Designs for metallic straps connecting diodes and heaters embedded in electrostatic chucks

Abstract

A substrate support includes a semiconductor switching device that supplies power to a heating element arranged in an insulating layer of the substrate support and a metallic strap that connects the semiconductor switching device to the heating element. The metallic strap includes a first segment, a first plurality of segments, a second segment, and a second plurality of segments. The first segment extends from a first end of the metallic strap and extends away from the insulating layer at an acute angle relative to a plane of the insulating layer. The first plurality of segments includes a series of angular structures with a first end connected to the first segment. The second segment extends from a second end of the first plurality of segments. The second plurality of segments extends from the second segment to the second end of the metallic strap connected to the heating element.

Description

DESIGNS FOR METALLIC STRAPS CONNECTING DIODES AND HEATERS EMBEDDED IN ELECTROSTATIC CHUCKSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 551 ,469, filed on February 8, 2024. The entire disclosure of the application referenced above is incorporated herein by reference.FIELD

[0002] The present disclosure relates generally to plasma processing chambers and more particularly to designs for metallic straps connecting diodes and heaters embedded in electrostatic chucks.BACKGROUND

[0003] The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

[0004] Substrate processing systems may be used to perform etching, deposition, and / or other treatment of substrates such as semiconductor wafers. Examples of processes that may be performed on a substrate include, but are not limited to, chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), atomic layer deposition (ALD), atomic layer etch (ALE), plasma enhanced atomic layer deposition (PEALD) and / or other etch, deposition, and cleaning processes. During processing, a substrate is arranged on a substrate support, such as a pedestal, an electrostatic chuck (ESC), etc. in a processing chamber of the substrate processing system. A process gas mixture is introduced into the processing chamber to treat the substrate. In some examples, plasma may be struck to enhance chemical reactions within the processing chamber.SUMMARY

[0005] A substrate support comprises a semiconductor switching device and a metallic strap. The semiconductor switching device is arranged in an insulating layer of thesubstrate support. The semiconductor switching device is configured to supply power to a heating element arranged in the insulating layer of the substrate support. The metallic strap connects the semiconductor switching device to the heating element. A first end of the metallic strap is connected to the semiconductor switching device by an electrically conducting material. A second end of the metallic strap is connected to the heating element by the electrically conducting material. The metallic strap comprises a first segment, a first plurality of segments, a second segment, and a second plurality of segments. The first segment extends from the first end of the metallic strap and extends away from the insulating layer of the substrate support at an acute angle relative to a plane of the insulating layer. The first plurality of segments comprise a series of angular structures with a first end of the first plurality of segments connected to the first segment. The second segment extends from a second end of the first plurality of segments. The second plurality of segments extends from the second segment to the second end of the metallic strap connected to the heating element.

[0006] In additional features, the series of angular structures have a shape of the letter “M” or the letter “W.”

[0007] In additional features, the acute angle is between 25 and 45 degrees.

[0008] In additional features, the acute angle is between 15 and 25 degrees.

[0009] In additional features, the second segment extends parallel to the plane of the insulating layer.

[0010] In additional features, the second segment is straight.

[0011] In additional features, the second segment is wave shaped.

[0012] In additional features, the wave shape is sinusoidal.

[0013] In additional features, the metallic strap has a uniform thickness and width.

[0014] In additional features, the metallic strap is unitary.

[0015] In additional features, at least one of a thickness and a width of the second segment is less than a thickness and less than a width of the rest of the metallic strap.

[0016] In additional features, at least one of a thickness and a width of the second segment is less than half of a thickness and less than half of a width of the rest of the metallic strap.

[0017] In additional features, at least one of the first plurality of segments and at least one of the second plurality of segments extend away from the plane of the insulating layer at an angle.

[0018] In additional features, at least one of the first plurality of segments and at least one of the second plurality of segments extend towards the plane of the insulating layer at an angle.

[0019] In still other features, a substrate support comprises a semiconductor switching device and a metallic strap. The semiconductor switching device is arranged in an insulating layer of the substrate support. The semiconductor switching device is configured to supply power to a heating element arranged in the insulating layer of the substrate support. The metallic strap connects the semiconductor switching device to the heating element. A first end of the metallic strap is connected to the semiconductor switching device by an electrically conducting material. A second end of the metallic strap is connected to the heating element by the electrically conducting material. The metallic strap comprises a first segment, a first plurality of segments, a second segment, and a second plurality of segments. The first segment extends from the first end of the metallic strap and extends away from the insulating layer of the substrate support at an acute angle relative to a plane of the insulating layer. The first plurality of segments has a first end connected to the first segment. The second segment extends from a second end of the first plurality of segments. The second segment is wave shaped. At least one of a thickness and a width of the second segment is less than a thickness and less than a width of the rest of the metallic strap. The second plurality of segments extends from the second segment to the second end of the metallic strap connected to the heating element.

[0020] In additional features, at least one of a thickness and a width of the second segment is less than half of a thickness and less than half of a width of the rest of the metallic strap.

[0021] In additional features, the wave shape is sinusoidal.

[0022] In additional features, the acute angle is between 25 and 45 degrees.

[0023] In additional features, the acute angle is between 15 and 25 degrees.

[0024] In additional features, the second segment extends parallel to the plane of the insulating layer.

[0025] In additional features, the rest of the metallic strap has a uniform thickness and width.

[0026] In additional features, the metallic strap is unitary.

[0027] In additional features, at least one of the first plurality of segments and at least one of the second plurality of segments extend away from the plane of the insulating layer at an angle.

[0028] In additional features, at least one of the first plurality of segments and at least one of the second plurality of segments extend towards the plane of the insulating layer at an angle.

[0029] In still other features, a substrate support comprises a semiconductor switching device and a metallic strap. The semiconductor switching device is arranged in an insulating layer of the substrate support. The semiconductor switching device is configured to supply power to a heating element arranged in the insulating layer of the substrate support. The metallic strap connects the semiconductor switching device to the heating element. A first end of the metallic strap is connected to the semiconductor switching device by an electrically conducting material. A second end of the metallic strap is connected to the heating element by the electrically conducting material. The metallic strap comprises a first segment, a first plurality of segments, a second segment, and a second plurality of segments. The first segment extends from the first end of the metallic strap and extends away from the insulating layer of the substrate support at an angle between 15 and 25 degrees relative to a plane of the insulating layer. The first plurality of segments has a first end connected to the first segment. The second segment extends from a second end of the first plurality of segments. The second plurality of segments extends from the second segment to the second end of the metallic strap connected to the heating element.

[0030] In additional features, the second segment extends parallel to the plane of the insulating layer.

[0031] In additional features, the second segment is straight.

[0032] In additional features, the second segment is wave shaped.

[0033] In additional features, the wave shape is sinusoidal.

[0034] In additional features, the metallic strap has a uniform thickness and width.

[0035] In additional features, the metallic strap is unitary.

[0036] In additional features, at least one of the first plurality of segments and at least one of the second plurality of segments extend away from the plane of the insulating layer.

[0037] In additional features, at least one of the first plurality of segments and at least one of the second plurality of segments extend towards the plane of the insulating layer.

