Rapid and precise temperature control for thermal etching

Abstract

To provide a method and a device for rapidly and precisely controlling the temperature of a substrate during semiconductor processing.SOLUTION: An apparatus 100 includes: a processing chamber 102 including chamber walls 112A, and a chamber heater 116A that heats the chamber walls; and a pedestal 104 positioned within a chamber interior 114 and including a substrate heater 122 having a plurality of light emitting diodes (LEDs) that emit light having wavelengths in a range of 400 nanometers (nm) to 800 nm, a window 150 positioned above the substrate heater, comprising a material that is transparent to light having wavelengths in the range of 400 nm to 800 nm, and three or more substrate supports 108 that each have a substrate support surface 120 that is vertically offset from the window and that support a substrate such that the window and the substrate are offset by a non-zero distance.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] Incorporation by Reference The PCT application is filed concurrently herewith as a part of the present application. Each application to which this application claims benefit or priority, as identified in the concurrently filed PCT application, is incorporated herein by reference in its entirety for all purposes. [Background technology]

[0002] Semiconductor manufacturing often involves patterning schemes and other processes that selectively etch some materials while preventing etching of other exposed surfaces of the substrate. As device geometries become smaller and smaller, high etch selectivity processes are desirable to achieve effective etching of desired materials without plasma assistance.

[0003] The background discussion provided herein is intended to generally present the context for the present disclosure. The presently described work of the inventors, as well as aspects of the specification that do not otherwise qualify as prior art at the time of filing, are not admitted, expressly or impliedly, as prior art to the present disclosure, to the extent that they are described in this Background. Summary of the Invention [Problem to be solved by the invention]

[0004] The details of one or more implementations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, drawings, and claims. The following non-limiting implementations are considered part of this disclosure, and other implementations will become apparent from this disclosure and the accompanying drawings as a whole.

[0005] In some embodiments, an apparatus for semiconductor processing may be provided. The apparatus may include a processing chamber including a chamber wall at least partially in contact with the chamber interior and a chamber heater configured to heat the chamber wall; a substrate heater positioned within the chamber interior and having a plurality of light emitting diodes (LEDs) configured to emit light having a wavelength in a range of 400 nanometers (nm) to 800 nm; a window positioned above the substrate heater and having a top surface and a bottom surface opposite the top surface facing the LEDs, the window comprising a material that is transparent to light having a wavelength in the range of 400 nm to 800 nm; and three or more substrate supports, each substrate having a substrate support surface vertically offset from the window, the window and the three or more substrate supports configured to support substrates such that substrates supported by the three or more substrate supports are offset by a non-zero distance; a gas distribution unit including a protective plate having one or more fluid inlets and a plurality of through-holes fluidly connected to the one or more fluid inlets and the chamber interior, the protective plate having a front surface in partial contact with the chamber interior; and a unit heater thermally connected to the protective plate such that heat can be transferred between the protective plate and the unit heater.

[0006] In some embodiments, each substrate support may comprise a material that is transparent to light having wavelengths in the range of 400 nm to 800 nm.

[0007] In some embodiments, each of the three or more substrate supports may comprise quartz.

[0008] In some embodiments, the substrate support surface may be positioned closer to the central axis of the window than the outer diameter of the window top surface.

[0009] In some embodiments, each substrate support may include a temperature sensor configured to detect the temperature of a substrate positioned on the substrate support surface.

[0010] In some such embodiments, the temperature sensor may be a thermocouple.

[0011] In some embodiments, each substrate support surface may be vertically offset from the LED by a distance between 1 millimeter and 100 millimeters.

[0012] In some embodiments, the window may comprise quartz.

[0013] In some embodiments, the window may further include a sapphire coating.

[0014] In some embodiments, the window may not have a hole in the center.

[0015] In some embodiments, the top surface of the window may be non-planar.

[0016] In some embodiments, the bottom surface of the window may be non-planar.

[0017] In some embodiments, the bottom surface of the window may be in contact with at least the first set of LEDs.

[0018] In some embodiments, the base may further include a sidewall, and the exterior region of the window may be thermally connected to the sidewall such that heat may be transferred between the exterior region and the sidewall.

[0019] In some embodiments, the substrate heater may further include a printed circuit board, including a reflective material, on which the LEDs are supported.

[0020] In some embodiments, the pedestal may include a bowl in which the substrate heater is positioned, and the bowl may include one or more sidewalls having an exterior surface with a reflective material.

[0021] In some embodiments, the pedestal may further include a pedestal cooler that is thermally connected to the LED such that heat can be transferred between the LED and the pedestal cooler, the pedestal cooler including at least one flow path within the pedestal and configured to flow a cooling fluid within the at least one flow path.

[0022] In some embodiments, the pedestal may further include a pedestal heater configured to heat one or more exterior surfaces of the pedestal.

[0023] In some further such embodiments, the pedestal heater may be a resistive heater.

[0024] In some embodiments, the pedestal may include a fluid inlet configured to allow fluid to flow between the LED and the bottom surface of the window.

[0025] In some embodiments, the pedestal may be configured to move vertically.

[0026] In some embodiments, the pedestal may be configured to move vertically to create a vertical offset gap between the substrate support surface of the substrate support and the front surface of the protection plate of about 2 millimeters (mm) to about 70 mm.

[0027] In some embodiments, the first set of LEDs may be arranged in a first circle having a first radius about a central axis of the substrate heater and spaced apart at equal intervals, and the second set of LEDs may be arranged in a second circle having a second radius about the central axis that is greater than the first radius and spaced apart at equal intervals.

[0028] In some embodiments, a first set of LEDs may be electrically connected to form a first electrical zone, and a second set of LEDs may be electrically connected to form a second electrical zone, and the first and second electrical zones may be independently controllable.

[0029] In some embodiments, the plurality of LEDs may include more than about 1,000 LEDs, and the plurality of LEDs may be grouped to create at least about 80 independently controllable electrical zones.

[0030] In some such embodiments, the plurality of LEDs may include more than 5,000 LEDs.

[0031] In some embodiments, each LED may be configured to emit visible blue light.

[0032] In some embodiments, each LED may be configured to emit visible white light.

[0033] In some embodiments, each LED may use about 1.5 watts or less at full power.

[0034] In some embodiments, each LED may use about 4 watts or less at full power.

[0035] In some embodiments, each LED may be a chip-on-board LED.

[0036] In some embodiments, each LED may be a surface mount diode LED.

[0037] In some embodiments, the gas distribution unit may further include a second unit heater configured to heat the protective plate.

[0038] In some such embodiments, the second unit heater may be a resistive heater.

[0039] In some embodiments, the unit heater may include at least one flow path and may be configured to flow a heat transfer fluid through the at least one flow path.

[0040] In some embodiments, the apparatus may further include a mixing plenum fluidly connected to and upstream from at least one of the one or more fluid inlets of the gas distribution unit.

[0041] In some embodiments, the device may further include one or more sensors configured to measure one or more metrics of the visible light emitted by the LED.

[0042] In some embodiments, one or more of the sensors may be a photodetector.

[0043] In some such embodiments, the one or more metrics may include the light emitted by the LED.

[0044] In some embodiments, the apparatus may further include a pyrometer having a detector and an emitter, and the gas distribution unit may include a port extending through the protective plate and including a sensor window, and the emitter or detector may be connected to the port and sensor window through a fiber optic cable, and the emitter or detector may be positioned within the base and below the window.

[0045] In some such embodiments, the pyrometer may be configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, or about 1 to about 4 microns.

[0046] In some such embodiments, the pyrometer may be configured to detect emissions having wavelengths of about 1 micron, about 1.1 microns, and about 1 to about 4 microns.

[0047] In some such embodiments, the sensor window may be located in a central region of the apron.

[0048] In some embodiments, the chamber walls may comprise aluminum.

[0049] In some embodiments, the chamber walls may further include a plastic coating.

[0050] In some embodiments, the chamber walls may comprise a metal with a yttria coating.

[0051] In some embodiments, the chamber walls may comprise a metal with a zirconia coating.

[0052] In some embodiments, the chamber walls may comprise a metal or metal alloy with an aluminum oxide coating.

[0053] In some embodiments, the apparatus may further include a vacuum pump configured to create a vacuum inside the chamber, and the processing chamber may be configured to operate at a pressure range from about 0.1 Torr to about 100 Torr.

[0054] In some embodiments, the apparatus may further include a controller having a processor and one or more non-transitory memory devices storing instructions for causing the LED to emit visible light having a wavelength between 400 nm and 800 nm.

[0055] In some such embodiments, the apparatus may further include a cooling gas source fluidly connected to the one or more fluid inlets, and the one or more non-transitory memory devices further store instructions for flowing the cooling gas over the substrate.

[0056] In some further such embodiments, the pedestal may be configured to move vertically, and the one or more non-transitory memory devices may further store instructions for moving the pedestal vertically and offsetting the substrate from the protective plate by a non-zero gap of about 5 mm or less, and cooling gas may be flowed over the substrate while the substrate is offset from the protective plate by the non-zero gap.

[0057] In some embodiments, a method may be provided that may include supporting a substrate in a processing chamber having chamber walls using only a pedestal having multiple substrate supports each in contact with an edge region of the substrate, heating the substrate to a first temperature while the substrate is supported only by the multiple substrate supports by emitting visible light from multiple light emitting diodes (LEDs) below the substrate, the visible light having a wavelength between 400 nanometers (nm) and 800 nm, and etching a surface of the substrate while the substrate is supported only by the multiple substrate supports and while the substrate is at the first temperature.

[0058] In some embodiments, the method may further include cooling the substrate while the substrate is supported only by the plurality of substrate supports by one or more of flowing a cooling gas over the substrate and vertically moving the pedestal such that the substrate is offset from a protective plate of the gas distribution unit by a first non-zero offset distance, thereby transferring heat from the substrate to the protective plate through non-contact radiation.

[0059] In some such embodiments, cooling may be by both flowing a cooling gas and positioning the substrate at a first non-zero offset distance from the guard plate.

[0060] In some further such embodiments, the first non-zero offset distance may be 5 mm or less.

[0061] In some such embodiments, the cooling gas may include one or more of hydrogen and helium.

[0062] In some embodiments, the method may further include heating the chamber walls to a second temperature while the substrate is supported only by the plurality of substrate supports, and heating a protective plate of a gas distribution unit positioned above the substrate to a third temperature while the substrate is supported only by the plurality of substrate supports, wherein etching is performed while the chamber walls are heated to the second temperature and the protective plate is heated to the third temperature.

[0063] In some such embodiments, the second temperature and the third temperature may be between 30°C and 150°C.

[0064] In some embodiments, the supporting, heating, and etching may occur while the processing chamber is at a pressure between about 0.1 Torr and about 100 Torr.

[0065] In some embodiments, the supporting, heating, and etching may occur while the processing chamber is at a pressure between about 20 Torr and about 200 Torr.

[0066] In some embodiments, the first temperature may be from about 30°C to about 200°C.

[0067] In some embodiments, the first temperature may be between about 100°C and about 500°C.

[0068] In some embodiments, the method may further include measuring the temperature of the substrate using one or more temperature sensors and adjusting the power of at least a first set of the plurality of LEDs during heating, maintaining, and / or etching based on the measurement.

[0069] In some such embodiments, the one or more temperature sensors may include one or more of: a temperature sensor in at least one of the substrate supports; and a pyrometer comprising an emitter configured to emit radiation onto the substrate and a detector configured to receive emissions from the substrate, the temperature of the substrate, wherein the detector is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, or about 1 to about 4 microns.

[0070] In some further such embodiments, the emitter may be configured to detect emissions having wavelengths of about 1 micron, about 1.1 microns, and about 1 to about 4 microns.

[0071] In some further such embodiments, the one or more temperature sensors may include both a temperature sensor in at least one of the substrate supports and a pyrometer.

[0072] In some embodiments, the method may further include adjusting the power of at least a first set of the plurality of LEDs, and after the adjustment is made while the substrate is supported only by the plurality of substrate supports, heating the substrate to a second temperature by emitting visible light from the LEDs, and etching a bottom surface of the substrate while the substrate is supported only by the plurality of substrate supports and while the substrate is at the second temperature.

[0073] In some such embodiments, the method may further include measuring the temperature of the substrate using one or more temperature sensors, and the adjustment is made based at least in part on the measurement.

[0074] In some further such embodiments, the one or more temperature sensors may include one or more of a temperature sensor in at least one of the substrate supports and a pyrometer comprising an emitter configured to emit radiation onto the substrate and a receiver configured to receive emissions from the substrate, the temperature of the substrate, and the detector configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, or about 1 to about 4 microns.

[0075] In some further embodiments, the emitter may be configured to detect emissions having wavelengths of about 1 micron, about 1.1 microns, and about 1 to about 4 microns.

[0076] In some further embodiments, the one or more temperature sensors may include both a temperature sensor in at least one of the substrate supports and a pyrometer.

[0077] In some embodiments, supporting may further include supporting the substrate exclusively using a plurality of substrate supports comprising a material that is transparent to visible light having wavelengths between 400 nm and 800 nm.

[0078] In some embodiments, a method may be provided that includes emitting visible light from a plurality of light emitting diodes (LEDs) in a process chamber, the visible light having a wavelength between 400 nanometers (nm) and 800 nm, measuring one or more metrics of the visible light emitted by the LEDs using one or more sensors configured to detect the visible light emitted from the plurality of LEDs, and adjusting power of a first set of the plurality of LEDs based at least in part on the measurements, the first set including fewer LEDs than the plurality of LEDs.

[0079] In some embodiments, the measuring may further include measuring visible light using a photodetector.

[0080] In some such embodiments, the photodetector may be external to the processing chamber and connected to a port in the processing chamber via a fiber optic cable.

[0081] In some embodiments, a pedestal for use in a semiconductor processing chamber may be provided, the pedestal may include a window having a top surface and a bottom surface opposite the top surface, the window comprising a material that transmits visible light having a wavelength in the range of 400 nm to 800 nm, and three or more substrate supports, each substrate support comprising a material that transmits visible light having a wavelength in the range of 400 nm to 800 nm and having a substrate support surface configured to support a substrate such that substrates supported by the three or more substrates are offset by a non-zero distance, and the three or more substrate supports each having a temperature sensor configured to detect a temperature of a substrate positioned on the substrate support surface.

