Wafer point heating with beam width modulation

Abstract

Embodiments of the present disclosure provide a thermal processing chamber including a substrate support, a first plurality of heating elements disposed above or below the substrate support, and a spot heating module disposed on the substrate support. A point heating module is used to provide localized heating of an area on a substrate disposed on a substrate support during processing. Local heating of the substrate changes the temperature profile, which in turn can be used to improve deposition uniformity. The shape of the beam spot produced by the spot heating module may be modified without changing the optical elements of the spot heating module.

Description

[0001] This application is a divisional application of the patent application for invention with the application date of May 14, 2019, the application number of 201980033939.9, and the invention title of "Wafer Spot Heating Using Beam Width Modulation". Technical Field

[0002] Embodiments of the present disclosure relate to apparatuses and methods for semiconductor substrate processing, and more particularly, to a heat treatment chamber using a spot heating module suitable for semiconductor substrate processing. Background Art

[0003] Semiconductor substrates are processed for a variety of applications, including the fabrication of integrated circuit devices and micro-devices. In one class of processing, the substrate is typically located on a pedestal within a processing chamber. The pedestal is supported by a support shaft that can rotate about a central axis to rotate the pedestal coupled to one end of the support shaft. Precise control of heating sources (e.g., multiple heating lamps disposed below and above the substrate) allows the substrate to be heated during substrate processing.

[0004] The temperature of the substrate and the uniformity of the substrate temperature during processing can affect the thickness uniformity of the material deposited on the substrate. The non-uniformity of the substrate temperature can be axially symmetric or axially asymmetric. When the pedestal rotates during processing, the axially symmetric non-uniformity of the substrate temperature can be reduced by zonal control of the heating sources. The axially asymmetric non-uniformity of the substrate temperature (e.g., the axially asymmetric non-uniformity caused by the structural non-uniformity of the pedestal or the support shaft (e.g., lift pins)) cannot be compensated for by zonal control of the heating sources because the source of the non-uniformity rotates with the pedestal and the substrate.

[0005] Despite the use of precise control of heating sources to heat the substrate, non-uniformities are still observed in the results of deposition processes performed in many existing apparatuses. Therefore, there is a need for methods to manage and reduce axially asymmetric temperature non-uniformities in thermal semiconductor processing chambers. Summary of the Invention

[0006] Embodiments of the present disclosure relate to apparatuses and methods for semiconductor substrate processing, and more particularly, to a heat treatment chamber suitable for semiconductor substrate processing. In one embodiment, the processing chamber includes: an outer shell; a substrate support disposed within the outer shell; an energy module disposed outside the outer shell and facing the substrate support; a support disposed outside the outer shell; and a spot heating module disposed on the support. The spot heating module includes: a holder; and a moving device coupled to the holder.

[0007] In another embodiment, the processing chamber includes: a housing; a substrate support disposed within the housing; an energy module disposed outside the housing and facing the substrate support; and a spot heating module disposed outside the housing. The spot heating module includes: a plurality of holders; and a plurality of moving devices, wherein each of the plurality of moving devices is coupled to a corresponding one of the plurality of holders.

[0008] In another embodiment, the processing chamber includes: a housing; a substrate support disposed within the housing; an energy module disposed outside the housing and facing the substrate support; and a spot heating module disposed on the support. The spot heating module includes: a pedestal; a holder disposed on the pedestal; a collimator disposed on the holder; and a moving device, wherein the moving device is disposed between the holder and the collimator. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] As a way to understand in detail the above features of the present disclosure, a brief summary of the present disclosure can be obtained by referring to the embodiments. A more specific description is given above, and some of the embodiments are illustrated in the drawings. However, it should be noted that the drawings only illustrate typical embodiments of the present disclosure and should not be regarded as a limitation of the scope, because the present disclosure allows other equivalent embodiments.

[0010] Figure 1 FIG. is a schematic cross-sectional side view of a processing chamber according to one embodiment.

[0011] Figure 2 FIG. is a schematic cross-sectional side view of a processing chamber according to another embodiment.

[0012] Figure 3 FIG. is a schematic side view of a spot heater according to one embodiment.

[0013] Figures 4A to 4B FIG. is a schematic top view of a spot heating module according to one embodiment.

[0014] Figures 5A to 5C FIG. is formed by one or more Figure 3 schematic view of the beam spot formed by the spot heaters.

[0015] Figures 6A to 6B FIG. is a schematic view of beam spots having different orientations relative to the movement of the substrate according to one embodiment.

[0016] Figure 7 FIG. is a schematic cross-sectional side view of a processing chamber according to another embodiment.

[0017] Figure 8Schematic cross-sectional side view of a processing chamber according to yet another embodiment.

[0018] Figure 9 Schematic cross-sectional side view of a processing chamber according to a further embodiment.

[0019] For ease of understanding, the same reference numerals are used to denote the same elements common to the drawings as much as possible. It is contemplated that elements disclosed in one embodiment can be advantageously used in other embodiments without further elaboration. Detailed embodiments

[0020] Embodiments of the present disclosure provide a heat treatment chamber comprising a substrate support, a first plurality of heating elements disposed above, below, or above and below the substrate support, and a spot heating module disposed on the substrate support. The spot heating module is configured to provide local heating of an area on a substrate disposed on the substrate support during processing. The local heating of the substrate changes the temperature distribution, which can in turn be used to improve deposition uniformity. The shape of the beam spot generated by the spot heating module can be modified without changing the optical elements of the spot heating module.

[0021] As used herein, a "substrate" or "substrate surface" refers to any substrate surface on which processing is performed. For example, depending on the application, the substrate surface can include silicon, silicon oxide, doped silicon, silicon germanium, germanium, gallium arsenide, glass, sapphire, and any other materials such as metals, metal nitrides, metal alloys, and other conductive or semiconductive materials. The substrate or substrate surface can also include dielectric materials such as silicon dioxide, silicon nitride, organosilicates, and carbon-doped oxide or nitride materials. The substrate itself is not limited to any particular size or shape. Although the embodiments herein are related to circular 200 mm or 300 mm substrates, other shapes such as polygons, squares, rectangles, curved or other non-circular workpieces can be used.

