some embodiments, the inner surface 115I of the window support frame 115 is coated with a protective coating. In some embodiments, the protective coating on the window support frame 115 is a plasma-resistant coating. In some embodiments, the protective coating on the window support frame 115 is one or more of an anodized coating, a ceramic coating, and a yttrium-based coating. In other embodiments, the protective coating on the inner surface 115I of the window support frame 115 can be substantially any type of plasma-resistant coating used in the semiconductor manufacturing industry. In addition, in some embodiments, the surface of the adapter structure 111 exposed to the plasma processing region 103 is also coated with a protective coating. In some embodiments, the protective coating on the adapter structure 111 is a plasma-resistant coating. In some embodiments, the protective coating on the adapter structure 111 is one or more of an anodized coating, a ceramic coating, and a yttrium-based coating. In other embodiments, the protective coating on the adapter structure 111 is substantially any type of plasma-resistant coating used in the semiconductor manufacturing industry. In some embodiments, the protective coating on the adapter structure 111 is the same as the protective coating on the window support frame 115.

[0034] like Figure 2A and Figure 3As shown, the temperature measuring device 153 is disposed on the connection block 115X of the window support frame 115. The connection block 115X is configured to support the first lead terminal 137A and the second lead terminal 137B of the heating element 137. In some embodiments, the temperature measuring device 153 is electrically connected to the controller 155 via the electrical connection 157. In this way, the controller 155 receives a signal from the temperature measuring device 153 indicating the measured temperature of the connection block 115X. In some embodiments, the temperature measuring device 153 is used to monitor an overheating condition, which triggers the controller 155 to disconnect the heating element 137 from its power supply. In some embodiments, the connection block 115X is configured to include a channel for inserting the thermocouple device 143 into the thermocouple insertion channel 115tc, so that when the heating element 137 is fixed in the channel 115C of the window support frame 115, the thermocouple device 143 can be inserted into the thermocouple insertion channel 115tc and removed therefrom. In some embodiments, the first lead terminal 137A and the second lead terminal 137B of the heating element 137 are electrically connected to a power source. The controller 155 is configured and programmed to control the power supply to the heating element 137, thereby controlling the temperature of the window support frame 115, and thereby controlling the temperature of the peripheral edge area of ​​the window 117. In some embodiments, the temperature measurement performed by the thermocouple device 143 is used to control the heating element 137. For example, in some embodiments, the controller 155 is configured to implement a PID (proportional integral differential) control system, which uses the temperature measurement of the thermocouple device 143 to actively control the heating element 137 to reach and maintain the set point operating temperature of the peripheral edge area of ​​the window 117. In some embodiments, the set point operating temperature of the peripheral edge area of ​​the window 117 is programmed into the controller 155. In some embodiments, the set point operating temperature of the peripheral edge area of ​​the window 117 is about 150 degrees Celsius. In some embodiments, the set point operating temperature of the peripheral edge area of ​​the window 117 is higher than about 150 degrees Celsius. The heating element 137 has an operable power range that enables the peripheral edge region of the window 117 to reach and maintain a set point operating temperature. In some embodiments, the output power of the heating element 137 is approximately 3 kW. However, it should be understood that in various other embodiments, the output power of the heating element 137 is less than 3 kW or greater than 3 kW.