[0082] In some embodiments, each of the three or more substrate supports may comprise quartz.

[0083] In some embodiments, the substrate support surface may be positioned closer to the central axis of the window than the outer diameter of the window top surface.

[0084] In some embodiments, each temperature sensor may be a thermocouple.

[0085] In some embodiments, each substrate support surface may be vertically offset from the window by a distance of about 5 to 30 millimeters.

[0086] In some embodiments, the pedestal may further include a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit visible light with a wavelength in the range of 400 nm to 800 nm.

[0087] In some embodiments, a pedestal for use in a semiconductor processing chamber may be provided, the pedestal may include a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit visible light having a wavelength in the range of 400 nanometers (nm) to 800 nm, and a window having a top surface and a bottom surface opposite the top surface, the window comprising a material that is transparent to visible light having a wavelength in the range of 400 nm to 800 nm, wherein one or more of the top surface and the bottom surface is non-planar.

[0088] In some embodiments, both the top and bottom surfaces may be non-planar.

[0089] In some embodiments, the bottom surface of the window may be in contact with at least the first set of LEDs.

[0090] In some embodiments, the base may further include a sidewall, and the exterior region of the window may be thermally connected to the sidewall such that heat may be transferred between the exterior region and the sidewall.

[0091] In some embodiments, the substrate heater may further include a printed circuit board, including a reflective material, on which the LEDs are supported.

[0092] In some embodiments, the pedestal may include a bowl in which the substrate heater is positioned, and the bowl may include one or more sidewalls having an exterior surface with a reflective material.

[0093] In some embodiments, the pedestal may further include a pedestal cooler that is thermally connected to the LED such that heat can be transferred between the LED and the pedestal cooler, the pedestal cooler including at least one flow path within the pedestal and configured to flow a cooling fluid within the at least one flow path.

[0094] In some such embodiments, the pedestal may further include a pedestal heater configured to heat one or more exterior surfaces of the pedestal.

[0095] In some further such embodiments, the pedestal heater may be a resistive heater.

[0096] In some embodiments, the pedestal may include a fluid inlet and may be configured to allow fluid to flow between the LED and the bottom surface of the window.

[0097] In some embodiments, the first set of LEDs may be arranged in a first circle having a first radius about a central axis of the substrate heater and spaced apart at equal intervals, and the second set of LEDs may be arranged in a second circle having a second radius about the central axis that is greater than the first radius and spaced apart at equal intervals.

[0098] In some embodiments, a first set of LEDs may be electrically connected to form a first electrical zone, and a second set of LEDs may be electrically connected to form a second electrical zone, and the first and second electrical zones may be independently controllable.

[0099] In some embodiments, the plurality of LEDs may include more than 1,000 LEDs, and the plurality of LEDs may be grouped to create at least about 80 independently controllable electrical zones.

[0100] In some such embodiments, the plurality of LEDs may include more than 5,000 LEDs.

[0101] In some embodiments, each LED may be configured to emit visible blue light.

[0102] In some embodiments, each LED may be configured to emit visible white light.

[0103] In some embodiments, each LED may use about 1.5 watts or less at full power.

[0104] In some embodiments, each LED may use about 4 watts or less at full power.

[0105] In some embodiments, each LED may be a chip-on-board LED.

[0106] In some embodiments, each LED may be a surface mount diode LED.

[0107] In some embodiments, an apparatus may be provided that includes a processing chamber including a chamber wall at least partially in contact with a chamber interior, a pedestal positioned within the chamber interior and configured to support a substrate, and a pyrometer having a detector and an emitter, wherein the processing chamber includes a port above the pedestal and extending through a surface of the processing chamber including a sensor window, the emitter or detector connected to the port and the sensor window through a fiber optic cable, the emitter or detector positioned within the pedestal, and the pyrometer configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, or about 1 to about 4 microns.

[0108] In some embodiments, the pyrometer may be configured to detect emissions having wavelengths of about 1 micron, about 1.1 microns, and about 1 to about 4 microns.

[0109] In some embodiments, the sensor window may be located in a central region of the processing chamber.

[0110] In some embodiments, the processing chamber may further include a gas distribution unit including a protective plate having one or more fluid inlets and a plurality of through holes fluidly connected to the one or more fluid inlets and the interior of the chamber, the gas distribution unit having a front surface at least partially in contact with the interior of the chamber, and the ports may extend through the front surface of the protective plate.

[0111] In some embodiments, the device may further include one or more sensors configured to measure one or more metrics of the visible light emitted by the LED.

[0112] In some such embodiments, one or more sensors may be a photodetector.

[0113] In some such embodiments, the one or more metrics may include the light emitted by the LED.

[0114] In some embodiments, a method may be provided that may include supporting a substrate in a processing chamber having chamber walls using only a pedestal having multiple substrate supports each in contact with an edge region of the substrate, heating the substrate to a first temperature while the substrate is supported only by the multiple substrate supports by emitting visible light from multiple light emitting diodes (LEDs) below the substrate, the visible light having a wavelength of 400 nanometers (nm) to 800 nm, and cooling the substrate while the substrate is supported only by the multiple substrate supports by one or more of flowing a cooling gas over the substrate and vertically moving the pedestal such that the substrate is offset from a protection plate of a gas distribution unit by a first non-zero offset distance of 5 mm or less, thereby transferring heat from the substrate to the protection plate via non-contact radiation.

[0115] In some embodiments, cooling may be by flowing a cooling gas over the substrate.

[0116] In some embodiments, the cooling may be by positioning the substrate at a first non-zero offset distance from the protection plate.

[0117] In some embodiments, cooling may be by both flowing a cooling gas and positioning the substrate at a first non-zero offset distance from the guard plate.

[0118] In some such embodiments, the cooling gas may include one or more of hydrogen and helium. [Brief explanation of the drawings]

[0119] [Figure 1] FIG. 1 shows a cross-sectional side view of an exemplary device according to a disclosed embodiment.

[0120] [Figure 2] FIG. 2 shows a top view of a substrate heater with multiple LEDs.

[0121] [Figure 3] FIG. 3 shows a top view of another substrate heater having multiple LEDs.

[0122] [Figure 4] FIG. 4 illustrates the base of FIG. 1 with additional features, according to various embodiments.

[0123] [Figure 5] FIG. 5 shows the substrate support of FIGS. 1 and 4 according to a disclosed embodiment.

[0124] [Figure 6] FIG. 6 shows a plan view of a first exemplary apron.

[0125] [Figure 7] FIG. 7 shows a plan view of a second exemplary apron.

[0126] [Figure 8] FIG. 8 shows graphs of four different active cooling experiments.

[0127] [Figure 9] FIG. 9 shows an exemplary temperature control sequence.

[0128] [Figure 10] FIG. 10 illustrates a first technique for heat treatment according to disclosed embodiments.

[0129] [Figure 11] FIG. 11 illustrates a second technique for heat treatment according to disclosed embodiments.

[0130] [Figure 12] FIG. 12 illustrates a third technique for heat treatment according to disclosed embodiments.

[0131] [Figure 13] FIG. 13 shows a graph of silicon absorption at various wavelengths and temperatures.

[0132] [Figure 14] FIG. 14 illustrates the base of FIG. 4 with additional features, according to various embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0133] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the presented embodiments. The disclosed embodiments may be practiced without some or all of these specific details. In other instances, well-known process operations have not been described in detail in order to not unnecessarily obscure the disclosed embodiments. While the disclosed embodiments will be described in connection with specific embodiments, it will be understood that they are not intended to limit the disclosed embodiments.

[0134] Introduction and Background Semiconductor manufacturing processes often involve patterning and etching a variety of materials, including conductors, semiconductors, and dielectrics. Some examples include conductors such as metals or carbon, semiconductors such as silicon or germanium, and dielectrics such as silicon oxide, aluminum dioxide, zirconium dioxide, hafnium dioxide, silicon nitride, and titanium nitride. Atomic layer etching (ALE) processes provide a class of etching techniques that repeatedly change etching conditions during the etching operation. ALE processes remove thin layers of material using sequential, self-limiting reactions. Generally, an ALE cycle is the minimum set of operations used to perform a single etching process, such as etching a monolayer film. A single ALE cycle results in etching at least a portion of a film layer on the substrate surface. Typically, an ALE cycle includes a modification operation to form a reaction layer and a removal operation to remove or etch only this reaction layer. The cycle may also include certain auxiliary operations, such as removing one of the reactants or byproducts. Generally, a cycle includes one instance of a unique series of operations.

[0135] As an example, a conventional ALE cycle may include the following operations: (i) delivery of a reactive gas to perform a modification operation, (ii) purging the reactive gas from the chamber, (iii) delivery of a removal gas and optional plasma to perform a removal operation, and (iv) purging the chamber. In some embodiments, etching may be performed non-conformally. The modification operation generally forms a thin reactive surface layer that is less thick than the unmodified material. In an exemplary modification operation, the substrate may be chlorinated by introducing chlorine into the chamber. While chlorine is used as an exemplary etchant species or etching gas, it will be understood that different etching gases may be introduced into the chamber. The etching gas may be selected depending on the type and chemistry of the substrate being etched. A plasma may be ignited for the etching process, causing chlorine to react with the substrate, and the chlorine may react with the substrate or adsorb onto the surface of the substrate. Species generated from the chlorine plasma may be generated directly by forming a plasma in the process chamber containing the substrate, or may be remotely generated in a process chamber not containing the substrate and delivered into the process chamber containing the substrate.

[0136] In some cases, purging may be performed after the modification operation. In the purging operation, active chlorine species not in contact with the surface may be removed from the process chamber. This can be done by purging and / or evacuating the process chamber to remove the active species without removing the adsorbed layer. Species generated by the chlorine plasma can be removed by simply stopping the plasma and allowing the remaining species to decay, in any combination with purging and / or evacuating the chamber. Purging can be done using any inert gas, such as N2, Ar, Ne, He, and combinations thereof.

[0137] In the removal operation, the substrate may be exposed to an energy source to etch the substrate by directional sputtering (which may include activating or sputtering a gas or chemically reactive species that induces the removal). In some embodiments, the removal operation may be performed by ion bombardment using argon or helium ions. A bias may optionally be turned on during removal to promote directional sputtering. In some embodiments, the ALE may be isotropic, and in some other embodiments, the ALE is not isotropic when ions are used in the removal process.

[0138] In various examples, the modification and removal operations may be repeated in cycles, such as from about 1 to about 30 cycles, or from about 1 to about 20 cycles. Any suitable number of ALE cycles may be included to etch a desired amount of film. In some embodiments, ALE is performed in cycles to etch from about 1 Å to about 50 Å of the surface of the layer on the substrate. In some embodiments, the ALE cycle etches from about 2 Å to about 50 Å of the surface of the layer on the substrate. In some embodiments, each ALE cycle may etch at least about 0.1 Å, 0.5 Å, or 1 Å.

[0139] In some cases, prior to etching, the substrate may include a blanket layer of material such as silicon or germanium. The substrate may include a patterned mask layer previously deposited and patterned on the substrate. For example, a mask layer may be deposited and patterned on a substrate including a blanket amorphous silicon layer. A layer on the substrate may also be patterned. The substrate may have "features," such as fins or holes, characterized by one or more of narrow and / or reentrant openings, constrictions within the feature, and high aspect ratios. One example of a feature is a hole or via in a semiconductor substrate or a layer on the substrate. Another example is a trench in the substrate or layer. In various cases, the feature may have an underlayer, such as a barrier layer or an adhesion layer. Non-limiting examples of underlayers include dielectric layers and conductive layers, such as silicon oxide, silicon nitride, silicon carbide, metal oxide, metal nitride, metal carbide, and metal layers.

[0140] The use of plasma during conventional etching presents numerous challenges and drawbacks. For example, while it is generally desirable to create identical plasma conditions for each ALE cycle for a single substrate, as well as for all substrates in a batch, some plasmas change due to the accumulation of material in the process chamber, making it difficult to repeatedly reproduce the same plasma conditions. In addition, many conventional ALE processes can damage exposed components of the substrate, such as silicon oxide, resulting in defects, high pattern height ratios, and high pattern loads. Such defects can cause missing patterns and render the device unusable. Furthermore, plasma-assisted ALE utilizes smaller, more aggressive radicals, i.e., deeply dissociated radicals, which remove more material than the desired material, thereby reducing the selectivity of this etch. As a result, conventional ALE techniques are often not suitable for selectively etching some materials, such as aluminum dioxide, zirconium dioxide, hafnium dioxide, silicon nitride, and titanium nitride. Therefore, it is desirable to identify new etching techniques and apparatus that do not use plasma and can rapidly and precisely control the temperature of the substrate during processing.

[0141] More generally, it is an apparatus designed or configured to provide variable reaction conditions during an etching process, whether that process is an ALE process or some other etching process employing varying conditions. In certain embodiments, the apparatus is designed or configured to provide rapidly changing temperatures during an etching process.

[0142] Heat treatment equipment Provided herein are methods and apparatus for rapidly and precisely controlling the temperature of a substrate during semiconductor processing, including etching using thermal energy, rather than, or in addition to, plasma energy, to drive modification and removal operations. In certain embodiments, etching that relies primarily on chemical reactions coupled with thermal energy, rather than plasma, to drive the chemical reactions in modification and removal operations may be considered "thermal etching." This etching is not limited to ALE and is applicable to any etching technique.

[0143] In certain embodiments, thermal etching processes that employ one or more thermal cycles have relatively fast heating and cooling and relatively precise temperature control. In some cases, these features may be exploited to provide better throughput and / or reduce non-uniformity and wafer defects.

[0144] However, many conventional etching systems lack the ability to adjust and control the temperature of a substrate at an adequate rate. For example, while some etching systems may be capable of heating a substrate to multiple temperatures, these systems may only heat slowly, or may be unable to reach a desired temperature range, or may be unable to maintain the substrate temperature for a desired time and within a desired temperature range. Similarly, typical etching systems often are unable to cool a substrate quickly enough to enable high throughput, or to cool the substrate to a desired temperature range. For some applications, it is desirable to keep the temperature ramp time as short as possible, such as less than about 120 seconds in some embodiments, but many conventional etching systems are unable to heat, cool, or both, a substrate in less than that time, and some systems may take many minutes to cool and / or heat a substrate, slowing throughput.