[0022] Figure 1Schematic cross-sectional side view illustrating a processing chamber 100 according to one embodiment. The processing chamber 100 may be a deposition or heat treatment chamber, such as a vapor phase epitaxy chamber. For example, the chamber of the processing chamber 100 may also be used to perform other heat treatments. The processing chamber 100 may be used to process one or more substrates. A substrate 102 is disposed in the processing chamber 100 for processing, and the processing may include depositing a material on the device side 150 of the substrate 102, heating the substrate 102, etching the substrate 102, or a combination of the above. The processing chamber 100 includes a spot heating module 171. The spot heating module 171 includes one or more spot heaters 170. The spot heating module 171 is used to heat one or more regions on the substrate 102 during processing. The one or more regions may be cold spots, for example, the positions where the lift pins 132 generate non-uniform heat application to the substrate 102. In one embodiment, the spot heater 170 is connected to an electromagnetic radiation source 103 via a corresponding optical fiber 101. A single electromagnetic radiation source 103 may be optically coupled to only one spot heater 170 through the optical fiber 101, or optically coupled to more than one spot heater 170. A plurality of optical fibers 101 may connect one electromagnetic radiation source 103 to a plurality of spot heaters 170, as shown in Figure 1 shown. In some embodiments, the electromagnetic radiation source 103 is directly disposed on the spot heater 170 instead of being coupled to the spot heater 170 through the optical fiber 101. The electromagnetic radiation source 103 may be a pulsed electromagnetic radiation source or a continuous wave (CW) electromagnetic radiation source.

[0023] The electromagnetic radiation source 103 can be a high-energy radiation source, such as a laser. Examples of laser sources that can be used include crystal lasers, laser diodes and arrays, and VCSELs. High-intensity LED sources can also be used, and collimators can be used to collimate the light emitted from the LED source to form a light beam. The wavelength of the emitted radiation can generally be in the ultraviolet, visible, and / or infrared spectra, from about 200 nm to about 900 nm, such as 810 nm, and the emitted radiation can be monochromatic, narrow-band, wide-band, or ultra-wide-band, such as white laser. The electromagnetic radiation source 103 emits high-intensity electromagnetic radiation, which is guided through the optical fiber 101 to the point heater 170. The point heater 170 directs the exit end of the optical fiber 101 towards a target location in the processing chamber 100, for example, towards the substrate 102 disposed on the base 106. The optically fiber 101 thus oriented generates a radiation beam towards the target location from the radiation emitted by the electromagnetic radiation source 103. The end of the optical fiber 101 can have one or more optical features, including lenses, faceted surfaces, diffusive surfaces, filters, and other coatings, to direct or regulate the electromagnetic radiation exiting the optical fiber. Alternatively, one or more optical elements can be coupled to the end of the optical fiber 101 in the point heater 170. Thus, the point heater 170 is configurable and interchangeable. The radiation beams from the electromagnetic radiation source 103 can have the same wavelength or different wavelengths. In one embodiment, the radiation beams have different wavelengths for heating different materials formed on the substrate 102.

[0024] As Figure 1 shown, the point heater 170 includes a collimator 190 held by a retainer 192. The collimator 190 is an optical element that collimates the radiation from one of the electromagnetic radiation sources 103, for example, by using appropriately designed lenses. The collimator 190 has a first end into which the radiation from the electromagnetic radiation source 103 is input, for example, by guiding the output of the laser source into the opening in the first end. The collimator 190 has a second end that has an opening for receiving the collimating optical assembly. In some embodiments, the laser or laser source can be directly mounted to the collimator 190 by inserting the beam exit portion of the laser into the first end of the collimator 190 such that the radiation emitted by the laser passes through the collimator 190 and exits through the second end (which can be a lens or a lens group) of the collimating optical assembly.

[0025] In some embodiments, the collimator 190 is replaced by the optical fiber 101 or the electromagnetic radiation source 103, and the retainer 192 directly holds the optical fiber 101 or the electromagnetic radiation source 103. The retainer 192 is disposed on the pedestal 194. The pedestal 194 includes a wedge 196 and a slider 198. The point heater 170 will be further described below.

[0026] The processing chamber 100 includes a housing 148 that includes a base 180 and a reflector 154 disposed on the base 180. The processing chamber 100 further includes a spacer 112 disposed on the base 180, a first housing 108 disposed on the spacer 112, a second housing 110 disposed on the base 180, a susceptor 106 disposed between the first housing 108 and the second housing 110, and an energy module 104 disposed within the processing chamber 100. In this case, the energy module 104 is disposed within the base 180. The energy module 104 heats the susceptor 106 and / or a substrate 102 disposed on the susceptor 106. In one embodiment, the energy module 104 is an array of radiant heating lamps, as Figure 1 shown in. As Figure 1 and Figure 2 shown, the energy module 104 can be located below the second housing 110 to irradiate the susceptor 106, and the susceptor 106 is between the substrate 102 and the energy module 104. As Figure 2 shown, the energy module 104 can be disposed on both sides of the susceptor 106 such that the susceptor 106 is between two energy modules 104. Although Figure 1 is shown with the energy module 104 on one side of the susceptor 106 (i.e., below the susceptor 106), the energy module 104 can be disposed on the other side of the susceptor 106, as Figure 2 shown (i.e., above the susceptor 106). The energy module 104 disposed above the first housing 108 is also positioned to irradiate the substrate 102.

[0027] Each energy module 104 can be independently controlled in zones (e.g., radially) to control the temperature of multiple zones of the substrate 102 as a processing gas or vapor passes over the surface of the substrate 102, thereby facilitating deposition of material onto the device side 150 of the substrate 102. Radial zoning allows control of deposition thickness uniformity by adjusting the local temperature at the reaction site to compensate for reactant concentration variations due to flow non-uniformities and edge-to-center reactant consumption. The zones are individually powered using separate power supplies or by power distribution control between the zones.