[0038] Further areas of applicability of the present disclosure will become apparent from the detailed description, the claims and the drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

[0040] FIG. 1 shows an example of a substrate processing system;

[0041] FIG. 2 shows a simplified example of a substrate support such as an electrostatic chuck (ESC) used to support substrates during processing in the plasma chamber of FIG. 1 ;

[0042] FIG. 3 shows the substrate support of FIG. 2 in further detail;

[0043] FIG. 4 shows a schematic representation of a heater matrix comprising heater elements and diodes used in the substrate support of FIG. 3;

[0044] FIG. 5 shows an expanded view of a portion of FIG.3, showing one of the diodes in further detail;

[0045] FIG. 6 shows a view of FIG. 5 rotated (inverted) by 180 degrees around a vertical axis;

[0046] FIG. 7A shows a first design of a metallic strap for connecting diodes and heaters embedded in the substrate support of FIG. 2 according to the present disclosure;

[0047] FIG. 7B shows a top view of the metallic strap of 7A;

[0048] FIG. 8 shows a second design of a metallic strap for connecting diodes and heaters embedded in the substrate support of FIG. 2 according to the present disclosure;

[0049] FIG. 9A shows a third design of a metallic strap for connecting diodes and heaters embedded in the substrate support of FIG. 2 according to the present disclosure;

[0050] FIG. 9B shows a top view of the metallic strap of FIG. 9A;

[0051] FIG. 10 shows a fourth design of a metallic strap for connecting diodes and heaters embedded in the substrate support of FIG. 2 according to the present disclosure;

[0052] FIG. 1 1 shows a fifth design of a metallic strap for connecting diodes and heaters embedded in the substrate support of FIG. 2 according to the present disclosure;

[0053] FIG. 12 shows a sixth design of a metallic strap for connecting diodes and heaters embedded in the substrate support of FIG. 2 according to the present disclosure;

[0054] FIG. 13A shows a seventh design of a metallic strap for connecting diodes and heaters embedded in the substrate support of FIG. 2 according to the present disclosure; and

[0055] FIG. 13B shows a top view of the metallic strap of FIG. 13A.

[0056] In the drawings, reference numbers may be reused to identify similar and / or identical elements.DETAILED DESCRIPTION

[0057] As explained below in detail, multiple heater elements can be arranged in an electrostatic chuck (ESC) of a plasma chamber to control temperature profiles of substrates such as semiconductor wafers during processing in the plasma chamber. Diodes can be connected in series with the heater elements by metallic straps to enable independent control of the heater elements. The heater elements and the diodes can be embedded in the ESC. In some processes, the diodes and the metallic straps can be subjected to high temperatures that can cause the diodes and / or metallic straps to fail, which can destroy the ability to individually control the heater elements and which can also require replacing the ESC. Losing the ability to individually control the heater elements can degrade substrate performance. Replacing the ESC can be expensive and can increase system downtime. The present disclosure relates to various novel designs of metallic straps that can withstand high temperatures.

[0058] The present disclosure is organized as follows. An example of a substrate processing system is shown and described with reference to FIG. 1. An ESC with embedded heater elements and diodes is shown and described with reference to FIGS.2 and 3. A schematic of an array comprising heater elements and diodes used in the ESC is shown and described with reference to FIG. 4. An example of a diodes embedded in the ESC is shown and described with reference to FIG. 5. Failures of the diodes that can occur at high temperatures are discussed with reference to FIG. 6. Subsequently, thermal issues with the metallic straps used to connect the diodes and the heater elements are described. Thereafter, various novel designs of metallic straps for connecting diodes and heaters embedded in electrostatic chucks are shown and described with reference to FIGS. 7A-13B.EXAMPLE OF SUBSTRATE PROCESSING SYSTEM

[0059] FIG. 1 shows an example of a substrate processing system 100. For example only, the substrate processing system 100 may be used for performing etching using RF plasma and / or other suitable substrate processing. The substrate processing system 100 includes a processing chamber 102 that encloses other components of the substrate processing system 100 and contains the RF plasma. The substrate processing chamber 102 includes an upper electrode 104 and a substrate support 106, such as an electrostatic chuck (ESC). During operation, a substrate 108 is arranged on the substrate support 106. While a specific substrate processing system 100 and processing chamber 102 are shown as an example, the principles of the present disclosure may be applied to other types of substrate processing systems and chambers, such as a substrate processing system that generates plasma in-situ, that implements remote plasma generation and delivery (e.g., using a plasma tube, a microwave tube), etc.

[0060] For example only, the upper electrode 104 may include a gas distribution device such as a showerhead 109 that introduces and distributes process gases. The showerhead 109 may include a stem portion including one end connected to a top surface of the processing chamber. A base portion is generally cylindrical and extends radially outwardly from an opposite end of the stem portion at a location that is spaced from the top surface of the processing chamber. A substrate-facing surface or faceplate of the base portion of the showerhead includes a plurality of holes through which process gas or purge gas flows. Alternately, the upper electrode 104 may include a conducting plate and the process gases may be introduced in another manner.

[0061] The substrate support 106 includes a conductive baseplate 1 10 that acts as a lower electrode. The baseplate 1 10 supports a ceramic layer 1 12. In some examples, the ceramic layer 112 may comprise a heating layer, such as a ceramic multi-zoneheating plate. A thermal resistance layer 1 14 (e.g., a bond layer) may be arranged between the ceramic layer 1 12 and the baseplate 1 10. The baseplate 1 10 may include one or more coolant channels 1 16 for flowing coolant through the baseplate 1 10.

[0062] An RF generating system 120 generates and outputs an RF voltage to one of the upper electrode 104 and the lower electrode (e.g., the baseplate 1 10 of the substrate support 106). The other one of the upper electrode 104 and the baseplate 1 10 may be DC grounded, AC grounded or floating. For example only, the RF generating system 120 may include an RF voltage generator 122 that generates the RF voltage that is fed by a matching and distribution network 124 to the upper electrode 104 or the baseplate 110. In other examples, the plasma may be generated inductively or remotely. Although, as shown for example purposes, the RF generating system 120 corresponds to a capacitively coupled plasma (CCP) system, the principles of the present disclosure may also be implemented in other suitable systems, such as, for example only transformer coupled plasma (TCP) systems, CCP cathode systems, remote microwave plasma generation and delivery systems, etc.

[0063] A gas delivery system 130 includes one or more gas sources 132-1 , 132-2,..., and 132-N (collectively gas sources 132), where N is an integer greater than zero. The gas sources supply one or more precursors and mixtures thereof. The gas sources may also supply purge gas. Vaporized precursor may also be used. The gas sources 132 are connected by valves 134-1 , 134-2, ..., and 134-N (collectively valves 134) and mass flow controllers 136-1 , 136-2, ..., and 136-N (collectively mass flow controllers 136) to a manifold 140. An output of the manifold 140 is fed to the processing chamber 102. For example only, the output of the manifold 140 is fed to the showerhead 109.

[0064] A temperature controller 142 may be connected to a plurality of heating elements (e.g., thermal control elements or TCEs) 144 arranged in the ceramic layer 1 12. For example, the heating elements 144 may include, but are not limited to, macro heating elements corresponding to respective zones in a multi-zone heating plate and / or an array of micro heating elements disposed across multiple zones of a multi-zone heating plate. The temperature controller 142 may be used to control the plurality of heating elements 144 to control a temperature of the substrate support 106 and the substrate 108. Current is provided to the TCEs 144 to control the temperature of the substrate support 106 via connection terminals (not shown in FIG. 1 ) according to the principles of the present disclosure as described below in more detail.

[0065] The temperature controller 142 may communicate with a coolant assembly 146 to control coolant flow through the coolant channels 1 16. For example, the coolant assembly 146 may include a coolant pump and reservoir. The temperature controller 142 operates the coolant assembly 146 to selectively flow the coolant through the coolant channels 1 16 to cool the substrate support 106.

