Atomic layer etching and deposition processing systems including lens circuits with telecentric lenses, beam folding components, or polygon scanners

Abstract

A substrate processing system includes a processing chamber, a substrate support, a laser, and a collimation assembly. The substrate support is disposed in the processing chamber and configured to support a substrate. The laser is configured to generate a laser beam. The collimation assembly includes a plurality of lenses or mirrors arranged to direct the laser beam toward the substrate to heat exposed material of the substrate. The plurality of lenses or mirrors are configured to direct the laser beam in a direction within a predetermined range perpendicular to a surface of the substrate.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 767,574, filed on November 15, 2018, and U.S. Provisional Application No. 62 / 668,552, filed on May 8, 2018. The entire disclosures of the above-referenced applications are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to substrate etching and deposition processes, and more particularly to atomic layer etching and deposition. Background Art

[0004] The background description provided here is for the purpose of generally presenting the context of the present disclosure. No admission is made, either explicitly or implicitly, that the work of the presently designated inventors is prior art to the present disclosure to the extent that it is described in this background section and in aspects of the specification that were not determined to be prior art at the time the application was filed.

[0005] During atomic layer etching (ALE) of substrates such as semiconductor wafers, a reactant (e.g., chlorine (Cl2) gas) is introduced into the process chamber to modify the surface of the substrate. x Chlorine-based gases are often used in ALE processes to provide a top layer of chlorine implantation. For example, chlorine gas can be introduced to convert the top portion of the silicon substrate formed of Si into silicon chloride (SiCl x ) layer, wherein x is 1, 2, 3, or 4. After the surface modification, the chlorine gas is purged from the chamber. Argon (Ar) plasma is provided to perform ion bombardment and actively remove the silicon chloride reaction layer, and then by-products are purged. Summary of the Invention

[0006] A substrate processing system is provided, comprising: a processing chamber, a substrate support, a laser, and a collimation assembly. The substrate support is disposed in the processing chamber and configured to support a substrate. The laser is configured to generate a laser beam. The collimation assembly includes a plurality of lenses or mirrors arranged to direct the laser beam toward the substrate to heat exposed material of the substrate. The plurality of lenses or mirrors are configured to direct the laser beam in a direction within a predetermined range perpendicular to a surface of the substrate.

[0007] In other features, the substrate processing system further includes a lens circuit including beam shaping optics to convert the laser beam from a circular laser beam to a square laser beam.

[0008] In other features, the substrate processing system further includes a lens circuit comprising a flat top optic for converting the laser beam from a circular laser beam to a flat top shaped laser beam and a diffraction optic for converting the flat top shaped laser beam to a square laser beam.

[0009] In other features, the substrate processing system further includes a controller configured to perform a rapid thermal annealing process, the rapid thermal annealing process comprising: (i) generating a control signal to modulate the laser beam so as to subject the exposed material to a plurality of thermal energy pulses, and (ii) enabling the exposed material to cool between successive thermal energy pulses in the plurality of thermal energy pulses. In other features, the substrate processing system further includes a mirror circuit comprising a first mirror, a second mirror, a first motor, and a second motor. The controller is configured to move the first mirror and the second mirror via the first motor and the second motor to adjust the position of the laser beam on the substrate.

[0010] In other features, the substrate processing system further comprises a beam size adjustment device configured to adjust a size of the laser beam before the laser beam is received by the substrate.

[0011] In other features, the collimation assembly includes a telecentric lens assembly, the telecentric lens assembly including a lens arranged to direct the laser beam toward the substrate to heat the exposed material. The lens is configured to direct the laser beam in a direction perpendicular to the surface of the substrate. The lens is configured to direct the laser beam in a direction perpendicular to the surface of the substrate. In other features, the substrate processing system also includes a mirror circuit and a controller. The mirror circuit includes a first mirror, a second mirror, a first motor, and a second motor. The laser beam is directed toward the first mirror. The laser beam is directed from the first mirror to the second mirror. The laser beam is directed from the second mirror through the telecentric lens assembly and to the substrate. The controller is configured to move the first mirror and the second mirror via the first motor and the second motor to adjust the position of the laser beam on the substrate.

[0012] In other features, the plurality of lenses maintain the laser beam in a perpendicular relationship to the surface of the substrate as the controller adjusts the position of the laser beam on the substrate.

[0013] In other features, the process chamber is an inductively coupled plasma chamber or a remote plasma source connection chamber. The telecentric lens assembly is located above a dielectric window of the process chamber. In other features, the plurality of lenses are plano-convex lenses. In other features, the plurality of lenses have different diameters.

[0014] In other features, the lenses are arranged in series and include a first lens and a last lens. The diameter of the plurality of lenses increases from the first lens to the last lens. In other features, the laser beam is received at the first lens and output from the last lens to the substrate.

[0015] In other features, the collimation assembly includes a beam folding assembly including a reflector arranged to direct the laser beam toward the substrate to heat the exposed material. The plurality of lenses are configured to direct the laser beam in a direction perpendicular to the surface of the substrate. The reflector is arranged to reflect and direct the laser beam in a direction within a predetermined range of directions perpendicular to the surface of the substrate.

[0016] In other features, the substrate processing system further includes a controller configured to control the laser to pulse the laser beam at a predetermined frequency.

[0017] In other features, the substrate processing system further includes a gas delivery system and a controller. The gas delivery system is configured to supply process gas to the processing chamber. The controller is configured to control the gas delivery system and the laser to iteratively perform an isotropic atomic layer etching process. The process includes: performing pretreatment, atomic adsorption, and pulsed thermal annealing during the iterative process of the isotropic atomic layer etching process; during the atomic adsorption, exposing the surface of the substrate to the process gas including a halogen species, the halogen species being selectively adsorbed onto the exposed material of the substrate to form a modified material; and during the pulsed thermal annealing, turning on and off the laser pulses multiple times within a predetermined time to expose and remove the modified material.

[0018] In other features, the substrate processing system further includes: an acousto-optic modulator configured to receive the laser beam; and a controller configured to generate a radio frequency signal. The laser is configured to operate in a continuous mode. The acousto-optic modulator is configured to switch between allowing the laser beam to pass through the plurality of lenses or mirrors and preventing the laser beam from passing through the lenses or mirrors at a predetermined frequency based on the radio frequency signal.

[0019] In other features, the collimation assembly includes a beam folding assembly including a reflector. The reflector is arranged to direct the laser beam toward the substrate to heat the exposed material. The lens is configured to direct the laser beam in a direction perpendicular to the surface of the substrate. The reflector is arranged to reflect and direct the laser beam in a direction within a predetermined range of perpendicularity to the surface of the substrate.

[0020] In other features, the substrate processing system further comprises a gas delivery system configured to supply a process gas to the processing chamber. The controller is configured to control the gas delivery system and the laser to iteratively perform an isotropic atomic layer etching process. The process comprises: performing pretreatment, atomic adsorption, and pulsed thermal annealing during the iterative process of the isotropic atomic layer etching process; during the atomic adsorption, exposing the surface of the substrate to the process gas comprising a halogen species, the halogen species being selectively adsorbed onto the exposed material of the substrate to form a modified material; and during the pulsed thermal annealing, generating the radio frequency signal to modulate the laser beam within a predetermined time period to expose and remove the modified material.

[0021] Among other features, a substrate processing system is provided that includes: a processing chamber, a substrate support, a laser, a lens circuit, and at least one of a reflector or a polygon scanner. The substrate support is disposed in the processing chamber and configured to support a substrate. The laser is configured to generate a circular laser beam. The lens circuit is configured to convert the circular laser beam into a linear beam. At least one of the reflector or the polygon scanner is arranged to direct the linear beam toward the substrate to heat exposed material of the substrate.

[0022] In other features, the at least one of the mirror or the polygon scanner is configured to direct the line beam along a direction within a predetermined range of normal to the surface of the substrate.

[0023] In other features, the lens circuit includes: a flat top optic configured to convert the circular laser beam into a flat top shaped laser beam; and a beam shaping optic configured to convert the flat top shaped laser beam into the linear beam.