[0028] The substrate 102 is transferred into the processing chamber 100 and placed onto the susceptor 106 through the loading port 109 formed in the spacer 112. The susceptor 106 can be a disk-shaped substrate support as shown. In some embodiments, the susceptor 106 is replaced by an annular substrate support (not shown) that supports the substrate 102 from the edge of the substrate 102 to directly expose the backside of the substrate 102, so as to be heated by the energy module 104 disposed below the second housing 110. The susceptor 106 can be made of silicon carbide, silicon coated with silicon carbide, quartz coated with silicon carbide, or graphite coated with silicon carbide to absorb the radiant energy from the energy module 104 and direct the radiant energy to the substrate 102, thereby heating the substrate 102.

[0029] Although not shown, for example, if the susceptor 106 has features to reduce contact, portions of the substrate 102 can be raised above the susceptor 106. In these cases, the susceptor heats the substrate 102 by a combination of radiation and conduction. The ratio of radiative heating to conductive heating is determined by the proportion of the substrate area in direct contact with the susceptor surface. The distribution of the two different heating mechanisms can result in thermal non-uniformities that cannot be corrected by zonal control of the energy module 104.

[0030] The susceptor 106 is supported by a shaft or rod 118 coupled to the motion assembly 120. The motion assembly 120 includes a rotational actuator 122 that rotates the rod 118 about the longitudinal axis A of the processing chamber 100 perpendicular to the X-Y plane of the processing chamber 100 during operation, and the rod 118 rotates the susceptor 106. The motion assembly 120 also includes a linear actuator 124 to move the rod 118 along the longitudinal axis A of the processing chamber 100 in the Z direction (e.g., vertically) of the processing chamber 100, and the rod 118 moves the susceptor 106. During processing, the susceptor 106 is rotated about its center using the rotational actuator 122 to minimize the effects of thermal and process gas flow space anomalies within the processing chamber 100, thereby facilitating uniform processing of the substrate 102. The susceptor 106 rotates at a rate between about 5 RPM and about 100 RPM, for example between about 10 RPM and about 50 RPM, for example about 30 RPM.

[0031] The first housing 108 can be a dome, and the second housing 110 can also be a dome. Each of the first housing 108 and the second housing 110 transmits radiant energy from the energy module 104. The first housing 108, the second housing 110, and the spacer 112 disposed between the first housing 108 and the second housing 110 define an internal region 111 of the processing chamber 100. Each of the first housing 108 and / or the second housing 110 can be flat, convex, or concave. In some embodiments, each of the first housing 108 and / or the second housing 110 is transparent to the radiation of the radiant energy emitted from the energy module 104 (transmitting at least 95% of the radiant energy). In one embodiment, the first housing 108 and the second housing 110 are made of quartz.

[0032] The energy module 104 provides a total radiant power output between about 10 KW and about 60 KW, which can heat the semiconductor substrate to a temperature in the range of about 200 degrees Celsius to about 1600 degrees Celsius. Each lamp 105 of the energy module 104 can be coupled to a power distribution board, such as a printed circuit board (PCB) 159, through which power is supplied to each lamp 105. If one power supply supplies power to more than one heating zone, the PCB 159 can have a power distribution control circuit. In one embodiment, the energy module 104 is positioned within the housing 145. The housing 145 has one or more channels 149 for the flow of a cooling fluid between the lamps 105.

[0033] In Figure 1In [the figure], the susceptor 106 is shown in an elevated processing position. When the susceptor 106 is in the processing position, the susceptor 106 divides the internal region 111 of the processing chamber 100 into a processing gas region 136 above the susceptor 106 and a purge gas region 138 below the susceptor 106. For loading and unloading the substrate 102, the susceptor 106 moves to a transfer position to allow the lift pins 132 to contact the supports 134 disposed on the inner surface 113 of the second housing 110. The supports 134 are made of the same material as the second housing 110. The lift pins 132 are suspended in holes 107 formed through the susceptor 106. Each hole 107 extends from the substrate support surface 115 of the susceptor 106 to the rear surface 117 of the susceptor 106 opposite the substrate support surface 115. One or more thermal sensors 153 are used to determine the substrate temperature. The thermal sensors 153 are configured to sense the thermal radiation emitted by the rear surface 117 of the susceptor 106. The sensor 153 can be a pyrometer disposed in a port formed in the outer housing 145. Additionally or alternatively, one or more thermal sensors 153 directly sense the thermal radiation emitted by the device side 150 of the substrate 102. The sensor 153, or one or more controllers coupled to the sensor 153 to receive signals representative of the sensed radiation, determine the temperature from the sensed radiation. A reflector 154 is placed outside the first housing 108 to reflect the radiation radiating away from the substrate 102 and redirect the radiation back onto the substrate 102. In one embodiment, as Figure 2 shown in [the figure], the energy module 104 is coupled to the reflector 154. Retaining rings 156 disposed on the spacer 112 and the first housing 108 fix the reflector 154 to the first housing 108. The reflector 154 can be made of metal, such as aluminum or stainless steel. Sensors 153 can be disposed through the reflector 154 to receive radiation from the device side 150 of the substrate 102.

[0034] Processing gas supplied from a processing gas supply source 151 is introduced into the processing gas region 136 via a processing gas inlet 114 formed in the spacer 112. The spacer 112 has an outer surface 182 and an inner surface 184. The processing gas inlet 114 directs the processing gas across the device side 150 of the substrate 102. The processing position of the susceptor 106 and the substrate 102 thereon are adjacent to the processing gas inlet 114, allowing the processing gas to flow generally along a flow path 173 across the device side 150 of the substrate 102. The processing gas exits the processing gas region 136 (along a flow path 175) via a gas outlet 116 located in the spacer 112 and opposite the processing gas inlet 114. The gas outlet 116 is an opening formed in the spacer 112 that fluidly couples the vacuum pump 157 to the processing gas region 136. Removal of the processing gas via the gas outlet 116 is facilitated by the vacuum pump 157 coupled thereto.

