Sensor system for multi-zone electrostatic chucks

Abstract

A heater assembly for a substrate support assembly is provided that allows for both lateral and azimuthal adjustment of heat transfer between an electrostatic chuck and the heating assembly. In a processing chamber, a heater assembly for a substrate support assembly includes a body, one or more primary resistive heating elements disposed within the body, a plurality of additional heating elements disposed within the body, and a plurality of temperature sensors disposed within the body, wherein one or more of the plurality of temperature sensors are disposed proximate to one of the plurality of additional heating elements.

Description

[Technical Field]

[0001] TECHNICAL FIELD Embodiments described herein relate generally to semiconductor manufacturing, and more particularly to a temperature-controlled substrate support assembly and method of using the same.

[0002] As feature sizes in integrated circuit device patterns become smaller, the critical dimension (CD) specifications of these features become more important criteria for stable and repeatable device performance. Acceptable CD variation across substrates processed in a processing chamber is difficult to achieve due to chamber asymmetries (e.g., chamber and substrate temperatures, flow conductance, RF fields, etc.).

[0003] In processes using electrostatic chucks, achieving uniform temperature control across the surface of the substrate is even more difficult due to the non-uniform structure of the chuck underneath the substrate. For example, some regions of the electrostatic chuck have gas holes, while other regions have lift pin holes laterally offset from the gas holes. Furthermore, other regions have chuck electrodes, while other regions have heater electrodes laterally offset from the chuck electrodes. Because the structure of an electrostatic chuck can vary both laterally and azimuthally, achieving uniform heat transfer between the chuck and the substrate is complex and very difficult, resulting in localized hot and cold spots across the chuck surface, which in turn results in non-uniform processing results along the surface of the substrate.

[0004] The lateral and azimuthal uniformity of heat transfer between the chuck and the substrate is further complicated by the heat transfer scheme commonly used in conventional substrate supports to which the electrostatic chuck is attached. For example, conventional substrate supports typically have only edge-to-center temperature control. Localized hot and cold spots within the electrostatic chuck cannot be compensated for using the heat transfer features of conventional substrate supports.

[0005] The embodiments described herein provide a substrate support assembly that allows for both lateral and azimuthal adjustment of heat transfer between the electrostatic chuck and the heating assembly.

[0006] In one embodiment, a heater assembly for a substrate support assembly includes a body and one or more primary resistive heating elements disposed within the body. The heater assembly further includes a plurality of additional resistive heating elements disposed within the body, each of which may be referred to herein as a partially adjustable heating element. The heater assembly further includes a plurality of temperature sensors disposed within the body, each of which is positioned proximate to one of the plurality of additional resistive heating elements.

[0007] In one embodiment, a substrate support assembly includes an electrostatic chuck including a ceramic body, an electrode disposed within the ceramic body, and a plurality of heating elements disposed within the ceramic body. The substrate support assembly further includes a plurality of temperature sensors disposed at least one of 1) within the ceramic body or 2) on a bottom surface of the ceramic body, each of the plurality of temperature sensors positioned proximate to one of the plurality of heating elements and adapted to detect operability of the heating elements.

[0008] In one embodiment, an apparatus includes a flexible polymer body having a disk shape and a plurality of temperature sensors disposed within the flexible polymer body, each of the plurality of temperature sensors for measuring a temperature of a region of the electrostatic chuck. [Brief explanation of the drawings]

[0009] So that the foregoing features of the present invention can be understood in detail, a more particular description, briefly summarized above, can be had by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings illustrate only some embodiments of the present invention and should not be construed as limiting its scope. [Figure 1] 1 is a cross-sectional schematic side view of a processing chamber having one embodiment of a substrate support assembly. [Figure 2] 1 is a schematic side view, partially in cross section, showing portions of a substrate support assembly in greater detail; [Figure 3A] ~ [Figure 3F] 1 is a partial schematic side view showing various positions of a partially adjustable heater and a primary resistive heater within a substrate support assembly. [Figure 4A] FIG. 3 is a cross-sectional view taken along the line AA in FIG. 2. [Figure 4B] ~ [Figure 4D] 3 is a cross-sectional view taken along section line AA of FIG. 2 showing an alternative layout of a partially adjustable heater. [Figure 5] FIG. 10 shows a wiring diagram for a partially adjustable heater and a main resistive heater. [Figure 6] FIG. 10 shows an alternative wiring diagram for a partially adjustable heater and a main resistive heater. [Figure 7] FIG. 7 is a bottom perspective view of a substrate support assembly configured for the wiring diagram depicted in FIG. 6. [Figure 8] FIG. 7 is a bottom perspective view of a cooling base configured for the wiring diagram shown in FIG. 6. [Figure 9] 1 is a flow diagram of an embodiment of a method for processing a substrate using a substrate support assembly. [Figure 10] FIG. 10 is a cross-sectional view of a mating connector for connecting the electrostatic chuck to a controller.

[0010] To facilitate understanding, the same reference numbers have been used, whenever possible, to designate identical elements common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially used on other embodiments without specific recitation. DETAILED DESCRIPTION

[0011]

[0006] Embodiments described herein provide a substrate support assembly that allows for lateral and azimuthal adjustment of the temperature of an electrostatic chuck, which in turn allows for both lateral and azimuthal adjustment of the lateral temperature profile of a substrate being processed on the substrate support assembly. Furthermore, embodiments allow for monitoring of the temperature at many different locations within the substrate support assembly. Methods for adjusting the lateral temperature profile of a substrate being processed on the substrate support assembly are also described herein.

[0012] In embodiments, the substrate support assembly includes multiple heating zones. Each heating zone can be heated by a heating element disposed in that heating zone. The substrate support assembly can include anywhere from two heating zones to hundreds of heating zones (e.g., 150 heating zones or 200 heating zones in some embodiments). Each heating zone includes an individual temperature sensor, which may be a resistance temperature detector (RTD) or a thermocouple. Multiple heating elements may share one or more common grounds, and the temperature sensors may share one or more additional common grounds. Thus, the number of wires used to power multiple heating elements may be one more than the number of heating elements, and the number of wires used to power temperature sensors may be one more than the number of heating elements. Having a separate temperature sensor for each heating element allows the temperature controller to determine when any heating element has failed. Furthermore, if the temperature sensors are calibrated, each of the heating elements can determine the temperature in a particular heating zone, which can be used for feedback control of the heating element associated with that heating zone.

[0013] Although the substrate support assembly is described below in an etch processing chamber, the substrate support assembly can be used in other types of processing chambers (such as physical vapor deposition chambers, chemical vapor deposition chambers, ion implantation chambers, etc., among others) and other systems where azimuthal adjustment of the lateral temperature profile may be desirable. It is further contemplated that the locally adjustable heater can be used to control the temperature of other surfaces (including those not used in semiconductor processing).

[0014] In one or more embodiments, the substrate support assembly enables correcting critical dimension (CD) variations at the edge of the substrate during a vacuum process (e.g., etch, deposition, implant, etc.) based on adjusting the substrate temperature, thereby compensating for chamber non-uniformities (e.g., temperature, flow conductance, electric field, plasma density, etc.). Additionally, some embodiments provide a substrate support assembly that can control temperature uniformity across the substrate to less than about ±0.3°C.

[0015] 1 is a cross-sectional schematic view of an exemplary etch processing chamber 100 having a substrate support assembly 126. As discussed above, the substrate support assembly 126 can also be used in other processing chambers (e.g., plasma processing chambers, annealing chambers, physical vapor deposition chambers, chemical vapor deposition chambers, ion implantation chambers, etc.). Additionally, the substrate support assembly 126 can be used in other systems where the ability to control the temperature profile of a surface or workpiece (e.g., a substrate, etc.) is desirable. Independent local control of temperature over many discrete regions across a surface advantageously allows for azimuthal adjustment of the temperature profile, center-to-edge adjustment of the temperature profile, and reduction of local temperature non-uniformities such as hot and cold spots.

[0016] In one embodiment, the processing chamber 100 includes a grounded chamber body 102. The chamber body 102 includes walls 104, a bottom 106, and a lid 108 that enclose an interior volume 124. A substrate support assembly 126 is disposed in the interior volume 124 and supports a substrate 134 during processing.

[0017] The walls 104 of the processing chamber 100 may include openings (not shown) that allow for robotic transfer of substrates 134 into and out of the interior volume 124. A pumping port 110 is formed in one of the walls 104 or bottom 106 of the chamber body and is fluidly connected to a pumping system (not shown). The pumping system can maintain a vacuum environment within the interior volume 124 of the processing chamber 100 and can remove processing by-products from the processing chamber.

[0018] A gas panel 112 can provide process gases and / or other gases to an interior volume 124 of the processing chamber 100 through one or more inlet ports 114 formed in the lid 108 and / or walls 104 of the chamber body 102. The process gases provided by the gas panel 112 are excited within the interior volume 124 to form a plasma 122 that is used to process a substrate 134 disposed on a substrate support assembly 126. The process gases are excited by RF power inductively coupled to the process gases from a plasma applicator 120 disposed outside the chamber body 102. In the embodiment shown in FIG. 1 , the plasma applicator 120 is a pair of coaxial coils coupled to an RF power source 116 via a matching network 118.

[0019] A controller 148 is coupled to the processing chamber 100 and controls its operation and the processing of the substrate 134. The controller 148 may be a general-purpose data processing system that can be used in industrial settings to control various sub-processors and sub-controllers. Generally, the controller 148 includes a central processing unit (CPU) 172 in communication with a memory 174 and input / output (I / O) circuitry 176, among other common components. Software commands executed by the CPU of the controller 148 cause the processing chamber to, for example, introduce an etchant gas mixture (i.e., process gases) into the interior volume 124, form a plasma 122 from the process gases by application of RF power from the plasma applicator 120, and etch a layer of material on the substrate 134.

[0020] The substrate support assembly 126 generally includes at least one substrate support 132. The substrate support 132 may be a vacuum chuck, an electrostatic chuck, a susceptor, or other workpiece support surface. In the embodiment of FIG. 1, the substrate support 132 is an electrostatic chuck, and is hereinafter referred to as an electrostatic chuck 132. The substrate support assembly 126 may further include a heater assembly 170, which includes a primary resistive heating element 154 (also referred to as a primary resistive heater) and a plurality of additional resistive heating elements (also referred to as partially adjustable heaters), referred to as partially adjustable heating elements.

[0021] The substrate support assembly 126 may also include a cooling base 130. The cooling base 130 may optionally be separate from the substrate support assembly 126. The substrate support assembly 126 may be removably coupled to a support pedestal 125. The support pedestal 125 may include a pedestal base 128 and a facility plate 180 and is attached to the chamber body 102. The substrate support assembly 126 may be periodically removed from the support pedestal 125 to allow for refurbishing of one or more components of the substrate support assembly 126.