[0024] In other features, the polygon scanner includes a plurality of sides. Each of the plurality of sides is implemented as a reflector or includes a reflector. In other features, the substrate processing system further includes: a motor connected to the polygon scanner and configured to rotate the polygon scanner; and a controller configured to control operation of the motor to rotate the polygon scanner so that the linear beam moves across the surface of the substrate.

[0025] In other features, the substrate processing system further includes: a motor connected to the mirror and configured to rotate the mirror; and a controller configured to control operation of the motor to rotate the mirror so that the linear beam moves across the surface of the substrate.

[0026] In other features, the substrate processing system further includes: a gas delivery system configured to supply process gas to the process chamber; and a controller configured to control the gas delivery system and the laser to iteratively perform an isotropic atomic layer etching process. The process includes: performing pretreatment, atomic adsorption, and pulsed thermal annealing during the iterative process of the isotropic atomic layer etching process; during the atomic adsorption, exposing the surface of the substrate to the process gas including a halogen species, the halogen species being selectively adsorbed onto the exposed material of the substrate to form a modified material; and during the pulsed thermal annealing, turning on and off the laser pulses multiple times within a predetermined time to expose and remove the modified material.

[0027] In other features, the substrate processing system further includes: an acousto-optic modulator configured to receive the laser beam; and a controller configured to generate a radio frequency signal. The laser is configured to operate in a continuous mode. The acousto-optic modulator is configured to switch between allowing the laser beam to pass to the polygon scanner and preventing the laser beam from passing to the polygon scanner at a predetermined frequency based on the radio frequency signal. In other features, the substrate processing system further includes a gas delivery system configured to supply a process gas to the processing chamber. The controller is configured to control the gas delivery system and the laser to iteratively perform an isotropic atomic layer etching process. The process includes: performing pretreatment, atomic adsorption and pulsed thermal annealing during the iterative process of the isotropic atomic layer etching process; exposing the surface of the substrate to the process gas including a halogen substance during the atomic adsorption, and the halogen substance is selectively adsorbed onto the exposed material of the substrate to form a modified material; and generating the radio frequency signal to modulate the laser beam within a predetermined time period during the pulsed thermal annealing process to expose and remove the modified material.

[0028] Further scope of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0030] Figure 1 is a functional block diagram of an example of a substrate processing system including a flash lamp and a rapid thermal pulse controller for performing rapid thermal pulse operations during ALE and atomic layer deposition (ALD) according to the present disclosure;

[0031] Figure 2 is a functional block diagram of an example of a substrate processing system including a laser, a lens circuit, and a rapid thermal pulse controller for performing rapid thermal pulse operations during ALE and ALD according to the present disclosure;

[0032] Figure 3 is combined with Figure 2 A side cross-sectional view of a reflector and telecentric lens assembly in a lens circuit;

[0033] Figure 4 is a temperature profile over time illustrating exemplary heating ramp and cooling time periods associated with a conventional continuous wave mode of operation;

[0034] Figure 5 is an example temperature profile over time illustrating an exemplary rapid heat pulse according to the present disclosure;

[0035] Figure 6 is an ALE process diagram according to the present disclosure;

[0036] Figure 7 is an exemplary signal graph illustrating temperature versus time for a single rapid heat pulse provided in accordance with the present disclosure;

[0037] Figure 8 is a graph of exemplary etch rate versus laser energy density for ALE performed according to the present disclosure;

[0038] Figure 9 is an exemplary graph of germanium removal versus process cycle number for ALE performed according to the present disclosure;

[0039] Figure 10 is an example graph of film thickness showing different amounts of material removal for: a control, pulsed laser heating without chlorine adsorption, chlorine adsorption without pulsed laser heating, and a combination of implementations of chlorine adsorption and pulsed laser heating;

[0040] Figure 11 is an example graph of estimated temperature ranges and lamp power ranges for some processes;

[0041] Figure 12 is an example graph illustrating a rate of change of surface temperature during a flash lamp cycle performed in accordance with the present disclosure and an example graph illustrating a rate of change of surface temperature during a corresponding cool-down period following the flash lamp cycle;

[0042] Figure 13 is an example graph of flash lamp (lap) power level and repetition rate versus pulse duration of a flash lamp cycle in accordance with the present disclosure;

[0043] Figure 14 is a diagram illustrating iterative execution of rapid heat pulse cycles for removing portions of a dielectric layer according to the present disclosure;

[0044] Figure 15 An ALE method according to the present disclosure is shown;

[0045] Figure 16 is an exemplary graph of etch rate versus substrate surface temperature during an ALE process according to the present disclosure;

[0046] Figure 17 is a graph showing exemplary cooling rate versus heating rate for different heat sources;

[0047] Figure 18 is a block diagram illustrating two exemplary ALE methods for removing a titanium nitride layer according to the present disclosure;

[0048] Figure 19 This is an example diagram of titanium nitride film thickness for different energy levels.

[0049] Figure 20 is an exemplary graph of titanium nitride film thickness versus different numbers of ALE cycles performed according to the present disclosure;

[0050] Figure 21 is an example graph of titanium nitride film thickness showing different amounts of material removal for different operations performed;

[0051] Figure 22 is a functional block diagram of an example of a substrate processing system incorporating an acousto-optic modulator according to an embodiment of the present disclosure;

[0052] Figure 23 is a side view showing a mirror and substrate showing an angle of incidence according to an embodiment of the present disclosure;

[0053] Figure 24is a functional block diagram of an example of a substrate processing system incorporating a beam folding assembly according to an embodiment of the present disclosure;

[0054] Figure 25 is a functional block diagram of an example of a substrate processing system including circular beam to linear beam shaping optics and at least one of a mirror or a polygon scanner according to an embodiment of the present disclosure.

[0055] Figure 26 is a cross-sectional view of a circular beam and a linear beam according to an embodiment of the present disclosure; and

[0056] Figure 27 is a graph of linear beam size deviation versus distance between a reflector and a substrate surface according to an embodiment of the present disclosure.

[0057] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0058] In order to manufacture devices below 7 nanometers, it is necessary to isotropically remove material from the substrate with nanoscale control. At the nanoscale, traditional dry etching and wet etching can cause roughness and / or damage to the substrate surface. In addition, ALE is limited in isotropic removal due to ion directionality. In order to remove, for example, the upper portion of the substrate, the upper portion can be modified to provide an upper volatile layer. The upper volatile layer can then be removed by heating the upper volatile layer via a lamp. A conventional lamp (e.g., an infrared lamp) can heat a portion of the substrate at a rate of 40-250°C / second, for example. The time it takes for the lamp to heat the upper volatile layer and cool the upper volatile layer may take several minutes. The amount of time required to heat and cool the substrate can be based on the heating and cooling rates of a substrate support such as an electrostatic chuck. The time it takes for the substrate and substrate support to heat and cool may take tens of minutes.

[0059] Because the substrate heating time is long, the entire substrate, including the base or bulk, is typically heated. Consequently, conventional heating methods using extended heating lamps present thermal budget issues due to heating the bulk of the substrate, rather than just the upper portion and / or surface. This heating method is limited to certain etching processes. The thermal budget refers to the time a substrate can be exposed to a specific temperature without: degrading the substrate's material and / or composition; negatively impacting the performance and / or operation of die components on the substrate; and / or causing interdiffusion issues, where molecules and / or atoms from one material layer diffuse into another. The higher the temperature and the longer the exposure time, the more likely and prevalent thermal budget issues will occur. For example, using conventional heating lamps, a thermal cycle with a temperature increase exceeding 200°C can cause Si to diffuse into Ge, while a thermal cycle with a temperature increase of 40°C may not. Thermal budget issues limit the processes that can be performed on a substrate, especially within a single processing chamber. To avoid waiting for the substrate support to cool and to quickly perform different processes, it may be necessary to move the substrate between processing chambers.