[0066] A valve 150 and pump 152 may be used to evacuate reactants from the processing chamber 102. A system controller 160 may be used to control components of the substrate processing system 100. A robot 170 may be used to deliver substrates onto, and remove substrates from, the substrate support 106. For example, the robot 170 may transfer substrates between the substrate support 106 and a load lock 172. Although shown as separate controllers, the temperature controller 142 may be implemented within the system controller 160. In some examples, a protective seal 176 may be provided around a perimeter of the bond layer 114 between the ceramic layer 1 12 and the baseplate 1 10.

[0067] The substrate support 106 includes an edge ring 180. The edge ring 180 may correspond to a top ring, which may be supported by a bottom ring 184. In some examples, the edge ring 180 may be further supported by one or more of a middle ring (not shown in FIG. 1 ), a stepped portion of the ceramic layer 112, etc. as described below in more detail. The edge ring 180 according to the principles of the present disclosure is moveable (e.g., moveable upward and downward in a vertical direction) relative to the substrate 108. For example, the edge ring 180 may be controlled via an actuator responsive to the system controller 160. In some examples, the edge ring 180 may be adjusted during substrate processing (i.e., the edge ring 180 may be a tunable edge ring). In other examples, the edge ring 180 may be removable (e.g., using the robot 170, via an airlock, while the processing chamber 102 is under vacuum). In still other examples, the edge ring 180 may be both tunable and removable.EXAMPLE OF SUBSTRATE SUPPORT (ESC)

[0068] FIG. 2 shows a simplified example of a substrate support 200. The substrate support 200 includes a baseplate 204 configured to support a ceramic layer 208. The ceramic layer 208 is configured to support a substrate 220 during processing. The baseplate 204 may include one or more coolant channels 228 for flowing coolant through the baseplate 204.

[0069] The ceramic layer 208 includes multiple zone heaters (also called macro heaters) 230 for bulk radial tuning and a grid of die-by-die heaters (also called micro heaters) 232 for non-radial tuning of temperature of the ceramic layer 208 during the processing of the substrate 220. The zone heaters 230 are independently controllable to coarsely control temperatures of respective zones of the ceramic layer 208. The die-by-die heaters 232 are distributed across multiple zones of the ceramic layer 208 and can be individually controlled to finely control temperatures in specific locations within the ceramic layer 208 to compensate for temperature non-uniformities, etc.

[0070] The die-by-die heaters 232 are independently controllable to provide localized, dynamic temperature tuning as explained below with reference to FIGS. 3 and 4. The heaters 230 and 232 are collectively called heater elements throughout the present disclosure. These heater elements provide the ability to fine-tune critical dimension (CD) non-uniformities based on metrology feedback. A circuit board (e.g., a distribution board) 240 is embedded in or adjacent to a bottom surface of the baseplate 204 to supply power (e.g., AC power, pulse width modulated DC power, etc.) to these heating elements.

[0071] FIG. 3 shows a simplified example of a substrate support 300, which is similar to the substrate support 200 shown in FIG. 2, in further detail. The substrate support 300 includes a baseplate 304 configured to support a ceramic layer 308. The ceramic layer 308 is configured to support a substrate (e.g., the substrate 220 shown in FIG. 2) during processing. The ceramic layer 308 includes a clamping electrode 314 to electrostatically clamp the substrate during processing when a voltage (e.g., V-Clamp) is applied to the clamping electrode 314. A thermal barrier layer 316 (e.g., a bond layer comprising a suitable bonding material) bonds the ceramic layer 308 to the baseplate 304. The baseplate 304 may include one or more coolant channels 328 for flowing coolant through the baseplate 304.

[0072] In the example shown, the ceramic layer 308 comprises a plurality of layers. In some implementations, all of the plurality of layers may comprise a ceramic material. In some implementations, the layer comprising the clamping electrode 314 may comprise a ceramic material, and the other layers may comprise other suitable electrically insulating material. Many other configurations and material compositions for the ceramic layer 308 are contemplated.

[0073] A plurality of heater elements 320 are arranged in the ceramic layer 308. Throughout the present disclosure, the terms heater elements, heating elements, andheaters are used interchangeably and synonymously using the same reference numeral 320. A diode 330 is connected in series with each heater element 320. A plurality of diodes 330 is embedded near the bottom of the ceramic layer 308 (i.e., closer to the thermal barrier layer 316). An expanded view of a dotted oval area 350 is shown in FIG. 5 to illustrate the diode 330 in further detail. A circuit board (e.g., a distribution board, similar to element 240 shown in FIG. 2) is embedded within or adjacent to a bottom surface of the baseplate 304 to supply power (e.g., AC power, pulse width modulated DC power, etc.) to the heating elements 320 via power supply and power return lines, denoted respectively as S and R throughout the figures.

[0074] Each heater element 320 is connected to one power supply line and one power return line connected to the circuit board. No two heater elements 320 share the same pair of power supply and power return lines. By providing suitable electrical switching arrangements in the circuit board, it is possible to connect a pair of power supply line and power return line to a power supply such that only one heater element 320 connected to this pair of power lines is powered. A time-averaged heating power of each heater element 320 can be individually tuned by employing time-domain multiplexing in the circuit board.ARRAY OF HEATERS AND DIODES

[0075] FIG. 4 shows a schematic representation of a heater matrix 400 comprising the heater elements 320 and the diodes 330. Connecting the diode 330 in series with the heater element 320 enables passive heater matrix addressing, which allows independent control of the heater elements 320 to provide fine local temperature control of the ceramic layer 308. The plurality of diodes 330 on the return side of the heater elements 320 between the heater element and the return line blocks the reverse flow of current through all the other heater elements ensuring that only the active heater element is powered. A controller 402 (e.g., the circuit board 240 shown in FIG. 2) controls multiplexers 404 and 406 to select one of the heater elements 320 so that power from a power supply 408 is supplied to the selected heater element 320.

[0076] Diodes embedded in ESC ceramic (e.g., the ceramic layer 308) allows realizing independent control of ESC heater array (e.g., the heater elements 320) because the diodes enable passive heater matrix addressing. Diodes are positioned on the return side of the heater elements between the heater element and the return line to block the reverse flow of current through all the other heater elements ensuring that only the activeheater element is powered. Inside ESC ceramic, diodes are embedded into ceramic cavities filled with potting material near bottom of ESC ceramic. A diode is typically in form of a bare silicon die, with cathode and anode on each side of die. Cathode of the die (bottom surface) is bonded to a metalized contact on the ceramic layer directly by soldering. Anode of the die (upper surface) is bonded to a metallic strap by solder. The metallic strap bridges between the die and an interconnect contact pad. Both cathode and anode are bonded to via contacts in the same layer as return line.

[0077] FIG. 5 shows the expanded view of the dotted oval area 350 shown in FIG. 3, which shows the diode 330 in further detail. The diode 330 (shown in FIG. 3) comprises a bare silicon die 500. The die 500 comprises a P and N type doped silicon. The die 500 is arranged in a cavity in the ceramic layer 308 (shown in FIG. 3) filled with a potting material 502 within the ceramic layer 308 (shown in FIG. 3). The potting material 502 generally comprises silicone. The cathode (K) and anode (A) of the diode 330 are bonded onto the ceramic layer 308 via contacts in the same layer as return lines.

[0078] The cathode K is bonded directly to a metalized contact on the ceramic layer 308 by solder material 504. The anode A is bonded by solder material 508 to a metallic (e.g., copper) strap 506 that bridges between the die 500 and an interconnect contact pad. Specifically, the anode A is bonded to a first end 506-1 of the metallic strap 506 by solder material 508. A second end 506-2 of the metallic strap 506 is bonded to an interconnect contact pad on the ceramic layer 308 by solder material 510. A via 512 connects the cathode K to a power return line R via the solder material 504. A via 514 connects the anode A to a first end of a heating element (e.g., the heating element 320 shown in FIG. 4) via the metallic strap 506 and the solder materials 510 and 508. A second end of the heating element is connected to a power supply line S (as shown in FIG. 4).