[0145] In various embodiments, the apparatus described herein is designed or configured to rapidly heat and cool a wafer and precisely control the wafer temperature. In some embodiments, the wafer is rapidly heated and its temperature precisely controlled in part using visible light emitted from light-emitting diodes (LEDs) positioned in a pedestal beneath the wafer. The visible light may have a wavelength ranging from 400 nanometers (nm) to 800 nm, inclusive. The pedestal may include various features to enable wafer temperature control, such as lenses to advantageously direct or collect the emitted light, reflective materials to advantageously direct or focus the emitted light, and transparent windows that may have temperature control elements to assist in temperature control of the LEDs, pedestal, and chamber.

[0146] The apparatus may also thermally isolate or "float" the wafer within the processing chamber so that only minimal thermal mass is heated, ideally the substrate itself, thereby allowing for faster heating and cooling. The wafer may be rapidly cooled using radiative heat transfer to a heat sink, such as a cooling gas and a top plate (or other gas distribution element) above the wafer, or both. In some cases, the apparatus also includes temperature control elements within the processing chamber walls, pedestal, and top plate (or other gas distribution element) to allow for further temperature control of the wafer and processing conditions within the chamber, such as preventing unwanted condensation of processing gases and vapors.

[0147] The apparatus may also be configured to implement various control loops (e.g., with a controller configured to execute instructions that cause the apparatus to implement these loops) to accurately control wafer and chamber temperatures. This may include the use of various sensors to determine wafer and chamber temperatures as part of open-loop and feedback control loops. These sensors may include wafer support temperature sensors that contact the wafer to measure its temperature, and non-contact sensors such as photodetectors for measuring the light output of LEDs and pyrometers configured to measure the temperature of different types of wafers. As described in more detail below, some pyrometers determine the temperature of an item by emitting an infrared or other optical signal from the item and measuring the signal reflected or emitted by the item. However, many silicon wafers cannot be measured by some pyrometers because silicon can be optically transparent at various temperatures and with various processes, e.g., doped silicon or lightly doped silicon. For example, lightly doped silicon wafers at temperatures below 200°C transmit infrared signals. The novel pyrometers provided herein are capable of measuring multiple types of silicon wafers at various temperatures.

[0148] 1 shows a cross-sectional side view of an exemplary apparatus according to disclosed embodiments. As described in detail below, the apparatus 100 is capable of rapidly and precisely controlling the temperature of a substrate, such as for performing thermal etching operations. The apparatus 100 includes a process chamber 102, a pedestal 104 having a substrate heater 106 and multiple substrate supports 108 configured to support a substrate 118, and a gas distribution unit 110.

[0149] The processing chamber 102 includes sidewalls 112A, a top 112B, and a bottom 112C that at least partially define a chamber interior 114, which may be considered a plenum volume. As described herein, in some embodiments, it may be desirable to actively control the temperatures of the processing chamber walls 112A, top 112B, and bottom 112C to prevent unwanted condensation on the processing chamber surfaces. In some newer semiconductor processing operations, vapors, such as water vapor and / or alcohol vapor, flow over and adsorb onto the substrate, but may also undesirably adsorb onto the chamber's internal surfaces. This can result in unwanted deposition and etching on the chamber's internal surfaces, damaging the chamber surfaces, and potentially causing particulates to flake off onto the substrate, thereby contributing to substrate defects. To reduce and prevent unwanted condensation on the chamber's internal surfaces, the temperatures of the chamber walls, top, and bottom may be maintained at temperatures that do not cause condensation of chemicals used in the processing operation.

[0150] This active temperature control of the chamber surfaces may be achieved by using heaters to heat the chamber walls 112A, top 112B, and bottom 112C. As shown in FIG. 1 , chamber heater 116A is positioned on and configured to heat the chamber walls 112A, chamber heater 116B is positioned on and configured to heat the top 112B, and chamber heater 116C is positioned on and configured to heat the bottom 112C. The chamber heaters 116A-116C may be resistive heaters configured to generate heat when an electric current flows through a resistive element. The chamber heaters 116A-116C may also be fluid conduits through which a heat transfer fluid, such as a heating fluid that may include heated water, may flow. In some cases, the chamber heaters 116A-116C may be a combination of both a heating fluid and a resistive heater. The chamber heaters 116A-116C are configured to generate heat to bring the interior surface of each of the chamber walls 112A, top 112B, and bottom 112C to a desired temperature, which may be in the range of about 40° C. to about 150° C., including, for example, about 80° C. to about 130° C., about 90° C., or about 120° C. It has been discovered that under certain conditions, water vapor and alcohol vapor do not condense on surfaces maintained at about 90° C. or above.

[0151] The chamber walls 112A, top 112B, and bottom 112C may also be constructed from a variety of materials capable of withstanding the chemicals used in processing techniques. These chamber materials may include, for example, aluminum, anodized aluminum, aluminum with a polymer such as plastic, a metal or metal alloy with a yttria coating, a metal or metal alloy with a zirconia coating, and a metal or metal alloy with an aluminum oxide coating, and in some cases, the coating materials may be blended or layered with different combinations of materials, such as alternating layers of aluminum oxide and yttria or aluminum oxide and zirconia. These materials are configured to withstand the chemicals used in processing techniques, such as anhydrous HF, water vapor, methanol, isopropyl alcohol, chlorine, fluorine gas, nitrogen gas, hydrogen gas, helium gas, and mixtures thereof.

[0152] The apparatus 100 may also be configured to perform processing operations at or near a vacuum, such as at a pressure of about 0.1 Torr to about 100 Torr, or about 20 Torr to about 200 Torr, or about 0.1 Torr to about 10 Torr. The apparatus may also include a vacuum pump 184 configured to evacuate the chamber interior 114 to a low pressure, such as a vacuum having a pressure of about 0.1 Torr to about 100 Torr, including about 0.1 Torr to about 10 Torr, and about 20 Torr to about 200 Torr, or about 0.1 Torr to about 10 Torr.

[0153] Various features of the pedestal 104 are now discussed. The pedestal 104 includes a heater 122 (enclosed in FIG. 1 by a dashed rectangle) having a plurality of LEDs 124 configured to emit visible light having wavelengths between 400 nm and 800 nm, including 450 nm. The heater LEDs emit this visible light onto the backside of the substrate to heat the substrate. Visible light having a wavelength between approximately 400 nm and 800 nm can rapidly and efficiently heat a silicon wafer to ambient temperatures, e.g., between approximately 20°C and approximately 600°C, because silicon absorbs light in this range. In contrast, radiative heating, including infrared radiation, may not effectively heat silicon up to temperatures below approximately 400°C because silicon tends to be transparent to infrared radiation below that temperature. Additionally, radiative heating that directly heats the top surface of the wafer, as in many conventional semiconductor processes, can cause damage or other adverse effects to the top surface film. Many "hot plate" heaters that rely on solid-state heat transfer between a substrate and a hot plate, such as a pedestal with a heating coil, have relatively slow heating and cooling rates and non-uniform heating that can result from substrate warping and inconsistent contact with the hot plate. For example, some pedestals may take many minutes to heat to a desired temperature, heat to a first or second higher temperature, and then cool to a similar lower temperature.

[0154] Figure 13 shows a graph of silicon absorption at various wavelengths and temperatures. The x-axis represents light wavelength, the vertical axis represents absorbance, with 1.0 representing the maximum (i.e., 100%), and the data represent the optical absorbance of silicon at different temperatures. As can be seen in region 1, silicon absorption for light between 400 nm and 800 nm remains relatively constant as the temperature of the silicon changes. However, silicon's absorbance for infrared light, i.e., light with wavelengths greater than about 1 micron, changes with the temperature of the silicon. As a result, silicon absorption does not remain constant until the temperature reaches 600°C. In addition, the absorption range for various wavelengths and temperatures is small compared to the visible range. For example, silicon at 270°C has very low absorbance of about 0.05 or 5% for infrared radiation from about 1.8 microns to about 6 microns, followed by inconsistent absorbance from about 6 microns to 10 microns. Silicon at 350°C has the next lowest absorbance for infrared light, ranging from about 10% to 20% from about 1.8 microns to about 5 microns. Therefore, the use of visible light provides a constant absorption rate independent of the temperature of the silicon.

[0155] The heater's multiple LEDs may be arranged, electrically connected, and electrically controlled in various ways. Each LED may be configured to emit visible blue light and / or visible white light. In certain embodiments, white light (generated using a wavelength range in the visible portion of the electromagnetic spectrum) is used. In some semiconductor processing operations, white light can reduce or prevent unwanted thin-film interference. For example, some substrates have backside films that reflect different light wavelengths in varying amounts, resulting in uneven and potentially inefficient heating. Using white light can reduce this unwanted reflection variation by averaging out the thin-film interference across the broad visible spectrum provided by white light. In some cases, it may be advantageous to use visible non-white light, such as blue light having a wavelength of 450 nm, to provide a single or narrow-band wavelength that may provide more efficient, intense, and directed heating for some substrates that are more susceptible to absorbing narrow-band wavelengths than white light, depending on the substrate's backside material.

[0156] Various types of LEDs may be employed. Examples include chip-on-board (COB) LEDs or surface-mount diode (SMD) LEDs. In the case of SMD LEDs, the LED chip may be fused to a printed circuit board (PCB), which may have multiple electrical contacts that allow control of each diode on the chip. For example, a single SMD chip may have three diodes (e.g., red, blue, or green) that can be individually controllable to create different colors. SMD LED chips may range in size from 2.8x2.5mm, 3.0x3.0mm, 3.5x2.8mm, 5.0x5.0mm, and 5.6x3.0mm. In the case of COB LEDs, each chip may have three or more diodes printed on the same PCB, such as nine, twelve, dozens, or even hundreds or more. COB LED chips typically have two contacts per circuit, regardless of the number of diodes, thereby providing a simple design and efficient monochromatic application. The ability and performance of the LEDs to heat the substrate may be measured by the wattage of heat each LED emits, which may directly contribute to heating the substrate.

[0157] FIG. 2 shows a top view of a substrate heater 122 having multiple LEDs. The substrate heater 122 includes a printed circuit board 126 and a plurality of LEDs 124, some of which are labeled. The illustrated plurality of LEDs is approximately 1,300. External connections 128 are connected by wires to provide power to the plurality of LEDs 124. As shown in FIG. 2, the LEDs may be arranged along multiple arcs radially offset by different radii from a center 130 of the substrate heater 122, and within each arc, the LEDs may be equally spaced apart from one another. For example, one arc 132 is surrounded by a partially molded point shape, includes 16 LEDs 124, and is part of a circle of radius R extending around the center 130. The 16 LEDs 124 may be considered to be equally spaced apart from one another along this arc 132.

[0158] In some embodiments, the LEDs may also be arranged along a circle around the center of the substrate heater. In some cases, some LEDs may be arranged along a circle and other LEDs may be arranged along an arc. FIG. 3 shows a top view of another example of a substrate heater having multiple LEDs. This substrate heater 322 includes a printed circuit board 326 and multiple LEDs 324, some of which are labeled. Here, the LEDs 324 are arranged along multiple circles radially offset by different radii from the center 330 of the substrate heater 322, and in each circle, the LEDs may be equally spaced from one another. For example, one circle 334 is surrounded by a partially molded ring, includes 78 LEDs 324, and has a radius R extending around the center 330. The 78 LEDs 324 may be considered to be equally spaced from one another along this circle 334. The LED arrangement of Figure 3 may provide a more uniform light and heat distribution pattern across the backside of the substrate, particularly because the substrate and heater remain stationary relative to each other during processing and the substrate and substrate heater do not rotate, as the area of ​​the substrate heater 122 of Figure 2 that includes external connections may provide unheated cold spots on the wafer.

[0159] In some embodiments, the plurality of LEDs may include at least about 1,000 LEDs, including, for example, about 1,200, 1,500, 2,000, 3,000, 4,000, 5,000, or 6,000 or more. Each LED may be configured to use at least 4 watts at 100% power or less, including, in some cases, 3 watts at 100% power and 1 watt at 100% power. The LEDs are arranged in individually controllable zones and electrically connected to allow for temperature control and fine-tuning across the substrate. In some cases, the LEDs may be grouped into, for example, at least 20 independently controllable zones, including, for example, at least about 25, 50, 75, 80, 85, 90, 95, or 100 zones. These zones may allow for radial and azimuthal (i.e., angular) temperature control. These zones can be arranged in a defined pattern, such as a rectangular grid, a hexagonal grid, or other suitable pattern to generate a desired temperature profile. The zones can also have various shapes, such as square, trapezoidal, rectangular, triangular, elliptical, oval, circular, annular (e.g., ring), partial annular (i.e., annular sector), arc, arc, and sector centered on the center of the heater and having a radius equal to or less than the overall radius of the PCB of the substrate heater. For example, in FIG. 2 , the LEDs have 88 zones organized into at least 20 concentric rings, such as 20 or 21. These zones can adjust the temperature at multiple locations on the wafer to create a more uniform temperature distribution and a desired temperature profile, such as a higher temperature around the edge of the substrate than the center of the substrate. Independent control of these zones can also include the ability to control the power output of each zone. For example, each zone may have at least 15, 20, or 25 adjustable power outputs. In some cases, each zone may have one LED, allowing each LED to be individually controlled and adjusted, resulting in a more uniform heating profile on the substrate. Thus, in some embodiments, each LED of multiple LEDs in a substrate heater may be individually controllable.