[0060] The example set forth herein includes a rapid thermal pulse (RTP) system, which is used to perform an RTP cycle by a heat source to quickly increase the temperature of the upper portion of the substrate. By quickly heating the upper portion of the substrate without heating the base portion or the main body portion, the upper portion of the substrate can quickly reduce the temperature after deactivating the heat source. As described below, multiple heating and cooling cycles can be performed in a few seconds. RTP is provided, and thermal budget problems are prevented. In other words, thermal heating is provided without heating and / or minimizing the amount of heating of the lower main body portion of the substrate. This enables the surface and / or upper portion of the substrate to be rapidly heated and cooled to quickly perform multiple cycles and / or multiple different processes of a process in a single processing chamber. For example, the upper portion can be several hundred nanometers thick (or the depth heated to the substrate is several hundred nanometers) and measured from the heated surface of the substrate.

[0061] RTP operations also allow for processes not previously possible due to their sensitivity to thermal budget issues. For example, they can be used to isotropically and selectively remove certain film materials from substrates. These materials include silicon, germanium, metal oxides such as aluminum oxide, titanium oxide, and zirconium oxide, and other materials such as titanium nitride.

[0062] Now refer to Figure 1, shows an example of a substrate processing system 100 that can be used. Although the substrate processing system 100 includes an inductively coupled plasma (ICP) source, other types of processing chambers and / or plasma sources (e.g., remote plasma sources) can be used. A remote plasma source can optionally be provided to utilize free radicals. Another example of a processing chamber is a remote plasma source connection chamber (or first chamber) that is connected to another processing chamber (or second chamber). The substrate processing system 100 includes an RTP system 106 and a processing chamber 108. The processing chamber 108 includes a substrate support 110 for supporting a substrate 112. The RTP system 106 rapidly and iteratively heats a surface and / or a portion of the substrate 112. In some examples, the substrate support 110 includes an electrostatic chuck or a vacuum chuck. In some examples, the substrate support 110 is temperature controlled. For example, the substrate support 110 can include fluid channels 114 and / or heaters 116 that can be arranged in one or more regions. The substrate support 110 can further include an electrode 118.

[0063] One or more sensors 119, such as temperature and / or pressure sensors, may be disposed in the process chamber 108 to sense temperature and / or pressure, respectively. A valve 122 and a pump 124 may be used to control the pressure within the process chamber 108 and / or to exhaust reactants from the process chamber 108.

[0064] The RTP system 106 includes a heat source 126 that performs a rapid thermal anneal on the substrate 112. This includes RTP via a flash lamp 128. Figure 2 Another example of a laser-based RTP system is shown. A window assembly 130 may be positioned between the heat source 126 and the process chamber 108. Window assembly 130 includes a first (or dielectric) window 132, a reflector 134, a coupling member 136, and a second window 138. First window 132 may be a quartz window. Reflector 134 may be formed of stainless steel and may be conical in shape to direct heat energy generated by the flash lamp 128 toward the substrate 112. Second window 138 may be a sapphire window. Coupling member 136 connects reflector 134 to the process chamber 108. In one embodiment, reflector 134 is not included, and first window 132 is attached to coupling member 136. Flash lamp 128 may be cylindrical and include a corresponding cooling jacket 140 through which water and / or other cooling fluid may be circulated to cool flash lamp 128. Reflector 142 having a parabolic reflective portion 144 may be positioned above first window 132. Reflector 142 may be formed of aluminum. The flash lamps 128 are respectively disposed in the parabolic reflecting portion 144 between the reflector 142 and the first window 132 .

[0065] A temperature control system 150 may be used to control the temperature of the substrate support 110 and the substrate 112. The temperature control system 150 may control the supply of fluid from a fluid source 152 via a pump 154 ​​connected to the fluid channel 114. The temperature control system 150 may also control the operation of the heater 116. The temperature control system 150 may include one or more temperature sensors 156 to sense the temperature of one or more locations or regions of the substrate support 110.

[0066] The gas delivery system 160 includes one or more gas sources 164, one or more valves 106, one or more mass flow controllers 168, and a mixing manifold 170. The gas delivery system 160 selectively provides a plasma gas mixture, a carrier gas and / or an inert gas, and / or a purge gas mixture to the processing chamber 108 during pretreatment, doping, passivation, annealing, and / or purging.

[0067] RF generator 120-1 includes an RF source 123 and a matching network 125 that outputs RF power to a coil 127 surrounding the outer wall of the process chamber 108. RF generator 120-1 generates a magnetic field in the process chamber 108, thereby stimulating a plasma. Another RF generator 120-2 can be used to provide an RF bias to an electrode 118 in the substrate support 110. Controller 180 communicates with one or more sensors 119, valves 122 and pumps 124, a temperature control system 150, a heat source 126, RF generators 120-1 and / or 120-2, and a gas delivery system 160 to control the process being performed.

[0068] The controller 180 may include an RTP controller 182 that controls a capacitive discharge circuit 184 to pulse the flash lamp 128. The capacitive discharge circuit 184 may receive power from a power supply 186 and a control signal from the RTP controller 182. The capacitive discharge circuit 184 may charge a capacitor (represented by block 187) in an idle mode and may discharge the capacitor upon receiving a discharge signal from the RTP controller 182. The RTP controller 182 may perform RTP operations during an ALE and / or ALD process.

[0069] Figure 2 2 shows an example of a substrate processing system 200 that includes an RTP system 202 including a laser 204, a lens circuit 206, and a controller 208 having an RTP controller 210. The substrate processing system 200 may be similar to Figure 1 The substrate processing system 100 operates and includes the substrate processing system 100 Figure 21 . The substrate processing system 200 includes a laser 204, a lens circuit 206, and a controller 208 instead of the heat source 126, the controller 180, and the capacitor discharge circuit 184. The laser 204 is a heat source that can be pulsed (or modulated) by the RTP controller 210 during RTP operation according to control signals received from the RTP controller 210. This can occur during both ALE and ALD processes.

[0070] Lens circuit 206 includes beam shaping optics 212, a Galvano mirror circuit 213 including a first mirror 214 and a second mirror 216, and a telecentric lens assembly 218. Beam shaping optics 212 may include a flat-top (or first beam shaping) optic 220 and a diffraction (or second beam shaping) optic 222. Flat-top optic 220 is used to convert the laser beam received from laser 204 into a flat beam (e.g., a 2 centimeter (cm) x 2 cm flat-top beam), wherein the laser beam has a Gaussian distribution. The temperature profile of the laser beam is also Gaussian. An example of a flat-top optic is a "flywheel" optic.

[0071] The diffractive optical device 222 converts the flat top circular beam from the flat top optical device 220 into a square beam. The square beam has a corresponding uniform temperature distribution on the substrate. This enables a uniform thermal reaction and / or etching rate on the portion of the substrate (e.g., substrate 112) exposed to the square beam. Providing a square beam also provides a beam with a shape that matches the shape of the heated die. The square beam can uniformly heat the surface or upper portion of the selected die. The substrate 112 can be disposed on a substrate support in the processing chamber 108.

[0072] The beam size adjustment device 226 can be disposed between the beam shaping optics 212 and the first reflector 214. The beam size adjustment device 226 can adjust the size of the square beam to be greater than or equal to the size of the die. The beam size adjustment device 226 can be motorized and can include a beam expander 227. The beam expander 227 can perform amplification and increase the size of the laser beam.

[0073] The RTP controller 210 and the current mirror circuit 113 can function as an XY galvanometer scanning system. A first mirror 214 can be used to move the laser beam across the surface of the substrate 112 in a first (or X) direction. A second mirror 216 can be used to move the laser beam across the surface of the substrate in a second (or Y) direction. The controller 208 and / or the RTP controller 210 can move the mirrors 214, 216 via motors 230, 232.