[0035] Figure 4An example diagram of a controller 155 according to some embodiments is shown. In some embodiments, the controller 155 includes a processor 409, a storage hardware unit (HU) 411 (e.g., memory), an input HU401, an output HU405, an input / output (I / O) interface 403, an I / O interface 407, a network interface controller (NIC) 415, and a data communication bus 413. The processor 409, the storage HU411, the input HU401, the output HU405, the I / O interface 403, the I / O interface 407, and the NIC415 communicate data with each other via the data communication bus 413. Examples of the input HU401 include a mouse, a keyboard, a stylus, a data acquisition system, a data acquisition card, etc. Examples of the output HU405 include a display, a speaker, a device controller, etc. Examples of the NIC415 include a network interface card, a network adapter, etc. In various embodiments, the NIC415 is configured to operate in accordance with one or more communication protocols and associated physical layers (e.g., Ethernet and / or EtherCAT, etc.). Each I / O interface 403 and 407 is defined to provide compatibility between different hardware units coupled to the I / O interface. For example, the I / O interface 403 may be defined to convert signals received from the input HU 401 into a form, amplitude, and / or speed compatible with the data communication bus 413. In addition, the I / O interface 407 may be defined to convert signals received from the data communication bus 413 into a form, amplitude, and / or speed compatible with the output HU 405. Although the various operations described herein are performed by the processor 409 of the controller 155, it should be understood that in some embodiments, the various operations may be performed by multiple processors of the controller 155 and / or multiple processors of multiple computing systems connected to the controller 155.

[0036] In various embodiments, the substrate plasma processing system 100 is integrated with electronics for controlling its operation before, during, and after processing of the substrate 107, wherein the electronics are implemented in a controller 155 that is configured and connected to control various components and / or subcomponents of the substrate plasma processing system 100, including the window support system 134. Depending on the processing requirements of the substrate 107 and / or the particular configuration of the substrate plasma processing system 100, the controller 155 may be programmed to control any of the processes and / or components disclosed herein, including the delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, RF power system settings, electrical signal frequency settings, gas flow rate settings, fluid delivery settings, position and operation settings, bias supply system settings, movement of the substrate 107 into and out of the chamber 101 and / or into and out of a load lock connected or docked to the substrate plasma processing system 100, and the like.

[0037] In various embodiments, the controller 155 is defined as an electronic device having various integrated circuits, logic, memory and / or software that manages and controls various tasks / operations, such as receiving instructions, issuing instructions, controlling equipment operations, performing cleaning operations, performing endpoint measurements, performing metrology measurements (optical, thermal, electrical, etc.), and other tasks / operations. In some embodiments, the integrated circuits within the controller 155 include one or more of a computing device such as a firmware storing program instructions, a digital signal processor (DSP), an application specific integrated circuit (ASIC) chip, a programmable logic device (PLD), one or more microprocessors, and / or one or more microcontrollers that execute program instructions (e.g., software). In some embodiments, the program instructions are transmitted to the controller 155 in the form of individual settings (or program files) that define the command parameters for performing processing on the substrate 107 within the substrate plasma processing system 100. In some embodiments, the instruction parameters are included in a recipe defined by a process engineer to complete one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies on substrate 107.

[0038] In some embodiments, the controller 155 is part of a computer integrated or connected to the substrate plasma processing system 100, or is otherwise networked to the substrate plasma processing system 100, or a combination thereof. For example, in some embodiments, the controller 155 is implemented in the "cloud", or in all or part of a wafer fab host computer system, thereby allowing remote access to control the processing of the substrate 107 by the substrate plasma processing system 100. The controller 155 allows remote access to the substrate plasma processing system 100 to monitor the current progress of manufacturing operations, review the history of past manufacturing operations, review trends or performance indicators from multiple manufacturing operations, change processing parameters, set subsequent processing steps, specify operating parameters of RF power system instructions, specify operating parameters of the bias supply system, specify operating parameters of the window support system 134, and / or initiate a new substrate manufacturing process.

[0039] In some embodiments, a remote computer (e.g., a server computer system) provides a process recipe to the controller 155 via a computer network (including a local area network and / or the Internet). The remote computer includes a user interface that can input or program parameters and / or settings, which are then transmitted from the remote computer to the controller 155. In some examples, the controller 155 receives instructions in the form of settings for processing the substrate 107 in the substrate plasma processing system 100. It should be understood that these settings are specific to the type of process to be performed on the substrate 107 and the type of tool / equipment / component that the controller 155 interfaces with or controls. In some embodiments, the controller 155 is distributed, such as including one or more independent controllers 155 that are connected via a network and work synchronously for a common purpose, such as operating the substrate plasma processing system 100 to perform a specified process on the substrate 107. Examples of distributed controllers 155 for such purposes include one or more integrated circuits on the chamber that communicate with one or more integrated circuits located remotely (e.g., at the platform level or as part of a remote computer), which together control the process in the chamber 101.