[0022] The facility plate 180 is configured to house one or more drive mechanisms configured to raise and lower the plurality of lift pins. Additionally, the facility plate 180 is configured to house fluid connections from the electrostatic chuck 132 and the cooling base 130. The facility plate 180 is also configured to house electrical connections from the electrostatic chuck 132 and the heater assembly 170. The myriad connections can be made external or internal to the substrate support assembly 126, and the facility plate 180 can provide an interface for connections to each end.

[0023] The electrostatic chuck 132 has a mounting surface 131 and a workpiece surface 133 opposite the mounting surface 131. The electrostatic chuck 132 generally includes a chucking electrode 136 embedded in a dielectric 150. The chucking electrode 136 may be configured as a monopolar or bipolar electrode, or any other suitable arrangement. The chucking electrode 136 may be coupled to a chucking power supply 138 through a radio frequency (RF) filter 182, which provides RF or direct current (DC) power to electrostatically secure the substrate 134 to the upper surface of the dielectric 150. The RF filter 182 prevents the RF power used to form the plasma 122 within the processing chamber 100 from damaging electrical equipment or posing an electrical hazard outside the chamber. The dielectric 150 may be fabricated from a ceramic material (e.g., AlN or Al2O3). Alternatively, the dielectric 150 can be made from a polymer (eg, polyimide, polyetheretherketone, polyaryletherketone, etc.).

[0024] The workpiece surface 133 of the electrostatic chuck 132 may include gas passages (not shown) for supplying a backside thermal transfer gas to a gap defined between the substrate 134 and the workpiece surface 133 of the electrostatic chuck 132. The electrostatic chuck 132 also includes lift pin holes for accommodating lift pins (both not shown) for lifting the substrate 134 above the workpiece surface 133 of the electrostatic chuck 132, thereby facilitating robotic transfer in and out of the processing chamber 100.

[0025] The temperature-controlled cooling base 130 is coupled to a heat transfer fluid source 144. The heat transfer fluid source 144 provides a heat transfer fluid (e.g., a liquid, a gas, or a combination thereof) that is circulated through one or more conduits 160 disposed within the cooling base 130. Fluid flowing through adjacent conduits 160 is isolated, allowing for localized control of heat transfer between different regions of the electrostatic chuck 132, substrate 134, and cooling base 130, which aids in controlling the lateral temperature profile of the substrate 134.

[0026] A fluid distributor (not shown) may be fluidly coupled between the outlet of the heat transfer fluid source 144 and the temperature-controlled cooling base 130. The fluid distributor operates to control the amount of heat transfer fluid supplied to the conduit 160. The fluid distributor may be located outside the processing chamber 100, within the substrate support assembly 126, within the pedestal base 128, or in another suitable location.

[0027] The heater assembly 170 may include one or more primary resistive heaters 154 embedded in the body 152 and / or multiple locally adjustable heaters 140. Additionally, the body 152 may include multiple temperature sensors. Each of the multiple temperature sensors may be used to measure the temperature of a region of the heater assembly and / or a region of the electrostatic chuck associated with the region of the heater assembly. In one embodiment, the body 152 is a flexible polyimide or other flexible polymer. In another embodiment, the body is a ceramic, such as AlN or Al2O3. In one embodiment, the body has a disk shape. In one embodiment, the heater assembly 170 is included in the electrostatic chuck 132.

[0028] The primary resistive heater 154 may be provided to raise the temperature of the substrate processing assembly 126 to a temperature for performing a chamber process. The partially adjustable heater 140 is complementary to the primary resistive heater 154 and configured to adjust the local temperature of the electrostatic chuck 132 at multiple discrete locations within one or more of the laterally separated heating zones defined by the primary resistive heater 154. The partially adjustable heater 140 provides local adjustment to the temperature profile of the substrate 134 disposed on the substrate support assembly 126. The primary resistive heater 154 operates on a globalized macroscale, while the partially adjustable heater 140 operates on a localized microscale.

[0029] The primary resistive heater 154 may be coupled to a primary heater power supply 156 via an RF filter 184. The primary heater power supply 156 may provide 900 watts or more of power to the primary resistive heater 154. The controller 148 may control the primary heater power supply 156, which is typically set to heat the substrate 134 to approximately a predetermined temperature. In one embodiment, the primary resistive heater 154 includes laterally separated heating zones, and the controller 148 may preferentially heat one zone of the primary resistive heater 154 compared to primary resistive heaters 154 located in one or more other zones. For example, the primary resistive heater 154 may be arranged concentrically into multiple separated heating zones.

[0030] The partially adjustable heaters 140 may be coupled to an adjustable heater power supply 142 via an RF filter 186. The adjustable heater power supply 142 may provide 10 watts or less of power to the partially adjustable heaters 140. In one embodiment, the power provided by the adjustable heater power supply 142 is an order of magnitude less than the power provided by the main resistive heater power supply 156. Additionally, the partially adjustable heaters 140 may be coupled to an adjustable heater controller 202. The adjustable heater controller 202 may be located internal or external to the substrate support assembly 126. The adjustable heater controller 202 manages the power provided from the adjustable heater power supply 142 to individual adjustable heaters 140 or groups of partially adjustable heaters 140, thereby controlling the heat generated locally at each partially adjustable heater 140 distributed across the substrate support assembly 126. The adjustable heater controller 202 is configured to individually control the power output of one of the partially adjustable heaters 140 relative to the other partially adjustable heaters 140. The optical transducer 178 is coupled to the conditioning heater controller 202 and the controller 148 and can isolate the controller 148 from the effects of RF energy within the processing chamber 100 .

[0031] In one embodiment, the main resistive heater 154 and / or the partially adjustable heaters 140 may be formed within the electrostatic chuck 132. In such an embodiment, the substrate support assembly 126 may be formed with an electrostatic chuck 132 disposed directly on the cooling base 130 without the heater assembly 170. A tunable heater controller 202 may be disposed adjacent to the cooling base and may selectively control the individual partially adjustable heaters 140.

[0032] The electrostatic chuck 132 and / or the heater assembly 170 may include multiple temperature sensors (not shown) for providing temperature feedback information. The temperature feedback information may be sent to the controller 148 to determine the operability of the main resistive heater 154, to control the power applied to the main resistive heater 154 by the main heater power supply 156, to control the operation of the cooling base 130, and / or to control the power applied to the partially adjustable heater 140 by the adjustable heater power supply 142. Alternatively or additionally, the temperature feedback information may be sent to the heater controller 202 to determine the operability of the partially adjustable heater 140 and / or to control the power applied to the partially adjustable heater 140. Each temperature sensor may be located near one of the partially adjustable heaters and may be used to determine the operability of the nearby partially adjustable heater. In one embodiment, each temperature sensor is a resistance temperature detector (RTD). The plurality of temperature sensors may be formed on a plane approximately 0.5-1.0 mm away from the plane on which the plurality of partially adjustable heaters 140 are formed. Thus, in one embodiment, each temperature sensor is separated from the partially adjustable heater by approximately 0.5-1.0 mm. As used herein, the term "proximity" may mean less than 2 mm apart. The material separating the partially adjustable heaters 140 from the temperature sensors may be polyimide, Al2O3, AlN, or other dielectric material.

[0033] The temperature of the surface of the substrate 134 in the processing chamber 100 may be affected by pumping of process gases, the slit valve door, the plasma 122, and / or other factors. The cooling base 130, one or more main resistive heaters 154, and the locally adjustable heater 140 all help control the surface temperature of the substrate 134.

[0034] In a two-zone configuration of the primary resistive heater 154, the primary resistive heater 154 can be used to heat the substrate 134 to a temperature suitable for processing with a variation of approximately ±10°C from one zone to the other. In a four-zone configuration of the primary resistive heater 154, the primary resistive heater 154 can be used to heat the substrate 134 to a temperature suitable for processing with a variation of approximately ±1.5°C within a particular zone. Each zone can vary from approximately 0°C to approximately 20°C from adjacent zones, depending on process conditions and parameters. However, the benefit of minimizing variation in critical dimensions across the substrate is that it reduces the allowable variation in the determined processing temperature of the substrate surface. A 0.5°C change in the surface temperature of the substrate 134 can result in a nanometer-scale difference in the formation of structures therein. The locally adjustable heater 140 improves the temperature profile of the surface of the substrate 134 formed by the primary resistive heater 154 by reducing the variation in the temperature profile to approximately ±0.3°C. The temperature profile can be made uniform across the area of ​​the substrate 134 or can be varied in a precise manner by using locally adjustable heaters 140 .

[0035] 2 is a partial cross-sectional schematic view showing portions of the substrate support assembly 126. FIG. 2 includes portions of the electrostatic chuck 132, the cooling base 130, the heater assembly 170, and the facility plate 180.

[0036] The body 152 of the heater assembly 170 may be fabricated from a polymer (e.g., polyimide, etc.). Thus, in embodiments, the body 152 may be a flexible body. The body 152 may be generally cylindrical, but may be formed in other geometric shapes. The body 152 has an upper surface 270 and a lower surface 272. The upper surface 270 faces the electrostatic chuck 132, and the lower surface 272 faces the cooling base 130.

[0037] The body 152 of the heater assembly 170 may be formed from two or more dielectric layers (four dielectric layers 260, 261, 262, 264 are shown in FIG. 2 ) by heating the layers 260, 261, 262, 264 under pressure into a unitary body 152. For example, the body 152 may be formed from polyimide layers 260, 261, 262, 264, which separate the main resistive heater 154 and the partially adjustable heater 140. The polyimide layers 260, 261, 262, 264 are heated under pressure to form the unitary body 152 of the heater assembly 170. The partially adjustable heater 140 may be disposed in, on, or between the first, second, third, or fourth layers 260, 261, 262, 264 prior to forming the body 152. Furthermore, the main resistive heater 154 may be disposed in, on, or between the first, second, third, or fourth layers 260, 261, 262, 264 prior to assembly, with at least one of the layers 260, 261, 262, 264 separating and electrically insulating the main resistive heater 154 and the partially adjustable heater 140. Furthermore, the temperature sensor 141 may be disposed in, on, or between the first, second, third, or fourth layers 260, 261, 262, 264 prior to assembly, with at least one of the layers 260, 261, 262, 264 separating and electrically insulating the temperature sensor 141 and the partially adjustable heater 140. In this manner, the partially adjustable heater 140, the main resistive heater 154, and the temperature sensor 141 become integral parts of the heater assembly 170.

[0038] In alternative configurations of the location of the main resistive heater 154, the partially adjustable heater 140, and the temperature sensor 141, one or more of the main resistive heater 154, the partially adjustable heater 140, and / or the temperature sensor 141 can be located within or below the electrostatic chuck 132. Figures 3A-3F are partial schematic views of the substrate support assembly 126 detailing various locations of the partially adjustable heater 140, the main resistive heater 154, and the temperature sensor 141.

[0039] 3A , the substrate support assembly 126 does not have a separate heater assembly 170. Instead, the partially adjustable heater 140, the primary resistive heater 154, and the temperature sensor 141 of the heater assembly are located within the electrostatic chuck 132. For example, the primary resistive heater 154, the temperature sensor 141, and the partially adjustable heater 140 may be located below the chucking electrode 136. Although the partially adjustable heater 140 is shown below the primary resistive heater 154 and the temperature sensor 141 is shown below the partially adjustable heater 140, alternative positioning may be used.