[0160] In certain embodiments, the substrate heater 122 is configured to heat the substrate to multiple temperatures and maintain each such temperature for various durations. These durations may include, but are not limited to, at least about 1 second, at least about 5 seconds, at least about 10 seconds, at least about 30 seconds, at least about 60 seconds, at least about 90 seconds, at least about 120 seconds, at least about 150 seconds, or at least about 180 seconds. The substrate heater may be configured to heat the substrate to, for example, about 50°C to 600°C, including, for example, about 50°C to 150°C, about 130°C, or about 150°C to 350°C. The substrate heater may be configured to maintain the substrate at a temperature within these ranges for various durations, including, but not limited to, at least about 1 second, at least about 5 seconds, at least about 10 seconds, at least about 30 seconds, at least about 60 seconds, at least about 90 seconds, at least about 120 seconds, at least about 150 seconds, or at least about 180 seconds. Additionally, in some embodiments, the substrate heater 122 is configured to heat the substrate to any temperature within these ranges, for example, in less than about 60 seconds, less than about 45 seconds, less than about 30 seconds, or less than about 15 seconds. In particular embodiments, the substrate heater 122 is configured to heat the substrate at one or more heating rates, such as, for example, at least about 0.1° C. / sec to at least about 20° C. / sec.

[0161] The substrate heater may increase the temperature of the substrate by causing the LEDs to emit visible light at one or more power levels, including at least about 80%, at least about 90%, at least about 95%, or at least about 100%. In some embodiments, the substrate heater is configured to emit light at about 10 W to 4000 W, including at least about 10 W, at least about 30 W, at least about 0.3 kilowatts (kW), at least about 0.5 kW, at least about 2 kW, at least about 3 kW, or at least about 4 kW. The apparatus is configured to provide about 0.1 kW to 9 kW of power to the pedestal, and a power supply (not shown) is connected to the substrate heater through the pedestal. During the temperature ramp, the substrate heater may operate at a high power output or at a lower power level (e.g., between about 5 W and about 0.5 kW) to maintain the temperature of the heated substrate.

[0162] The pedestal may include a reflective material on its inner surface that, during operation, reflects light emitted by the LEDs toward the backside of the substrate supported by the pedestal. In some such embodiments, the substrate heater may include such a reflective material positioned on the top surface 140 of the PCB 126 on which the plurality of LEDs 124 are positioned, as shown in FIG. 1 . The reflective material may be composed of aluminum, such as polished aluminum, stainless steel, aluminum alloys, nickel alloys, and other protective layers that can prevent oxidation of the metal and / or increase reflectivity at specific wavelengths, such as reaching reflectivity of greater than 99% for those wavelengths, as well as other durable reflective coatings. Additionally or alternatively, the pedestal 104 may include a bowl 146 in which the substrate heater 122 is at least partially positioned. The bowl 146 may have an exposed inner surface 148 of a pedestal sidewall 149 on which the reflective material may be positioned. This reflective material increases the heating efficiency of the substrate heater and reduces unwanted heating of the PCB 126 and pedestal 104 by advantageously directing light that would otherwise be absorbed by the PCB 126 and pedestal 104 back onto the substrate.

[0163] In some embodiments, the substrate heater may also include a pedestal cooler thermally connected to the LEDs so that heat generated by the LEDs can be transferred from the LEDs to the pedestal cooler. This thermal connection is such that heat can be conducted from the LEDs to the pedestal cooler along one or more heat flow paths between these components. In some cases, the pedestal cooler is in direct contact with one or more elements of the substrate heater, while in other cases, another conductive element, such as a thermally conductive plate (e.g., comprising metal), is interposed between the substrate heater and the pedestal cooler. Referring back to FIG. 1 , the substrate heater includes a pedestal cooler 136 in direct contact with the bottom surface of the PCB 126. Heat is configured to flow from the LEDs to the PCB 126 and then to the pedestal cooler 136. The pedestal cooler 136 also includes a plurality of fluid conduits 138 configured to allow a heat transfer fluid, such as water, to flow through them to receive heat and thus cool the LEDs within the substrate heater 122. The fluid conduit 138 may be located external to the chamber and connected to a reservoir and pump (not shown). In some cases, the pedestal cooler may be configured to flow water cooled to about 5°C to 20°C, for example.

[0164] As provided herein, it may be advantageous to actively heat the exterior surface of the processing chamber 102. In some cases, it may also be advantageous to heat the exterior surface of the pedestal 104 to prevent unwanted condensation and deposition on the exterior surface of the pedestal 104. As shown in FIG. 1 , the pedestal 104 may further include a pedestal heater 144 configured to heat the exterior surface of the pedestal 104, including the side surface 142A and the bottom surface 142B. The pedestal heater 144 may include one or more heating elements, such as one or more resistive heating elements, and a fluid conduit configured to carry a heated fluid. In some cases, both the pedestal cooler and the pedestal heater may have fluid conduits fluidly connected to each other, such that the same heat transfer fluid may flow to both the pedestal cooler and the pedestal heater. In these embodiments, the fluid may be heated to between 50°C and 130°C, including between approximately 90°C and 120°C.

[0165] The pedestal may also include a window to protect the substrate heater, including the plurality of LEDs, from damage due to exposure to the process chemicals and pressures used during processing operations. As shown in FIG. 1 , a window 150 may be positioned above the substrate heater 122 and sealed to the sidewall 149 of the pedestal 104 to create a plenum volume within the pedestal that is fluidly isolated from the chamber interior. This plenum volume may also be considered the interior of the bowl 146. The window may be constructed of one or more materials that are optically transparent to visible light emitted by the LEDs, including light having wavelengths in the range of 400 nm to 800 nm. In some embodiments, this material may be quartz, sapphire, quartz with a sapphire coating, or calcium fluoride (CaF). The window may also be free of any holes or openings therein. In some embodiments, the heater may have a thickness of 15 to 30 mm, including 20 to 25 mm.

[0166] FIG. 4 illustrates the pedestal of FIG. 1 with additional features, according to various embodiments. As identified in FIG. 4 , the window 150 includes a top surface 152 that faces the substrate 118 supported by the pedestal 104 and a bottom surface 154 that faces the substrate heater 122. In some embodiments, the top surface 152 and the bottom surface 154 may be flat, planar (or substantially flat, e.g., within ±10% or 5% of flat). In some other cases, the top surface 152, the bottom surface 154, or both the top surface 152 and the bottom surface 154 may be non-planar. The non-planarity of these surfaces may be configured to refract and / or direct light emitted by the LEDs 124 of the substrate heater 122 to more efficiently and / or effectively heat the wafer. Additionally, the non-planarity may be along some or all of the surface. For example, the entire base surface may have a convex or concave curvature, or in another example, an outer annular region of the base surface may have a convex or concave curvature, with the remainder of the surface being flat. In a further example, the surfaces may have multiple, but different, non-flat portions, such as a conical portion at the center of the surface adjacent to a planar annular portion, adjacent to a conical prefix surface at the same or different angle as the conical portion. In some embodiments, window 150 may have features that act as an array of lenses oriented to collect light emitted by one or more LEDs, such as each LED.

[0167] With the window 150 positioned above the substrate heater 122, the window 150 can be heated by the substrate heater 122 and affect the thermal environment around the substrate. Depending on the material or materials used for the window 150, such as quartz, the window may retain heat and become increasingly heat-retaining over the course of processing one or more substrates. This heat can be radiatively transferred to the substrate, thus directly heating it. In some cases, the window can cause a temperature rise of 50°C to 80°C above the heater temperature. This heat may also create a temperature gradient through the thickness of the window or in the vertical direction of the window. In some cases, the top surface 152 is 30°C hotter than the bottom surface 154. Therefore, it may be advantageous to adjust and configure the chamber to account for and reduce the thermal effects of the window. As described in more detail below, this may include sensing the temperature of the substrate and adjusting the substrate heater to account for the heat retained by the window.

[0168] This may also include various configurations of the pedestal, such as actively cooling the window. In some embodiments, such as those shown in FIGS. 1 and 4, the window 150 may be offset from the substrate heater 122 by a first distance 156. In some embodiments, this first distance may be between about 2 mm and 50 mm, including between about 5 mm and 40 mm. A cooling fluid, such as an inert gas, may be flowed between the window 150 and the substrate heater 122 to cool both the window 150 and the substrate heater 122. The pedestal may have one or more inlets and one or more outlets for flowing this gas into the plenum volume, or bowl 146, of the pedestal 104. The one or more inlets are fluidly connected to a source of inert gas external to the chamber 102, which may include through a fluid conduit that may run at least partially through the interior of the pedestal 104. The one or more outlets are fluidly connected to an exhaust or other environment external to the chamber 102, which may also be through a fluid conduit that runs through the interior of the pedestal. In Figure 14, which shows the pedestal of Figure 4 with additional features, according to various embodiments, one or more inlets 151 are positioned in the sidewall 149 and extend through the surface 148, and the one or more inlets are also fluidly connected to an inert gas source 1472 partially through a fluid conduit 155 through the pedestal 104. A single outlet 153 is positioned in a central region of the substrate heater 122, i.e., not exactly in the center, but very close to it. In some embodiments, the one or more gas inlets and one or more outlets may be interchanged, such that one or more outlets extend through the sidewall 149 (i.e., they are item 151 in Figure 14) and one or more inlets may be in the central region of the substrate heater 122 (i.e., they are item 153 in Figure 14). In some embodiments, there may be one or more outlets, and in some embodiments, there may only be a single gas inlet. In some embodiments, one or more gas inlets extend through the inner surface 148 of the base sidewall 149 below the LED heater 122, and one or more gas outlets extend through another portion of the base sidewall 149, such as a mounting bracket between the LED heater 122 and the base sidewall 149.

[0169] In some embodiments, the window 150 may be disposed in direct thermal contact with a substrate heater, and a pedestal cooler may be configured to cool both the PCB and the window. In some embodiments, as also shown in FIGS. 1 and 4 , the window 150 may be thermally connected to the sidewall 149 of the pedestal 104 to transfer a portion of the heat retained in the window 150 to the pedestal 104. This transferred heat may be further transferred out of the pedestal using, for example, a pedestal heater 144, which may flow a heated fluid, e.g., between about 20° C. and 100° C., through the pedestal 104. This heated fluid may be cooler than the temperature of the pedestal 104 at the thermal connection with the window 150. In some embodiments, the window 150 may have one or more fluid conduits within the window 150, which may be configured to allow a transparent cooling fluid to flow through the window 150. These conduits may be configured in various ways to provide consistent cooling and temperature distribution within the window, such as a single inlet, a single outlet, and a single flow path with a serpentine section. Fluid may be flowed from a fluid source or reservoir external to the chamber through the pedestal and onto the window.

[0170] As shown in FIGS. 1 and 4 , the substrate support 108 of the pedestal 104 supports the substrate 118 above the window 150 and the substrate heater 122 and is configured to be offset from the window 150 and the substrate heater 122. In certain embodiments, the temperature of the substrate can be rapidly and accurately controlled by thermally floating or isolating the substrate within the chamber. Heating and cooling of the substrate is directed both to the thermal mass of the substrate and to the thermal mass of other items in contact with the substrate. For example, if the substrate is in thermal contact with a large object, such as the entire backside of the substrate resting on a large surface of the pedestal or an electrostatic chuck as found in many conventional etching apparatuses, this object acts as a thermal sink for the substrate, affecting the ability to accurately control the substrate temperature and reducing the rapidity of heating and cooling of the substrate. Therefore, it is desirable to position the substrate so that minimal thermal mass is heated and cooled. This thermal floating is configured to position the substrate so that it has minimal thermal contact (including direct and radiative) with other objects within the chamber.

[0171] Thus, in some embodiments, the pedestal 104 is configured to support the substrate 118 by thermally floating or isolating the substrate within the chamber interior 114. The multiple substrate supports 108 of the pedestal 104 are configured to support the substrate 118 such that the thermal mass of the substrate 118 is reduced as much as possible to the thermal mass of the substrate 118 alone. Each substrate support 108 may have a substrate support surface 120 that minimizes contact with the substrate 118. The number of substrate supports 108 may range from at least three to, for example, at least six or more. The surface area of ​​the support surface 120 may also be the minimum area required to adequately support the substrate (e.g., to support the weight of the substrate and prevent inelastic deformation of the substrate) during processing operations. In some embodiments, the surface area of ​​a single support surface 120 may be, for example, less than about 0.1%, less than about 0.075%, less than about 0.05%, less than about 0.025%, or less than about 0.01%.

[0172] The substrate support is also configured to prevent the substrate from contacting other elements of the pedestal, including surfaces and features of the pedestal below the substrate. As can be seen in Figures 1 and 4, the substrate support 108 holds the substrate 118 above and offsets it from the next adjacent surface of the pedestal 104 below the substrate 118, which is the top surface 152 of the window 150 (identified in Figure 4). As can be seen from these figures, a volume or gap exists below the substrate, excluding contact with the substrate support. As shown in Figure 4, the substrate 118 is offset from the top surface 152 of the window 150 by a distance 158. This distance 158 can affect the thermal effect on the substrate 118 due to the window 150. The greater the distance 158, the smaller the effect. It has been found that a distance 158 of 2 mm or less results in increased thermal coupling between the window and the substrate, so it is desirable to have the distance 158 greater than 2 mm, for example, at least about 5 mm, about 10 mm, about 15 mm, about 20 mm, about 30 mm, about 50 mm, or about 100 mm.

[0173] The substrate 118 is also offset from the substrate heater 122 by a distance 160 (as measured from the top surface of the substrate heater 122, which in some cases may be the top surface of the LEDs 124). This distance 160 affects many aspects of heating the substrate 118. In some cases, the LEDs 124 provide a non-uniform heating pattern that increases as the distance 160 decreases; conversely, this non-uniform heating pattern decreases by increasing the distance 160. In some cases, as the distance 160 increases, the heating efficiency decreases across the substrate, and more so at the edge regions, causing non-uniform heating of the substrate. In some embodiments, a distance 160 of about 10 mm to 90 mm, about 5 mm to 100 mm, including, for example, 10 mm to 30 mm, provides a substantially uniform heating pattern and acceptable heating efficiency.

[0174] As mentioned, the substrate supports 108 are configured to support the substrate 118 above the window. In some embodiments, these substrate supports are stationary and fixed in place; they are not lift pins or support rings. In some embodiments, at least a portion of each substrate support 108, including the support surface 120, may be composed of a material that is at least transparent to the light emitted by the LEDs 124. This material may, in some cases, be quartz or sapphire. The transparency of these substrate supports 108 may allow visible light emitted by the LEDs of the substrate heater 122 to pass through the substrate supports 108 and onto the substrate 118, so that the substrate supports 108 do not block this light and the substrate 118 can be heated in the supported region. This may result in more uniform heating of the substrate 118 than would be possible using substrate supports comprising a material that is opaque to visible light. In some other embodiments, the substrate supports 108 may be composed of a non-transparent material, such as zirconium dioxide (ZrO).