[0079] FIG. 6 shows a view 600 of FIG. 5 rotated by 180 degrees around a vertical axis. This orientation is presented to facilitate the discussions of the designs shown and described with reference to subsequent figures. Since FIG. 6 is identical to FIG. 5 in all respects, a description of FIG. 6 is unnecessary and is omitted for brevity.

[0080] Throughout the present disclosure, diodes 330 are used as examples of switches that can be selected to supply power to the heaters. Instead, a transistor or any other suitable semiconductor switching device can be used and can be selected to supply power to the heaters as described in the present disclosure. The heating elements 320 can comprise resistive heaters or any other suitable electronic component that cangenerate Joule (l2R) heat. The metallic straps described through the present disclosure can be called a connector, a metallic connector, or a conductor. Further, the solder described below can be called an electrically conducting material.THERMAL ISSUES WITH DIODES

[0081] The diode design shown in FIGS. 3-6 works reliably for a process recipe temperature range of 0 to 60-70C and for a chuck (or ceramic) temperature range Tmin,max = -20C, 120C. However, some emerging etch processes (e.g., boron doped carbon etch) require extended high chuck (ceramic) temperature up to -175C or more, as well as extreme and large process recipe temperature range (-140C). Diodes and metallic straps with the design shown in FIGS. 3-6 cannot survive at these extended operating temperature conditions, which exert excessive thermal stress and fatigue on the diodes and the metallic straps due to excessive chuck (ceramic) temperature and due to cycling temperature variations during different processes. Consequently, the diodes and / or the metallic straps tend to fail prematurely, which results in permanent and total ESC failure.

[0082] Specifically, using the metallic (e.g., copper) strap, reflow soldering, and silicone- based encapsulation polymer to form the embedded diode package (shown in FIGS. 3- 6) works well for a process recipe temperature range from 0 to 60-70C and a chuck (ceramic) temperature range Tmin,max = -20C, 120C. However, this design poses problems for ESC lifetime and substrate processing capability when expanding the process operating temperature range to more than 140C range and when expanding the chuck (ceramic) temperature range Tmin,max = -60C, 175+C. In these expanded temperature ranges, the above design can cause premature diode short failures and or metallic strap failures. Stated generally, the above diode design works well up to a certain threshold process recipe temperature range and up to a certain threshold chuck (ceramic) temperature range. The above diode design tends to fail beyond these thresholds.

[0083] The failure is caused by cracking of the silicon diode die near the electrical connection on the diode’s anode side. The cracking occurs largely due to materials having different coefficient of thermal expansion (CTE’s) at the diode’s bare die anode interface (e.g., CTE of silicon is 3.4 ppm / degC, and CTE of copper is 17.2 ppm / degC). The CTE mismatch between the silicon diode bare die and the metallic strap causesexcessive strain / stress on the diode’s top side electrode (i.e., anode) and on the metallic strap.

[0084] As FIG. 6 shows, at high temperatures (e.g., temperatures greater than the above thresholds), the anode and a straight portion 602 of the metallic strap 506 near the anode form a capillary through which the reflow solder reaches the edge of the diode as shown by the downward arrow. Further, silicon is a brittle material and cannot withstand excessive strain / stress under large cyclic temperature conditions required by the various emerging process recipes (e.g., Boron doped carbon etch).

[0085] Accordingly, the diodes and / or the metallic straps tend to fail prematurely. The failure of the diodes and / or the metallic straps causes process performance degradation and even permanent ESC failure. Premature failure requires replacement under warranty since the ESC cannot be repaired or refurnished after the failure of the diodes and / or the metallic straps. The diode failure causes ESC thermal runaway and potentially massive scrapping of production substrates due to lack of a robust failure detection mechanism. Consequently, a tool with the above diode design cannot be used for emerging etch applications (e.g., Boron doped carbon etch).THERMAL ISSUES WITH METALLIC STRAP

[0086] Some ESC designs combine multi-zone radial tunability with a grid (array) of many uniformly distributed heating elements (e.g., the heating elements 320 shown in FIG. 4). The grid provides tunability of non-radial components of the ESC. The grid comprises an array of small heaters (e.g., the heating elements 320 shown in FIG. 4) arranged above radial zone heaters closer to the substrate. The small heaters in the array are powered by a high DC voltage (e.g., +120V) bus and a ground bus. The heater circuit comprises diodes (comprising silicon carbide or SiC material) to address the matrix (array) of the small heaters. The diodes provide the ability to control the small heaters individually for fine-tuning the heating of the substrate. Metallic (e.g., copper) straps (e.g., the metallic strap 506) are used between the +120V bus and the anodes of the diodes for electrical contact. The electrical requirements of the metallic strap include conducting high current (e.g., 2A pulsed) at a voltage of +120VDC.

[0087] In the design shown in FIGS. 5 and 6, solder is used between the metallic strap and the diode. The metallic strap 506 has a single bend that exhibits stiffer behavior towards the diode end, followed by a straight portion. Both ends of the metallic strap are bent to contact the diode at one end and the ground bus at the other end. The assemblyof the metallic strap and solder is surrounded by bond material to enhance thermal conductivity. With the operating temperature range of the ESC being 0°C to 140°C, the temperature seen by the metallic strap at maximum ESC temperature is ~120°C. The ESC is also subjected to higher temperature ramp up and ramp down rates (called thermal cycling) for maximum wafer throughput and process recipe requirements.

[0088] In the design shown in FIGS. 5 and 6, the metallic strap, the diode, the solder material, and the surrounding bond have different coefficients of thermal expansion (CTEs). Due to the differences in CTE values, high CTE mismatch exists between the diode and the metallic strap. The high CTE mismatch causes excessive local strain / stress. The excessive local strain / stress leads to failures such as diode cracking, solder joint breakage / delamination, and metallic strap damage. The expected ESC lifecycle is typically ~1 Ok RF hours (RFH). However, due to the above-mentioned failures, the ESC experiences early life failures. Failure to control even one heater in the heater array due to the above-mentioned failures affects substrate processing and can also lead to failure of ESC itself as described above. The solder material at the diode interface experiences maximum strain. The stiffness of the existing metallic straps leads to high strain on the solder interface leading to solder cracking / delamination.

[0089] These issues are exacerbated by demanding process requirements where the ESC temperatures are increasing on the higher limit for emerging applications. As ESC high temperature limits increase, the temperature range (AT) between heating and cooling of the ESC will further increase, and the increase in AT will further reduce the ESC cycles to failure due to the above-mentioned problems.

[0090] To solve the above problems, the present disclosure provides several metallic strap designs with the geometry of the metallic straps optimized to minimize the strain at the solder interface. The metallic straps of the present disclosure are designed considering the impact on electrical conductivity, manufacturability, and strain / stress. The designs reduce the strain by 15-25% compared to the design shown in FIGS. 5 and 6. The reduction in strain increases cycles to failure for the ESC heaters. In the designs of the present disclosure, the straight portion between the bends (for making the solder contact shown in FIGS. 5 and 6) is replaced by a portion with variously shaped designs. For example, in one design, the straight portion is replaced by a sinusoidal wavy structure. In one of the designs, the width and thickness of the metallic strap is the same throughout the metallic strap, including the wave patterned structure. In another one ofthe designs, the wave patterned structure has a reduced width and thickness compared to the rest of the metallic strap. The bending angle of the metallic strap at the diode and the metallic strap interface is also reduced.