[0040] In one embodiment, the electrostatic chuck 132 is formed by stacking multiple Al2O3 or AlN sheets. From top to bottom, the first sheet can have a chucking electrode on its bottom. The second sheet can be bare. The third sheet can have a primary resistive heater 154 thereon. The fourth sheet can be bare. The fifth sheet can have a partially adjustable heater 140 thereon. The sixth sheet can be bare. Holes can be drilled and filled with metal to form vias. The sixth sheet can have a metal layer thereon that acts as a common ground for the partially adjustable heater 154. The metal layer can be connected to the partially adjustable heater 154 by vias. The seventh sheet can be bare. The eighth sheet can have a temperature sensor thereon. The ninth sheet can be bare. Holes can be drilled and filled with metal to form vias. The tenth sheet can have a second metal layer that acts as a common ground for the multiple temperature sensors. The eleventh sheet may be empty. The layers may be heated and compressed in a furnace to form a single monolithic body of AlN or Al2O3, including the electrodes, the main resistive heater 154, the locally adjustable heater 140, the temperature sensor 141, and the metal layer. The electrostatic chuck may then be bonded to a cooling plate using, for example, a silicone bond.

[0041] 3B, the heater assembly 170 for the substrate support assembly 126 includes a partially adjustable heater 140 and a temperature sensor 141, with the primary resistive heater 154 located within (e.g., below the chucking electrode) the electrostatic chuck 132. Alternatively, the partially adjustable heater 140 and the temperature sensor 141 may be located within the electrostatic chuck 132, and the primary resistive heater 154 may be located within the heater assembly 170.

[0042] 3C, the heater assembly 170 for the substrate support assembly 126 has an internally disposed primary resistive heater 154. The locally adjustable heater 140 and temperature sensor 141 are disposed within the electrostatic chuck (e.g., beneath the chuck electrode 136).

[0043] 3D , a heater assembly 170 for the substrate support assembly 126 has a partially adjustable heater 140 and a temperature sensor 141 therein, and a primary resistive heater 154 is deposited on a surface of the heater assembly 170. The heater assembly 170 isolates the partially adjustable heater 140 and the temperature sensor 141 from the cooling base 130. Alternatively, the primary resistive heater 154 and the partially adjustable heater 140 may be disposed within the heater assembly 170, and the temperature sensor 141 is deposited on a surface of the heater assembly 170.

[0044] 3E, the heater assembly 170 of the substrate support assembly 126 has therein a main resistive heater 154 and a partial adjustable heater 140. A temperature sensor 141 is disposed within or on the body of the heater assembly 170 (e.g., below the electrostatic chuck 132).

[0045] 3F, the substrate support assembly 126 does not have a separate heater assembly (170), and the locally adjustable heater 140 and the primary resistive heater 154 are disposed within the electrostatic chuck 132. A temperature sensor 141 is disposed on the bottom surface of the electrostatic chuck 132.

[0046] In another embodiment (not shown), the substrate support assembly 126 does not have a separate heater assembly (170), and the partially adjustable heater 140 and the primary resistive heater 154 are disposed within the electrostatic chuck 132. The temperature sensor 141 is disposed within a temperature sensor assembly including a flexible polymer body having a disk shape or other shape. The flexible polymer body may be polyimide, polyetheretherketone, polyaryletherketone, or the like. The temperature sensor assembly may be disposed on the bottom of the substrate support assembly 126, and each temperature sensor within the temperature sensor assembly may be aligned with the partially adjustable heater 140 and / or the primary resistive heater 154. The temperature sensor assembly may include a ribbon connector having multiple conductive wires, each connecting to a temperature sensor.

[0047] In one embodiment, the electrostatic chuck 132 is formed by stacking multiple sheets of Al2O3 or AlN. From top to bottom, the first sheet can have a chucking electrode on its bottom. The second sheet can be bare. The third sheet can have a main resistive heater 154 thereon. The fourth sheet can be bare. The fifth sheet can have a partially adjustable heater 140 thereon. The sixth sheet can be bare. The sixth sheet can be drilled and filled with metal to form a mesa. The sixth sheet can have a metal layer thereon that acts as a common ground for the partially adjustable heater 154. The metal layer can be connected to the partially adjustable heater 154 by vias. The seventh sheet can be bare. The eighth sheet can have a second metal layer that acts as a common ground for multiple temperature sensors. The ninth sheet can be bare. The ninth sheet can be drilled and filled with metal to form a mesa. The multiple layers can be heated and compressed in a furnace to form a single monolithic body of AlN or Al2O3, including the electrodes, the main resistive heater 154, the locally adjustable heater 140, and the metal layer. A temperature sensor can then be deposited on the bottom of the electrostatic chuck. The temperature sensor can be connected to the second metal layer by a via. The electrostatic chuck can then be bonded to a cooling plate using, for example, a silicone bond.

[0048] It is contemplated that the partially adjustable heater 140, the primary resistive heater 154, and the temperature sensor 141 may be positioned in other arrangements. For example, the substrate support assembly 126 may have multiple partially adjustable heaters 140 for heating the substrate 134, may lack a primary resistive heater 154, and may include a temperature sensor 141 for monitoring the partially adjustable heaters 140. Alternatively, the support assembly 126 may have a primary resistive heater 154 and a temperature sensor 141, but may lack a partially adjustable heater 140. In such an embodiment, the temperature sensor 141 may be positioned in a plane adjacent to the plane containing the primary resistive heater 154. In one embodiment, the partially adjustable heater 140 and the primary resistive heater 154 are positioned directly below each other within the substrate support assembly 126. The partially adjustable heater 140 can provide fine-tuning control of the temperature profile of the substrate 134 supported by the substrate support assembly 126, and the temperature sensor 141 can provide detailed information regarding the operation of the partially adjustable heater 140.

[0049] 3A-3F, one or more conductive planes may be formed in the electrostatic chuck 132 and / or heater assembly 170 and may be used as a common ground for the plurality of temperature sensors 141 and / or the plurality of partially adjustable heaters 141. In one embodiment, a first conductive plane is used as the common ground for the partially adjustable heaters and may be connected to the partially adjustable heaters by vias. In one embodiment, a second conductive plane is used as the common ground for the temperature sensors and may be connected to the temperature sensors by vias. Each of the conductive planes may be a metal layer disposed within the electrostatic chuck or may be a conductive plane disposed within the heater assembly 170.

[0050] Returning to FIG. 2 , the partially adjustable heater 140 may be formed or disposed on or in the body 152 of the heater assembly 170. Alternatively, the partially adjustable heater 140 may be formed or disposed on or within the electrostatic chuck 132. The partially adjustable heater 140 may be formed by plating, inkjet printing, screen printing, physical vapor deposition, stamping, wire mesh, patterned polyimide flex circuitry, or other suitable methods. Vias may be formed in the heater assembly 170 or electrostatic chuck 132 to provide connection from the partially adjustable heater 140 to the heater assembly 170 or the outer surface of the electrostatic chuck 132. Alternatively or additionally, a metal layer (not shown) may be formed in the heater assembly 170 or electrostatic chuck 132. Vias may be formed in the heater assembly 170 or electrostatic chuck 132 to provide connection from the partially adjustable heater 140 to the metal layer. Additional vias may be formed connecting the metal layer to the outer surface of the heater assembly 170 or to the electrostatic chuck 132 .

[0051] In one example, the body 150 of the electrostatic chuck 132 can have vias formed between the partially adjustable heater 140 and the mounting surface 131 of the body 150. In another example, the body 152 of the heater assembly 170 can have vias formed between the partially adjustable heater 140 and an adjacent surface of the body 152 of the cooling base. In another example, the body 150 of the electrostatic chuck 132 can have vias formed between the partially adjustable heater 140 and the metal layer, and between the metal layer and the mounting surface 131 of the body 140. In this manner, manufacturing of the substrate support assembly 126 is simplified.

[0052] Similar to the partially adjustable heaters 140, the temperature sensors 141 may be formed or disposed on or within the body 152 of the heater assembly 170. Alternatively, the temperature sensors 141 may be formed or disposed on or within the electrostatic chuck 132. In one embodiment, the temperature sensors 141 are RTDs. The RTDs may be formed from platinum (Pt), nickel (Ni), nickel-chromium (NiCr), tantalum (Ta), tungsten (W), or other suitable materials. The RTDs may have a thickness of less than one micron to less than a few microns. The resistance coefficient of the RTD may be a function of temperature. Thus, the resistance of the RTD may change based on changes in temperature. The resistance at each RTD can be measured to determine whether a particular partially adjustable heater 140 is operating and / or the temperature of the partially adjustable heater 140. Alternatively, the temperature sensors 141 may be thermocouples. The temperature sensor 141 can be formed by plating, inkjet printing, screen printing, physical vapor deposition, stamping, wire mesh, patterned polyimide flex circuits, or other suitable methods. In one embodiment, the temperature sensor is formed by depositing a metal layer (e.g., platinum), depositing photoresist over the metal layer, patterning the photoresist using a photolithography tool, etching the pattern into the metal layer, and removing the photoresist.

[0053] Vias and / or other connecting wires may be formed in the heater assembly 170 or electrostatic chuck 132 to provide a connection from the temperature sensor 141 to the exterior surface of the heater assembly 170 or electrostatic chuck 132. Alternatively, or additionally, an additional metal layer (not shown) may be formed in the heater assembly 170 or electrostatic chuck 132. Vias may be formed in the heater assembly 170 or electrostatic chuck 132 to provide a connection from the temperature sensor to the additional metal layer. Additional vias may be formed to connect the additional metal layer to the exterior surface of the heater assembly 170 or electrostatic chuck 132. The metal layer connected to the partially adjustable heater 140 may be on a different plane than the additional metal layer connected to the temperature sensor 141. In one embodiment, the vias, other connecting wires, and / or metal layer are copper (Cu), tungsten (W), nickel (Ni), or aluminum (Al).

[0054] In one example, the body 150 of the electrostatic chuck 132 may have a via formed between the temperature sensor 141 and the mounting surface 131 of the body 150. In another example, the body 152 of the heater assembly 170 may have a via formed between the temperature sensor 141 and a portion of the body 152 adjacent to the cooling base 130. In another example, the body 150 of the electrostatic chuck 132 may have vias formed between the temperature sensor 141 and the additional metal layer, and between the additional metal layer and the mounting surface of the body 150. In this manner, manufacturing of the substrate support assembly 126 is simplified.