[0175] 4, the substrate support surface 108 may be positioned closer to the central axis 162 of the window 150 than the outer diameter 164 of the window 150. In some cases, a portion of these substrate supports may extend upwardly across the window 150 such that the support surface 120 is above the window 150 and the substrate supports overlap the window 150.

[0176] In some embodiments, the substrate supports may each include a temperature sensor configured to detect the temperature of a substrate positioned on the support surface of the substrate support. FIG. 5 shows the substrate support of FIGS. 1 and 4 according to a disclosed embodiment. Here, the support surface 120 of the substrate support 108 is identified along with a temperature sensor 166. In some embodiments, the temperature sensor 166 extends through the support surface 120 such that the temperature sensor 166 is in direct contact with a substrate held by the support surface 120. In some other embodiments, the temperature sensor 166 is positioned within the substrate support 108 below the support surface 120. In some embodiments, the temperature sensor 166 is a thermocouple. In some other embodiments, the temperature sensor 166 may be a thermistor, a resistance temperature detector (RDT), or a semiconductor sensor. Electrical wiring 168 for the temperature sensor 166 may run through the substrate support 108 and through the pedestal 104.

[0177] 1 , in some embodiments, the pedestal is also configured to move vertically. This may include moving the pedestal such that the gap 186 between the guard plate 176 of the gas distribution unit 110 and the substrate 118 can be in the range of 2 mm to 70 mm. As provided in more detail below, moving the pedestal vertically may enable active cooling of the substrate and rapid cycle times for processing operations, including flowing and purging gases, due to the low volume created between the gas distribution unit 110 and the substrate 118. This movement also allows for the creation of a small process volume between the substrate and the gas distribution unit, resulting in smaller purge and process volumes, which can reduce purge and gas transfer times and increase throughput.

[0178] The gas distribution unit 110 is configured to flow process gases, which may include liquids and / or gases, such as reactants, modifying, transforming, or removing molecules, over a substrate 118 in the chamber interior 114. As can be seen in FIG. 1 , the gas distribution unit 110 includes one or more fluid inlets 170 fluidly connected to one or more gas sources 172 and / or one or more vapor sources 174. In some embodiments, the gas lines and mixing chamber may be heated to prevent unwanted condensation of the vapors and gases flowing therethrough. These lines may be heated to at least about 40° C., at least about 80° C., at least about 90° C., at least about 120° C., at least about 130° C., or at least about 150° C. The one or more vapor sources may include one or more sources of vaporized gas and / or liquid. Vaporization may be by a direct injection evaporator, a flow-over evaporator, or both. The gas distribution unit 110 also includes a guard plate 176 that includes a plurality of through-holes 178 that fluidly connect the gas distribution unit 110 with the chamber interior 114. The through-holes 178 are fluidly connected to one or more fluid inlets 170 and extend through a front surface 177 of the guard plate 176, which is configured to face the substrate 118. In some embodiments, the gas distribution unit 110 may be considered a top plate, and in some other embodiments, it may be considered a showerhead.

[0179] The through-holes 178 may be configured in various ways to deliver a uniform gas flow onto the substrate. In some other embodiments, the through-holes may all have the same outer diameter, such as about 0.03 inches to 0.05 inches, including about 0.04 inches (1.016 mm). The through-holes may also be distributed throughout the entire protective plate to create a uniform flow from the protective plate.

[0180] 6 shows a plan view of a first exemplary protective plate 176, with the front surface 177 (the surface configured to face the substrate) and through-holes 178 visible. As shown, the through-holes 178 in the protective plate 176 extend through the protective plate 176 and the front surface 177. The through-holes are also arranged along multiple circles centered about the central axis of the protective plate, such that the holes are offset from one another. For example, the protective plate 176 may have a through-hole 178A centered about the central axis of the protective plate 176. Immediately adjacent to the central through-hole 178A may be a plurality of holes equally spaced along a first circle 179 having a first diameter, and immediately radially outward from this circle may be another circle 181 having a second plurality of holes having more holes than the first plurality of holes, and the second plurality of holes may be equally spaced along the second circle. This even spacing may not be precise and may be considered substantially evenly spaced, due to manufacturing or other inconsistencies, so that the spacing may be equal to within about + / - 5%. As shown, some circles of through holes 178 may be centered on a reference datum 183, while other circles of through holes are offset from the reference datum 183 by an angle, such as about 15°, 7.5°, etc. Here, the through holes along a first circle 179 are two through holes centered on the datum, and the through holes along a second circle are not centered on the reference datum 183 but are offset from the datum 183 by about 15°. The concentric through holes may alternate between holes centered on the datum 183 and holes offset from the datum 183.

[0181] FIG. 7 shows a plan view of a second exemplary protective plate 176 with the front surface 177 (the surface configured to face the substrate) and the through-holes 178 visible. As shown, the through-holes 178 in the protective plate 176 extend through the protective plate 176 and the front surface 177. The through-holes are arranged differently than in FIG. 6, with one through-hole 178 centered on the central axis of the protective plate 176 and six sectors of through-holes 178 arranged such that in each sector, the through-holes are equally spaced along the arcs within the sector. For example, one sector 191 is encompassed by a dashed line shape, and the holes are arranged along multiple arcs within the sector that increase with increasing radial distance from the center of the protective plate 176. A first exemplary arc 193A is identified along six equally spaced through-holes 178, and a second exemplary arc 193B is identified along twelve equally spaced through-holes. The second exemplary arc 193B has a radial distance R2 that is greater than the first exemplary arc 193A and greater than the radial distance R1 of the first exemplary arc 193A.

[0182] 1 , the gas distribution unit 110 may also include a unit heater 180 thermally connected to the guard plate 176 such that heat may be transferred between the guard plate 176 and the unit heater 180. The unit heater 180 may include a fluid conduit through which a heat transfer fluid may flow. As above, the heat transfer fluid may be heated, for example, to a temperature range of about 20°C to 120°C. In some cases, the unit heater 180 may be used to heat the gas distribution unit 110 to prevent unwanted condensation of vapors and gases, and in some such cases, this temperature may be at least about 90°C or 120°C.

[0183] In some embodiments, the gas distribution unit 110 may include a second unit heater 182 configured to heat the protective plate 176. This second unit heater 182 may include one or more resistive heating elements, fluid conduits for flowing heated fluid, or both. The use of two heaters 180 and 182 in the gas distribution unit 110 may enable various heat transfers within the gas distribution unit 110. This may include using the first and / or second unit heaters 180 and 182 to heat the protective plate 176 to provide a temperature-controlled chamber, as described above, to reduce or prevent unwanted condensation on the elements of the gas distribution unit 110.

[0184] The apparatus 100 may also be configured to cool the substrate. This cooling may include flowing a cooling gas over the substrate, moving the substrate near the protective plate to allow heat transfer between the substrate and the protective plate, or both. Actively cooling the substrate allows for more precise temperature control and faster transitions between temperatures, reducing processing time and improving throughput. In some embodiments, a first unit heater 180, which flows a heat transfer fluid through a fluid conduit, may be used to cool the substrate 118 by transferring heat transferred from the substrate 119 away from the protective plate 176. Thus, the substrate 118 may be cooled by positioning it in close proximity to the protective plate 176, with a gap 186 of 5 mm or less, or 2 mm or less, such that heat from the substrate 118 is radiatively transferred to the protective plate 176 and transferred away from the protective plate 176 by the heat transfer fluid in the first unit heater 180. Thus, the protective plate 176 may be considered a heat sink for the substrate 118 to cool the substrate 118.

[0185] In some embodiments, the apparatus 100 may further include a cooling fluid source 173, which may include a cooling fluid (gas or liquid), and a chiller (not shown) configured to cool the cooling fluid to a desired temperature, such as at least about 90° C. or less, at least about 70° C. or less, at least about 50° C. or less, at least about 20° C. or less, at least about 10° C. or less, at least about 0° C. or less, at least about −50° C. or less, at least about −100° C. or less, at least about −150° C. or less, at least about −190° C. or less, at least about −200° C. or less, or at least about −250° C. The apparatus 100 includes piping for delivering the cooling fluid to the one or more fluid inlets 170 and a gas distribution unit 110 configured to flow the cooling fluid over the substrate. In some embodiments, the fluid may be in a liquid state when flowed into the chamber 102 and may change to a vapor state upon reaching the chamber interior 114, for example, when the chamber interior 114 is at a low pressure, such as between about 0.1 Torr and 10 Torr, or between about 0.1 Torr and 100 Torr, or between about 20 Torr and 200 Torr, as described above. The cooling fluid may be an inert substance such as nitrogen, argon, or helium. In some cases, the cooling fluid may include or consist solely of a non-inert substance or mixture, such as hydrogen gas. In some embodiments, the flow rate of the cooling fluid into the chamber interior 114 may be, for example, at least about 0.25 liters / minute, at least about 0.5 liters / minute, at least about 1 liter / minute, at least about 5 liters / minute, at least about 10 liters / minute, at least about 50 liters / minute, or at least about 100 liters / minute. In certain embodiments, the apparatus may be configured to cool the substrate at one or more cooling rates, such as at least about 5°C / sec, at least about 10°C / sec, at least about 15°C / sec, at least about 20°C / sec, at least about 30°C / sec, or at least about 40°C / sec.

[0186] In some embodiments, the apparatus 100 may actively cool the substrate by both moving the substrate closer to the protective plate and by flowing a cooling gas over the substrate. In some cases, active cooling may be more effective by flowing the cooling gas while the substrate is in close proximity to the protective plate. The effectiveness of the cooling gas may also depend on the type of gas used. Figure 8 shows graphs of four different active cooling experiments. In these four experiments, different gases and gaps between the substrate and the protective plate were used to cool the substrate from about 400°C to about 25°C. In the first experiment, the substrate was positioned 2 mm from the protection plate and actively cooled at 400°C by flowing helium gas over the substrate ("He 2mm"); in the second experiment, the substrate was positioned 20 mm from the protection plate and actively cooled at 400°C by flowing helium gas over the substrate ("He 20mm"); in the third experiment, the substrate was positioned 2 mm from the protection plate and actively cooled at 400°C by flowing nitrogen gas over the substrate ("N2 2mm"); and in the fourth experiment, the substrate was positioned 20 mm from the protection plate and actively cooled at 400°C by flowing nitrogen gas over the substrate ("N2 20mm"). As shown, the first experiment cooled the substrate the fastest, at approximately 150 seconds, and the third experiment cooled the substrate the next fastest, at approximately 450 seconds. The first and third experiments used both cooling gas and a 2 mm gap, while the later second and fourth experiments used a 20 mm gap.

[0187] Thus, the apparatus provided herein can rapidly heat and cool a substrate. Figure 9 shows an exemplary temperature control sequence. At time 0, the substrate is at approximately 20 or 25°C, and the LEDs of the substrate heater provided herein emit visible light having a wavelength of 400 nm to 800 nm, raising the substrate temperature to approximately 400°C in approximately 30 seconds. This heating was achieved using 1 kW to 2 kW of heating power provided by an approximately 9 kW power supply to the substrate heater. From approximately 30 seconds to approximately 95 seconds, the substrate heater 122 maintained the substrate at 400°C using less power, such as 0.3 kW to approximately 0.5 kW of heating power provided by an approximately 2 kW power supply. For approximately 30 to 60 seconds, the substrate was actively cooled using both a cooling gas (e.g., hydrogen or helium) flowed over the substrate and heat transfer to the protective plate. Once cooled, the substrate heater heated the substrate using about 10-30 W of heating power provided by a power supply of about 100 W to maintain its temperature at approximately 70° C. Various processing techniques may use this type of sequence once or repeatedly to process the substrate.

[0188] In some embodiments, the apparatus 100 may include a mixing plenum for blending and / or conditioning process gases for delivery before reaching the fluid inlet 170. One or more mixing plenum inlet valves may control the introduction of process gases into the mixing plenum. In some other embodiments, the gas distribution unit 110 may include one or more mixing plenums within the gas distribution unit 110. The gas distribution unit 110 may also include one or more annular channels fluidly connected to the through-holes 178, which may evenly distribute received fluids to the through-holes 178 to provide a uniform flow over the substrate.

[0189] The apparatus 100 may also include one or more additional non-contact sensors for detecting the temperature of the substrate. One such sensor may be a novel pyrometer capable of detecting multiple temperature ranges of silicon substrates. For example, it is desirable to detect the temperature of substrates with different processes in different temperature ranges where processing operations may occur, such as below about 200°C, above about 200°C to below about 600°C, or above 600°C, whether the silicon is doped or undoped. However, some pyrometers are unable to detect different substrates within these ranges. Some pyrometers measure optical signals reflected or emitted by the surface of an object to determine the temperature of the object according to some calibration. However, many silicon wafers cannot be measured by these pyrometers because silicon is optically transparent at various temperatures and with various processes. As discussed above, Figure 13 shows the different absorptivities of substrates at various temperatures. For example, while some pyrometers can detect emissions in the range of about 8-15 microns, most silicon substrates, at least below about 200°C, do not have a consistent emission signal in the range of about 8-15 microns and are therefore undetectable by some pyrometers below about 200°C.

[0190] Lightly doped or undoped silicon substrates have emission signals of approximately 0.95 to 1.1 microns when the substrate is at or below about 300°C, doped silicon substrates have emission signals of approximately 1 to 4 microns when the substrate is below about 200°C, silicon substrates have emission signals of approximately 1 micron when the substrate is near room temperature, e.g., below about 100°C, including 20°C, and silicon substrates have emission signals of approximately 8 to 15 microns when the substrate is at temperatures above about 600°C. Thus, the new pyrometers are configured to detect multiple emission ranges to detect multiple substrates, e.g., doped, lightly doped, or undoped substrates, at various temperature ranges. This includes configurations for detecting emission ranges of about 0.95 microns to about 1.1 microns, about 1 micron, about 1 to about 4 microns, and / or about 8 to 15 microns. The new pyrometers are also configured to detect substrate temperature at shorter wavelengths to distinguish the signal from chamber thermal noise.