[0074] The telecentric lens assembly 218 can be referred to as a collimating assembly and includes a series of plano-convex lenses 240, 242, 244, 246. Although a specific number of plano-convex lenses is shown, a different number of plano-convex lenses can be included. The plano-convex lenses 240, 242, 244, 246 have larger diameters as they are closer to the window assembly 130, such that: the diameter of lens 242 is greater than the diameter of lens 240; the diameter of lens 244 is greater than the diameter of lens 242; and the diameter of lens 246 is greater than the diameter of lens 244. The plano-convex lenses 240, 242, 244, 246 are vertically aligned to have a common centerline 248. The plano-convex lenses 240, 242, 244, 246 are held in a fixed relationship within a mold 250. The plano-convex lenses 240, 242, 244, 246 direct the laser beam received from the second reflector 216 normal to the surface of the substrate 112. The telecentric lens assembly 218 maintains the laser beam in an orthogonal relationship to the surface of the substrate 112 as the laser beam moves across the surface of the substrate 112 .

[0075] For example, the laser beam generated by laser 204 may have a diameter of 355 nm and may be pulsed every 80 picoseconds (ps).RTP controller 210 may move mirrors 214, 216 to perform a 150 Hertz (Hz) scan across the surface of substrate 112.

[0076] The substrate processing system 200 may include a temperature control system 150 that may be used to control the temperature of the substrate support 110 and substrate 112. The temperature control system 150 may include one or more temperature sensors 156 to sense the temperature of one or more locations or regions of the substrate support 110.

[0077] Figure 3 Shown Figure 2 216 and telecentric lens assembly 218. The mirrors 214 and 216 are shown and direct the laser beam 300 through the telecentric lens assembly 218. The laser beam 300 passes through the lenses 240, 242, 244, 246 from the smallest lens 240 to the largest lens 246. When the laser beam 300 is circular and does not pass through Figure 2 When the beam shaping optics 212 are provided, the laser beam has a Gaussian distribution as represented by curve 302 at the image plane 304 or surface of the substrate 112. When the laser beam 300 passes through the beam shaping optics 212, the laser beam has a square shape and a spot with side S.

[0078] Figure 2The current mirror circuit 213 provides a system including two mirrors for scanning the full field of view (FOV). For example, the FOV can be greater than 300 mm × 300 mm. In one embodiment, the lenses 240, 242, 244, 246 generally have a low numerical aperture (less than a predetermined numerical aperture) and a focal length parameter (or beam perpendicularity parameter) within a predetermined range perpendicular to the image plane 304. While maintaining beam uniformity and intensity, a laser beam is provided perpendicular to the image plane without beam distortion at the image plane. The laser beam can be focused on the image plane 304. In one embodiment, the pupil aperture or size of the side S of the beam spot is limited to 10-12 mm. Figure 2 The beam size adjustment device 226 can increase the size of the beam spot so that S is 20-22 mm.

[0079] The flange focal length (FFL) and back focal length (BFL) are shown. The FFL can be the distance between (i) the end of the flange 305 and / or the point 307 where the lens 246 begins to curve and protrude outward toward the image plane 304, and (ii) the image plane 304. The BFL can refer to the distance between (i) the point 309 on the lens 246 closest to the image plane 304, and (ii) the image plane 304.

[0080] Figures 1 to 3 The above examples provide a flash lamp example and a laser beam example. The flash lamp can be modulated (or pulsed) every predetermined number of microseconds (e.g., every 300 μs), and the laser beam can be modulated (or pulsed) every predetermined number of picoseconds (e.g., every 80 ps). These examples enable sequential thermal ALE or ALD processes to be performed. For example, a 100 μs pulsed light source can be used that provides a pulse per square centimeter (cm2) at a period of 1 Hz. 2 ) 8 joules (J) of lamp power. For a single recipe within a single process chamber, greater than 50 cycles can be performed. ALE processes, including atomic and isotropic removal of materials, can be performed. These processes are performed efficiently while controlling substrate temperature without thermal budget issues.

[0081] Figure 4 A temperature curve over time is shown, illustrating exemplary heating ramp-up and cooling periods associated with a conventional continuous wave mode of operation. As shown, a conventional heating lamp operating in continuous wave mode can heat a substrate from 20°C to 100-600°C in x seconds. The heating lamp is on for t minutes. The substrate cools in y seconds.

[0082] Figure 5 An exemplary temperature profile over time is shown, illustrating an exemplary rapid heat pulse. Figure 5, low temperature pulses and high temperature pulses are shown for illustrative purposes. For example, a low temperature pulse may be provided so as to raise the temperature of a portion of the substrate to 80°C per cycle. A high temperature pulse may raise the temperature of a portion of the substrate to 600°C per cycle. In one embodiment, the low temperature pulse raises the temperature of a portion of the substrate to 20-80°C. In one embodiment, the high temperature pulse raises the temperature of a portion of the substrate to 100-600°C. In another embodiment, no low temperature pulse is provided. Between each pair of consecutive low temperature pulses and / or high temperature pulses, the heated portion of the substrate is cooled to, for example, a baseline temperature (e.g., 20°C). A plurality of low temperature and / or high temperature pulses may be provided, and the heated portion of the substrate may be cooled between consecutive pulses in a pulse within a predetermined number of seconds (shown as X seconds). For example, a plurality of low temperature pulses and high temperature pulses may be provided over a period of 3-10 seconds.

[0083] The RTP described herein enables heating and controlling the temperature of the substrate surface. Heating is provided to a predetermined depth of the substrate in a controllable and adjustable manner while providing control of the atomic reaction. This can be achieved by controlling the number, length, intensity, and frequency of the light (e.g., flash lamp or laser) pulses generated. In one embodiment, a series of high temperature pulses is provided. In other embodiments, a series of low temperature pulses is provided. In another embodiment, a combination of low temperature and high temperature pulses is provided, and the duration, intensity (or power level), and frequency of the pulses are controlled to provide a temperature depth profile across at least a portion of the surface of the substrate. By having a Figure 1 In an embodiment of the present invention, different temperature zones can be created by operating the flash lamps differently. For example, one or more flash lamps of a first group of flash lamps can be operated to provide a first series of pulses having a first set of one or more durations, one or more intensity levels (or power levels), and one or more frequencies, and one or more flash lamps of a second group of flash lamps can be operated to provide a second series of pulses having a second set of one or more durations, one or more intensity levels (or power levels), and one or more frequencies.

[0084] Figure 6 An ALE process diagram illustrating a thermal ALE process performed in accordance with the present disclosure is shown. The thermal ALE process may include iterative execution of pre-treatment, atomic adsorption (or condensation), RTP (or thermal removal), and surface refresh (or sweep) operations. Compared to conventional continuous wave (CW) heating methods, RTP can be used to atomically and isotropically remove films without thermal budget issues. In one embodiment, the thermal pulse duration is less than 3 ms and the surface substrate temperature is raised to approximately 500°C to avoid thermal budget issues. For example, such RTP may be performed when etching silicon (Si) to prevent Si from diffusing into germanium (Ge).

[0085] During the pretreatment (or first surface modification operation), hydrogen H2, ammonia NH3 and / or other gases may be provided while providing plasma to modify the surface and / or portion of the substrate. During the atomic adsorption (or second surface modification operation), oxygen, halogen gas (e.g., chlorine Cl2, iodine I2, fluorine F3 or other halogen gas), nitrogen trifluoride NF3 and / or other reactants may be provided and adsorbed onto the surface and / or portion of the substrate. The portion of the substrate subjected to atomic adsorption may be composed of, for example, a metal oxide MO. x , such as aluminum (Al) oxide Al2O3, titanium (Ti) oxide TiO2 or zirconium (Zr) oxide, or other materials such as silicon nitride SiN x , Si, Ge, SiO2, titanium nitride TiN or hafnium oxide HfO2. After atomic adsorption, the removed parts can be, for example: oxides or halides with or without ligands; MCl x (F x ); aluminum fluoride AlF3; titanium oxide TiO2; ammonium fluorosilicate (NH4)2SiF6; or other modified materials.