[0055] In one embodiment, the partially adjustable heater 140 and the temperature sensor 141 are disposed within the heater assembly 170 during formation of the heater assembly 170. In other embodiments, the partially adjustable heater 140 and / or the temperature sensor 141 are disposed directly on the mounting surface 131 of the electrostatic chuck 132. For example, the partially adjustable heater 140 and / or the temperature sensor 141 may be in the form of a sheet that can be adhered to the mounting surface 131 of the electrostatic chuck 132, or the partially adjustable heater 140 and / or the temperature sensor 141 may be deposited by other methods. For example, the partially adjustable heater 140 and / or the temperature sensor 141 may be deposited on the mounting surface 131 by physical vapor deposition, chemical vapor deposition, screen printing, or other suitable methods. The main resistive heater 154 may be within the electrostatic chuck 132 or the heater assembly 170, as described above.

[0056] The primary resistive heater 154 can be formed or disposed on or within the heater assembly 170 or the body of the electrostatic chuck 132. The primary resistive heater 154 can be formed by plating, inkjet printing, screen printing, physical vapor deposition, stamping, wire mesh, or other suitable methods. In this manner, manufacturing of the substrate support assembly 126 is simplified. In one embodiment, the primary resistive heater 154 is disposed within the heater assembly 170 during formation of the heater assembly 170. In other embodiments, the primary resistive heater 154 is disposed directly on the mounting surface of the electrostatic chuck 132. For example, the primary resistive heater 154 can be in the form of a sheet that can be adhered to the mounting surface 131 of the electrostatic chuck 132, or the primary resistive heater 154 can be deposited by other methods. For example, the primary resistive heater 154 can be deposited on the mounting surface 131 by physical vapor deposition, chemical vapor deposition, screen printing, or other suitable methods. The partially adjustable heater 140 may be in the electrostatic chuck 132 or in the heater assembly 170, as indicated above.

[0057] In some embodiments, the main resistive heater 154 is fabricated similarly to the partially adjustable heater 140. In embodiments in which the main resistive heater 154 is fabricated similarly to the partially adjustable heater 140, the main resistive heater can be selectively used without the benefit of an additional partially adjustable heater 140. That is, the main resistive heater 154 of the substrate support assembly 126 is itself partially adjustable, i.e., segmented into multiple individual resistive heating elements. In such embodiments, a separate temperature sensor 141 can be positioned proximate each of the main resistive heaters 154. Segmenting the main resistive heater 154 into smaller resistive heaters allows for localized control of hot and cold spots on the surface of the substrate 134. Depending on the level of temperature control to be implemented, additional layers of partially adjustable heaters 140 can be used.

[0058] The heater assembly 170 may be coupled to the mounting surface 131 of the electrostatic chuck 132 using an adhesive 244. The adhesive 244 may be, for example, an acrylic adhesive, an epoxy, a silicone adhesive, a neoprene adhesive, or other suitable adhesive material. In one embodiment, the adhesive 244 is an epoxy. The adhesive 244 may have a thermal conductivity selected from the range of 0.01 to 200 W / mK, and in one embodiment, 0.1 to 10 W / mK. Additionally, the adhesive material, including the adhesive 244, may include at least one thermally conductive ceramic filler (e.g., aluminum oxide (Al2O3), aluminum nitride (AlN), titanium diboride (TiB2), etc.).

[0059] In one embodiment, heater assembly 170 is coupled to cooling base 130 using adhesive 242. Adhesive 242 may be similar to adhesive 244, such as an acrylic adhesive, an epoxy, a neoprene adhesive, a silicone adhesive, or other suitable adhesive. In one embodiment, bonding agent 242 is an epoxy. Adhesive 242 may have a thermal conductivity coefficient selected from the range of 0.01 to 200 W / mK, and in one embodiment, 0.1 to 10 W / mK. Additionally, bonding materials, including adhesive 244, may include at least one thermally conductive ceramic filler (e.g., aluminum oxide (Al2O3), aluminum nitride (AlN), titanium diboride (TiB2), etc.).

[0060] The adhesives 244, 242 can be removed when modifying one or more of the electrostatic chuck 132, the cooling base 130, and the heater assembly 170. In other embodiments, the heater assembly 170 is removably coupled to the electrostatic chuck 132 and the cooling base 130 using fasteners or clamps (not shown).

[0061] The heater assembly 170 can include multiple partially adjustable heaters 140, illustratively shown as partially adjustable heaters 140A, 140B, 140C, 140D, etc. The partially adjustable heaters 140 are generally enclosed volumes within the heater assembly 170, in which multiple resistive heaters provide thermal transfer between the heater assembly 170 and the electrostatic chuck 132. Each partially adjustable heater 140 can be arranged laterally across the heater assembly 170 to define a cell 200 within the heater assembly 170 and provide additional heat locally to an area of ​​the heater assembly 170 (and a portion of the primary resistive heater 154) aligned with the cell 200. The number of partially adjustable heaters 140 formed within the heater assembly 170 can vary, and it is believed that there will be at least an order of magnitude more partially adjustable heaters 140 (and cells 200) than the number of primary resistive heaters 154. In an embodiment in which the heater assembly 170 has four primary resistive heaters 154, there may be more than 40 partially adjustable heaters 140. However, it is contemplated that in a given embodiment of a substrate support assembly 126 configured for use with a 300 mm substrate, there may be about 200, about 400, or more partially adjustable heaters 140. An exemplary distribution of partially adjustable heaters 140 is further described below with reference to Figures 4A-4D.

[0062] Further, heater assembly 170 can include multiple temperature sensors (e.g., multiple RTDs) 141A, 141B, 141C, 141D, etc. Temperature sensors 141 can be generally enclosed within heater assembly 170. Each temperature sensor 141 can be laterally disposed across heater assembly 170 such that each temperature sensor 141 is within a cell 200 within heater assembly 170 defined by partially adjustable heater 140. In one embodiment, temperature sensor 141 is smaller than partially adjustable heater 140. In one embodiment, each temperature sensor 141 is laterally disposed approximately in the center of a cell 200 defined by partially adjustable heater 140. Each temperature sensor 141 can measure the temperature of the cell 200 in which it is located and / or determine the operability of the partially adjustable heater 140 within that cell 200. Additionally, one or more temperature sensors 141 within a zone defined by a primary resistive heater can be used to measure the temperature of the zone and / or determine the operability of the primary resistive heater 154. A single temperature sensor 141 can be used to determine the operability of both the partially adjustable heater 140 and the primary resistive heater 154.

[0063] The cells 200 can be formed through one or more layers 260, 262, 264 that comprise the body 152 of the heater assembly 170. In one embodiment, the cells are open to the bottom and top surfaces 270, 272 of the body 152. The cells can include sidewalls 214. The sidewalls 214 can be composed of a material (or gap) that acts as a thermal choke 216. The thermal choke 216 can be formed on the top surface 270 of the body 152. The thermal chokes 216 isolate and reduce conduction between adjacent cells 200. Individually and independently controlling the power supplied to each partially tunable heater 140, and therefore the heat conduction through the cells 200, can provide a pixel-by-pixel approach to temperature control, allowing specific points on the substrate 134 to be heated or cooled, enabling true addressable lateral temperature profile adjustment and control of the surface of the substrate 134.

[0064] Additional thermal chokes 216 can be formed between the radially outermost cells 200 and the laterally outermost sidewall 280 of the body 152. The outermost thermal chokes 216 located between the outermost cells 200 and the laterally outermost sidewall 280 of the body 152 minimize heat conduction between the cells 200 adjacent the laterally outermost sidewall 280 and the interior volume 124 of the processing chamber 100. Minimizing heat conduction between the outermost cells 200 and the interior volume 124 allows for more precise temperature control closer to the edge of the substrate support assembly 126, and consequently, better temperature control of the outer diameter edge of the substrate 134.

[0065] Each partially adjustable heater 140 may be independently connected to an adjustable heater controller 202. Additionally, each temperature sensor 141 may be independently connected to an adjustable heater controller 202. In one embodiment, the adjustable heater controller 202 may be located within the substrate support assembly 126. The adjustable heater controller 202 may adjust the temperature of the partially adjustable heaters 140 within the heater assembly 170 in each cell 200 relative to the other cells 200. Alternatively, the adjustable heater controller 202 may adjust the temperature of a group of partially adjustable heaters within the heater assembly 170 across one group of cells 200 relative to the other group of cells 200. The adjustable heater controller 202 may toggle the on / off state and / or control the duty cycle of each partially adjustable heater 140. Alternatively, the adjustable heater controller 202 may control the amount of power supplied to each partially adjustable heater 140. For example, the adjustable heater controller 202 may provide 10 watts of power to one or more partially adjustable heaters 140, 9 watts of power to other partially adjustable heaters 140, and 1 watt of power to yet other partially adjustable heaters 140.

[0066] In one embodiment, the heater controller 202 receives temperature measurements from multiple temperature sensors 141. In one embodiment, the heater controller 202 can receive each temperature measurement as a resistance measurement. The heater controller 202 can then convert the resistance measurements to temperature measurements based on a resistance-temperature conversion model. A separate resistance-temperature conversion model can be used for each temperature sensor. Alternatively, the same resistance-temperature conversion model can be used for multiple temperature sensors. The resistance-temperature conversion model can be formed by performing a calibration of the temperature sensors.

[0067] The heater controller 202 can compare the received temperature measurement of each temperature sensor 141 to the expected temperature measurement of that temperature sensor 141. The expected temperature measurement of a temperature sensor 141 can be based on the set current value of the partially adjustable heater 140 and / or the current set value of the primary resistive heater 154, which are associated with the zone or cell in which the temperature sensor 141 is located. If the delta between the expected temperature measurement and the received temperature measurement of a temperature sensor 141 exceeds a threshold, the heater controller 202 can adjust the duty cycle and / or power of the particular partially adjustable heater 140 associated with the temperature sensor 141. Alternatively or additionally, the heater controller 202 can adjust the duty cycle and / or power of the primary resistive heater associated with the temperature sensor 141. The temperature sensor 141 can be used for feedback control of the partially adjustable heater 140 and / or the primary resistive heater 154.

[0068] In one embodiment, each cell 200 can be thermally isolated from adjacent cells 200, for example, using thermal chokes 216, thereby allowing for more precise temperature control. In other embodiments, each cell 200 can be thermally coupled to adjacent cells, thereby creating an analogous (i.e., smooth or blended) temperature profile along the top surface 270 of the heater assembly 170. For example, a metal layer (e.g., aluminum foil, etc.) can be used as a heat spreader between the main resistive heater 154 and the locally tunable heater 140.

[0069] By using independently controllable partially adjustable heaters 140 to smooth or compensate for the temperature profile produced by the main resistive heater 154, local temperature uniformity across the substrate can be controlled to very tight tolerances, enabling precise process and CD control when processing the substrate. Furthermore, the small size and high density of the partially adjustable heaters 140 relative to the main resistive heater 154 allows temperature control at specific locations on the substrate support assembly 126 without substantially affecting the temperature of adjacent areas. This allows compensation for local hot and cold spots without introducing distortion or other temperature asymmetries. A substrate support assembly 126 with multiple partially adjustable heaters 140 is capable of controlling the temperature uniformity of a substrate 134 processed thereon to better than ±0.3°C.