[0191] The novel pyrometer may include an emitter configured to emit infrared radiation and a detector configured to receive the emissions. Referring to FIG. 1 , the apparatus includes a novel pyrometer 188 having an emitter therein, and a detector 190. The novel pyrometer may be configured to emit a signal on one side, either the top or bottom, of the substrate and receive the signal on the other side of the substrate. For example, the emitter may emit a signal on the top of the substrate, and the detector is below the substrate and receives the signal emitted through the substrate below the substrate. Thus, the apparatus may have at least a first port 192A, such as port 192A through the center of the gas distribution unit 110, at the top of the chamber 102, and a second port 192B through the pedestal 104 and the substrate heater 122. An emitter in pyrometer 188 may be connected to one of ports 192A or 192B, such as first port 192A as shown in FIG. 1, via a fiber optic connection, and a detector is optically connected to the other port, such as second port 192B in FIG. 1. First port 192A may include a port window 194 to seal first port 192A from chemicals in chamber interior 114. Second port 192B can be seen in FIG. 1 to extend through pedestal 104 and substrate heater such that emitter emissions can pass through the substrate, through window 150, into second port 192B, and to detector 190, which may be located in the second port or optically connected to the second port through another fiber optic connection (not shown). In some other embodiments, the emitter and detector are reversed, such that the emitter emits through second port 192B and the detector detects through first port 192A.

[0192] The apparatus 100 may also include one or more optical sensors for detecting one or more metrics of the visible light emitted by the LEDs. In some embodiments, these optical sensors may be one or more photodetectors configured to detect the light and / or light intensity emitted by the LEDs of the substrate heater. In FIG. 1 , a single optical sensor 198 is shown connected to the chamber interior 114 via a fiber optic connection so that the optical sensor 198 can detect light emitted by the substrate heater 122. The optical sensor 198 and additional optical sensors may be positioned at various locations, for example, on the top and sides of the chamber 102, to detect light emitted at various locations within the chamber 102. As discussed below, this may enable measurement and adjustment of the substrate heater, such as adjustment of one or more independently controllable zones of the LEDs. In some embodiments, there may be multiple optical sensors 198 arranged along a circle or multiple concentric circles to measure various areas of the LEDs throughout the chamber 102. In some embodiments, the optical sensors may be positioned within the chamber interior 114.

[0193] In some embodiments, the apparatus may be further configured to generate plasma and use the plasma for some processes in various embodiments, which may include having a plasma source configured to generate plasma inside the chamber, such as capacitively coupled plasma (CCP), inductively coupled plasma (ICP), top remote plasma, and bottom remote plasma.

[0194] The devices described herein are not limited to ALE etching operations: they may be used with any etching technique.

[0195] Heat Treatment Technology Various techniques for using the apparatus described herein are now described. Figure 10 illustrates a first technique for thermal processing according to disclosed embodiments. In operation 1001, a substrate is provided to a chamber and thermally suspended within the chamber by positioning the substrate on pedestal substrate supports, with only the substrate supports in contact with the substrate and not with other elements of the processing chamber, as described above. Each substrate support contacts an edge region of the substrate, as provided herein and shown, for example, in Figures 1 and 4.

[0196] In operation 1003, the substrate is heated to a first temperature while thermally floating in the chamber, i.e., supported only by the substrate support, using a substrate heater described herein that emits visible light having a wavelength between 400 nm and 800 nm from a plurality of LEDs. The first temperature may be any temperature provided herein, including, for example, about 50°C to about 600°C, about 50°C to about 150°C, about 130°C, or about 150°C to 350°C. The substrate may be rapidly heated to the first temperature, for example, in less than about 60 seconds, less than about 45 seconds, less than about 30 seconds, or less than about 15 seconds. This may include powering the LEDs to their maximum power, which may be a combined delivered power of at least about 1 kW, at least about 2 kW, at least about 3 kW, at least about 4 kW, or at least about 9 kW or more. As provided herein, this heating does not include plasma or plasma generation.

[0197] In operation 1005, the substrate is maintained at a first temperature. This may include a substrate heater operating at a lower power to maintain the substrate at a particular temperature. Thus, the LEDs may be at a lower non-zero power level than during the temperature ramp-up to provide some heating and maintain the substrate at the desired temperature. Examples may include about 5 W to about 0.5 kW, including at least about 10 W, at least about 30 W, at least about 0.3 kW, or at least about 0.5 kW.

[0198] In operation 1007, the substrate is etched while at the first temperature. The etching may include flowing one or more gases to remove one or more modified layers of material. The etching does not include a plasma or plasma generation.

[0199] In operation 1009, which may be optional in some embodiments, the substrate is actively cooled. This active cooling may include flowing a cooling gas over the substrate, moving the substrate in close proximity to a protective plate, or both, as described herein. In some cases, this close proximity is 5 mm or less, including 2 mm. The cooling gas may also include, for example, helium and nitrogen. Following operation 1009, in some cases, operations 1003-1009 may be repeated, with each sequence being considered a cycle.

[0200] In some embodiments, operations 1003, 1005, and 1007 may also be performed while the chamber walls, protective plate, and / or the exterior surface of the pedestal are actively heated as described above. These items may be heated to between about 40° C. and about 150° C., including between about 80° C. and about 130° C., at least about 90° C., or at least about 120° C. Operations 1003, 1005, 1007, and 1009 may also be performed while the chamber interior is under vacuum, which may be at a pressure of between about 0.1 Torr and about 10 Torr, or between about 0.1 Torr and about 100 Torr, or between about 20 Torr and 200 Torr.

[0201] The techniques provided herein may make various adjustments to process conditions. In some embodiments, these adjustments may be based on various received measurements, such as substrate temperature and LED measurements. In other embodiments, these adjustments may be made in an open-loop manner based on empirical or calculated data. In some embodiments, the techniques may follow a sequence similar to that shown in FIGS. 9 and 10, for example. In other embodiments, the sequence may involve etching the substrate at a first temperature or part of an etch cycle, followed by a temperature ramp to a second, higher temperature where another etch cycle or another part of the same etch cycle is performed. The substrate may then be actively cooled, and the etch may be repeated on the same substrate or a new substrate.

[0202] 11 illustrates a second technique according to disclosed embodiments. Here, operations 1101-1107 are the same as operations 1001-1007. After the etching of operation 1007, the heater power is adjusted in operation 1113 to a different power than that used during the maintenance of operation 1005 to heat the substrate to a second, higher temperature, as provided in operation 1115. The temperature of the substrate may be maintained at this second temperature during another etching of the substrate, as indicated by operations 1117 and 1119. Following these operations, the substrate may be actively cooled in operation 1109. In some cases, the etching operations 1103-1109 may be repeated on the same substrate or on a different substrate.

[0203] In some embodiments, heating and maintenance operations may be based on empirical and measured data, such as empirically derived temperature drift of devices such as the pedestal window. As described above, the window may retain heat during processing and act as an independent heater for the substrate. Adjustments may be made to the substrate heater to account for this drift, such as reducing the overall power delivered to the LEDs of the substrate heater during maintenance and etching operations such as 1005, 1105, 1007, and 1107. These adjustments may be linear or nonlinear, such as stepped or curved. This may also include adjustments to only some of the LEDs, such as to one or more of the independently controlled zones. For example, the center of the window may generate the most heat over time because it may not be able to remove heat, while the edges of the window may generate the least heat because some of this heat is transferred to the pedestal. Thus, to maintain uniform heating, one or more independently controllable zones of LEDs in the center of the substrate heater may be lowered to account for the increased heat in the center of the window. This allows the heat generated by both the window and the substrate heater and the heat transferred to the substrate in the central region to be the same. Similarly, the one or more independently controllable zones of LEDs in the outer regions of the substrate heater may be lowered or kept the same to account for any additional heating due to the outer edges of the window.

[0204] In some embodiments, as described above, each LED may be individually controllable, and in some such embodiments, a single LED may be adjusted to emit more or less light than one or more other LEDs. This adjustment may be made to account for hot or cold spots on the substrate. For example, a spot on the wafer may be hotter or cooler than other portions of the substrate, and an LED below or in close proximity to that spot on the substrate may be adjusted to adjust the temperature of that spot. This may include decreasing the light emitted by an LED to lower the temperature of the spot, or increasing the light emitted by an LED to raise the temperature of the spot.

[0205] The techniques provided herein may also include feedback control loops for adjusting operating parameters, such as the power of one or more zones of LEDs. These feedback loops may be implemented during the heating, maintaining, and etching operations described herein. This may include determining the temperature at the edge and at one or more locations within the substrate using one or more of the sensors described herein and adjusting the substrate heater based on these measurements.

[0206] FIG. 12 illustrates a third technique according to disclosed embodiments. Here, operations 1201-1211 are the same as operations 1001-1011, except that the technique here measures the substrate temperature during one or more of these operations and adjusts the substrate heater based on these measurements. The temperature measurement is represented by operation 1221, and the adjustment(s) are represented by operation 1223. The adjustment to the substrate heater may include increasing or decreasing power to one or more of the independently controllable zones of LEDs, including all of the LEDs. For example, as described above with respect to FIG. 5, if a temperature sensor on the substrate support indicates that the substrate edge has reached or exceeded a first temperature during one or more of operations 1203, 1205, and 1207, the power delivered to all of the LEDs may be decreased to reduce the temperature of the substrate. This may indicate a determination that at least one of the sensors indicates that the temperature of the substrate has exceeded a particular threshold, such as exceeding a first temperature. In another example, only one of the substrate supports may indicate that the substrate temperature is greater than a first temperature, and adjustments may be made to an independently controllable LED zone around this one sensor to reduce heat delivered to that location as opposed to the entire substrate.

[0207] Similarly, the pyrometer described above may also detect the temperature of the substrate at a location on the substrate, such as the center of the substrate. This temperature measurement may also be used, alone or in combination with a temperature sensor in the substrate support, to adjust the substrate heater. For example, if the pyrometer indicates that the center of the substrate is higher than a first temperature, adjustments may be made to independently controllable LED zones around the center of the substrate, or to the entire substrate, to reduce the temperature of the substrate at this location. While these examples are made with respect to reducing the power of LEDs, adjustments are not limited to such examples; the power of one or more independently controllable LED zones may be adjusted to increase the temperature at one or more locations on the substrate.

[0208] Another technique may measure the light emitted by the LEDs and adjust one or more independently controllable LED zones based on the measurement. This may involve emitting visible light having a wavelength between 400 nm and 800 nm from the LEDs and measuring one or more metrics of the visible light emitted by the LEDs using one or more sensors configured to detect the visible light emitted from the LEDs. These sensors may include the photodetectors described above. Based on the measured visible light, the power of one or more LED zones may be adjusted.

[0209] controller In some embodiments, the apparatus described herein may include a controller configured to control various aspects of the apparatus to perform the techniques described herein. For example, referring back to FIG. 1 , the apparatus 100 includes a controller 131 (which may include one or more physical or logical controllers) communicatively coupled to and controlling some or all of the operation of the processing chamber. The system controller 131 may include one or more memory devices 133 and one or more processors 135. In some embodiments, the apparatus includes a switching system for controlling, for example, flow rates and durations, a substrate heating unit, a substrate cooling unit, loading and unloading of a substrate in the chamber, thermal floating of the substrate, and a process gas unit when the disclosed embodiments are performed. In some embodiments, the apparatus may have a switching time of up to about 500 ms, or up to about 750 ms. The switching time may depend on the flow chemistry, the selected recipe, the reactor architecture, and other factors.

[0210] In some embodiments, the controller 131 is part of an apparatus or system, and may be part of the examples described above. Such a system or apparatus may include semiconductor processing equipment, including a processing tool or tools, a chamber or chambers, a processing platform or platforms, and / or specific processing components (e.g., gas flow systems, substrate heating units, substrate cooling units, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after processing of semiconductor wafers or substrates. This electronics may be referred to as a “controller,” which may control various components or subparts of the system or systems. The controller 966 may be programmed to control any of the processes disclosed herein, such as delivery of process 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 rates, fluid delivery settings, position and motion settings, wafer transfer between tools and other transfer tools, and / or load locks connected or interfaced with a particular system, depending on the processing parameters and / or type of system.

[0211] Broadly, the controller 131 may be defined as an electronic device having various integrated circuits, logic, memory, and / or software to receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. 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). The program instructions may be instructions communicated to the controller in the form of various individual settings (or program files) that define operational parameters for performing a particular process on or for a semiconductor wafer or for a system. The operational parameters, in some embodiments, may be part of a recipe defined by a process engineer to accomplish one or more processing operations during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0212] In some implementations, the controller 131 may be part of or coupled to a computer that is integrated with, coupled to, or otherwise networked to the system, or a combination thereof. For example, the controller may reside in all or part of a “cloud” or fab host computer system, thereby enabling remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, examine the history of past manufacturing operations, examine trends or performance metrics from multiple manufacturing operations, and modify parameters of a current process, configure processing operations to follow a current process, or initiate a new process. In some examples, a remote computer (e.g., a server) may provide process recipes to the 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 from the remote computer to the system. In some examples, the controller 131 receives instructions in the form of data specifying parameters for each of the processing operations performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool the controller is configured to interface with or control. Thus, as described above, the controller 131 may be distributed, such as by including one or more separate controllers networked together and operating toward a common purpose, such as the processes and controls described herein. An example of a distributed controller for such purposes includes one or more integrated circuits on the chamber in communication with one or more remotely located integrated circuits (e.g., at the platform level or as part of a remote computer) that couple to control the processes on the chamber.

[0213] As noted above, depending on the process operation or operations being performed by the equipment, the controller 131 may communicate with one or more of other equipment circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools throughout the factory, a main computer, another controller, or tools used to transport materials to and from containers of wafers to and from tool locations and / or load ports within a semiconductor fabrication factory.

[0214] As noted above, the controller is configured to perform any of the techniques described above, which may include causing a substrate transfer robot to position a substrate in the chamber on a plurality of substrate supports and deliver power to the LEDs such that the LEDs emit visible light having a wavelength between 400 nm and 800 nm to heat the substrate to a first temperature, such as between 100°C and 600°C, and flowing an etchant gas into the chamber to etch the substrate. This may also include cooling the substrate by flowing a cooling gas over the substrate while the substrate is supported only by the plurality of substrate supports, and / or vertically moving the pedestal such that the substrate is offset a first non-zero distance from a protective plate of the gas distribution unit, thereby transferring heat from the substrate to the protective plate via non-contact radiation.