[0035] Purified gas supplied from the purified gas source 162 is introduced into the purified gas region 138 via a purified gas inlet 164 formed in the spacer 112. During the film forming process, the susceptor 106 is positioned such that the purified gas flows substantially along the flow path 165 across the rear surface 117 of the susceptor 106. The purified gas exits the purified gas region 138 via the gas outlet 116 (along the flow path 166) and is exhausted from the processing chamber 100.

[0036] The above-described processing chamber 100 can be controlled by a processor-based system controller (such as the controller 147), as Figure 1 and Figure 2 shown. For example, the controller 147 is configured to control the flow of various precursors, process gases, and purified gas from the gas sources during different operations of the substrate processing sequence. The controller 147 can be configured to control the activation of the point heating module 171, predict the algorithm for activating the point heating module 171, and / or synchronize the operation of the point heating module 171 with substrate rotation, gas supply, lamp operation, or other processing parameters, and other controller operations. The controller 147 includes a programmable central processing unit (CPU) 152, an input control unit, and a display unit (not shown) that are operable with a memory 155 and a mass storage device and are coupled to various components of the processing chamber 100, such as a clock, cache, input / output (I / O) circuits, etc., to facilitate the control of substrate processing in the processing chamber 100. The controller 147 further includes a support circuit 158. To facilitate the control of the above-described processing chamber 100, the CPU 152 can be any form of a general-purpose computer processor that can be used in an industrial setting, such as a programmable logic controller (PLC), for controlling multiple chambers and sub-processors. The memory 155 is in the form of a computer-readable storage medium that contains instructions that, when executed by the CPU 152, facilitate the operation of the processing chamber 100. The instructions in the memory 155 are in the form of a program product, such as a program that implements the method of the present disclosure.

[0037] Figure 2 A schematic cross-sectional view of a processing chamber 200 is illustrated according to one embodiment. The processing chamber 200 is similar in some aspects to Figure 1 the processing chamber 100 shown in Figure 2As shown, an optical fiber 101 can connect an electromagnetic radiation source 103 to a point heater 170, or multiple optical fibers 101 can be used to connect more than one electromagnetic radiation source 103 to a point heater 170.

[0038] Figure 3 is a schematic side view of a point heater 170 according to one embodiment. As Figure 3 shown, the point heater 170 includes a collimator 190 held by a retainer 192. The collimator 190 can be a tubular member containing optical elements (such as lenses), and the retainer 192 can be a cylindrical object with a central opening to receive and fix the tubular collimator 190 at a desired position. The retainer 192 is disposed on a pedestal 194, and the pedestal 194 is disposed on a support 302. The pedestal 194 includes a wedge 196 and a slider 198. The slider 198 can be linearly moved on the support 302 using a positioning screw or an actuator. The slider 198 can include an actuator that can move the slider 198 during processing. The wedge 196 includes a surface 304 that contacts the retainer 192, and the surface 304 forms an angle A with a plane 306 that is substantially parallel to the major surface of the base, such as Figure 1 and Figure 2 the base 106 of the processing chamber 100 shown in.

[0039] The angle A of the wedge 196 can be adjusted by an actuator located in the wedge 196. The aiming of the point heater 170 can be achieved by selecting the angle A of the wedge 196 and by adjusting the position of the slider 198. Since the angle A of the wedge 196 and the position of the slider 198 can be adjusted by actuators, the substrate can be adjusted during processing (such as Figure 1The position of the beam spot on the substrate 102 as shown. The wedge 196, the slider 198, and the support 302 can be made of a material that is transparent to the radiation energy emitted from the electromagnetic radiation source 103 (transmitting at least 95% of the radiation energy of the radiation). In one embodiment, the wedge 196, the slider 198, and the support 302 are made of quartz. In some embodiments, openings are formed through the wedge 196, the slider 198, and the support 302 for allowing a beam (such as a laser beam) from the collimator 190 to pass through the wedge 196, the slider 198, and the support 302 to a target area on the substrate 102. The openings can be large enough to accommodate the movement of the surface 304 of the wedge 196 or the slider 198. The opening formed in the support 302 can be at least larger than the openings formed in the wedge 196 and the slider 198, so that the openings formed in the wedge 196 and the slider 198 are not blocked by any part of the support 302. In one embodiment, the opening formed in the support 302 is larger than the opening in the slider 198 regardless of the position of the slider 198. In the case where the wedge 196 has an opening, the opening will be aligned with the optical axis of the radiation source that transmits radiation inside the collimator 190 (i.e., the optical fiber 101), and will be sized to allow all or the desired portion of the radiation to pass through the opening.

[0040] The spot heater 170 can be aimed by performing a manual alignment process. During the alignment process, any components between the support 302 and the base 106 can be removed to facilitate the manual alignment of the spot heater 170. The spot heater 170 is powered on to generate a guiding beam, so that the operator can observe the light spot from the guiding beam hitting the base. The base can be rotated so that the area heated by the spot heater 170 can be easily illuminated by the guiding beam. Then, the positioning devices (such as the wedge 196 of the slider 198 and the pedestal 194) can be operated to align the spot heater 170 with the area to be heated. In one embodiment, the area to be heated is the position where the lift pin is located, such as Figure 1 the lift pin 132 of the processing chamber 100 as shown in

[0041] The mobile device 308 is coupled to the collimator 190 to facilitate the movement of the collimator 190. The mobile device 308 is disposed between the holder 192 and the collimator 190. One or more bearings may be disposed between the mobile device 308 and the holder 192 to minimize the friction between the mobile device 308 and the holder 192. In one embodiment, the mobile device 308 is a device that can rotate the collimator 190 relative to the longitudinal axis 310 of the collimator 190. The collimator 190 can be located at a first position during the processing of the substrate using a first processing recipe, and the collimator 190 can be rotated to a second position before processing the substrate using a second processing recipe. The rotation of the collimator 190 can change the shape and / or size of the beam spot of the radiation beam exiting the collimator 190.