[0091] Additional designs are provided to reduce thermal stress and strain on the metallic straps in the heater array as described below in detail. The sinusoidal wavy structure and the other designs of the metallic straps have minimal impact on the functionality of the metallic straps. Further, as compared to the design shown in FIGS. 5 and 6, when the designs shown in FIGS. 7A-13B are subjected to thermal cycling, the amount of strain at the solder interface is reduced by 15-35%. The maximum stress experienced by the metallic straps shown in FIGS. 7A-13B is reduced by 30-35%. Accordingly, the metallic strap designs of the present disclosure shown in FIGS. 7A-13B directly increase the ESC lifecycle for failures.

[0092] The metallic strap designs of the present disclosure shown in FIGS. 7A-13B provide the following additional advantages: Minimal design change with no other changes in the ESC, leading to increased ESC lifecycles and substrate performance; cost neutral solution to increase ESC lifecycles; scalability to other ESCs that use the metallic strap design; additional buffer for high temperature requirements of ESCs for emerging applications; and no electrical or software changes to existing control systems.

[0093] Accordingly, the present disclosure provides various designs of metallic straps for connecting diodes and heaters embedded in electrostatic chucks that reduce local thermal stress around the die of the diodes and on the metallic straps. These designs increase the lifetime and the operating temperature range relative to the above diode design as explained below in detail. These designs result in not only extending the operating temperature window without compromising ESC reliability but also result in minimal cost and manufacturing process impact. These and other features of the metallic strap designs of the present disclosure are described below in detail with reference to FIGS. 7A-13B.

[0094] Throughout the following description, elements identified by reference numerals that are shown and described above with reference to FIGS. 3-6 are not described again for brevity. Further, while the metallic straps are described below as comprising a plurality of segments, in some examples, each of the metallic straps is a single, unitary, and integrated element. That is, the segments are not separate components and are notjoined to each other to form the metallic straps. Rather, a single piece of a metallic (e.g., copper) material is shaped (e.g., bent) as described below.

[0095] In other examples, two or more segments of a metallic strap can be joined together to form the metallic strap. For example, each segment of a metallic strap can be an individual element (a separate piece), and the individual, separate segments are joined together to form a metallic strap. Alternatively, two or more segments of a metallic strap may be unitary while the remaining segments of the metallic strap may be individual pieces, and the unitary and individual pieces are joined together to form the metallic strap.

[0096] FIGS. 7A and 7B show a first design of a metallic strap 700 for connecting the diodes 330 and the heaters 320 (both shown in FIG. 3) embedded in the substrate support 200 of FIG. 2 according to the present disclosure. In FIG. 7A, as described above with reference to FIG. 5, the diode 330 (shown in FIG. 3) comprises the die 500. The die 500 comprises the P and N type doped silicon forming the diode 330. The die 500 is arranged in a cavity in the ceramic layer 308 (shown in FIG. 3) filled with the potting material 502 within the ceramic layer 308 (shown in FIG. 3). The potting material 502 generally comprises silicone. The cathode (K) and anode (A) of the diode 330 are bonded onto the ceramic layer 308 via contacts in the same layer as return lines.

[0097] The cathode K is bonded directly to a metalized contact on the ceramic layer 308 by solder material 504. The anode A is bonded by solder material 508 to the metallic (e.g., copper) strap 700 that bridges between the die 500 and an interconnect contact pad. Specifically, the anode A is bonded to a first end 700-1 of the metallic strap 506 by solder material 508. A second end 506-2 of the metallic strap 506 is bonded to an interconnect contact pad on the ceramic layer 308 by solder material 510. A via 512 (shown in FIG. 5, shown schematically by a line in FIG. 7) connects the cathode K to a power return line R via the solder material 504. A via 514 (shown in FIG. 5, shown schematically by a line in FIG. 7) connects the anode A to a first end of a heating element (e.g., the heating element 320 shown in FIG. 4) via the metallic strap 700 and the solder materials 510 and 508. A second end of the heating element is connected to a power supply line S (as shown in FIG. 4).

[0098] The metallic strap 700 comprises a plurality of segments (described below) between the first end 700-1 and the second end 700-2. The segments are connected to the first end 700-1 and the second end 700-2 and to each other as described below. The first end 700-1 and the second end 700-2 are flat (i.e., straight and not bent) and lie in aplane parallel to a plane in which the die 500 lies in the cavity in the ceramic layer 308. The plane in which the first end 700-1 and the second end 700-2 lie is also parallel to the plane of the ceramic layer 308.

[0099] A first segment 702 of the metallic strap 700 extends from the first end 700-1 . The A first segment 702 extends away from the ceramic layer 308 at an acute angle alpha (a) relative to the plane. For example, the acute angle alpha (a) is between 25 and 45 degrees. The first segment 702 extends for a first distance (i.e., has a first length).

[0100] A second segment 704 of the metallic strap 700 extends from the first segment 702. The second segment 704 extends parallel to the plane. The second segment 704 extends for a second distance (i.e., has a second length). The second segment 704 extends up to a periphery of the solder material 508. The first and second segments 702, 704 contact the solder material 508.

[0101] A third segment 706 of the metallic strap 700 extends from the second segment 704. The third segment 706 extends away from the ceramic layer 308 at an acute angle alpha (a) relative to the plane. The third segment 706 extends for a third distance (i.e., has a third length). A fourth segment 708 of the metallic strap 700 extends from the third segment 706. The fourth segment 708 extends parallel to the plane. The fourth segment 708 extends for a fourth distance (i.e., has a fourth length). The third and fourth segments 706, 708 do not contact the solder material 508.

[0102] A fifth segment 710 of the metallic strap 700 comprises a plurality of sinusoidal turns. Accordingly, the fifth segment 710 can also be called a wavy segment. The number turns can vary. The fifth segment 710 extends parallel to the plane. The fifth segment 710 extends for a fifth distance (i.e., has a fifth length). The fifth segment 710 is greater in length than all other segments of the metallic strap 700. The fifth segment 710 does not contact the solder materials 508, 510.

[0103] A sixth segment 712 of the metallic strap 700 extends from the fifth segment 710. The sixth segment 712 extends at an acute angle relative to the plane towards the ceramic layer 308. The sixth segment 712 extends up to a periphery of the solder material 510. The sixth segment 712 extends for a sixth distance (i.e., has a sixth length). A seventh segment 714 of the metallic strap 700 extends from the sixth segment 712. The seventh segment 714 extends parallel to the plane. The seventh segment 714 extends for a seventh distance (i.e., has a seventh length).

[0104] An eighth segment 716 extends from the seventh segment 714. The eighth segment 716 extends at an acute angle relative to the plane towards the ceramic layer 308. The eighth segment 716 extends up to the second end 700-2. The eighth segment 716 extends for an eight distance (i.e., has an eighth length). The seventh and eighth segments 714, 716 contact the solder material 510.

[0105] FIG. 7B shows a top view of the metallic strap 700 shown in FIG. 7A. In the first design, all the segments of the metallic strap 700 have the same thickness Th and the same width W. Due to the acute angle alpha (a) between 25 and 45 degrees relative to the plane at which the first segment 702 extends from the first end 700-1 away from the ceramic layer 308, the local thermal stress around the die 500 and on the metallic strap 700 is reduced. The sinusoidal turns of the fifth segment 710 reduce the strain on the metallic strap 700. The sinusoidal turns of the fifth segment 710 reduce local thermal stress around the die 500 and on the metallic strap 700. The multiple bends in the metallic strap 700 reduce the stiffness of the metallic strap 700, which reduces the strain on the solder-diode interface and prevents solder cracking / delamination. Due to the reduction in stress and strain, the metallic strap 700 increases the lifetime and the operating temperature range of the ESC. The metallic strap 700 extends the operating temperature window without compromising ESC reliability and also results in minimal cost and manufacturing process impact.