[0086] In one embodiment, a predetermined number of cycles are performed to remove a predetermined amount of one or more layers of the substrate. For example, the top 1 nm thick layer of the substrate may be removed in each cycle of the thermal ALE process. During rapid thermal operation, such as Figure 1-2 As shown, a flash lamp assembly or a laser can be used. Table 1 provides five examples (one per row) of thermal ALE processes performed on different types of substrates. The columns represent: a) the substrate material being removed; b) the type of plasma provided during pre-treatment (PT); c) the gas provided during the atomic adsorption (AA) operation; d) the rapid thermal (RT) heating operation, which can use a flash lamp or a laser; and the sweep gas provided during the surface refresh (SR) operation.

[0087]

[0088] Table 1

[0089] The thermal ALE process disclosed herein can be performed on other types of substrates. The thermal ALE process can be performed to remove a target film comprising, for example, germanium Ge, a metal nitride (e.g., TiN), a compound comprising Si-SiGe, and / or a metal oxide (e.g., Al2O3 or HfO2). The corresponding byproducts that can be removed include germanium oxide GeO, titanium oxychloride TiOCl, titanium oxyfluoride TiOF, chlorosilicon Si-Cl, fluorosilicon Si-F, chlorogermanium Ge-Cl, fluorogermanium Ge-F, aluminum acetylacetonate Al(acac)4, and hafnium acetylacetonate Hf(acac)4.

[0090] During the surface refresh operation, the substrate can be cooled. In one embodiment, active cooling is provided to cryogenically cool the substrate. This reduces the time to cool the substrate and allows more cycles to be performed in a shorter period of time. Active cooling provides rapid recovery without negatively impacting the base (or bulk) portion of the substrate.

[0091] Figure 7 An exemplary signal diagram is shown that illustrates a temperature variation pattern over time for a single rapid heat pulse 700 provided. During an ALE or ALD process, a pulsed heat source can be used to control surface reactions of a substrate within a predetermined number of milliseconds. In one implementation, a plasma can be generated by turning on source power (represented by pulse 701 of curve 702) and supplying a gas (represented by pulse 703 of curve 704) to a processing chamber. The plasma can be generated by turning on a pump (e.g., Figure 1 The process chamber may then be purged, as represented by pulse 710 of curve 712 and pulse 713 of curve 708. Optionally, bias power may be provided, as represented by pulse 714 of curve 716. The pump may then be enabled to perform a sweep, as represented by pulse 718.

[0092] Figure 8 An exemplary etch rate versus laser energy density graph for ALE performed is shown, illustrating the differences for Ge without H2 plasma surface modification, Ge with H2 plasma surface modification, p-type Si with H2 plasma surface modification, and p-type Si without H2 plasma surface modification.

[0093] Due to the similarity of byproducts formed by etching silicon and germanium layers during plasma treatment, selectively removing a portion of a silicon layer or a germanium layer of a substrate having both silicon and germanium layers can be challenging for nanowire fabrication processes. The exemplary embodiments disclosed herein enable selective removal of Si or Ge layers of a substrate having both Si and Ge layers. Exemplary implementations include RTP to heat the surface temperature of the substrate within a certain process time window. An H2 plasma treatment for surface modification is performed, and the reaction time is controlled to selectively etch the Si layer or the Ge layer. The process avoids thermal budget issues, unlike conventional heated substrate supports that may encounter thermal budget issues of interdiffusion.

[0094] The following Figure 9-10Figure 2 shows the difference between using O₂ and Cl₂ for atomic adsorption during thermal ALE of Ge and TiN. The removal rates for Ge and TiN increase linearly with increasing process cycles. The selectivity is controlled by the pretreatment chemistry and the thermal energy provided. Figure 9 The amount of Ge removed is plotted against the number of process cycles for ALE performed. Germanium is removed at ambient (or room temperature) temperature. Figure 10 Film thickness is shown, showing different amounts of material removal for the following cases: a control, laser RTP (laser pulse heating) without pretreatment and chlorine adsorption; pretreatment and chlorine adsorption without laser RTP; and a combination of pretreatment, chlorine adsorption, and laser RTP. The control implementation refers to the case where neither laser pulse heating nor chlorine adsorption was performed. Film thickness ranges 1002, 1004, 1006, 1008 are shown, providing exemplary ranges of thickness for the following cases: the control, laser heating without pretreatment and chlorine adsorption, pretreatment and chlorine adsorption without laser RTP, and a combination of pretreatment, chlorine adsorption, and laser RTP implementations. Chlorine adsorption with laser RTP removed material at a rate 10 times faster than without chlorine adsorption and laser RTP.

[0095] Figure 11 Estimated temperature ranges and lamp power ranges for certain processes are shown. These processes include: an ALE process for removing Si or SiO2, as represented by range 1102; a Ge removal process, as represented by 1104; and an annealing process, including RTP, as represented by 1106. The Ge removal is shown to be performed at a temperature of approximately 500°C with a lamp power per unit area of ​​27 J / cm 2 .

[0096] Figure 121 is a corresponding example graph illustrating the rate of change of surface temperature during a flash lamp cycle performed in accordance with the present disclosure, and the rate of change of surface temperature during a corresponding cool-down period following the flash lamp cycle. When heated to a surface temperature of 600° C., a rapid heat pulse duration of less than 0.3 ms can be provided. Curves 1202, 1204, 1206, 1208, 1210, 1212, and 1214 illustrate the temperature change at depths of less than 1 μm, 5 μm, 50 μm, 100 μm, 200 μm, 400 μm, and 800 μm, respectively. Curves 1202, 1204, 1206, 1208, 1210, 1212, and 1214 are shown for a 4 ms period. Curve 1220 is shown to illustrate the amount of time it takes for the surface of the substrate to cool to ambient (or room temperature) without active cooling after the 4 ms period. As shown, the cool-down time can be 0.5 seconds. As shown in the curve, multiple cycles can be performed without increasing the temperature of the base (or bulk) portion of the substrate. Shorter pulse times and / or active cooling can further reduce recovery time and further prevent thermal budget issues from occurring.

[0097] Figure 13 A graph showing the relationship between flash lamp power level and repetition rate and pulse duration for a flash lamp cycle is shown. Flash lamp power level and repetition rate are provided for certain fast thermal pulse durations. Repetition rate refers to the number of pulses per second (e.g., 2 pulses per second is 2 Hz). The maximum flash lamp power can be 80 J / cm 2 , the maximum pulse duration can be 6000 μs. For example, the rapid thermal process can include less than 30 J / cm 2 , with a duration of less than 3ms. As another example, 20J / cm 2 , to increase the surface temperature of the substrate by 400-500°C.

[0098] Figure 14 A diagram illustrating an iteratively performed rapid thermal pulse cycle to remove a portion of a dielectric layer from a portion of a substrate is shown. A layer stack 1400 is shown, from which a portion of a dielectric layer 1404 is removed during each cycle. The layer stack 1400 is disposed between two trenches (indicated by arrows 1405), which provide etching access to the sides of the dielectric layer 1404. The substrate may be pre-etched or cut to provide the trenches. The layer stack 1400 includes a mask layer 1402, a dielectric layer 1404 (e.g., a layer formed of Si), and a conductive layer 1406 (e.g., a conductive element or wire formed of SiGe). A portion of the dielectric 1404 is removed during each cycle of the corresponding RTP process. For example, portion 1408 is removed during the first cycle. Portion 1408 may be a single layer of the dielectric layer 1404.

[0099] Conventionally, the removal of portions of the Si or Ge layer is accomplished by (i) an anisotropic plasma etching process or (ii) an isotropic digital etching process comprising an oxidation (or wet) operation and a removal (or wet or dry) operation. Anisotropic plasma etching processes can cause layer damage, and isotropic digital etching processes (or wet processes) can cause layer pattern collapse, for example, in the center region of a multilayer due to tension caused by, for example, the use of wet chemicals. Dry etching can be performed instead of wet etching, but dry etching has a corresponding risk of layer damage. These problems are very common in nanoscale (or nanowire) applications. For example, a stack of Si nanowires extending over a predetermined distance can be 60 nm thick and spaced 20 nm apart. When wet etching is performed, the center region between the ends of the Si nanowires may collapse, reducing the gap between the Si nanowires to the extent that the Si nanowires touch each other.