[0042] In one embodiment, during processing, the mobile device 308 continuously rotates the collimator 190 in one direction (clockwise or counterclockwise) relative to the longitudinal axis 310 of the collimator 190 to dynamically change the shape of the beam spot on the substrate. The substrate can also be rotated during processing. The rotation of the collimator 190 can be synchronized with the rotation of the substrate to provide precise heating of one or more cold spots on the substrate. In another embodiment, the mobile device 308 oscillates the collimator 190 to rotate within a predetermined angular range, for example, between -60 degrees and 60 degrees. The oscillation of the collimator 190 can be synchronized with the rotation of the substrate. In some embodiments, the collimator 190 is replaced by the optical fiber 101 or the electromagnetic radiation source 103 ( Figure 1 ). The mobile device 308 is coupled to the optical fiber 101 or the electromagnetic radiation source 103 held by the holder 192 ( Figure 1 ), and the mobile device 308 rotates the optical fiber 101 or the electromagnetic radiation source 103 in the same manner as rotating the collimator 190.

[0043] The mobile device 308 can be a controlled motion device that generates periodic motion, such as vibration, circular motion, or linear motion. The motion generated by the mobile device 308 is transmitted to the collimator 190, or alternatively, transmitted to the optical fiber 101 or the electromagnetic radiation source 103 ( Figure 1 ). The collimator 190 can move the beam spot by moving the collimator 190 along with the motion transmitted from the mobile device 308, and the movement of the beam spot irradiates an exposure area larger than the area of the beam spot. In another embodiment, the collimator 190 irradiates an overlapping area on the substrate, approximating the irradiation of a large beam spot larger than the beam spot generated by the electromagnetic radiation source 103 ( Figure 1 ). When the collimator 190 moves, the electromagnetic radiation source generates a continuous electromagnetic radiation beam, and when the electromagnetic radiation beam passes through the moving collimator 190, the continuous electromagnetic radiation beam irradiates an exposure area on the substrate larger than the area of the beam spot. The large beam spot defines an annular heating zone when the substrate rotates.

[0044] When an electromagnetic radiation beam passes through the movable collimator 190, the electromagnetic radiation source 103 can be pulsed via the movable collimator 190 to form a large beam spot on the substrate. As the substrate rotates, the large beam spot heats discrete areas on the substrate. The pulses of the electromagnetic radiation beam can be synchronized with the rotation of the substrate and / or the movement of the beam spot. For example, the pulses of the beam can be set to a frequency related to the vibration frequency of the collimator 190. The related frequency can transfer the radiation pulses to overlapping areas of the substrate such that the exposed area of the substrate (larger than the area of any single pulse) is exposed to pulsed radiation. The pulse duration of the movable collimator 190 determines the angular scan of the exposure along the annular or partial-annular heating zone.

[0045] The collimator 190 can move continuously or periodically, such as when the pulses of the electromagnetic radiation beam pass through the collimator 190. In one example, when the collimator 190 is moving, the beam can be pulsed for a first duration, and when the collimator 190 is not moving, the beam can be pulsed for a second duration. In this embodiment, the first exposed area of the substrate corresponding to the first duration is larger than the area of the beam, while the second exposed area corresponding to the second duration has the same dimensions as the size of the beam.

[0046] Figures 4A to 4B FIG. is a schematic top view of the point heating module 171 according to one embodiment. As Figure 4A shown, the point heating module 171 includes one or more point heaters 170. The one or more point heaters 170 are disposed on a support 302, and the support 302 is integrated into or on the chamber lid 402. The chamber lid 402 can be the reflector 154 or 254 of the processing chamber 100 or 200 as Figure 1 and Figure 2 shown. Each point heater 170 includes a pedestal 194 disposed on the support 302. Each point heater 170 can further include a collimator 190 disposed on the pedestal 194. One or more sensors 408 (such as pyrometers) are disposed on the support 302. In some embodiments, each point heater 170 includes a collimator 190 and a sensor 408, and both the collimator 190 and the sensor 408 are disposed on a single pedestal 194, as Figure 4B shown.

[0047] One or more sensors 408 can be used to modulate the power supplied to the point heater 170. For example, a controller (not shown) can receive temperature data from the sensor 408 and can increase or decrease the power supplied to the point heater 170 based on the temperature data. In this system, the combination of the sensor 408 and the point heater 170 can be used for closed-loop or open-loop control to adjust the point heater 170 based on the readings from the sensor 408.

[0048] The embodiments described herein can adjust the point heating of a substrate by adjusting the shape and / or size of the heating radiation point. The point heater 170 is configured to dynamically control the shape and / or size of the beam spot without modifying the optical elements of the system.

[0049] Figures 5A to 5C FIG. is a schematic view of a beam spot formed by one or more point heaters 170 described herein. As Figure 5A shown, the beam spot 502 is formed by one point heater 170 ( Figure 3 ). The beam spot 502 can be modified without changing the optical elements of the point heater 170. For example, as Figure 5B shown, the beam spot 504 is formed by two point heaters 170 ( Figure 1 ). The two point heaters 170 are positioned such that the beam spots generated by the point heaters 170 overlap. The two point heaters 170 can include electromagnetic radiation sources 103 that generate radiation beams of the same or different wavelengths. In one embodiment, the two point heaters 170 include a blue laser and a green laser, respectively, and the beam spot 504 includes a blue portion and a green portion. Alternatively, the beam spot 504 can be formed by moving the collimator 190 ( Figure 3 ). In another embodiment, the beam spot 504 is formed by actuating (e.g., vibrating) the slider 198 ( Figure 3 ). In yet another embodiment, the beam spot 504 is formed by actuating (e.g., moving) the angle A of the wedge 196 ( Figure 3 ). The movement of the collimator 190, the slider 198, or the angle A of the wedge 196 forms a racetrack-shaped beam spot 506, as Figure 5C shown. In one embodiment, a pair of wedges 196 are machined at a certain offset angle to respectively achieve the Figure 5B , 5C shown beam spots 504, 506.