[0070] Another advantage of some embodiments of the substrate support assembly 126 is the ability to prevent RF power from passing through the control circuitry. For example, the adjustable heater controller 202 can include a power circuit 210 and an optical power controller 220. The power circuit 210 is coupled to the partially adjustable heaters 140. Each partially adjustable heater 140 has a pair of power leads (connectors 250) connected to the power circuit 210. In an exemplary heater assembly 170 having 50 partially adjustable heaters 140, 60 hot and one common power lead (connector 250) can be used to control the partially adjustable heaters 140. RF energy can be supplied to the processing chamber 100 and coupled to the power leads to form a plasma. Filters (e.g., RF filters 182, 184, 186, etc. shown in FIG. 1 ) are used to protect electrical equipment (e.g., the main heater power supply 156, etc.) from the RF energy. By terminating the power leads (connectors 250) at the power circuit 210 and using an optical power controller 220 for each partially adjustable heater 140, a single RF filter 184 can be used between the power circuit 210 and the power supply 156. Instead of each heater having a dedicated RF filter, the partially adjustable heater can use one RF filter, which significantly reduces the number of RF filters used. The space for dedicated RF filters is very limited, and so is the number of heaters used in the substrate support assembly. The number of primary heater zones is unlimited, making it possible to realize a partially adjustable heater. Using the power circuit 210 with the optical power controller 220 allows for more heaters and therefore better lateral temperature control.

[0071] The power circuit 210 can switch or cycle power to multiple connectors 250. The power circuit 210 provides power to each connector 250 to operate one or more partially adjustable heaters 140. Although the power source ultimately powers multiple partially adjustable heaters 140, the power circuit 210 has a single power source, the adjustable heater power supply 142, and uses a single filter 184. Advantageously, the space and cost of additional filters is reduced, and more heaters and heater zones can be used.

[0072] The optical power controller 220 is coupled to the power controller 210 by a fiber optic interface 226 (e.g., a fiber optic cable, etc.), which can control the power provided to the connector 250 and the partially adjustable heater 140. The optical power controller 220 can be coupled to the optical transducer 178 via an optical waveguide 228. The optical transducer 178 is coupled to the controller 148 and provides signals that control the function of the partially adjustable heater 140. The fiber optic interface 226 and the optical waveguide 228 are immune to electromagnetic interference or radio frequency (RF) energy. No RF filters are required to protect the controller 148 from RF energy transmission from the adjustable heater controller 202, which allows more space on the substrate support assembly 126 for routing other utilities.

[0073] The light controller 220 can send commands or instructions to the power circuit 210 to adjust each partially adjustable heater 140 or groups / regions of partially adjustable heaters 140. Each partially adjustable heater 140 can be activated using a combination of positive and negative leads (i.e., connectors) attached to the power circuit 210. Power can flow from the power circuit 210 to the partially adjustable heater 140 via the positive lead and return to the power circuit 210 via the negative lead. In one embodiment, the negative lead is shared among the partially adjustable heaters 140. Each partially adjustable heater 140 has an individual dedicated positive lead, while the partially adjustable heaters 140 can share a common negative lead. In this configuration, the number of connectors 250 from the power circuit 210 to the plurality of partially adjustable heaters 140 is one more than the number of partially adjustable heaters 140. For example, if the substrate support assembly 126 has 100 partially adjustable heaters 140, there are 100 positive leads and 1 negative lead for a total of 101 connectors 250 between the partially adjustable heaters 140 and the power circuit 210. In another embodiment, each partially adjustable heater 140 has a separate negative lead connecting the partially adjustable heater 140 to the power circuit 210. In this configuration, the number of connectors 250 from the power circuit 210 to the partially adjustable heaters 140 is twice the number of partially adjustable heaters 140. For example, if the substrate support assembly 126 has 100 partially adjustable heaters 140, there are 100 positive leads and 100 negative leads for a total of 200 connectors 250 between the partially adjustable heaters and the power circuit 210.

[0074] The optical power controller 220 can be programmed and calibrated by measuring the temperature of each partially adjustable heater 140. The optical controller 220 can control the temperature by adjusting the power parameters of each partially adjustable heater 140. In one embodiment, the temperature can be adjusted by increasing the power to the partially adjustable heater 140. For example, a temperature increase can be achieved by increasing the power supplied to the partially adjustable heater 140 by a factor of (e.g., 9%). In another embodiment, the temperature can be adjusted by cycling the partially adjustable heater 140 on and off. In yet another embodiment, the temperature can be adjusted by a combination of cycling each partially adjustable heater 140 and incrementally adjusting the power to the heater. A temperature map can be obtained using this method. The temperature map can correlate the CD or temperature to the power distribution curve of each partially adjustable heater 140. The partially adjustable heaters 140 can be used to generate a temperature profile based on a program controlling the power settings of the individual partially adjustable heaters. The logic may be located directly within the light controller 220 or may be located directly within an externally connected controller (such as, for example, controller 148).

[0075] The arrangement of the partially adjustable heater 140 and associated temperature sensor 141 will now be described with reference to Figures 4A-4D. Figure 4A is a cross-sectional view taken along section line AA of Figure 2, according to one embodiment. Figures 4B-4D are cross-sectional views taken along the same section line AA of Figure 2, according to an alternative embodiment.

[0076] 4A , a plurality of partially adjustable heaters 140 are disposed along a plane of cross-section line AA through the body 152 of the heater assembly 170. A thermal choke 216 is disposed between each adjacent cell 200, with each cell 200 associated with at least one of the partially adjustable heaters 140. Furthermore, the thermal chokes 216 are disposed along the exterior surface 426 of the substrate support assembly 126. The number of cells 200 shown is for illustrative purposes only; any number of embodiments may have substantially more (or fewer) cells 200. The number of partially adjustable heaters 140 is at least an order of magnitude greater than the number of primary resistive heaters 154. In some embodiments, the number of partially adjustable heaters 140 disposed across the substrate support assembly 126 may exceed several hundred.

[0077] Each partially adjustable heater 140 has a resistor 404 terminating in terminals 406, 408. When current enters one terminal (e.g., the terminal labeled 406) and exits the other terminal (e.g., the terminal labeled 408), the current passes through the wires of the resistor 404 and generates heat. The partially adjustable heater 140 can have a design power density that provides an appropriate temperature rise along the outer surface 426 of the substrate support assembly 126. The amount of heat dissipated by the resistor 404 is proportional to the square of the current passing through it. The power design density can be from about 1 Watt / cell to about 100 Watts / cell (e.g., 10 Watts / cell).

[0078] Resistor 404 may be formed from a film of nichrome, rhenium, tungsten, platinum, tantalum, or other suitable material. Resistor 404 may have an electrical resistivity (ρ). A low ρ indicates a material that readily allows the movement of charge across resistor 404. Resistance (R) depends on ρ times the length (l) across the cross-sectional area (A) of the wire, or simply R=ρ·l / A. Platinum has a resistivity of approximately 1.06×10 at 20°C. -7 Tungsten has a ρ of about 6.60×10-8 (Ω·m) at 20°C. Nichrome has a ρ of about 1.1×10 -8 ~Approx. 1.5×10-8 It has a ρ of Ω·m. Of the three materials mentioned above, resistor 404 made of nichrome transfers charge more easily and generates more heat. However, the electrical properties of tungsten may distinguish it as a resistive heater in certain temperature ranges.

[0079] The resistor 404 can have a film thickness (not shown) and wire thickness 472 configured to efficiently provide heat when a current passes along the resistor 404. Increasing the wire thickness 472 of the resistor 404 can lower the resistance R of the resistor 404. The wire thickness 472 can range from about 0.05 mm to about 0.5 mm for tungsten wire and from about 0.5 mm to about 1 mm for nichrome wire.

[0080] Referring to the equation R=ρ·l / A, the resistor 404 material, wire length, and wire thickness can be selected to control the cost, power consumption, and heat generated by each partially adjustable heater. In one embodiment, the resistor 404 is made of tungsten, which has a wire thickness 472 of approximately 0.08 mm and a resistance of approximately 90 ohms at 10 watts of power.

[0081] The partially adjustable heaters 140 can be arranged in a predetermined pattern 490 to efficiently generate a thermal profile along the surface of the substrate support assembly 126. The pattern 490 may be symmetrical about a center point to provide clearance in or around holes 422 for lift pins or other mechanical, fluid, or electrical connections. Each partially adjustable heater 140 can be controlled by an adjustable heater controller 202. The adjustable heater controller 202 can activate a single partially adjustable heater 140 defining a heater 440, or multiple partially adjustable heaters 140 grouped to define an inner wedge 462, a peripheral group 464, a pie-shaped region 460, or other geometric configurations (including non-contiguous configurations). In this manner, the temperature can be precisely controlled at independent locations along the surface of the substrate support assembly 126, and the independent locations are not limited to concentric rings as known in the art. Although the pattern shown is made up of smaller units, the pattern may alternatively have larger and / or smaller units, may extend to the edges, or may have other forms.

[0082] FIG. 4A also illustrates an RTD 405, which is one type of temperature sensor 141. The RTD 405 is positioned above or below the partially adjustable heater 140. As shown, the RTD 405 is often smaller than the partially adjustable heater 140. The RTD 405 may be a type of resistor that changes resistance based on temperature. In one embodiment, the RTD 405 is platinum wire. Alternatively, the RTD 405 may be any of the other materials described herein. The RTD 405 terminates in terminals 407 and 409. A current is sent through the RTD 405 via the terminals, and the resistance of the RTD 405 is measured, allowing the temperature of the partially adjustable heater 140 to be determined. The RTD 405 material, wire length, and wire thickness can be selected to control the temperature range over which the RTD 405 is sensitive.

[0083] 4B is a top view of multiple partially adjustable heaters 140 arranged along the plane of cross-section line AA through body 152, according to another embodiment. Thermal chokes 216 may optionally be present. The partially adjustable heaters 140 are arranged in the shape of a grid to define an array of temperature-controlled cells 200 arranged in a grid pattern. While the grid pattern of partially adjustable heaters 140 is shown as an X / Y grid of rows and columns, the grid pattern of partially adjustable heaters 140 may alternatively have other uniformly packed shapes (e.g., close-packed hexagons, etc.). As noted above, it should be understood that the partially adjustable heaters 140 may be operated in groups or singly.

[0084] 4C is a top view of multiple partially adjustable heaters 140 arranged along the plane of cross-section line AA through body 152, according to another embodiment. FIG. 4C shows multiple partially adjustable heaters 140 arranged in a circular configuration within body 152. Optionally, one or more thermal chokes 216 may be disposed between the partially adjustable heaters 140. The circular array pattern of partially adjustable heaters 140 also defines adjacent cells 200 arranged in a circular array. Optionally, thermal chokes 216 may be used to separate cells 200 from adjacent cells 200.

[0085] 4D is a top view of multiple partially adjustable heaters 140 arranged along the plane of cross-section line AA through body 152, according to another embodiment. FIG. 4D shows multiple partially adjustable heaters 140 arranged within body 152 in concentric channels. Optionally, the concentric channel pattern of partially adjustable heaters 140 may be separated by thermal chokes 216. It is contemplated that the partially adjustable heaters 140 and cells 200 may be arranged in other orientations.