[0100] The disclosed examples provide isotropic ALE with RTP to remove portions of a layer without layer damage and / or pattern collapse. In one embodiment, multiple cycles of oxidizing and removing portions of, for example, a Si layer using RTP are performed to provide a gate-all-around (GAA) field-effect transistor (FET) formed from the original layer stack. The process is a dry process that enables lossless high aspect ratio (HAR) atomic etch rate control.

[0101] The system disclosed herein can be operated using a variety of methods, Figure 15 An exemplary method is shown in . Figure 15 An ALE method for implementing RTP as described herein is shown. Although primarily concerned with Figure 1 and Figure 2 The following operations are described for implementation of the present disclosure, but these operations can be easily modified to apply to other embodiments of the present disclosure. These operations can be performed iteratively.

[0102] The method may begin at 1500. At 1502, a substrate (e.g., Figure 1 and 2 The substrate 112 having a diameter of 100 mm and / or a substrate having a diameter of 300 mm is placed in the processing chamber. At 1504, chamber operating parameters such as substrate support temperature, chamber pressure, RF power and bias power levels, and gas flow rates are set.

[0103] At 1506, the surface of the substrate is cleaned. For example, the substrate may include a Ge layer disposed on a Si layer. The upper surface of the Ge layer may be cleaned.

[0104] At 1508, a pretreatment can be performed, including exposing the substrate surface to, for example, H2 plasma or NH3 plasma for dechlorination and surface activation. For example, a plasma gas mixture containing hydrogen (H2) or ammonia (NH3) is supplied to the process chamber. In one embodiment, the surface modification is performed without a plasma, but rather using a gas with preselected chemical properties.

[0105] At 1510, atomic adsorption is performed. This can occur at low temperatures (e.g., less than or equal to 20° C.) and includes exposing the surface of the substrate to O 2 , Cl 2 , I 2 , NF 3 , or other reactants. In one embodiment, atomic adsorption is performed at a temperature below room temperature (or ambient temperature). For example, a non-plasma flow of Cl 2 can be provided. At 1512, the gas in the corresponding processing chamber is purged.

[0106] At 1514, a pulsed rapid thermal anneal is performed using, for example, a flash lamp, a laser, or other suitable lamp capable of rapid pulses as described herein (e.g., an infrared lamp). At least operations 1508-1515 may be performed iteratively, including adjusting the surface (or upper portion) temperature of the substrate. The surface (or upper portion) temperature may be modulated multiple times per second. For desorption / removal, a pulsed rapid thermal anneal is performed at 1514. This may include generating one or more pulses of thermal energy to heat the modified portion of the substrate. The temperature may be increased to evaporate certain molecules.

[0107] In operation 1514, the base and / or bulk of the substrate is maintained below a predetermined temperature (e.g., less than or equal to 20°C). GeCl2 begins to sublime above 260°C. SiCl2 begins to sublime above 650°C. In applications where a Ge layer is placed on a silicon layer, by applying appropriate laser pulse energy or flash lamp pulse energy, Ge can be selectively etched with infinite selectivity without etching Si. RTP enables a single process chamber configuration to be used with high throughput. Multiple processing operations can be performed in a single process chamber. Figure 16 Graphs showing the etch rates of Ge and Si versus substrate surface temperature during an ALE process performed as described above are shown. As another example, the pulse length may be 0.1 ms and may heat the surface and / or a portion of the substrate to 1000°C.

[0108] In some examples, each flash lamp pulse provides 10 J / cm 2 (i.e., energy per unit area of ​​the substrate) to 80 J / cm 2 In some examples, each laser pulse provides 10 mJ / cm 2 Up to 80mJ / cm 2In some examples, the annealing is performed for a predetermined time period in the range of 0.1 ms to 20 ms. In one embodiment, a flash lamp with a pulse duration of 1 ms or a laser with a pulse duration of 1 ps is used to heat the surface or upper portion of the substrate from an initial temperature to greater than 500° C. and then cool down to the initial temperature in less than 1 second.

[0109] Operations 1508, 1510, 1514 enable the control of atoms by atomically removing the upper layer of the substrate modified in operations 1508 and 1510. The rapid heating performed at 1514 provides an isotropic reaction without the use of plasma. In addition, the claimed heating enables rapid cooling, which also prevents thermal budget problems. Figure 17 Exemplary cooling rate versus heating rate relationships are shown for different heating sources and corresponding methods. Figure 17 The disclosed flash lamp and laser heating methods are shown to provide faster heating and cooling rates compared to other furnaces, IR lamps, electron (E) beams, and spike methods.

[0110] At 1515, the surface of the substrate can be refreshed by purging the process chamber with a purge gas (e.g., argon (Ar)) to bombard the process chamber with ions and remove modified portions of the substrate. In one embodiment, the process chamber is cleaned between one or more consecutive pairs of rapid thermal pulses. In one embodiment, gas is purged from the process chamber between each consecutive pair of pulses. This enables multiple plasma and / or gas phase processes to be performed within the process chamber. In one embodiment, substrate support cooling is provided during and / or after the pulsed rapid thermal annealing to help maintain the temperature of the substrate base and / or bulk during the pulsed rapid thermal annealing and to help rapidly cool the substrate after the pulsed rapid thermal annealing is performed.

[0111] At 1516, the controller 180 or 208 and / or the rapid thermal pulse controller 182 or 210 determines whether N cycles have been completed. If N cycles have been completed, then operation 1518 is performed, otherwise operation 1508 is performed. At 1518, the controller 180 or 210 may optionally perform a second (or post) annealing operation. At 1519, the controller 180 or 210 may determine whether to perform another process and / or whether to change and / or repeat the current process for the current die. If another process is to be performed, then operation 1504 may be performed, otherwise, if the process is performed using the method shown in FIG. Figure 2 If a laser and lens circuit is used as in the embodiment of FIG. Figure 1If a flash lamp is not used as in the embodiment of the present invention, the method can end at 1522 without performing another process or a change of the current process. If a process is to be performed on another die, operation 1524 is performed, otherwise the method can end at 1522.

[0112] At 1524, the controller 208 moves the mirrors 214, 216 to change the image plane position of the laser beam to be located on different dies on the substrate 112. For example, a 2 cm x 2 cm laser beam can be moved from being located on a first die to being located on a second die. The described method can be performed iteratively to scan the laser beam over tens to hundreds of dies on the substrate. The movement of the mirrors 214, 216 can be synchronized with the pulse repetition rate of the laser 204 to provide one or more shots for each die.

[0113] The above operations are intended as illustrative examples. These operations may be performed sequentially, synchronously, simultaneously, or continuously in different orders during overlapping time periods, depending on the application. In addition, any of these operations may not be performed or may be skipped depending on the implementation and / or sequence of events.

[0114] although Figure 15 The method is described as using Figure 1-2 The system performs ALE, but Figure 1-2 Systems can be used to perform ALD. Heat sources such as flash lamps and lasers can be used to grow a monolayer on a substrate. For example, RTP can be provided before and / or during a deposition operation, and material can be deposited (or grown) rather than removed. Different gases can be provided and maintained in the respective process chambers during ALD to allow for the growth of the monolayer.

[0115] Figure 18 is a block diagram illustrating two exemplary ALE methods for removing a TiN monolayer. Figure 1-2 system to execute Figure 18 The first method includes providing H2 plasma as a pretreatment operation to change the upper portion of the TiN layer or substrate and provide a weakly bonded TiN layer 1800 on the remaining portion 1802 of the TiN layer or substrate. Cl2 plasma is then provided for atomic adsorption to convert the weakly bonded TiN layer 1800 into TiCl x N y Layer 1804. TiCl x N y is a volatile compound. RTP is then performed to remove TiCl x N y Layer 1804.