[0050] Figures 6A to 6B FIG. is a schematic view of moving beam spots with different orientations relative to a substrate according to one embodiment. As Figure 6A shown, the beam spot 602 has an elliptical shape. The major axis of the elliptical beam spot 602 can be oriented substantially perpendicular to the direction of substrate movement, as indicated by the arrow 604. When the major axis of the beam spot 602 is substantially perpendicular to the direction of substrate movement, the width of the beam spot 602 (i.e., the effective length of the major axis of the beam spot 602) can be adjusted without changing the optical elements of the point heater 170. For example, the width of the beam spot 602 can be changed by rotating the collimator 190 ( Figure 3 ). As Figure 6BAs shown, rotation of the collimator 190 causes the beam spot 602 to rotate directionally, such that the major axis of the elliptical beam spot 602 is no longer substantially perpendicular to the direction of substrate movement, resulting in a narrower width of the beam spot 602. This technique is also applicable to linear beam spots.

[0051] Figure 7 FIG. is a schematic cross-sectional side view of a processing chamber 700 according to one embodiment. The processing chamber 700 is similar in some aspects to Figure 1 and Figure 2 the processing chamber 100 shown in. The processing chamber 700 is configured to process one or more substrates, including depositing material on the device side 722 of the substrate 710. The processing chamber 700 includes a first housing 712, a second housing 714, and a substrate support 702 disposed between the first housing 712 and the second housing 714. The first housing 712 and the second housing 714 may be made of the same material as Figure 1 the first housing 108 and the second housing 110 shown in.

[0052] The substrate support 702 includes a support ring 724 for supporting the substrate 710 and a ring support 726 for supporting the support ring 724. The substrate 710 is transferred into the processing chamber 700 via a load port 728 and positioned on the support ring 724. The support ring 724 may be made of graphite coated with SiC. The ring support 726 is rotated by a motor (not shown), thereby rotating the support ring 724 and the substrate 710.

[0053] The processing chamber 700 includes a first energy module 706 (e.g., radiant heating lamp) disposed below the second housing 714 for heating the substrate 710 from below the substrate 710. The processing chamber 700 also includes a second energy module 704 (e.g., radiant heating lamp) disposed on the first housing 712 for heating the substrate 710 from above the substrate 710. In one embodiment, the first and second energy modules 704, 706 provide infrared light radiant heat to the substrate via the first housing 712 and the second housing 714, respectively. The first and second housings 712, 714 are transparent to the radiation of the radiant energy emitted from the energy modules 704, 706 (transmitting at least 95% of the radiant energy). In one embodiment, the processing chamber 700 also includes one or more temperature sensors 730, such as an optical pyrometer, for measuring the temperature inside the processing chamber 700 and on the device side 722 of the substrate 710. One or more temperature sensors 730 are disposed on a support member 732, and the support member 732 is disposed on the cover 716. A reflector 718 is placed outside the first housing 712 to reflect the infrared light radiated from the substrate 710 and the first housing 712 back toward the substrate 710.

[0054] The spot heating module 171 is disposed on the support member 732. The spot heating module 171 includes one or more spot heaters 170. Each spot heating module 171 generates one or more electromagnetic radiation beams 734, such as high-energy electromagnetic radiation beams, such as laser beams, and each beam forms or contributes to a beam spot on the device side 722 of the substrate 710 to perform local heating of the substrate 710. Wherein the spot heating module 171 is located above the reflector 718, the electromagnetic radiation beam 734 passes through the opening 720 formed in the annular portion 736 of the reflector 718, and the first housing 712 is transparent to the radiation of the electromagnetic radiation beam 734 (transmitting at least 95% of the received radiation of the radiation beam 734).

[0055] During the epitaxial operation performed in the chamber 700, the substrate 710 is heated to a predetermined temperature, such as less than about 750 degrees Celsius. To improve the temperature uniformity of the substrate, the spot heating module 171 is used to locally heat one or more regions on the substrate 710. Since the substrate 710 rotates during operation, the local heating of the spot heating module 171 can occur on an annular region at a certain radius of the substrate 710.

[0056] The temperature sensor 730 can be used to modulate the power supplied to the spot heating module 171. For example, a controller (not shown) can receive temperature data from the temperature sensor 730 and increase or decrease the power supplied to the spot heating module 171 based on the temperature data. In this system, the combination of the temperature sensor 730 and the spot heating module 171 can be used for closed-loop or open-loop control to adjust the spot heating module 171 based on the readings from the temperature sensor 730.

[0057] Figure 8 FIG. is a schematic cross-sectional side view of a processing chamber 800 according to another embodiment. The processing chamber 800 is similar in some aspects to Figure 1 the processing chamber 100 shown in. The processing chamber 800 generally can have the shape of a rectangular box. The processing chamber 800 includes a first housing 802, a second housing 804, and a region 803 defined by the first and second housings 802, 804. The first housing 802 and the second housing 804 can be made of the same material as Figure 1 the first housing 108 and the second housing 110 shown in. In Figure 8 the embodiment of, the first and second housings 802 and 804 are flat and made of quartz that is transparent to the wavelength of the energy to be passed through to heat the substrate.

[0058] The first energy module 810 is disposed on the first housing 802. The first energy module 810 can be a plurality of radiant heat sources, such as elongated tubular radiant heating elements. The energy modules 810 are disposed in a spaced-apart parallel relationship and also extend substantially parallel to the reaction gas flow path (shown by arrow 812) through the processing chamber 800. The second energy module 815 is positioned below the second housing 804 and is oriented transversely to the first energy module 810. A plurality of point heat sources 820 supply concentrated heat to the underside of the substrate support structure (described below) to counteract the heat sink effect produced by the cold support structure extending through the bottom of the processing chamber 800.

[0059] The point heating module 171 is disposed on the cover 806 located on the first energy module 810. The point heating module 171 includes one or more point heaters 170. The point heating module 171 generates one or more electromagnetic radiation beams to perform local heating of the substrate disposed in the processing chamber 800. As is known in the art of semiconductor processing facilities, the power of the various heat sources 170, 810, 815, 820 can be controlled independently or in grouped partitions in response to the substrate temperature measured via temperature sensors.