[0040] Figure 5A flow chart of a method for controlling the temperature of a window 117 of a plasma processing chamber 101 is shown according to some embodiments. The method includes an operation 501 for providing heat to a circuitous peripheral portion of the window 117 by operating a heating element 137 to release heat to a window support frame 115, the circuitous peripheral portion of the window 117 being disposed on the window support frame 115. In some embodiments, the window 117 is in thermal conductive contact with a top surface 115T of the window support frame 115, wherein the window support frame 115 is configured to surround an opening 140. The window support frame 115 has an inner surface 115I and an outer surface 115O. Each of the inner surface 115I and the outer surface 115O extends between a top surface 115T and a bottom surface 115B of the window support frame 115. The window support frame 115 also includes a channel 115C formed in the outer surface 115O. The heating element 137 is disposed in the channel 115C. The heating element 137 is configured to substantially surround the window support frame 115. The window 117 is substantially transparent to RF power. The method further includes an operation 503 for monitoring the temperature of the circuitous peripheral portion of the window 117. The method further includes an operation 505 for adjusting the heat supplied in operation 501 based on the temperature monitored in operation 503 to reach and maintain a set point temperature of the circuitous peripheral portion of the window 117. In some embodiments, operation 503 monitors the temperature based on a threshold. If the detected temperature exceeds the threshold, the controller 155 will automatically stop (or pause) supplying heat to the circuitous peripheral portion of the window 117. This will prevent the window from accidentally overheating. In some embodiments, the heating element 137 is operated to increase the temperature of the window support frame 115, and correspondingly increase the temperature of the peripheral area of ​​the window 117 to a set temperature greater than or equal to about 150 degrees Celsius. In some embodiments, the method further includes introducing a cooling gas (e.g., air) into a central area of ​​the top surface of the window 117, such as Figure 1A As shown by arrows 159 in the figure, the radial temperature gradient of the entire window 117 from the center to the edge is further reduced.

[0041] In some embodiments, the method includes disposing a thermal insulation 139 between the window support frame 115 and the adapter structure 111. In these embodiments, the adapter structure 111 is configured to support the thermal insulation 139 and the window support frame 115. The adapter structure 111 is also configured to extend around the outer surface 115O of ​​the window support frame 115 without obstructing the opening 140 surrounded by the window support frame 115 and without contacting the window support frame 115. In some embodiments, the method also includes flowing a cooling fluid through a cooling device 131 disposed within the adapter structure 111. In some embodiments, the cooling device 131 is configured to extend around the periphery of the window support frame 115. In some embodiments, the cooling device 131 is a conduit through which the cooling fluid flows.

[0042] The window support system 134 thermally decouples the window 117 from the heat sink of the adapter structure 111 and / or the chamber 101. It should be appreciated that without the window support system 134, in some substrate plasma processing applications, the heat sink provided by the adapter structure 111 and / or the chamber 101 may generate a sufficiently large temperature gradient in the window 117 to cause thermal stress fracture of the window 117. The window support system 134 introduces a heat source at the peripheral edge of the window 117 to reduce heat loss from the edge of the window 117 to the adapter structure 111 and / or the chamber 101, thereby reducing the thermal gradient and correspondingly reducing the stress of the window 117. In various embodiments, the window support system 134 is configured to be mounted into an existing plasma processing chamber body to maintain the existing geometric relationship between the window 117 and the plasma processing chamber to achieve process compatibility. In addition, the implementation and use of the window support system 134 avoids the problem of having to attempt to heat the chamber body in order to maintain the integrity of the window 117, which may lead to many other problems, such as the complexity of the power required, safety issues of heating the chamber body (in excess of 100 degrees Celsius), and compatibility with other devices connected to the chamber (such as pressure gauges, valves, etc.).