[0116] For example, the cycle may include: providing H2 plasma for 13 seconds, including providing H2 gas and Ar gas at a flow rate of 90 standard cubic centimeters (sccm) and a pressure of 180 millitorr (mT), respectively; providing Cl2 plasma for 25 seconds, including providing Cl2 at a flow rate of 100 sccm and a pressure of 400 mT; performing a sweep operation for 30 seconds after the atomic adsorption operation and before the RTP operation; and performing the RTP operation, including providing 5 pulses, each pulse being x mJ / cm 2 In one embodiment, x is 21. In one embodiment, the cycle is performed a predetermined number of times (e.g., 30 times). Table 2 below shows this method: exemplary film thicknesses before performing atomic adsorption with Cl2 and / or performing RTP; and exemplary film thicknesses produced by performing atomic adsorption and / or RTP with Cl2.

[0117] Craftsmanship Before (nm) After (nm) ER (angstroms / cycle) Laser RTP only 92.8 89.4 1.1 <![CDATA[Only Cl2]]> 92.8 89.9 1.0 <![CDATA[Cl2 and Laser RTP]]> 92.8 81.2 3.9

[0118] Table 2

[0119] Figure 19 An example graph showing the TiN film thickness for different energy levels is shown. Etching at laser energy greater than or equal to 20 mJ / cm 2 Therefore, etching occurs at 21mJ / cm 2 The power level occurs, range 1906 is lower than ranges 1900, 1902, and 1904.

[0120] Reference again Figure 18 The second method includes providing an O2 plasma as a pre-treatment operation to remove nitrogen oxides (NO x ) to modify the upper portion of the TiN layer or substrate, thereby providing TiO on the remaining portion 1812 of the TiN layer or substrate. x Layer 1810. Then Cl2 plasma is provided to perform atomic adsorption to remove TiO x Layer 1810 is converted into titanium oxychloride (TiOCl x ) layer 1814. TiOClx is a volatile complex. RTP is then performed to remove TiOCl x Layer 1814. For example, one cycle may include: providing O2 plasma for 5 seconds, including providing O2 gas and Ar gas at a flow rate of 90 standard cubic centimeters (sccm) and a pressure of 180 millitorr (mT), respectively; providing Cl2 plasma for 25 seconds, including providing Cl2 at a flow rate of 100 sccm and a pressure of 400 mT; performing a sweep operation for 30 seconds after the atomic adsorption operation and before the RTP operation; and performing the RTP operation, including providing 5 pulses, each pulse being x mJ / cm 2For example, for the second method, the exemplary film thickness before performing the second method is 93 nm, and the exemplary film thickness after performing 100 cycles of the second method is 79.6 nm. The corresponding etch rate may be 1.32 angstroms per cycle. Figure 20 An exemplary graph of TiN film thickness versus different numbers of ALE cycles performed is shown. Ranges of 2000, 2002, 2004 are shown as examples for 0, 50, and 100 cycles performed.

[0121] The two methods described are isotropic ALE processes. In one embodiment, these methods provide an etch rate of 1.5-2.0 angstroms per cycle. The etch rate of 2.0 angstroms per cycle is 10 times faster than the oxidative fluorination etch process of TiN. The etch depth can be controlled by controlling the number of cycles of the method performed and / or the plasma power level. The two methods described above include a light irradiation / pulsed heat source that can achieve isotropic removal during the ALE process. The methods can be modified to perform two anisotropic ALE processes by applying a plasma during RTP and introducing a bias voltage via one or more electrodes in the substrate support. For example, the method can be performed via Figure 1 The bias voltage is provided to the electrodes 118 of the substrate support 110. In addition, the bias power provided to one or more electrodes in the substrate support can be controlled to control the ion directionality to achieve isotropic control.

[0122] Figure 21 Figure 2 is an example graph of TiN film thickness ranges, illustrating different amounts of material removal for different operations performed. TiN film thickness ranges 2100, 2102, 2104, 2106, 2108, 2110, and 2112 are shown for: control; laser RTP (or "laser only") without pretreatment and atomic adsorption; atomic adsorption with Cl2 without pretreatment and laser RTP; H2 plasma pretreatment and laser RTP; O2 plasma pretreatment and laser RTP; H2 plasma pretreatment with flash lamp RTP; and O2 plasma pretreatment with flash lamp RTP. For example, over 30 cycles, the TiN etch rates for H2 plasma pretreatment and laser RTP, O2 plasma pretreatment and laser RTP, H2 plasma pretreatment with flash lamp RTP, and O2 plasma pretreatment with flash lamp RTP were 3.9 Å / cycle, 1.4 Å / cycle, 2.0 Å / cycle, and 2.4 Å / cycle, respectively.

[0123] Figure 22An example of a substrate processing system 2200 is shown that includes an RTP system 2202 including a laser 2204, a lens circuit 2206, and a controller 2208 having an RTP controller 2210. The substrate processing system 2200 may be similar to Figure 2 The substrate processing system 200 operates as described above. The laser 2204 is a heat source that can be pulsed (or modulated) by the RTP controller 2210 during RTP operation based on control signals received from the RTP controller 2210. This can occur during ALE and ALD processes.

[0124] The lens circuit 2206 includes a beam shaping optical device 2212, a current mirror circuit 2213 including a first reflector 2214 and a second reflector 2216, and a telecentric lens assembly 2218. The beam shaping optical device 2212 may include a flat top (or first beam shaping) optical device 2220 and a diffraction (or second beam shaping) optical device 2222. The flat top optical device 2220 is used to convert the laser beam received from the laser 2204 into a flat top beam (e.g., a 2 centimeter (cm) × 2 cm flat top beam), wherein the laser beam has a Gaussian distribution. The temperature profile of the laser beam is also Gaussian. The diffraction optical device 2222 converts the flat top circular beam from the flat top optical device 2220 into a square beam. The square beam has a corresponding uniform temperature distribution on the substrate. The substrate 112 can be set on a substrate support (e.g., Figure 1 on a substrate support 110).

[0125] The laser 2204 can operate in either pulsed or continuous wave (CW) mode. During pulsed mode, the output of the beam shaping optics 2212 can be provided directly to the beam size adjustment device 2226. During pulsed mode, the RTP controller 2210 controls the pulse rate of the laser beam so that the pulse duration is in the picosecond or nanosecond range. When the laser 2204 is operated in CW mode and controlled by the RTP controller 2210, an acousto-optic modulator 2223 may be included. In one embodiment, the RTP controller 2210 generates a radio frequency (RF) control signal that is provided to the acousto-optic modulator 2223. The RF control signal is provided to control the refractive index variation of the crystal of the acousto-optic modulator 2223. The refractive index of the crystal varies based on the frequency of the RF control signal. The laser beam provided from the beam shaping optics 2212 to the acousto-optic modulator 2223 is deflected by the crystal according to the frequency of the RF signal. The crystal acts as a laser shutter, allowing or preventing the laser beam from reaching the beam size adjustment device 2226 and / or the first reflector 2214. In one embodiment, the RTP controller 2210 controls the frequency of the RF control signal so that the continuous wave laser beam emitted from the beam shaping optics 2212 is effectively pulsed (or modulated) by the acousto-optic modulator 2223. The laser beam is pulsed so that the duration of each pulse is in the microsecond or millisecond range. As a result, the use of the acousto-optic modulator 2223 enables the generation of a pulsed laser beam with longer duration pulses to increase heating per pulse.

[0126] The beam size adjustment device 2226 can be disposed between the beam shaping optics 2212 and the first mirror 2214. In one embodiment, the beam size adjustment device 2226 adjusts the size of the square beam to be greater than or equal to the size of the die on the substrate 112. The beam size adjustment device 2226 can be motorized and include a beam expander 2227.

[0127] The RTP controller 2210 and the current mirror circuit 2213 can function as an XY galvanometer scanning system. A first mirror 2214 can be used to move the laser beam across the surface of the substrate 112 in a first (or X) direction. A second mirror 2216 can be used to move the laser beam across the surface of the substrate in a second (or Y) direction. The controller 2208 and / or the RTP controller 2210 can move the mirrors 2214 and 2216 via motors 2230 and 2232.