[0215] While the subject matter disclosed herein has been particularly described with reference to illustrated embodiments, it will be understood that various changes, modifications, and adaptations may be made based on this disclosure and are intended to be within the scope of the invention. It should be understood that the specification is not limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements that are within the scope of the claims.

[0216] It should be further understood that the above disclosure, while focusing on a particular exemplary implementation or implementations, is not limited to only the discussed examples, but may also apply to similar modifications and features, and such similar modifications and features are also deemed to be within the scope of the present disclosure. Also, for the avoidance of doubt, it should be understood that the above disclosure is directed to at least the following numbered implementations, as well as other implementations that are apparent from the above disclosure:

[0217] Implementation 1: An apparatus for semiconductor processing, the apparatus comprising: a process chamber including a chamber wall at least partially in contact with a chamber interior and a chamber heater configured to heat the chamber wall; a substrate heater positioned within the chamber interior and having a plurality of light emitting diodes (LEDs) configured to emit light having a wavelength in a range of 400 nanometers (nm) to 800 nm; a window positioned above the substrate heater, having a top surface and a bottom surface opposite the top surface facing the LEDs, the window comprising a material that transmits light having a wavelength in the range of 400 nm to 800 nm; and three or more substrate supports, each substrate being supported by a window. an apparatus comprising: a pedestal including a window and three or more substrate supports configured to support a substrate such that a substrate supported by the three or more substrate supports is offset a non-zero distance from the window; a gas distribution unit including a protective plate having a front surface partially in contact with the chamber interior, the protective plate having one or more fluid inlets and a plurality of through-holes fluidly connected to the one or more fluid inlets and the chamber interior; and a unit heater thermally connected to the protective plate such that heat can be transferred between the protective plate and the unit heater.

[0218] Implementation 2: The apparatus of implementation 1, wherein each substrate support comprises a material that is transparent to light having a wavelength in the range of 400 nm to 800 nm.

[0219] Implementation 3: The apparatus described in Implementation 1, wherein each of the three or more substrate supports comprises quartz.

[0220] Implementation 4: The apparatus of implementation 1, wherein the substrate support surface is positioned closer to the central axis of the window than the outer diameter of the upper surface of the window.

[0221] Implementation 5: An apparatus as described in Implementation 1, wherein each substrate support includes a temperature sensor configured to detect the temperature of a substrate positioned on the substrate support surface.

[0222] Implementation form 6: The device described in implementation form 5, wherein the temperature sensor is a thermocouple.

[0223] Implementation 7: The apparatus of implementation 1, wherein each substrate support surface is vertically offset from the LED by a distance of 1 millimeter to 100 millimeters.

[0224] Implementation 8: The device described in implementation 1, wherein the window comprises quartz.

[0225] Implementation 9: The device described in implementation 8, wherein the window further comprises a sapphire coating.

[0226] Implementation form 10: The device described in implementation form 1, wherein the window does not have a hole in the center.

[0227] Implementation form 11: The device described in implementation form 1, wherein the upper surface of the window is non-planar.

[0228] Implementation form 12: The device described in implementation form 1, wherein the bottom surface of the window is non-planar.

[0229] Implementation 13: The device described in implementation 1, wherein the bottom surface of the window is in contact with at least the first set of LEDs.

[0230] Implementation 14: An apparatus as described in Implementation 1, wherein the base further includes a sidewall, and the exterior region of the window is thermally connected to the sidewall so that heat can be transferred between the exterior region and the sidewall.

[0231] Implementation 15: The apparatus described in Implementation 1, wherein the substrate heater further includes a printed circuit board including a reflective material on which the LED is supported.

[0232] Implementation 16: An apparatus as described in implementation 1, wherein the base includes a bowl in which the substrate heater is positioned, and the bowl includes one or more sidewalls having an outer surface including a reflective material.

[0233] Implementation 17: An apparatus as described in Implementation 1, wherein the base is thermally connected to the LED so that heat can be transferred between the LED and the base cooler, and further includes a base cooler that includes at least one flow path within the base and is configured to flow a cooling fluid within the at least one flow path.

[0234] Implementation 18: The apparatus described in implementation 17, wherein the base further includes a base heater configured to heat one or more outer surfaces of the base.

[0235] Implementation 19: The apparatus described in implementation 18, wherein the pedestal heater is a resistive heater.

[0236] Implementation 20: The device described in implementation 1, wherein the base includes a fluid inlet and is configured to allow fluid to flow between the LED and the bottom surface of the window.

[0237] Implementation 21: The device described in implementation 1, wherein the base is configured to move vertically.

[0238] Implementation form 22: An apparatus as described in implementation form 1, wherein the base is configured to move vertically to create a vertical offset gap between the substrate support surface of the substrate support and the front surface of the protection plate of about 2 millimeters (mm) to about 70 mm.

[0239] Implementation 23: An apparatus as described in Implementation 1, wherein the first set of LEDs are arranged in a first circle having a first radius around the central axis of the substrate heater and spaced equally apart from each other, and the second set of LEDs are arranged in a second circle having a second radius around the central axis that is larger than the first radius and spaced equally apart from each other.

[0240] Implementation 24: The device described in Implementation 1, wherein a first set of LEDs are electrically connected to form a first electrical zone, a second set of LEDs are electrically connected to form a second electrical zone, and the first and second electrical zones are independently controllable.

[0241] Implementation 25: The device described in Implementation 1, wherein the plurality of LEDs includes more than approximately 1,000 LEDs, and the plurality of LEDs are grouped to create at least approximately 80 independently controllable electrical zones.

[0242] Implementation 26: The device described in implementation 25, wherein the plurality of LEDs includes more than approximately 5,000 LEDs.

[0243] Implementation 27: The device described in implementation 1, wherein each LED is configured to emit visible blue light.

[0244] Implementation 28: The device described in implementation 1, wherein each LED is configured to emit visible white light.

[0245] Implementation 29: The device described in implementation 1, wherein each LED uses approximately 1.5 watts or less at full output.

[0246] Implementation 30: The device described in implementation 1, wherein each LED uses approximately 4 watts or less at full output.

[0247] Implementation 31: The device described in implementation 1, wherein each LED is a chip-on-board LED.

[0248] Implementation 32: The device described in implementation 1, wherein each LED is a surface-mounted diode LED.

[0249] Implementation 33: The apparatus described in implementation 1, wherein the gas distribution unit further includes a second unit heater configured to heat the protective plate.

[0250] Implementation 34: The device described in implementation 33, wherein the second unit heater is a resistive heater.

[0251] Implementation 35: An apparatus as described in implementation 1, wherein the unit heater includes at least one flow path and is configured to flow a heat transfer fluid through the at least one flow path.

[0252] Implementation 36: The apparatus described in Implementation 1, further comprising a mixing plenum fluidly connected to and upstream of at least one of the one or more fluid inlets of the gas distribution unit.

[0253] Implementation 37: The device described in implementation 1, further including one or more sensors configured to measure one or more metrics of the visible light emitted by the LED.

[0254] Implementation 38: The device described in implementation 37, wherein one or more sensors are photodetectors.

[0255] Implementation 39: The device described in implementation 37, wherein the one or more metrics include light emitted by the LED.

[0256] Implementation 40: An apparatus as described in Implementation 1, further comprising a pyrometer having a detector and an emitter, wherein the gas distribution unit includes a port extending through the protective plate and including a sensor window, the emitter or detector being connected to the port and sensor window through an optical fiber cable, and the emitter or detector being positioned within the base and below the window.

[0257] Implementation 41: The device described in implementation 40, wherein the pyrometer is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, or about 1 to about 4 microns.

[0258] Implementation 42: The device described in implementation 40, wherein the pyrometer is configured to detect emissions having wavelengths of about 1 micron, about 1.1 microns, and about 1 to about 4 microns.

[0259] Implementation 43: The device described in implementation 40, wherein the sensor window is located in the central region of the protective plate.

[0260] Implementation 44: The apparatus of implementation 1, wherein the chamber wall comprises aluminum.

[0261] Implementation 45: The apparatus described in implementation 1, wherein the chamber wall comprises a plastic coating.

[0262] Implementation 46: The apparatus of implementation 1, wherein the chamber wall comprises a metal with an yttria coating.

[0263] Implementation 47: The apparatus of implementation 1, wherein the chamber wall comprises a metal with a zirconia coating.

[0264] Implementation 48: The apparatus of implementation 1, wherein the chamber wall comprises a metal or metal alloy with an aluminum oxide coating.

[0265] Implementation 49: The apparatus described in Implementation 1, further comprising a vacuum pump configured to create a vacuum inside the chamber, wherein the processing chamber is configured to operate at a pressure range of about 0.1 Torr to about 100 Torr.

[0266] Implementation 50: The device described in Implementation 1, further including a controller having a processor and one or more non-transitory memory devices storing instructions for causing the LED to emit visible light having a wavelength of 400 nm to 800 nm.

[0267] Implementation 51: An apparatus as described in implementation 50, further including a cooling gas source fluidly connected to one or more fluid inlets, and wherein the one or more non-transitory memory devices further store instructions for flowing the cooling gas over the substrate.

[0268] Implementation 52: An apparatus as described in implementation 51, wherein the pedestal is configured to move vertically, and the one or more non-transitory memory devices further store instructions for moving the pedestal vertically and offsetting the substrate from the protective plate by a non-zero gap of approximately 5 mm or less, and wherein cooling gas flows over the substrate while the substrate is offset from the protective plate by the non-zero gap.

[0269] Implementation 53: A method including: supporting a substrate in a processing chamber having chamber walls using only a pedestal having multiple substrate supports each in contact with an edge region of the substrate; heating the substrate to a first temperature while the substrate is supported only by the multiple substrate supports by emitting visible light from multiple light-emitting diodes (LEDs) below the substrate, the visible light having a wavelength between 400 nanometers (nm) and 800 nm; and etching a surface of the substrate while the substrate is supported only by the multiple substrate supports and while the substrate is at the first temperature.

[0270] Implementation 54: A method as described in Implementation 53, further comprising cooling the substrate while the substrate is supported only by the multiple substrate supports by one or more of flowing a cooling gas over the substrate and vertically moving the pedestal so that the substrate is offset from the protective plate of the gas distribution unit by a first non-zero offset distance, thereby transferring heat from the substrate to the protective plate through non-contact radiation.

[0271] Implementation 55: A method according to implementation 54, wherein cooling is achieved by both flowing a cooling gas and positioning the substrate at a first non-zero offset distance from the protective plate.

[0272] Implementation 56: A method according to implementation 55, wherein the first non-zero offset distance is 5 mm or less.

[0273] Implementation 57: A method according to implementation 54, wherein the cooling gas includes one or more of hydrogen and helium.

[0274] Implementation 58: A method according to implementation 53, further comprising heating the chamber walls to a second temperature while the substrate is supported only by the multiple substrate supports, and heating a protective plate of a gas distribution unit positioned above the substrate to a third temperature while the substrate is supported only by the multiple substrate supports, wherein etching is performed while the chamber walls are heated to the second temperature and the protective plate is heated to the third temperature.

[0275] Implementation 59: A method according to implementation 58, wherein the second temperature and the third temperature are between 30°C and 150°C.

[0276] Implementation 60: The method of implementation 53, wherein the supporting, heating, and etching are performed while the processing chamber is at a pressure between about 0.1 Torr and about 100 Torr.

[0277] Implementation 61: The method of implementation 53, wherein the supporting, heating, and etching are performed while the processing chamber is at a pressure between about 20 Torr and about 200 Torr.

[0278] Implementation 62: A method according to implementation 53, wherein the first temperature is between about 30°C and about 200°C.

[0279] Implementation 63: The method of implementation 53, wherein the first temperature is between about 100°C and about 500°C.

[0280] Implementation 64: A method according to implementation 53, further comprising measuring the temperature of the substrate using one or more temperature sensors, and adjusting the power of at least a first set of multiple LEDs during heating, maintenance, and / or etching based on this measurement.

[0281] Implementation 65: A method as described in Implementation 64, wherein the one or more temperature sensors include one or more of a temperature sensor within at least one of the substrate supports, and a pyrometer having an emitter configured to emit radiation onto the substrate and a detector configured to receive emissions from the substrate, the temperature of the substrate, and the detector configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, or about 1 to about 4 microns.

[0282] Implementation 66: A method according to implementation 65, wherein the emitter is configured to detect emissions having wavelengths of about 1 micron, about 1.1 microns, and about 1 to about 4 microns.

[0283] Implementation 67: A method according to implementation 65, wherein the one or more temperature sensors include both a temperature sensor in at least one of the substrate supports and a pyrometer.

[0284] Implementation 68: A method according to implementation 53, further comprising adjusting the power of at least a first set of a plurality of LEDs, heating the substrate to a second temperature by emitting visible light from the LEDs after the adjustment is made while the substrate is supported only by the plurality of substrate supports, and etching the bottom surface of the substrate while the substrate is supported only by the plurality of substrate supports and while the substrate is at the second temperature.

[0285] Implementation 69: A method according to implementation 68, further comprising measuring the temperature of the substrate using one or more temperature sensors, and wherein the adjustment is made at least in part based on this measurement.

[0286] Implementation 70: A method as described in implementation 69, wherein the one or more temperature sensors include one or more of a temperature sensor within at least one of the substrate supports, and a pyrometer having an emitter configured to emit radiation onto the substrate and a receiver configured to receive emissions from the substrate, the temperature of the substrate, and the detector configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, or about 1 to about 4 microns.

[0287] Implementation 71: A method according to implementation 70, wherein the emitter is configured to detect emissions having wavelengths of about 1 micron, about 1.1 microns, and about 1 to about 4 microns.

[0288] Implementation 72: A method according to implementation 70, wherein the one or more temperature sensors include both a temperature sensor in at least one of the substrate supports and a pyrometer.