[0086] The number and density of partially adjustable heaters 140 contribute to the ability to control temperature uniformity across the substrate to very small tolerances, enabling precise process and CD control when processing a substrate 134. Furthermore, the independent control of one partially adjustable heater 140 relative to another partially adjustable heater 140 allows temperature control at specific locations on the substrate support assembly 126 without substantially affecting the temperature of adjacent regions, thereby allowing localized hot and cold spots to be compensated for without introducing distortion or other temperature asymmetries. The partially adjustable heaters 140 can have individual temperature ranges from about 0.0°C to about 10.0°C, with the ability to control the temperature increase in increments of about 0.1°C. In one embodiment, the main resistive heater 154, in conjunction with the multiple partially adjustable heaters 140 in the substrate support assembly 126, is capable of controlling the temperature uniformity of a substrate 134 being processed thereon to better than about ±0.3°C. The partially adjustable heater 140 allows for both lateral and azimuthal adjustment of the lateral temperature profile of the substrate 134 being processed on the substrate support assembly 126 .

[0087] Referring to FIG. 5 , a wiring diagram for the main resistive heater 154 and the partially adjustable heaters 140 is illustrated. The wiring diagram provides individual control, as opposed to multiplexed control, on the partially adjustable heaters 140. Individual control allows for one partially adjustable heater 140, or a selection of multiple partially adjustable heaters 140, to be active simultaneously with another partially adjustable heater 140, or a selection of multiple partially adjustable heaters 140. The wiring diagram allows for individual control of the output of one of the multiple partially adjustable heaters relative to the others of the multiple partially adjustable heaters. The partially adjustable heaters 140 do not have a power source that switches between on and off states, thereby allowing for powering other partially adjustable heaters 140 or selecting multiple partially adjustable heaters 140. Advantageously, this configuration allows for a fast response time in the partially adjustable heaters 140 to achieve a tailored temperature profile.

[0088] The main resistive heater 154 and the partially adjustable heater 140 may be mounted to a control board 502. The control board 502 may be mounted to a power supply 578 via a single RF filter 510. Because each heater 154, 140 shares the single RF filter 510 and does not have its own RF filter, space within the substrate support assembly 126 is conserved and costs associated with additional filters are advantageously mitigated. The control board 502 is similar to the controller 202 shown in FIGS. 1 and 2 and includes similar versions of the electrical controller 210 and the optical controller 220. The control board 502 may be internal or external to the substrate support assembly 126. In one embodiment, the control board 502 is formed between the facility plate 180 and the cooling base 130.

[0089] Partially adjustable heater 140 (1-n) is shown figuratively, it should be understood that the partially adjustable heater 1401 represents multiple partially adjustable heaters in a common zone, or alternatively, represents all partially adjustable heaters 140 distributed across the substrate support assembly 126. In one embodiment, there are an order of magnitude more partially adjustable heaters 140 than main heaters 154, and an order of magnitude more connections to the electrical controller 210 and light controller 220.

[0090] The electrical controller 210 receives a number of connectors 512 from the partially adjustable heater 140 via one or more holes or slots 520 formed through the cooling base 130. The connectors 512 may include any number of connections suitable for coupling between the partially adjustable heater 140 and the electrical controller 210. The connectors 512 may be cables, individual wires, flat flexible cables such as ribbons, mating connectors, or other suitable techniques for transmitting signals between the partially adjustable heater 140 and the electrical controller 210. In one embodiment, the connectors 512 are ribbon cables. The connectors 512 are described using the term power ribbons 512.

[0091] The power ribbons 512 can be connected at one end to the partially adjustable heaters 140 in the ESC 132 and at the other end to the electrical controller 210. The power ribbons 512 can be connected to the electrical controller via direct wiring, sockets, or suitable receptacles. In one embodiment, the electrical controller 210 has sockets configured for high-density connections. The power ribbons 512 can use high-density connectors to provide a large number of connections (e.g., 50 or more connections) from the partially adjustable heaters 140 to the electrical controller 210. The electrical controller 210 can have a high-density interconnect (HDI) that provides a higher wiring density per unit area than conventional printed circuit boards. The HDI can interface with the high-density connectors on the power ribbons 512. Advantageously, the connectors enable high-density connections and facilitate easy assembly and disassembly of the substrate support assembly 126. For example, the ESC 132 may undergo maintenance, resurfacing, or replacement, and the connector provides a quick and easy way to remove the ESC 132 for maintenance and quickly reconnect the ESC 132 to the board support assembly 126.

[0092] Additionally, the electrical controller 210 can receive multiple power ribbons 522 from the main resistive heater 154 via slots 520 formed through the cooling base 130. Power ribbons 512, 522 illustrate multiple power leads for each partially adjustable heater 140 and the main resistive heater 154. For example, power ribbon 512 includes separate positive and negative power leads for each partially adjustable heater 140. Similarly, power ribbon 522 is configured with separate positive and negative power leads for each main resistive heater 154. In one embodiment, each power lead has a switch 560 managed by the optical controller 220. The switch 560 may be located within the electrical controller 210, on the control board 502, or in another suitable location. It is contemplated that a single ribbon or three or more equally spaced ribbons may be used to route the power leads for the partially adjustable heater 140 and the main resistive heater 154. The equally spaced ribbons enhance field uniformity and uniformity of process results.

[0093] The light controller 220 is connected to an external controller (148 in FIG. 1 ) and is configured to provide instructions to the electrical controller to power each of the partially adjustable heaters 140. The light controller 220 accepts multiple control ribbons 540 for managing the partially adjustable heaters 140. In one embodiment, the control ribbon 540 is embedded in the control board 502 and connects the light controller 220 to the electrical controller 210. For example, the control ribbon 540 may be a circuit connecting the two controllers 210, 220. In other embodiments, the control ribbon 540 may connect the light controller 220 to the electrical controller 210 via a cable or other suitable connection external to the control board 502. In yet other embodiments, the control ribbon 540 may pass through slots 520 formed through the cooling base to individually manage each of the partially adjustable heaters 140.

[0094] Optionally, the light controller 220 can accept multiple control ribbons 550 for managing the primary resistive heater 154. Alternatively, the primary resistive heater can be managed by a second light controller or an external controller. Like the control ribbons 540, the control ribbons 550 can be embedded in the control board 502 or attached to the primary resistive heater 154. Alternatively, the primary resistive heater can have no control ribbons 550, and the power cycle and intensity can be managed externally by the power supply 138.

[0095] Ribbons 540, 550 show multiple control leads for each partially adjustable heater 140 and main resistive heater 154. For example, control ribbon 540 includes separate positive and negative control leads for multiple partially adjustable heaters 140. The optical controller 220 can receive input from a program, a temperature measurement device, an external controller, a user, or other source. The optical power controller 220 can determine which partially adjustable heaters 140 and / or main resistive heater 154 to manage. Because the optical controller 220 uses light to communicate with other devices (e.g., the electrical controller 210) outside the RF environment, the optical power controller 220 is not subject to RF interference and does not transmit RF signals to areas outside the process chamber. It is contemplated that a single ribbon, or three or more ribbons, can be used to route the control leads.

[0096] The control ribbon 540 provides a signal generated by the optical controller 220 to control the state of the switch 560. The switch 560 may be a field effect transistor or other suitable electronic switch. Alternatively, the switch 560 may be embedded on an optically controlled circuit board within the electrical controller 210. The switch 560 allows the heaters 154, 140 to be simply cycled between an energized (active) and an unenergized (inactive) state.

[0097] The controller 202 can simultaneously control at least one of the duty cycle, voltage, current, or power duration applied to one or more selected partially adjustable heaters 140 relative to the other partially adjustable heaters 140. In one embodiment, the controller 202 provides a signal along the control ribbon 5401 instructing the switch 5601 to pass 90% power. The electrical controller 210 provides approximately 10 watts of power along the power ribbon 5121. The switch 5601 can pass 90% of the provided power to the partially adjustable heater 140, which heats with approximately 9 watts of power.

[0098] In another embodiment, the controller 202 provides a signal along the control ribbon 5502 instructing the switch 5602 to pass 100% of the power. The electrical controller 210 supplies approximately 100 watts of power along the power ribbon 5222. The switch 5602 allows 100 percent of the supplied power to pass to the primary resistive heater 1542, which heats at approximately 100 watts of power. Similarly, the primary resistive heater 154 (1-N) can all be operated from the controller 202.

[0099] In yet another embodiment, the regulating heater controller 202 provides signals along the control ribbon 540 to instruct the switches 560 to either be in an active state, which allows power to pass, or in an inactive state, which prevents power from passing. The electrical controller 210 provides approximately 10 watts of power along the power ribbon 512 to each partially regulating heater 140 coupled to an active switch 560. The regulating heater controller 202 controls at least one of the duration the switch 560 remains in the active state and the duty cycle of each switch 560 independently of the other switches 560, ultimately controlling the temperature uniformity of the substrate support assembly 126 and the substrates disposed thereon. The switch 560 controlling power to the primary resistive heater 154 can be similarly controlled.

[0100] In other embodiments, each primary resistive heater 154 represents a separate zone. (1-N) Each of the partially adjustable heaters may have a separate controller 202. In this embodiment, the partially adjustable heaters are in common zone with one main resistive heater 154. (1-N) Common main resistance heater 154 (1-N) For example, if there are four zones, there can be four main resistive heaters 154. (1-4) There are four equally spaced controllers 202.

[0101] In other embodiments, separate controllers 202 may be used, dividing up the number of partially adjustable heaters 140 serviced by a single controller. For example, each control ribbon 540 may have a separate light controller 220 for managing each of a set number of partially adjustable heaters 140. By dividing up the control of the partially adjustable heaters 140, the controller may be smaller and require less space to thread the ribbons through the slots 520 formed through the cooling base.

[0102] Referring to FIG. 6, another wiring diagram for the main resistive heater 154 and the partially adjustable heaters 140 is shown. The wiring diagram shown in FIG. 6 provides for individual control of the partially adjustable heaters 140. The partially adjustable heaters 140 are attached to an adjustable heater controller 202. An electrical controller 210 on a control board 502 is attached to a power supply 156 via an RF filter 184. An optical controller 220 is connected to an external controller (148 in FIG. 1) and is configured to instruct the electrical controller to provide power to each partially adjustable heater 140. The optical controller 220 is coupled to the electrical controller 210 via an optical fiber interface 226 to manage the partially adjustable heaters 140. Similar to the wiring diagram of FIG. 5, the wiring diagram of FIG. 6 provides for independent control of the output of one of multiple partially adjustable heaters relative to the other partially adjustable heaters.

[0103] Optionally, the main resistive heater 154 may be attached to the adjustable heater controller 202', the adjustable heater controller 202, or other controller external to the substrate support assembly 126. The adjustable heater controller 202' may be substantially similar to the adjustable heater controller 202. It should be understood that control of the main resistive heater 154 may be similar to that described for the partially adjustable heater 140. Alternatively, the main resistive heater 154 may be externally managed as shown in FIG.