[0106] FIG. 8 shows a second design of a metallic strap 800 for connecting the diodes 330 and the heaters 320 (both shown in FIG. 3) embedded in the substrate support 200 of FIG. 2 according to the present disclosure. The top view of the metallic strap 800 is identical to the top view of the metallic strap 700 shown in FIG. 7B. The metallic strap 800 is identical to the metallic strap 700 shown in FIGS. 7A and 7B except for the following difference. In the metallic strap 800, the acute angle alpha (a) relative to the plane at which the first segment 703 extends from the first end 700-1 away from the ceramic layer 308 is between 15 and 25 degrees. The smaller angle of the first segment 703 in the metallic strap 800 further reduces the strain on the solder-diode interface and prevents solder cracking / delamination and further reduces the local thermal stress around the die 500 and on the metallic strap 800. The multiple bends in the metallic strap 800 reduce the stiffness of the metallic strap 700, which reduces the strain on the solderdiode interface and prevents solder cracking / delamination.

[0107] FIG. 9A shows a third design of a metallic strap 900 for connecting the diodes 330 and the heaters 320 (both shown in FIG. 3) embedded in the substrate support 200 of FIG. 2 according to the present disclosure. FIG. 9B shows a top view of the metallic strap 900 shown in FIG. 9A. The metallic strap 900 is identical to the metallic strap 800 shown in FIG. 8 except for the following difference. The metallic strap 900 comprises a fifth segment 71 1 that differs from the fifth segment 710 of the metallic strap 700 as follows. In the metallic strap 900, the fifth segment 711 has a smaller thickness and width than the remainder (i.e., the remaining segments) of the metallic strap 900. For example, at least one of the thickness and width of the fifth segment 71 1 is less than or equal to half the thickness Th and less than or equal to half the width W of the remaining segments of the metallic strap 900. The smaller thickness and width of the fifth segment 71 1 in the metallic strap 900 further reduces the strain on the metallic strap 900.

[0108] FIG. 10 shows a fourth design of a metallic strap 1000 for connecting the diodes 330 and the heaters 320 (both shown in FIG. 3) embedded in the substrate support 200 of FIG. 2 according to the present disclosure. The top view of the metallic strap 1000 is identical to the top view of the metallic strap 700 shown in FIG. 7B. All the segments of the metallic strap 1000 described below have the same thickness Th and the same width W.

[0109] The metallic strap 1000 comprises the ends 700-1 , 700-2 and the segments 703, 704, 706, 708, 712, 714, and 716 that are identical to the same segments shown and described above with the same reference numerals in FIG. 8. These segments are therefore not described again for brevity. In addition, the metallic strap 1000 comprises multiple segments (fifth through eighth segments described below) between the segments 708 and 712. Accordingly, the segments 712, 714, and 716 of the metallic strap 1000 following the fifth through eighth segments are called ninth, tenth, and eleventh segments, respectively. The ninth, tenth, and eleventh segments 712, 714, and 716 of the metallic strap 1000 extend for ninth, tenth, and eleventh distances (i.e., have ninth, tenth, and eleventh lengths), respectively.

[0110] Following the fourth segment 708 of the metallic strap 1000, a fifth segment 1002 of the metallic strap 1000 extends from the fourth segment 708. The fifth segment 1002 extends at an acute angle relative to the plane towards the ceramic layer 308. The fifth segment 1002 extends for a fifth distance (i.e., has a fifth length). A sixth segment 1004 of the metallic strap 1000 extends from extends from the fifth segment 1002. The sixthsegment 1004 extends parallel to the plane. The sixth segment 1004 extends for a sixth distance (i.e., has a sixth length).

[0111] A seventh segment 1006 of the metallic strap 1000 extends from the sixth segment 1004. The seventh segment 1006 extends away from the ceramic layer 308 at an acute angle alpha (a) relative to the plane. The seventh segment 1006 extends for a seventh distance (i.e., has a seventh length).

[0112] An eighth segment 1008 of the metallic strap 1000 extends from the seventh segment 1006. The eighth segment 1008 extends parallel to the plane. The eighth segment 1008 extends for an eighth distance (i.e., has an eighth length). The eighth segment 1008 is greater in length than all other segments of the metallic strap 1000. The ninth segment 712 of the metallic strap 1000 extends from the eighth segment 1008, and so on as described above. The eighth segment 1008 does not contact the solder materials 508, 510.

[0113] The multiple bends provided by the first segment 703 through the seventh segment 1006 reduce the stiffness of the metallic strap 1000, which reduces the strain on the solder-diode interface, reduces local thermal stress around the die 500 and on the metallic strap 1000, and prevents solder cracking / delamination. Due to the reduction in stress and strain, the metallic strap 1000 increases the lifetime and the operating temperature range of the ESC. The metallic strap 1000 extends the operating temperature window without compromising ESC reliability and also results in minimal cost and manufacturing process impact

[0114] FIG. 1 1 shows a fifth design of a metallic strap for connecting the diodes 330 and the heaters 320 (both shown in FIG. 3) embedded in the substrate support 200 of FIG. 2 according to the present disclosure. The top view of the metallic strap 1100 is identical to the top view of the metallic strap 700 shown in FIG. 7B. All the segments of the metallic strap 1 100 have the same thickness Th and the same width W.

[0115] The metallic strap 1 100 is identical to the metallic strap 1000 except that the metallic strap 1 100 comprises the segment 702 instead of the segment 703, comprises additional segments between the segments 1006 and 1008, and the segment 1009 of the metallic strap 1 100 is shorter than the segment 1008 of the metallic strap 1000. In some examples, instead of the segment 702, the metallic strap 1 100 can comprise the segment 703, which bends at a more acute angle relative to the plane than the segment 702. The segment 1009 is the longest segment of the metallic strap 1 100.

[0116] The metallic strap 1100 comprises the segments 700-1 , 700-2, 702, 704, 706, 708, 1002, 1004, 1006, 712, 714, and 716 that are identical to the same segments shown and described above with the same reference numerals in FIG. 10. These segments are therefore not described again for brevity. In addition, the metallic strap 1 100 comprises multiple segments (seventh through twelfth segments described below) between the segments 1006 and 712. Accordingly, the segments 712, 714, and 716 of the metallic strap 1100 following the seventh through twelfth segments are called thirteenth, fourteenth, and fifteenth segments, respectively. The thirteenth, fourteenth, and fifteenth segments 712, 714, and 716 of the metallic strap 1 100 extend for thirteenth, fourteenth, and fifteenth distances (i.e., have thirteenth, fourteenth, and fifteenth lengths), respectively.

[0117] Following the seventh segment 1006 of the metallic strap 1100, an eighth segment 1 102 of the metallic strap 1 100 extends from the seventh segment 1006. The eighth segment 1102 extends parallel to the plane. The eighth segment 1 102 extends for an eighth distance (i.e., has an eighth length). A ninth segment 1 104 of the metallic strap 1 100 extends from the eighth segment 1 102. The ninth segment 1 104 extends towards the ceramic layer 308 at an acute angle relative to the plane. The ninth segment 1 104 extends for a ninth distance (i.e., has a ninth length).