[0043] In some embodiments, the window support system 134 can maintain the integrity of the window 117 in high power plasma processing applications where the coil 121 power is greater than or equal to about 2 kilowatts and the pressure within the plasma processing region 103 is greater than or equal to about 100 millitorr. It should be appreciated that the window support system 134 provides an improvement over simply thermally insulating the window 117 from the adapter structure 111 and / or the chamber 101. Specifically, the window support system 134 completely eliminates the thermal impact of the adapter structure 111 and / or the chamber 101 on the heat sink of the window 117 and provides a heat source at the edge of the window 117. The window support system 134 is particularly helpful in maintaining the structural integrity of the larger diameter window 117 when the substrate plasma processing system 100 is configured to process larger diameter substrates 107 (e.g., 300 mm or larger diameter substrates 107), in which case the larger diameter window 117 requires a lower center-to-edge temperature gradient to avoid cracking / shattering of the window 117. The heat output by the window support system 134 increases the temperature around the edge of the window 117 and correspondingly reduces the temperature gradient from the center to the edge of the window 117, thereby enabling the window 117 to operate properly in high power / high pressure substrate plasma processing applications. As an additional benefit, the window support system 134 can be used to reduce or eliminate the first wafer effect.

[0044] The various embodiments described herein can be used in conjunction with various computer system configurations, including handheld hardware units, microprocessor systems, microprocessor-based or programmable consumer electronic devices, microcomputers, mainframe computers, etc. The various embodiments described herein can also be implemented in conjunction with a distributed computing environment, in which tasks are performed by remote processing hardware units connected via a computer network. It should also be understood that the various embodiments disclosed herein include various computer-executed operations involving data stored in a computer system. The operations performed by these computers are operations that manipulate physical quantities. In various embodiments, the operations performed by the computer are performed by a general-purpose computer or a special-purpose computer. In some embodiments, the operations performed by the computer are performed by a selectively activated computer, and / or are managed by one or more computer programs stored in a computer memory or obtained via a computer network. When a computer program and / or digital data is obtained via a computer network, the digital data can be processed by other computers on the computer network (such as a computing resource cloud). Computer programs and digital data are stored on non-transient computer-readable media as computer-readable code. Non-transient computer-readable media are any data storage hardware units that store data, such as memory devices, etc., which can be read by a computer system thereafter. Examples of non-transitory computer-readable media include hard disks, network attached storage devices (NAS), ROM, RAM, compact disk-ROM (CD-ROM), recordable CD (CD-R), rewritable CD (CD-RW), digital video / versatile disk (DVD), magnetic tape, and other optical and non-optical data storage hardware units. In some embodiments, the computer program and / or digital data are distributed among multiple computer-readable media in different computer systems within a network of coupled computer systems, so that the computer program and / or digital data are executed and / or stored in a distributed manner.

[0045] Although the above disclosure includes some details for the purpose of clarity of understanding, it is apparent that certain changes and modifications may be made within the scope of the appended claims. For example, it should be understood that one or more features of any embodiment disclosed herein may be combined with one or more features of any other embodiment disclosed herein. Therefore, the present embodiments should be regarded as illustrative rather than restrictive, and the scope of protection requested is not limited to the details given herein, but may be modified within the scope of the embodiments and equivalents.

[0046] The scope of protection requested is:

Claims

1. A window support system for a plasma processing chamber, comprising: a window support frame configured to surround an opening, the window support frame having a top surface, a bottom surface, an inner surface, and an outer surface, each of the inner surface and the outer surface extending between the top surface and the bottom surface, wherein a channel is formed in the outer surface, the top surface being configured to mechanically and thermally interface with a peripheral portion of a window, the window being substantially transparent to radio frequency power; and A heating element is disposed within the channel, the heating element being configured to substantially surround the window support frame.