[0104] Partially adjustable heater 140 (1-n) is shown figuratively, and the partially adjustable heater 1401 may represent a large group of partially adjustable heaters in a common zone, or alternatively, may represent all of the partially adjustable heaters 140 distributed across the substrate support assembly 126. Each partially adjustable heater 140 has a connector 250 for transmitting power from the electrical controller 210 to the partially adjustable heater 140.

[0105] The electrical controller 210 receives a plurality of power ribbons 612 from the partially adjustable heaters 140 via one or more holes or slots 520 formed through the cooling base 130. The ribbons 612 show multiple power leads for each partially adjustable heater 140. The power ribbons 612 provide an electrical path for power to the partially adjustable heaters 140. In one embodiment, the power ribbons 612 include individual positive power leads for each partially adjustable heater 140. Optionally, the power ribbons 612 may include a single negative power lead common to all partially adjustable heaters 140 attached to the power ribbon 612. Alternatively, the power ribbons 612 may not have a negative power return path, and the current return path may be provided via a separate cable, a common bus, or other suitable connector. In other embodiments, the power ribbons 612 include separate negative power leads for each partially adjustable heater 140. Optionally, the power ribbon 612 can have a single positive power lead common to all of the partially adjustable heaters 140 attached to the power ribbon 612. Alternatively, the power ribbon 612 may not have a positive power supply path, and the current supply path can be provided via a separate cable, a common bus, or other suitable connector.

[0106] Referring briefly to FIG. 7, FIG. 7 is a perspective view of the bottom 794 of the electrostatic chuck 132 configured for the wiring diagram illustrated in FIG. 6. The electrostatic chuck 132 can have one or more electrodes for applying a chucking force to a substrate disposed on the electrostatic chuck 132 and can have one or more connectors 742 for supplying power to the electrodes. Additionally, the connectors 742 can connect to the primary resistive heaters. In one embodiment, a single connector is used to supply power to a monopolar chucking electrode. In another embodiment, two connectors are used to supply power to a bipolar chucking electrode. In one embodiment, six connectors are used to supply power to four primary resistive heaters. Each primary resistive heater may have a single high-temperature connector or may share a common / ground connector with the other primary resistive heaters. In one embodiment, multiple additional connectors connect to multiple temperature sensors. In one example, there are 150 temperature sensors, each with its own dedicated connector. All temperature sensors can share a single connector providing a common ground. Alternatively, different subsets of temperature sensors may share separate common lines. A number of additional connectors may surround the illustrated connector.

[0107] The power ribbon 612 may be electrically attached to the bottom 794 of the electrostatic chuck 132, within which the partially adjustable heater 140 and / or temperature sensor 141 are formed. The power ribbon 612 may be a flat flexible cable (FFC) or a flexible printed circuit (FPC) (e.g., a polyimide flat flexible cable, etc.) having a connector 712 on one end and contacts 720 on the other end. The connector 712 connects to the electrical controller 210. The connector 712 may be individual wires, a socket connector, a plug, a high-density connector (e.g., one used in flat flexible cables or flexible printed circuits), or other suitable connector. The contacts 720 may be attached to electrical connections (i.e., vias) formed in the electrostatic chuck 132. The contacts 720 may be soldered, glued, or otherwise attached to the electrostatic chuck 132. Alternatively, the contacts 720 may be formed directly connected to the partially adjustable heater 140 (e.g., wired power leads, etc.). The contacts 720 may have a bonded area (less than a circle with a diameter of about 0.75 inches) that contacts the electrostatic chuck 132. This minimal area that the contacts 720 have with the electrostatic chuck 132 reduces heat conduction from the electrostatic chuck 132 to the cooling base 130. The contacts 720 may be circular, rectangular, semicircular, or other shapes. A power ribbon 612 may have two or more contacts 720 and 100 or more leads. A single power ribbon 612 can connect to and individually control multiple partially adjustable heaters 140 depending on the wiring configuration to the electrical controller 210 (e.g., sharing a common negative lead). Additionally, the power ribbon 612 may be used to connect to temperature sensors. In one embodiment, the electrostatic chuck 132 has six equally spaced, soldered power ribbons 612. Each power ribbon 612 may have 25 soldered contacts 720. Alternatively, the electrostatic chuck 132 can have more or fewer power ribbons 612 .

[0108] Alternatively, the power ribbons 612 can be replaced with pin / receptacle connectors. Briefly referring to FIG. 10 , FIG. 10 shows a cross-sectional view of a mating connector 1010 that connects the ESC 132 to the regulating heater controller 202. The mating connector 1010 can be sized to pass through a slot 520 in the cooling base 130 to provide a connection between the regulating heater controller 202 and the ESC. The mating connector 1010 can have a flange 1008. The flange 1008 can be disposed between the cooling base 130 and the regulating heater controller 202. A gap 1050 can be formed between the cooling base 130 and the regulating heater controller. Alternatively, the regulating heater controller 202 can have a notch, hole, void, or other opening that allows the mating connector 1010 to pass through and substantially reduce the gap 1050 between the regulating heater controller 202 and the cooling base 130.

[0109] The mating connector 1010 can have a first end 1002 and a second end 1004. The first end 1002 can interface with the ESC 132. The second end 1004 can be the regulating heater controller 202. A plurality of contact pins 1012, 1014 interface with a plurality of pin receptacles 1020, 1022 to provide an electrical connection between the ESC 132 and the regulating heater controller 202. The pins 1012, 1014 can be approximately 0.3 mm or less. The pins 1012, 1014 have corresponding plurality of pin receptacles 1020, 1022 configured to receive the pins 1012, 1014 and provide electrical continuity. Pins 1012 , 1014 or pin receptacles 1020 , 1022 may be formed on one or more of the first and second ends 1002 , 1004 of the mating connector 1010 to interface between the ESC 132 and the regulating heater controller 202 .

[0110] The mating connector 1010 can provide a direct physical and electrical connection between the regulating heater controller 202 and the ESC 132. For example, a receptacle can be formed on the regulating heater controller 202 that accepts the pin 1014. The cooling base 130 can be placed directly on the ESC, the mating connector 1010 inserted through the slot 520 in the cooling base 130, and the regulating heater controller 202 placed on the mating connector 1010 to form the connection between the ESC 132 and the regulating heater controller 202. Alternatively, the mating connector 1010 can use a cable, ribbon, or flat connector to complete the connection between the regulating heater controller 202 and the ESC 132.

[0111] Advantageously, the mating connector 1010 can have a small cross-sectional area and correspondingly use little open area of ​​the cooling base 130, minimizing thermal conductance or obstruction of the cooling base 130 for better thermal uniformity. Additionally, the mating connector 1010 can protect the connection from the processing environment, extending the life of the electrical connection.

[0112] 6, electrical controller 210 has a plurality of switches 660 formed therein. Each switch 660 receives a positive power lead from one of power ribbons 612 and can control an individual partially adjustable heater 140. Optical controller 220 manages switches 660 via an electrical controller through fiber optic interface 226. Circuitry 640 can be embedded within electrical controller 210 or adjustable heater controller 202 and can convert optical signals to electrical signals for instructions to be provided to switches 660.

[0113] The switch 660 may be a field effect transistor or other suitable electronic switch that can easily cycle the heater 154, 140 between an energized (active) and an unenergized (inactive) state. Alternatively, the switch 660 may be any other suitable device that can control the amount of power delivered to the partially adjustable heater 140.

[0114] The switch 660 may be formed internally to the substrate support assembly 126 (e.g., internally to the electrostatic chuck 132, the cooling base 130, the heater assembly 170, and the facility plate 180, etc.) Alternatively, the switch 660 may be formed externally to the substrate support assembly 126 or the controller 148 (e.g., within the controller 148).

[0115] Referring to FIG. 8 , FIG. 8 shows a bottom perspective view of the cooling base 130 configured for the wiring diagram depicted in FIG. 6 . The cooling base 130 may have a bottom surface 894, a plurality of cooling passages (not shown in FIG. 8 ), and a passage 842. The cooling passages are configured to circulate a cooling fluid to control the temperature of the electrostatic chuck 132. The electrostatic passage 842 may be configured to allow an electrode 742 that supplies power to the electrostatic chuck 132 to pass through the cooling base 130. The passage 842 is electrically insulated and provides protection from the electrode 742 that supplies energy to the cooling base 130. Additionally, the cooling base 130 may have one or more slots 520. The slots 520 may be configured to allow the ribbon 612 to pass from the electrostatic chuck 132 through the interior of the cooling base 130 and into the interior of the bottom surface 894.

[0116] The electrical controller 210 may be disposed on the bottom surface 894 of the cooling base 130. The electrical controller 210 is disposed in an RF environment, and communication with the electrical controller 210 may be via optical fiber, while power to the electrical controller 210 may be provided via an RF filter. The electrical controller 210 may have a transmitter 826 and a receiver 828, and an optical fiber interface 226. The optical fiber interface 226 provides an optical connection to the optical controller 220. The optical fiber interface 226 is immune to RF and other electrical interference and does not use filters to protect the connected devices / controllers (e.g., the optical controller 220, etc.).

[0117] The adjustable heater controller 202 may have a plurality of sockets 812. The sockets 812 may be configured to mate with connectors 712 attached to the ends of the ribbons 612. The sockets may provide 50 or more individual connections to each ribbon 612. The electrical controller 210 may be comprised of a substrate 830 and a plurality of circuits 832, 834 formed thereon. The plurality of circuits 832, 834 may include transistors, resistors, capacitors, and other electrical features to form switches and control the flow of power to individual connections in the sockets 812. The electrical controller 210 manages the individual partially adjustable heaters 140 by controlling at least one or more of the duty cycle, voltage, current, or duration of power supplied to individual connections in the sockets 812 attached to the ribbons 612.

[0118] Additionally, heater controller 202 may include one or more temperature measurement circuits (not shown) for measuring temperature from readings generated by the plurality of temperature sensors 141. The temperature measurement circuits may provide temperature measurements associated with the partially adjustable heaters and / or the main resistive heater to electrical controller 210. Electrical controller 210 may then determine whether to adjust the duty cycle, voltage, etc. of the associated partially adjustable heaters.

[0119] In one embodiment, the switch 660 is formed on the electrical controller 210. A ribbon 612 with connectors 712 passes through slots 520 in the cooling base 130 and connects the partially adjustable heaters 140 in the electrostatic chuck 132 to the electrical controller 210. The connectors 712 connect the ribbon 612 to sockets 812 on the electrical controller 210. The optical controller 220 provides optical signals to the electrical controller 210 via the fiber optic interface 226 to control power to individual connections in the sockets 812. The combination of the optical controller 220 and the electrical controller 210 allows for selection of individual partially adjustable heaters 140 to be simultaneously powered and / or cycled on and off to create a tailored temperature profile on a substrate disposed on the electrostatic chuck 132. The use of dense interconnects allows for individual control of a large number of partially adjustable heaters 140 and enhanced control of the temperature profile. Advantageously, independent control of the partially adjustable heaters 140 allows for a higher duty cycle and a larger dynamic temperature range for each individual partially adjustable heater 140. Individual control of the partially adjustable heaters 140 provides higher power per unit time with a faster response time.