[0289] Implementation 73: A method as described in implementation 53, wherein the support further includes supporting the substrate using only a plurality of substrate supports comprising a material that transmits visible light having wavelengths of 400 nm to 800 nm.

[0290] Implementation 74: A method including: emitting visible light from a plurality of light-emitting diodes (LEDs) in a processing chamber, the visible light having a wavelength between 400 nanometers (nm) and 800 nm; measuring one or more metrics of the visible light emitted by the LEDs using one or more sensors configured to detect the visible light emitted from the plurality of LEDs; and adjusting power of a first set of the plurality of LEDs based at least in part on the measurements, the first set including fewer LEDs than the plurality of LEDs.

[0291] Implementation 75: A method according to implementation 74, wherein the measuring further includes measuring visible light using a photodetector.

[0292] Implementation 76: A method as described in implementation 75, wherein the photodetector is external to the processing chamber and connected to a port in the processing chamber via a fiber optic cable.

[0293] Implementation form 77: A pedestal for use in a semiconductor chamber, the pedestal having a top surface and a bottom surface opposite the top surface, the pedestal including a window comprising a material that transmits visible light having a wavelength in the range of 400 nm to 800 nm, and three or more substrate supports, each substrate support comprising a material that transmits visible light having a wavelength in the range of 400 nm to 800 nm, the window, and the three or more substrate supports having a substrate support surface configured to support a substrate such that substrates supported by the three or more substrates are offset by a non-zero distance, and the three or more substrate supports having a temperature sensor configured to detect the temperature of a substrate positioned on the substrate support surface.

[0294] Implementation 78: The pedestal of implementation 77, wherein each of the three or more substrate supports comprises quartz.

[0295] Implementation 79: The pedestal of implementation 77, wherein the substrate support surface is positioned closer to the central axis of the window than the outer diameter of the window top surface.

[0296] Implementation 80: The base of implementation 77, wherein each temperature sensor is a thermocouple.

[0297] Implementation 81: The pedestal of implementation 77, wherein each substrate support surface is vertically offset from the window by a distance of 5 to 30 millimeters.

[0298] Implementation 82: A base as described in implementation 77, further including a substrate heater having a plurality of light-emitting diodes (LEDs) configured to emit visible light having a wavelength in the range of 400 nm to 800 nm.

[0299] Implementation form 83: A pedestal for use in a semiconductor chamber, the pedestal including: a substrate heater having a plurality of light-emitting diodes (LEDs) configured to emit visible light having a wavelength in the range of 400 nanometers (nm) to 800 nm; and a window having a top surface and a bottom surface opposite the top surface, the window including a material that transmits visible light having a wavelength in the range of 400 nm to 800 nm, wherein one or more of the top surface and the bottom surface is non-planar.

[0300] Implementation 84: The base of implementation 83, wherein both the top and bottom surfaces are non-planar.

[0301] Implementation 85: The base of implementation 83, wherein the bottom surface of the window is in contact with at least the first set of LEDs.

[0302] Implementation 86: A base as described in implementation 83, wherein the base further includes a sidewall, and the exterior region of the window is thermally connected to the sidewall so that heat can be transferred between the exterior region and the sidewall.

[0303] Implementation 87: The base of implementation 83, wherein the substrate heater further includes a printed circuit board including a reflective material on which the LED is supported.

[0304] Implementation 88: A pedestal as described in implementation 83, wherein the pedestal includes a bowl in which the substrate heater is positioned, the bowl including one or more sidewalls having an outer surface including a reflective material.

[0305] Implementation form 89: A base as described in implementation form 83, wherein the base is thermally connected to the LED so that heat can be transferred between the LED and the base cooler, and further includes a base cooler that includes at least one flow path within the base and is configured to flow a cooling fluid within the at least one flow path.

[0306] Implementation 90: The pedestal of implementation 89, wherein the pedestal further includes a pedestal heater configured to heat one or more exterior surfaces of the pedestal.

[0307] Implementation 91: The pedestal of implementation 90, wherein the pedestal heater is a resistive heater.

[0308] Implementation 92: The base of implementation 83, wherein the base includes a fluid inlet and is configured to allow fluid to flow between the LED and the bottom surface of the window.

[0309] Implementation 93: A base as described in implementation 83, wherein the first set of LEDs are arranged in a first circle having a first radius around the central axis of the substrate heater and spaced equally apart from each other, and the second set of LEDs are arranged in a second circle having a second radius around the central axis that is larger than the first radius and spaced equally apart from each other.

[0310] Implementation 94: A base as described in implementation 83, wherein a first set of LEDs are electrically connected to form a first electrical zone, a second set of LEDs are electrically connected to form a second electrical zone, and the first and second electrical zones are independently controllable.

[0311] Implementation 95: A base as described in implementation 83, wherein the plurality of LEDs includes more than approximately 1,000 LEDs, and the plurality of LEDs are grouped to create at least approximately 80 independently controllable electrical zones.

[0312] Implementation 96: The base of implementation 95, wherein the plurality of LEDs includes more than about 5,000 LEDs.

[0313] Implementation 97: A base as described in implementation 83, wherein each LED is configured to emit visible blue light.

[0314] Implementation 98: The base described in implementation 83, wherein each LED is configured to emit visible white light.

[0315] Implementation 99: The base of implementation 83, wherein each LED uses approximately 1.5 watts or less at full power.

[0316] Implementation 100: The base of implementation 83, wherein each LED uses approximately 4 watts or less at full power.

[0317] Implementation 101: The base of implementation 83, wherein each LED is a chip-on-board LED.

[0318] Implementation 102: The base of implementation 83, wherein each LED is a surface-mount diode LED.

[0319] Implementation 103: An apparatus comprising: a processing chamber including a chamber wall at least partially in contact with the chamber interior; a pedestal positioned within the chamber interior and configured to support a substrate; and a pyrometer having a detector and an emitter, wherein the processing chamber is above the pedestal and includes a port extending through a surface of the processing chamber including a sensor window, the emitter or detector being connected to the port and the sensor window through an optical fiber cable, the emitter or detector being positioned within the pedestal, and the pyrometer being configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, or about 1 to about 4 microns.

[0320] Implementation 104: The device described in implementation 103, wherein the pyrometer is configured to detect emissions having wavelengths of about 1 micron, about 1.1 microns, and about 1 to about 4 microns.

[0321] Implementation 105: The apparatus described in implementation 103, wherein the sensor window is located in a central region of the processing chamber.

[0322] Implementation 106: An apparatus as described in implementation 103, wherein the processing chamber includes a protective plate having one or more fluid inlets and a plurality of through holes fluidly connected to the one or more fluid inlets and the interior of the chamber, and further includes a gas distribution unit having a front surface at least partially in contact with the interior of the chamber, and the port extends through the front surface of the protective plate.

[0323] Implementation 107: The device described in implementation 103, further including one or more sensors configured to measure one or more metrics of the visible light emitted by the LED.

[0324] Implementation 108: The device described in implementation 107, wherein the one or more sensors are photodetectors.

[0325] Implementation 109: The device described in implementation 107, wherein the one or more metrics include light emitted by the LED.

[0326] Implementation 110: A method including: supporting a substrate in a processing chamber having chamber walls using only a pedestal having multiple substrate supports each in contact with an edge region of the substrate; heating the substrate to a first temperature while the substrate is supported only by the multiple substrate supports by emitting visible light from multiple light-emitting diodes (LEDs) below the substrate, the visible light having a wavelength of 400 nanometers (nm) to 800 nm; and cooling the substrate while the substrate is supported only by the multiple substrate supports by one or more of flowing a cooling gas over the substrate and vertically moving the pedestal so that the substrate is offset from a protective plate of a gas distribution unit by a first non-zero offset distance of 5 mm or less, thereby transferring heat from the substrate to the protective plate through non-contact radiation.

[0327] Implementation 111: A method according to implementation 110, wherein cooling is by flowing a cooling gas over the substrate.

[0328] Implementation 112: A method according to implementation 110, wherein the cooling is performed by positioning the substrate at a first non-zero offset distance from the protection plate.

[0329] Implementation 113: A method according to implementation 110, wherein cooling is achieved by both flowing a cooling gas and positioning the substrate at a first non-zero offset distance from the protective plate.

[0330] Implementation 114: A method according to implementation 110, wherein the cooling gas includes one or more of hydrogen and helium.

Claims

1. 1. An apparatus for semiconductor processing, said apparatus comprising: a processing chamber including a chamber wall at least partially in contact with a chamber interior and a chamber heater configured to heat the chamber wall; positioned within the chamber interior; a substrate heater having a plurality of light emitting diodes (LEDs) configured to emit light having a wavelength in the range of 400 nanometers (nm) to 800 nm; a window positioned above the substrate heater comprising a material that transmits light having wavelengths in the range of 400 nm to 800 nm; and a pedestal including three or more substrate supports, each having a substrate support surface that is vertically offset from the window, the pedestal configured to support a substrate such that the window and the substrates supported by the three or more substrate supports are offset by a non-zero distance.

2. 10. The apparatus of claim 1, An apparatus wherein each substrate support comprises a material that is transparent to light having a wavelength in the range of 400 nm to 800 nm.

3. 10. The apparatus of claim 1, An apparatus wherein each substrate support includes a temperature sensor configured to detect a temperature of a substrate positioned on the substrate support surface.

4. 10. The apparatus of claim 1, The apparatus wherein the top surface of the window is non-planar and / or the bottom surface of the window is non-planar.

5. 10. The apparatus of claim 1, the base further includes a sidewall; The apparatus, wherein the exterior region of the window is thermally connected to the sidewall such that heat can be transferred between the exterior region and the sidewall.

6. 10. The apparatus of claim 1, the pedestal includes a bowl in which the substrate heater is positioned; The apparatus, wherein the bowl includes one or more sidewalls having an exterior surface comprising a reflective material.

7. 10. The apparatus of claim 1, the pedestal is a pedestal cooler thermally connected to the LED such that heat can be transferred between the LED and the pedestal cooler; at least one flow channel within the pedestal; The apparatus further comprises a pedestal cooler configured to channel a cooling fluid through the at least one flow path.

8. The apparatus of claim 7 , wherein the pedestal further comprises a pedestal heater configured to heat one or more exterior surfaces of the pedestal.

9. 10. The apparatus of claim 1, the first set of LEDs are arranged in a first circle having a first radius about a central axis of the substrate heater and are equally spaced apart from one another; The apparatus, wherein a second set of LEDs are arranged in a second circle about the central axis having a second radius greater than the first radius and being equally spaced apart from one another.

10. 10. The apparatus of claim 1, the first set of LEDs are electrically connected to form a first electrical zone; the second set of LEDs are electrically connected to form a second electrical zone; The apparatus, wherein the first and second electrical zones are independently controllable.

11. 10. The apparatus of claim 1, further comprising a pyrometer having a detector and an emitter; the processing chamber includes a port including a sensor window; the emitter or the detector is connected to the port and the sensor window through a fiber optic cable; The apparatus, wherein the emitter or the detector is positioned within the base and below the window.

12. 12. The apparatus of claim 11, The apparatus, wherein the pyrometer is configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, and / or about 1 to about 4 microns.

13. 10. The apparatus of claim 1, 1. A gas distribution unit comprising: one or more fluid inlets; and a gas distribution unit including a protective plate having a front surface partially in contact with the chamber interior, the protective plate having a plurality of through holes fluidly connected to the one or more fluid inlets and the chamber interior; The apparatus further comprising a unit heater, the unit heater thermally connected to the protective plate such that heat can be transferred between the protective plate and the unit heater.

14. 1. A method comprising: supporting a substrate in a processing chamber having a chamber wall using only a pedestal having a plurality of substrate supports each in contact with an edge region of the substrate; heating the substrate to a first temperature by emitting visible light from a plurality of light emitting diodes (LEDs) beneath the substrate, while the substrate is supported only by the plurality of substrate supports, the visible light having a wavelength in the range of 400 nanometers (nm) to 800 nm; etching a surface of the substrate while the substrate is supported only by the plurality of substrate supports and while the substrate is at the first temperature.

15. 15. The method of claim 14, while the substrate is supported only by the plurality of substrate supports; flowing a cooling gas over the substrate; and The method further includes vertically moving the pedestal so that the substrate is offset a first non-zero offset distance from a protective plate of a gas distribution unit, thereby cooling by one or more of transferring heat from the substrate to the protective plate through non-contact radiation.

16. 15. The method of claim 14, heating the chamber walls to a second temperature while the substrate is supported only by the plurality of substrate supports; heating a protective plate of a gas distribution unit positioned above the substrate to a third temperature while the substrate is supported only by the plurality of substrate supports; The method wherein the etching is performed while the chamber walls are heated to the second temperature and the guard plate is heated to a third temperature.

17. 15. The method of claim 14, measuring the temperature of the substrate using one or more temperature sensors; and adjusting power of at least a first set of the plurality of LEDs during the heating, maintaining, and / or etching based on the measurement.

18. 18. The method of claim 17, The one or more temperature sensors a temperature sensor within at least one of the substrate supports; and a pyrometer comprising an emitter configured to emit radiation onto the substrate and a detector configured to receive emissions from the substrate, a temperature of the substrate, the detector configured to detect emissions having one or more wavelengths of about 1 micron, about 1.1 microns, and / or about 1 to about 4 microns.

19. 18. The method of claim 17, heating the substrate to a second temperature by emitting visible light from the LEDs after the conditioning has occurred while the substrate is supported only by the plurality of substrate supports; etching a bottom surface of the substrate while the substrate is supported only by the plurality of substrate supports and while the substrate is at the second temperature.

20. 1. A method comprising: emitting visible light from a plurality of light emitting diodes (LEDs) within the processing chamber, the visible light having a wavelength in the range of 400 nanometers (nm) to 800 nm; measuring one or more metrics of the visible light emitted by the LEDs using one or more sensors configured to detect the visible light emitted from the plurality of LEDs; and adjusting power of a first set of the plurality of LEDs based at least in part on the measurement, the first set including fewer LEDs than the plurality of LEDs.

21. 21. The method of claim 20, The method, wherein said measuring further comprises measuring said visible light using a photodetector.

22. 22. The method of claim 21, The method, wherein the photodetector is external to the processing chamber and connected to a port in the processing chamber via a fiber optic cable.

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