[0118] A tenth segment 1106 of the metallic strap 1 100 extends from the ninth segment 1 104. The tenth segment 1 106 extends parallel to the plane. The tenth segment 1 106 extends for a tenth distance (i.e., has a tenth length). An eleventh segment 1 108 of the metallic strap 1 100 extends from the tenth segment 1106. The eleventh segment 1 108 extends away from the ceramic layer 308 at an acute angle relative to the plane. The eleventh segment 1108 extends for an eleventh distance (i.e., has an eleventh length).

[0119] A twelfth segment 1009 of the metallic strap 1 100 extends from the eleventh segment 1 108. The twelfth segment 1009 extends parallel to the plane. The twelfth segment 1009 extends for a twelfth distance (i.e., has a twelfth length). The twelfth segment 1009 is greater in length than all other segments of the metallic strap 1 100. The thirteenth segment 712 of the metallic strap 1 100 extends from the twelfth segment 1009, and so on as described above. The twelfth segment 1009 does not contact the solder materials 508, 510.

[0120] Accordingly, the segments of the metallic strap 1100 between the segments 702 and 1 109 form a zigzag pattern comprising straight and angled segments (straight andangular structures) that form shapes of the letters M and W. The structures can include a single piece or multiple pieces. The zigzag pattern comprises segments that extend parallel to the plane, segments that extend away from the ceramic layer 308 at an acute angle relative to the plane, and segments that extend towards the ceramic layer 308 at an acute angle relative to the plane. For example, the segments 706 through 1 104 comprise the straight and angled segments (straight and angular structures) that form a shape of the letter M. For example, the segments 1002 through 1 108 comprise the straight and angled segments (straight and angular structures) that form a shape of the letter W.

[0121] The multiple bends provided by the first segment 702 through the eleventh segment 1108 reduce the stiffness of the metallic strap 1 100, which reduces the strain on the solder-diode interface, reduces local thermal stress around the die 500 and on the metallic strap 1 100, and prevents solder cracking / delamination. Due to the reduction in stress and strain, the metallic strap 1 100 increases the lifetime and the operating temperature range of the ESC. The metallic strap 1 100 extends the operating temperature window without compromising ESC reliability and also results in minimal cost and manufacturing process impact.

[0122] FIG. 12 shows a sixth design of a metallic strap 1200 for connecting the diodes 330 and the heaters 320 (both shown in FIG. 3) embedded in the substrate support 200 of FIG. 2 according to the present disclosure. The top view of the metallic strap 1200 is identical to the top view of the metallic strap 700 shown in FIG. 7B. All the segments of the metallic strap 1 100 have the same thickness Th and the same width W.

[0123] The metallic strap 1200 is identical to the metallic strap 1 100 except that the metallic strap 1200 comprises a wavy segment 1202 instead of the straight segment 1009. Similar to the wavy segment 710 of the metallic strap 700, the wavy segment 1202 of the metallic strap 1200 comprises a plurality of sinusoidal turns. The number turns can vary. The wavy segment 1202 extends parallel to the plane. The wavy segment 1202 is the twelfth segment of the metallic strap 1200. The twelfth segment 1202 extends for a twelfth distance (i.e., has a twelfth length). The twelfth segment 1202 is greater in length than all other segments of the metallic strap 1200. The twelfth segment 1202 is the longest segment of the metallic strap 1200. The twelfth segment 1202 does not contact the solder materials 508, 510.

[0124] As in the metallic strap 1 100, in the metallic strap 1200, the segments between the segments 702 and 1 109 form a zigzag pattern comprising straight and angled segments (straight and angular structures) that form shapes of the letters M and W. The structures can include a single piece or multiple pieces. The zigzag pattern comprises segments that extend parallel to the plane, segments that extend away from the ceramic layer 308 at an acute angle relative to the plane, and segments that extend towards the ceramic layer 308 at an acute angle relative to the plane. For example, the segments 706 through 1 104 comprise the straight and angled segments (straight and angular structures) that form a shape of the letter M. For example, the segments 1002 through 1 108 comprise the straight and angled segments (straight and angular structures) that form a shape of the letter W. As in the metallic strap 1100, in some examples, instead of the segment 702, the metallic strap 1200 can comprise the segment 703, which bends at a more acute angle relative to the plane than the segment 702.

[0125] The multiple bends provided by the first segment 702 through the eleventh segment 1108 reduce the stiffness of the metallic strap 1200, which reduces the strain on the solder-diode interface, reduces local thermal stress around the die 500 and on the metallic strap 1200, and prevents solder cracking / delamination. Due to the reduction in stress and strain, the metallic strap 1200 increases the lifetime and the operating temperature range of the ESC. The metallic strap 1200 extends the operating temperature window without compromising ESC reliability and also results in minimal cost and manufacturing process impact.

[0126] FIG. 13A shows a seventh design of a metallic strap 1300 for connecting the diodes 330 and the heaters 320 (both shown in FIG. 3) embedded in the substrate support 200 of FIG. 2 according to the present disclosure. FIG. 13B shows a top view of the metallic strap 1300 shown in FIG. 13A. The metallic strap 1300 is identical to the metallic strap 1200 shown in FIG. 12 except for the following difference. The metallic strap 1300 comprises a twelfth segment 1302 that differs from the twelfth segment 1202 of the metallic strap 1200 as follows. In the metallic strap 1300, the twelfth segment 1302 has a smaller thickness and width than the remainder (i.e., the remaining segments) of the metallic strap 1300. For example, at least one of the thickness and width of the twelfth segment 1302 is less than or equal to half the thickness Th and less than or equal to half the width W of the remaining segments of the metallic strap 1300. The smaller thickness and width of the twelfth segment 1302 in the metallic strap 1300 further reduces the strain on the metallic strap 1300.

[0127] In some of the metallic straps described above, variations in thickness and width of segments are described. In some examples, only the thickness may be varied as described. In some examples, only the width may be varied as described. In other examples, both thickness and width may be varied as described. Further, within a metallic strap, only the thickness of one segment may be varied as described while only the width of another segment may be varied as described. Many combinations of variations in thickness and width of segments can be made within a metallic strap.

[0128] The foregoing description is merely illustrative in nature and is not intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent upon a study of the drawings, the specification, and the following claims.

[0129] It should be understood that one or more steps within a method may be executed in different order (or concurrently) without altering the principles of the present disclosure. Further, although each of the examples is described above as having certain features, any one or more of those features described with respect to any one of the examples of the disclosure can be implemented in and / or combined with features of any of the other examples, even if that combination is not explicitly described. In other words, the described examples are not mutually exclusive, and permutations of one or more examples with one another remain within the scope of this disclosure.

[0130] Spatial and functional relationships between elements (for example, between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including “connected,” “engaged,” “coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and “disposed.” Unless explicitly described as being “direct,” when a relationship between first and second elements is described in the above disclosure, that relationship can be a direct relationship where no other intervening elements are present between the first and second elements, but can also be an indirect relationship where one or more intervening elements are present (either spatially or functionally) between the first and second elements. As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A OR B OR C), using a non-exclusive logical OR, and should not be construed to mean “at least one of A, at least one of B, and at least one of C.”

[0131] In some implementations, a controller is part of a system, which may be part of the above-described examples. Such systems can comprise semiconductor processing equipment, including a processing tool or tools, chamber or chambers, a platform or platforms for processing, and / or specific processing components (a wafer pedestal, a gas flow system, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after processing of a semiconductor wafer or substrate.

[0132] The electronics may be referred to as the “controller,” which may control various components or subparts of the system or systems. The controller, depending on the processing requirements and / or the type of system, may be programmed to control any of the processes disclosed herein, including the delivery of processing gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, positional and operation settings, wafer transfers into and out of a tool and other transfer tools and / or load locks connected to or interfaced with a specific system.