2. The window support system for a plasma processing chamber according to claim 1, further comprising: A thermocouple is inserted into the passage and is formed along a portion of the passage.

3. The window support system for a plasma processing chamber of claim 2, further comprising: A thermocouple device is provided, which inserts the thermocouple into the channel.

4. The window support system for a plasma processing chamber of claim 1 , wherein the window support frame is substantially annular, the window has a right cylindrical shape, and the peripheral portion of the window is an outer annular portion of a bottom surface of the window.

5. The window support system for a plasma processing chamber of claim 1, wherein the top surface of the window support frame comprises a groove configured to receive a seal for establishing a vacuum seal between the window support frame and the window.

6. The window support system for a plasma processing chamber of claim 1, wherein the window support frame is made of a material having a thermal conductivity of at least 200 Watts / meter-Kelvin.

7. The window support system for a plasma processing chamber of claim 1, wherein the window support frame is made of aluminum.

8. The window support system for a plasma processing chamber of claim 1, wherein the inner surface of the window support frame is coated with a plasma resistant coating.

9. The window support system for a plasma processing chamber of claim 8, wherein the plasma resistant coating is one or more of an anodic oxidation coating, a ceramic coating, and a yttrium-based coating.

10. The window support system for a plasma processing chamber of claim 1, further comprising: A thermal insulator is configured to thermally insulate the bottom surface of the window support frame from a structure of the plasma processing chamber, the thermal insulator being formed as a continuous meandering structure.

11. The window support system for a plasma processing chamber of claim 10, wherein the thermal insulation is made of a plastic material.

12. The window support system for a plasma processing chamber of claim 1, wherein the window support frame is sized and positioned such that substantially no heat is directly conducted to the structure of the plasma processing chamber.

13. A plasma processing system comprising: a chamber having walls surrounding a plasma processing region; an adapter structure configured to interface with a top portion of the wall of the chamber, the adapter structure configured to surround a first opening, the adapter structure having a flange portion surrounding the first opening and extending into the first opening; a thermal insulator disposed on the flange portion of the adapter structure, the thermal insulator being formed as a continuous meandering structure; a window support frame disposed on the thermal insulation, the window support frame being configured to surround the second opening, the window support frame having a top surface, a bottom surface, an inner surface, and an outer surface, each of the inner surface and the outer surface extending between the top surface and the bottom surface, the window support frame including a channel formed in the outer surface; a heating element disposed within the channel of the window support frame, the heating element being configured to substantially surround the window support frame; as well as A window is disposed on the window support frame such that a meandering peripheral portion of the window is in thermal contact with the window support frame, the window being substantially transparent to radio frequency power.

14. The plasma processing system of claim 13, wherein said adapter structure includes a cooling device configured to extend around said first opening, said cooling device being disposed in thermally conductive contact with said adapter structure.

15. The plasma processing system of claim 14 wherein the cooling device is a conduit through which a cooling fluid flows.

16. The plasma processing system of claim 15 wherein said conduit is disposed in a passage within said adapter structure.

17. The plasma processing system of claim 13 wherein a size of said first opening in said adapter structure is larger than a size of said window support frame such that a gap exists between said outer surface of said window support frame and said adapter structure.

18. A method for controlling the temperature of a window of a plasma processing chamber, comprising: supplying heat to a circuitous peripheral portion of a window by operating a heating element, the heating element sending heat to a window support frame on which the circuitous peripheral portion of the window is disposed; monitoring a temperature of the circuitous peripheral portion of the window; as well as The heat supplied is adjusted based on the monitored temperature to achieve and maintain a set point temperature of the circuitous peripheral portion of the window.

19. The method according to claim 18, further comprising: A flow of cooling gas is directed to a central region of the top surface of the window.

20. The method of claim 18, wherein the set point temperature is greater than or equal to about 150 degrees Celsius.

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