[0060] The illustrated substrate 825 is supported by a substrate support 830 disposed in the region 803. The substrate support 830 includes a substrate holder 832 and support legs 834, and the substrate 825 is placed on the substrate holder 832. The legs 834 are mounted to a shaft 836 that extends downwardly through a tube 838 that extends through the chamber bottom 808. The tube 838 is in communication with a purge gas source, and the purge gas can flow through the tube 838 during the processing of the substrate 825.

[0061] A plurality of temperature sensors are placed near the substrate 825. The temperature sensors can take various forms, such as optical pyrometers or thermocouples. In the illustrated embodiment, the temperature sensors include thermocouples, including a first or central thermocouple 840 suspended below the substrate holder 832 in any suitable manner. The central thermocouple 840 passes near the substrate holder 832 through the legs 834. The processing chamber 800 further includes a plurality of secondary or peripheral thermocouples also near the substrate 825, the plurality of secondary or peripheral thermocouples including a front edge or front thermocouple 845, a trailing edge or rear thermocouple 850, and side thermocouples (not shown). Each peripheral thermocouple is disposed within a slip ring 852 that surrounds the substrate holder 832 and the substrate 825. The slip ring 852 is disposed on a support member 854 that extends from a front chamber divider 856 and a rear chamber divider 858. The dividers 856, 858 are made of quartz. Each of the central and peripheral thermocouples is connected to a temperature controller that sets the power of the various heat sources 810, 815, 820 in response to the temperature readings from the thermocouples.

[0062] The processing chamber 800 further includes an inlet port 860 for injecting reactants and carrier gases, and can also receive the substrate 825 through the inlet port 860. An outlet port 864 is located on the opposite side of the processing chamber 800, and the substrate support structure 830 is located between the inlet 860 and the outlet 864. The inlet member 865 is assembled to the processing chamber 800, adapted to surround the inlet port 860, and includes a horizontally elongated slot 867 through which the substrate 825 can be inserted. The substantially vertical inlet 868 receives gases from a gas source and communicates these gases with the slot 867 and the inlet port 860. The outlet member 870 is similarly mounted to the processing chamber 800 such that the exhaust opening 872 is aligned with the outlet port 864 and leads to an exhaust duct 874. The exhaust duct 874 can in turn be connected to a suitable vacuum member (not shown) for exhausting the processing gases from the processing chamber 800.

[0063] The processing chamber 800 also includes an excitation material source 876 located below the chamber bottom 808. The excitation material source 876 can be a remote plasma generator disposed along a gas line 878. A precursor gas source 880 is coupled to the gas line 878 for introduction into the excitation material source 876. A carrier gas source 882 is also coupled to the gas line 878. One or more branch lines 884 can also be provided for additional reactants. The excitation material source 876 can be used for plasma enhanced deposition, but can also be used to excite an etch gas species to clean excess deposited material in the processing chamber 800 when there is no substrate in the processing chamber 800.

[0064] Figure 9 FIG. is a schematic cross-sectional side view of a processing chamber 900 according to yet another embodiment. The processing chamber 900 includes a point heating module 171. The processing chamber 900 can be used to implement the methods described herein. An exemplary processing chamber 900 is a VULCAN ® chamber, available from Applied Materials, Inc., Santa Clara, California.

[0065] The processing chamber 900 includes a chamber body 902. The chamber body 902 defines an internal volume 904 of the chamber 900. The processing chamber 900 includes a substrate support 906 disposed within the internal volume 904. The substrate support 906 supports the substrate 901 on its periphery. In one embodiment, the substrate support 906 is located on a rotatable cylinder 925 that is magnetically coupled to a rotatable flange 926. The substrate 901 is oriented such that the surface 910 of the substrate 901 faces the transparent quartz window 914. When transferring the substrate 901 between a substrate transporter that brings the substrate 901 into the processing chamber 900 via an opening 948 and onto the substrate support 906, the lift pins 916 can be raised and lowered to support the substrate 901.

[0066] The processing chamber 900 further includes a radiative heating device 918 located below the window 914. The radiative heating device 918 directs radiative energy toward the substrate 901 to heat the substrate 901. The radiative heating device 918 includes a plurality of lamps 920 disposed within reflective tubes 922 arranged in a closely packed arrangement.

[0067] The spot heating module 171 is disposed on a cover 908 located on the substrate support 906. The spot heating module 171 includes one or more spot heaters 170. The spot heating module 171 generates one or more electromagnetic radiation beams to perform local heating of the substrate 901 disposed within the processing chamber 900. As is known in the art of semiconductor processing facilities, the power of the various heat sources 170, 918 can be controlled independently or in groups in response to the substrate temperature measured via temperature sensors (e.g., one or more thermal sensors 153).

[0068] The embodiments described herein provide a processing chamber that includes a spot heating module for providing local heating of a substrate during processing. During rotation of the substrate within the chamber, energy can be focused to a specific location to locally heat and regulate a specific location of the substrate, e.g., a location adjacent to a lift pin, at specific time intervals. In some cases, the spot heating elements can be positioned to specific locations by measuring the deposition thickness profile of a test substrate, finding the locations on the test substrate that would benefit from spot heating, marking these locations on the test substrate, reinserting the test substrate into the chamber, and using the positioning functions described herein (steering beam and positioning adjustment) to direct the spot heating to the marked locations. Then, subsequent substrates can be spot heated by the targeted spot heating elements to address non-uniformities in system processing. The beam spots generated by the spot heating module can be modified without changing the optics of the spot heating module.

[0069] While the foregoing relates to embodiments of the present disclosure, other and further embodiments of the present disclosure may be made without departing from the basic scope thereof, and the scope of the present disclosure is determined by the appended claims.

Claims

1. A processing chamber, comprising: a chamber body that at least partially defines an internal volume; a substrate support disposed within the chamber body; an energy module disposed outside the housing and facing the substrate support; one or more point heaters operable to emit energy into the internal volume; one or more sensors operable to measure parameters within the internal volume; a controller operable to increase or decrease the power to the one or more point heaters based on data of the parameters measured by the one or more sensors.

2. The processing chamber according to claim 1, wherein the one or more sensors include thermocouples.

3. The processing chamber according to claim 2, wherein the thermocouple is an internal thermocouple, and at least one of the one or more point heaters is disposed radially outside the internal thermocouple.