[0133] Broadly speaking, the controller may be defined as electronics having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operation, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software).

[0134] Program instructions may be instructions communicated to the controller in the form of various individual settings (or program files), defining operational parameters for carrying out a particular process on or for a semiconductor wafer or to a system. The operational parameters may, in some examples, be part of a recipe defined by process engineers to accomplish one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0135] The controller, in some implementations, may be a part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the “cloud” or all or a part of a fab host computer system, which can allow for remote access of thewafer processing. The computer may enable remote access to the system to monitor current progress of fabrication operations, examine a history of past fabrication operations, examine trends or performance metrics from a plurality of fabrication operations, to change parameters of current processing, to set processing steps to follow a current processing, or to start a new process.

[0136] In some examples, a remote computer (e.g., a server) can provide process recipes to a system over a network, which may include a local network or the Internet. The remote computer may include a user interface that enables entry or programming of parameters and / or settings, which are then communicated to the system from the remote computer. In some examples, the controller receives instructions in the form of data, which specify parameters for each of the processing steps to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control.

[0137] Thus, as described above, the controller may be distributed, such as by comprising one or more discrete controllers that are networked together and working towards a common purpose, such as the processes and controls described herein. An example of a distributed controller for such purposes would be one or more integrated circuits on a chamber in communication with one or more integrated circuits located remotely (such as at the platform level or as part of a remote computer) that combine to control a process on the chamber.

[0138] Without limitation, example systems may include a plasma etch chamber or module, a deposition chamber or module, a spin-rinse chamber or module, a metal plating chamber or module, a clean chamber or module, a bevel edge etch chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etch (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, and any other semiconductor processing systems that may be associated or used in the fabrication and / or manufacturing of semiconductor wafers.

[0139] As noted above, depending on the process step or steps to be performed by the tool, the controller might communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboringtools, tools located throughout a factory, a main computer, another controller, or tools used in material transport that bring containers of wafers to and from tool locations and / or load ports in a semiconductor manufacturing factory.

Claims

CLAIMSWhat is claimed is:1 . A substrate support comprising: a semiconductor switching device arranged in an insulating layer of the substrate support, the semiconductor switching device configured to supply power to a heating element arranged in the insulating layer of the substrate support; and a metallic strap connecting the semiconductor switching device to the heating element, a first end of the metallic strap connected to the semiconductor switching device by an electrically conducting material, a second end of the metallic strap connected to the heating element by the electrically conducting material, the metallic strap comprising: a first segment extending from the first end of the metallic strap and extending away from the insulating layer of the substrate support at an acute angle relative to a plane of the insulating layer; a first plurality of segments comprising a series of angular structures with a first end of the first plurality of segments connected to the first segment; a second segment extending from a second end of the first plurality of segments; and a second plurality of segments extending from the second segment to the second end of the metallic strap connected to the heating element.

2. The substrate support of claim 1 wherein the series of angular structures have a shape of the letter “M” or the letter “W.”3. The substrate support of claim 1 wherein the acute angle is between 25 and 45 degrees.

4. The substrate support of claim 1 wherein the acute angle is between 15 and 25 degrees.

5. The substrate support of claim 1 wherein the second segment extends parallel to the plane of the insulating layer.

6. The substrate support of claim 1 wherein the second segment is straight.

7. The substrate support of claim 1 wherein the second segment is wave shaped.

8. The substrate support of claim 7 wherein the wave shape is sinusoidal.

9. The substrate support of claim 1 wherein the metallic strap has a uniform thickness and width.

10. The substrate support of claim 1 wherein the metallic strap is unitary.1 1 . The substrate support of claim 1 wherein at least one of a thickness and a width of the second segment is less than a thickness and less than a width of the rest of the metallic strap.

12. The substrate support of claim 1 wherein at least one of a thickness and a width of the second segment is less than half of a thickness and less than half of a width of the rest of the metallic strap.

13. The substrate support of claim 1 wherein at least one of the first plurality of segments and at least one of the second plurality of segments extend away from the plane of the insulating layer at an angle.

14. The substrate support of claim 1 wherein at least one of the first plurality of segments and at least one of the second plurality of segments extend towards the plane of the insulating layer at an angle.

15. A substrate support comprising: a semiconductor switching device arranged in an insulating layer of the substrate support, the semiconductor switching device configured to supply power to a heating element arranged in the insulating layer of the substrate support; and a metallic strap connecting the semiconductor switching device to the heating element, a first end of the metallic strap connected to the semiconductor switching device by an electrically conducting material, a second end of the metallic strap connected to the heating element by the electrically conducting material, the metallic strap comprising: a first segment extending from the first end of the metallic strap and extending away from the insulating layer of the substrate support at an acute angle relative to a plane of the insulating layer; a first plurality of segments with a first end connected to the first segment; a second segment extending from a second end of the first plurality of segments, the second segment being wave shaped, wherein at least one of a thickness and a width of the second segment is less than a thickness and less than a width of the rest of the metallic strap; and a second plurality of segments extending from the second segment to the second end of the metallic strap connected to the heating element.

16. The substrate support of claim 15 wherein at least one of a thickness and a width of the second segment is less than half of a thickness and less than half of a width of the rest of the metallic strap.

17. The substrate support of claim 15 wherein the wave shape is sinusoidal.

18. The substrate support of claim 15 wherein the acute angle is between 25 and 45 degrees.

19. The substrate support of claim 15 wherein the acute angle is between 15 and 25 degrees.

20. The substrate support of claim 15 wherein the second segment extends parallel to the plane of the insulating layer.

21. The substrate support of claim 15 wherein the rest of the metallic strap has a uniform thickness and width.

22. The substrate support of claim 15 wherein the metallic strap is unitary.

23. The substrate support of claim 15 wherein at least one of the first plurality of segments and at least one of the second plurality of segments extend away from the plane of the insulating layer at an angle.

24. The substrate support of claim 15 wherein at least one of the first plurality of segments and at least one of the second plurality of segments extend towards the plane of the insulating layer at an angle.

25. A substrate support comprising: a semiconductor switching device arranged in an insulating layer of the substrate support, the semiconductor switching device configured to supply power to a heating element arranged in the insulating layer of the substrate support; and a metallic strap connecting the semiconductor switching device to the heating element, a first end of the metallic strap connected to the semiconductor switching device by an electrically conducting material, a second end of the metallic strap connected to the heating element by the electrically conducting material, the metallic strap comprising: a first segment extending from the first end of the metallic strap and extending away from the insulating layer of the substrate support at an angle between 15 and 25 degrees relative to a plane of the insulating layer; a first plurality of segments with a first end connected to the first segment; a second segment extending from a second end of the first plurality of segments; and a second plurality of segments extending from the second segment to the second end of the metallic strap connected to the heating element.

26. The substrate support of claim 25 wherein the second segment extends parallel to the plane of the insulating layer.

27. The substrate support of claim 25 wherein the second segment is straight.

28. The substrate support of claim 25 wherein the second segment is wave shaped.

29. The substrate support of claim 25 wherein the wave shape is sinusoidal.

30. The substrate support of claim 25 wherein the metallic strap has a uniform thickness and width. 31 . The substrate support of claim 25 wherein the metallic strap is unitary.

32. The substrate support of claim 25 wherein at least one of the first plurality of segments and at least one of the second plurality of segments extend away from the plane of the insulating layer.

33. The substrate support of claim 25 wherein at least one of the first plurality of segments and at least one of the second plurality of segments extend towards the plane of the insulating layer.

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