[0120] 9 is a flow diagram of one embodiment of a method 900 for processing a substrate using a substrate support assembly (such as the substrate support assemblies described above, among others). The method 900 begins at block 902 by applying power to a primary resistive heater formed in the substrate support assembly. The primary resistive heater may be a single heater or may be divided into zones. The primary resistive heater zones may be independently controllable.

[0121] In block 904, power is supplied to a plurality of individual partially adjustable heaters distributed around the substrate support assembly. A variable heater controller individually controls the power to each of the partially adjustable heaters. At least two of the partially adjustable heaters generate different predetermined amounts of heat. The difference in heat generated by one partially adjustable heater relative to the other heaters can be controlled by controlling at least one or more of the duty cycle, voltage, current, and duration of power applied to one partially adjustable heater relative to the other heaters. The power supplied to the partially adjustable heaters can be scanned sequentially across the individual partially adjustable heaters.

[0122] Control of each partially adjustable heater can be performed simultaneously within the electrostatic chuck 132, thereby enabling selection of the partially adjustable heaters to rapidly generate specific temperature profiles. Control of the power supplied to each partially adjustable heater can be provided to an adjustable heater controller located on the substrate support assembly via an external controller interfaced by an optical connection. The external controller is RF isolated by the optical connection to the adjustable heater controller.

[0123] In block 906, a workpiece (e.g., a substrate, etc.) can be processed on the substrate support assembly. For example, the substrate can be processed in a vacuum chamber, for example, using a plasma process. The vacuum process that can be additionally performed in the presence of a plasma in the processing chamber can be one of etching, chemical vapor deposition, physical vapor deposition, ion implantation process, plasma treatment, annealing, oxide removal, abatement, or other plasma treatment process. It is contemplated that the workpiece can be processed for other applications on a temperature-controlled surface in a different environment (e.g., under atmospheric conditions).

[0124] Optionally, in block 906, the power supplied to individual partially adjustable heaters laterally distributed within the substrate support assembly may be varied in response to changes in process conditions or process recipes. For example, the power supplied to one or more partially adjustable heaters may be varied using commands from a tunable heater controller. The tunable heater controller may simultaneously supply power to one partially adjustable heater while cycling other partially adjustable heaters and further cycling yet other partially adjustable heaters with different overlapping time intervals.

[0125] While the foregoing is directed to embodiments of the present invention, other and further embodiments may be made without departing from the basic scope of the invention, which scope is defined by the following claims.

Claims

1. 1. A substrate support assembly comprising a plurality of zones, a chuck including a ceramic body; an additional assembly coupled to the underside of the chuck, a second body; and an additional assembly including a plurality of temperature sensors disposed in or on the second body, each of the plurality of zones including at least one of the plurality of temperature sensors for measuring the temperature of the respective zone; a plurality of primary resistive heating elements disposed a) within or on the ceramic body, or b) within or on the second body, each primary resistive heating element being disposed in a different one of a plurality of zones; a) a plurality of spatially adjustable heating elements disposed within or on the ceramic body, or b) a second body, each of the plurality of zones comprising at least one of the plurality of spatially adjustable heating elements and heated by the spatially adjustable heating elements disposed within each zone, the plurality of spatially adjustable heating elements being controlled in accordance with temperature measurements by a plurality of temperature sensors in each zone, and the power supplied to the spatially adjustable heating elements being an order of magnitude less than the power supplied to the primary resistive heating element; a metal layer within the ceramic body or the second body, the metal layer a) being separated from one or more spatially adjustable heating elements of the plurality of spatially adjustable heating elements and serving as a common ground for the one or more spatially adjustable heating elements, or b) being separated from one or more temperature sensors of the plurality of temperature sensors and serving as a common ground for the one or more temperature sensors; A substrate support assembly including a plurality of vias connecting the metal layer to one or more spatially adjustable heating elements or one or more temperature sensors.

2. 1. A substrate support assembly comprising a plurality of zones, a chuck including a ceramic body; an additional assembly coupled to the underside of the chuck, a second body; and an additional assembly including a plurality of temperature sensors disposed in or on the second body, each of the plurality of zones including at least one of the plurality of temperature sensors for measuring the temperature of the respective zone; a plurality of primary resistive heating elements disposed a) within or on the ceramic body, or b) within or on the second body, each primary resistive heating element being disposed in a different one of a plurality of zones; a) a plurality of spatially adjustable heating elements disposed within or on the ceramic body, or b) a second body, each of the plurality of zones comprising at least one of the plurality of spatially adjustable heating elements and heated by the spatially adjustable heating elements disposed within each zone, the plurality of spatially adjustable heating elements being controlled in accordance with temperature measurements by a plurality of temperature sensors in each zone, and the power supplied to the spatially adjustable heating elements being an order of magnitude less than the power supplied to the primary resistive heating element; a heater controller electrically connected to one or more of the plurality of spatially adjustable heating elements, the heater controller performing at least one of a first set of operations or a second set of operations, the first set of operations including: Independently controlling the power of a first spatially adjustable heating element of the plurality of spatially adjustable heating elements relative to a second spatially adjustable heating element of the plurality of spatially adjustable heating elements; receiving a temperature measurement from a first temperature sensor of the plurality of temperature sensors proximate to the first spatially adjustable heating element; determining whether the first spatially adjustable heating element has failed based on the temperature measurements; The second set of operations includes receiving a temperature measurement from a first temperature sensor of the plurality of temperature sensors proximate to the first spatially adjustable heating element; determining a difference between the temperature measurement and the temperature setting of the first spatially adjustable heating element; determining whether the difference exceeds a threshold; The substrate support assembly includes adjusting a setting of the first spatially adjustable heating element in response to determining that the difference exceeds a threshold value.

3. 3. The substrate support assembly of claim 1, wherein the additional assembly includes a plurality of main resistive heating elements disposed in or on the second body, each of the plurality of main resistive heating elements being disposed in a different one of the plurality of zones.

4. a) a plurality of temperature sensors disposed on the second body, a plurality of primary resistive heating elements disposed on the second body, and a plurality of spatially adjustable heating elements disposed on a surface of the second body; b) a plurality of temperature sensors are disposed on a surface of the second body, a plurality of primary resistive heating elements are disposed on the second body, and a plurality of spatially adjustable heating elements are disposed on the second body; or c) a plurality of temperature sensors disposed on the second body, a plurality of primary resistive heating elements disposed on the second body, and a plurality of spatially adjustable heating elements disposed on the second body; The substrate support assembly of claim 3 , wherein any one of the following is true:

5. The substrate support assembly of claim 1 or 2, wherein the second body is a flexible body comprising polyimide.

6. The substrate support assembly of claim 1 or 2, wherein one or more of the plurality of temperature sensors comprises a resistance temperature detector (RTD) or a thermocouple.

7. 3. The substrate support assembly of claim 1, wherein the chuck includes a plurality of primary resistive heating elements disposed within or on the ceramic body, each primary resistive heating element of the plurality of primary resistive heating elements being disposed in a different one of the plurality of zones.

8. 3. The substrate support assembly of claim 1, wherein the plurality of spatially adjustable heating elements are formed on a first plane and the plurality of temperature sensors are formed on a second plane, the second plane being separated from the first plane by about 0.5 to 1.0 mm.

9. 1. A substrate support assembly comprising a plurality of zones, a chuck including a ceramic body; a plurality of primary resistive heating elements disposed within or on the ceramic body, each primary resistive heating element being disposed in a different one of the plurality of zones; a plurality of spatially adjustable heating elements disposed in the ceramic body on a first plane, each of the plurality of zones including at least one of the plurality of spatially adjustable heating elements, the heating elements being heated by the spatially adjustable heating elements disposed in each zone, the power supplied to the spatially adjustable heating elements being an order of magnitude less than the power supplied to the primary resistive heating element; a plurality of temperature sensors disposed in at least one of 1) within the ceramic body or 2) on a bottom surface of the ceramic body, the plurality of temperature sensors being disposed on a second plane, each of the plurality of zones including at least one of the plurality of temperature sensors measuring a temperature of each zone to control a spatially adjustable heating element in each zone; a metal layer within the ceramic body or the second body, the metal layer a) being separated from one or more spatially adjustable heating elements of the plurality of spatially adjustable heating elements and serving as a common ground for the one or more spatially adjustable heating elements, or b) being separated from one or more temperature sensors of the plurality of temperature sensors and serving as a common ground for the one or more temperature sensors; A substrate support assembly including a plurality of vias connecting the metal layer to one or more spatially adjustable heating elements or one or more temperature sensors.

10. 1. A substrate support assembly comprising a plurality of zones, a chuck including a ceramic body; a plurality of primary resistive heating elements disposed within or on the ceramic body, each primary resistive heating element being disposed in a different one of the plurality of zones; a plurality of spatially adjustable heating elements disposed in the ceramic body on a first plane, each of the plurality of zones including at least one of the plurality of spatially adjustable heating elements, wherein the power supplied to the spatially adjustable heating elements is an order of magnitude less than the power supplied to the primary resistive heating element; a plurality of temperature sensors disposed in at least one of 1) within the ceramic body or 2) on a bottom surface of the ceramic body, the plurality of temperature sensors being disposed on a second plane, each of the plurality of zones including at least one of the plurality of temperature sensors measuring a temperature of each zone to control a spatially adjustable heating element in each zone; a heater controller electrically connected to a first spatially adjustable heating element of the plurality of spatially adjustable heating elements, receiving a temperature measurement from a first temperature sensor of the plurality of temperature sensors proximate to the first spatially adjustable heating element; determining a difference between the temperature measurement and the temperature setting of the first spatially adjustable heating element; determining whether the difference exceeds a threshold; A substrate support assembly comprising a heater controller that adjusts a setting of the first spatially adjustable heating element in response to determining that the difference exceeds a threshold value.

11. 11. The substrate support assembly of claim 9 or 10, wherein a plurality of primary resistive heating elements are disposed within or on the ceramic body, each primary resistive heating element of the plurality of primary resistive heating elements being disposed in a different one of the plurality of zones.

12. The substrate support assembly of claim 9 or 10, wherein the plurality of temperature sensors comprises a plurality of resistance temperature detectors (RTDs) or a plurality of thermocouples.

13. an additional assembly coupled to the underside of the chuck, a second body; and 11. The substrate support assembly of claim 9 or 10, wherein a plurality of primary resistive heating elements are disposed within or on the second body, each primary resistive heating element of the plurality of primary resistive heating elements being disposed in a different one of the plurality of zones.

14. The substrate support assembly of claim 13 , wherein the second body is a flexible body comprising polyimide.

15. The substrate support assembly of claim 9 or 10, wherein the second plane is separated from the first plane by about 0.5 to 1.0 mm.

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