4. The processing chamber according to claim 3, wherein the one or more sensors further include one or more external thermocouples disposed radially outside the internal thermocouple.

5. The processing chamber according to claim 4, wherein the one or more external thermocouples include a front edge thermocouple and a trailing edge thermocouple.

6. The processing chamber according to claim 3, wherein the internal thermocouple is suspended on the substrate support.

7. The processing chamber according to claim 1, wherein the one or more sensors include pyrometers, the one or more point heaters are disposed radially outside the pyrometers, and the one or more sensors and the one or more point heaters are mounted on a reflector disposed outside a processing area of the internal volume.

8. The processing chamber according to claim 7, wherein the pyrometer is an internal pyrometer aligned with a central region of the substrate support, and the one or more sensors further include one or more external pyrometers radially disposed between the internal pyrometer and the one or more point heaters.

9. The processing chamber according to claim 1, wherein the one or more sensors and the one or more point heaters communicate via closed-loop or open-loop control.

10. The processing chamber according to claim 1, wherein the energy module includes a plurality of heat sources, and the controller is operable to control the plurality of heat sources independently or in grouped partitions based on the data of the parameters measured by the one or more sensors.

11. The processing chamber according to claim 1, wherein the controller is configured to predict an algorithm for activating the one or more point heaters.

12. The processing chamber according to claim 1, wherein the controller is operable to synchronize the operation of the one or more point heaters with one or more of: rotation of the substrate support, gas supply, or operation of the energy module.

13. A point heating module, comprising: a reflector; and One or more spot heaters mounted to the reflector, the one or more spot heaters being operable to emit energy into the internal volume, the one or more spot heaters including a retainer and one or more lenses.

14. The spot heating module according to claim 13, wherein the one or more spot heaters are connected to one or more electromagnetic radiation sources via one or more optical fibers.

15. The spot heating module according to claim 14, wherein the one or more optical fibers are connected between the one or more lenses and the one or more electromagnetic radiation sources.

16. The spot heating module according to claim 15, wherein an end of at least one of the one or more optical fibers is coupled to at least one of the one or more lenses.

17. The spot heating module according to claim 15, wherein the retainer holds at least one of the one or more optical fibers.

18. The spot heating module according to claim 15, wherein the retainer holds at least one of the one or more lenses, and the retainer is mounted to the reflector.

19. The spot heating module according to claim 16, wherein the retainer includes a cylinder having a central opening, and at least one of the one or more lenses is received in the central opening.

20. The spot heating module according to claim 13, wherein the energy has a wavelength in the range of about 200 nm to about 900 nm.

21. The spot heating module according to claim 20, wherein the wavelength is about 810 nm.

22. The spot heating module according to claim 13, wherein the energy includes radiation beams having different wavelengths.

23. The spot heating module according to claim 13, further comprising one or more thermal sensors, the one or more thermal sensors being operable to measure a parameter.

24. The spot heating module according to claim 23, wherein the one or more thermal sensors are mounted to the reflector.

25. The spot heating module according to claim 24, wherein the one or more thermal sensors are positioned to measure the parameter through one or more ports of the reflector.

26. A processing chamber, comprising: a chamber body that at least partially defines an internal volume; a substrate support disposed within the chamber body; an energy module facing the substrate support; and the spot heating module according to any one of claims 13-25, wherein the reflector is disposed outside a processing region of the internal volume.

27. The processing chamber according to claim 26, further comprising a controller operable to rotate the substrate support and power the one or more spot heaters to define an annular heating zone as the substrate support rotates.

28. The processing chamber according to claim 27, wherein the one or more point heaters are oriented to focus energy to a specific location during rotation of the substrate support, locally heating the specific location.

29. The processing chamber according to claim 28, wherein the specific location corresponds to one or more of the following: a location adjacent to the lift pins, or a marked location of a deposition thickness profile.

30. The processing chamber according to claim 26, further comprising a controller operable to rotate the substrate support and pulse the one or more point heaters to heat a discrete area while the substrate support is rotating.

31. The processing chamber according to claim 30, wherein the controller is operable to synchronize the pulses with the rotation of the substrate support, and the duration of the pulses determines the angular scan of the exposure along the annular heating zone.

32. A processing chamber comprising: a chamber body including an upper flat housing and a lower flat housing that at least partially define an internal volume; a substrate support disposed within the chamber body; an energy module disposed outside the housing and facing the substrate support; a cover disposed over the energy module; and one or more point heaters mounted to the cover and operable to emit energy into the internal volume.

33. The processing chamber according to claim 32, wherein the chamber body is in the shape of a rectangular box.

34. The processing chamber according to claim 32, wherein the upper flat housing and the lower flat housing are made of transparent quartz, the cover is a reflector including one or more ports, and the one or more point heaters are positioned to heat through the one or more ports of the reflector.

35. The processing chamber according to claim 34, wherein the energy module includes a plurality of elongated tubular heat sources spaced apart from each other and disposed above the upper flat housing.

36. The processing chamber according to claim 35, further comprising a plurality of second elongated tubular heat sources spaced apart from each other and disposed below the lower flat housing.

37. The processing chamber according to claim 35, wherein the plurality of elongated tubular heat sources are oriented parallel to a reaction gas flow path in the internal volume.

38. The processing chamber according to claim 35, wherein the plurality of second elongated tubular heat sources are oriented transverse to the plurality of elongated tubular heat sources.

39. The processing chamber according to claim 32, further comprising: one or more sensors operable to measure parameters in the internal volume; and a controller operable to increase or decrease the power to the one or more point heaters based on data of the parameters measured by the one or more sensors.

40. The processing chamber according to claim 32, wherein the substrate support includes a substrate retainer and support legs, the support legs being mounted to a shaft extending through a tube, the tube extending through the bottom of the chamber, wherein the tube is in communication with a purge gas source.

41. The processing chamber according to claim 32, further comprising a plurality of lower spot heaters oriented to heat a lower side of the substrate support.

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