[0128] Telecentric lens assembly 2218 can include a series of plano-convex lenses 2240, 2242, 2244, 2246. Although a specific number of plano-convex lenses is shown, a different number of plano-convex lenses can be included. The diameters of plano-convex lenses 2240, 2242, 2244, 2246 increase as they approach window assembly 130, such that: the diameter of lens 2242 is greater than the diameter of lens 2240; the diameter of lens 2242 is greater than the diameter of lens 2240; the diameter of lens 2244 is greater than the diameter of lens 2242; and the diameter of lens 2246 is greater than the diameter of lens 2244. Plano-convex lenses 2240, 2242, 2244, 2246 are vertically aligned to have a common centerline 2248. Plano-convex lenses 2240, 2242, 2244, 2246 are retained in a fixed relationship within mold 2250. Plano-convex lenses 2240, 2242, 2244, 2246 direct the laser beam received from second mirror 2216 normal to the surface of substrate 112. Telecentric lens assembly 2218 maintains the laser beam normal to the surface of substrate 112 as it moves across the surface of substrate 112.

[0129] For example, a laser beam emitted from the beam shaping optics 2212, the acousto-optic modulator 2223, and / or the beam size adjustment device 2226 can be focused at the center 2252 of the second mirror 2216 and then directed through the telecentric lens assembly 2218, where the laser beam is collimated and provided to the substrate 112. Focusing the laser light at the input pupil of the second mirror (or lens) 2216 helps provide a collimated beam on the upward-facing surface of the substrate 112.

[0130] For example, the diameter of the laser beam produced by the laser 2204 can be 355 nm. The laser 2204 can be operated in a pulsed mode or a CW mode. The beam shaping optics 2212, the beam size adjustment device 2227, and the telecentric lens assembly 2218 can produce a 2 cm by 2 cm square beam received at the substrate 112. The RTP controller 2210 can move the mirrors 2214, 2216 to perform a 200 Hz scan across the entire surface of the substrate 112. The RTP controller 2210 can scan all dies and / or upward facing surface area (for example, for a substrate with a diameter of 300 mm, the upward facing surface area of ​​the substrate is 2.83×10 5 mm). This can include scanning, for example, 160 dies of a substrate in 1 second. Scanning involves moving the laser beam from die to die and heating each die for a predetermined period of time (e.g., the total time period of one or more pulses of the laser beam).

[0131] The substrate processing system 2200 may include a temperature control system 150 that may be used to control the temperature of the substrate support 110 and substrate 112. The temperature control system 150 may include one or more temperature sensors 156 to sense the temperature of one or more locations or regions of the substrate support 110.

[0132] like Figure 3 The telecentric lens assembly shown may be expensive to implement. It is possible to collimate the laser beam without using a telecentric lens assembly. For example, and with reference to Figure 23 , Figure 3 The telecentric lens assembly 218 can be removed and the reflector 216 moved away from the image plane 304 to collimate the laser beam. To collimate the laser beam and minimize the angle at which the light is directed toward the substrate 112 (or the angle away from the direction orthogonal to the image plane 304), the transmission distance TD between the reflector 216 and the image plane 304 is maximized and / or set to be greater than a predetermined minimum distance. If the light is directed in a direction perpendicular to the image plane 304, ideal laser beam conditions exist to uniformly etch the entire surface of the substrate 112. If the light is directed at an angle within a predetermined small range of orthogonality (e.g., 90°±3°), the laser beam is sufficiently collimated to provide surface etching uniformity above a predetermined minimum uniformity level. To direct the light of the laser beam so that the angle of the light is within a predetermined range, the distance TD is set to be greater than or equal to a predetermined length (e.g., 3 meters). The larger the distance TD, the smaller the angle, and therefore the more collimated the laser beam. Figure 23 It shows (i) when the laser beam is directed toward the center of substrate 112, and (ii) when the laser beam is directed toward the edge of substrate 112. As the angle of incidence 2300 between the two transmissions decreases, the distance between lens 216 and image plane 304 increases.

[0133] In order to reduce the distance between the reflector 216 and the image plane 304 and collimate the laser beam at the same time, a beam folding assembly can be incorporated between the reflector 216 and the image plane 304. The beam folding assembly improves telecentricity. An example of this is shown in FIG. Figure 24 Shown in. Figure 24 An example of a substrate processing system 2400 is shown that includes an RTP system 2402 that includes a laser 2404, a lens circuit 2406, and a controller 2408 having an RTP controller 2410. The substrate processing system 2400 may be similar to Figure 2 The substrate processing system 200 and Figure 22 The substrate processing system 2200 operates as described above. The laser 2404 is a heat source that can be pulsed (or modulated) by the RTP controller 2410 during RTP operation based on control signals received from the RTP controller 2410. This can occur during ALE and ALD processes.

[0134] Lens circuit 2406 includes beam shaping optics 2412, current mirror circuit 2413 including a first mirror 2414 and a second mirror 2416, and a beam folding assembly 2418. Beam shaping optics 2412 may include a flat-top (or first beam shaping) optic 2420 and a diffraction (or second beam shaping) optic 2422. Flat-top optic 2420 is used to convert the laser beam received from laser 2404 into a flat-top beam (e.g., a 2 centimeter (cm) x 2 cm flat-top beam), wherein the laser beam has a Gaussian distribution. The temperature profile of the laser beam is also Gaussian. Diffraction optic 2422 converts the flat-top circular beam emitted from flat-top optic 2420 into a square beam. The square beam has a corresponding uniform temperature distribution on substrate 112. Substrate 112 may be disposed on a substrate support in processing chamber 108.

[0135] The laser 2404 can operate in either pulsed or continuous wave (CW) mode. During pulsed mode, the output of the beam shaping optics 2412 can be directly provided to the beam size adjustment device 2426. During pulsed mode, the RTP controller 2410 can control the pulse rate of the laser beam so that the pulse duration is in the picosecond or nanosecond range. When the laser 2404 operates in CW mode, an acousto-optic modulator 2423 can be included. The acousto-optic modulator 2423 can be controlled by the RTP controller 2410. In one embodiment, the RTP controller 2410 generates an RF control signal that is provided to the acousto-optic modulator 2423. The RF control signal is provided to control the change in the refractive index of the crystal of the acousto-optic modulator 2423. The refractive index of the crystal changes according to the frequency of the RF control signal. The laser beam provided from the beam shaping optics 2412 to the acousto-optic modulator 2423 is deflected by the crystal based on the frequency of the RF signal. The crystal acts as a laser shutter that allows or blocks the laser beam from reaching the beam size adjustment device 2426 and / or the first reflector 2414. In one embodiment, the RTP controller 2410 controls the frequency of the RF control signal so that the continuous wave laser beam emitted by the beam shaping optics 2412 is effectively pulsed (or modulated) by the acousto-optic modulator 2423. The laser beam is pulsed so that the duration of each pulse is in the microsecond or millisecond range. As a result, the use of the acousto-optic modulator 2423 allows the generation of a pulsed laser beam with longer duration pulses to increase the heating per pulse.

[0136] A beam size adjustment device 2426 may be disposed between the beam shaping optics 2412 and the first mirror 2414. The beam size adjustment device 2426 may adjust the size of the square beam to be greater than or equal to the size of the die on the substrate 112. The beam size adjustment device 2426 may be motorized and include a beam expander 2427.

[0137] The RTP controller 2410 and the current mirror circuit 2413 can function as an XY galvanometer scanning system. A first mirror 2414 can be used to move the laser beam across the surface of the substrate 112 in a first (or X) direction. A second mirror 2416 can be used to move the laser beam across the surface of the substrate in a second (or Y) direction. The controller 2408 and / or the RTP controller 2410 can move the mirrors 2414 and 2416 via motors 2430 and 2432.

[0138] The beam folding assembly 2418 may include a set of mirrors for reflecting the received laser beam. The beam folding assembly 2418 may include any number of mirrors. By way of example, four mirrors 2452, 2454, 2456, and 2458 are shown. The mirrors may be of different sizes, positioned at different angles, and located at different locations within the housing 2459. The housing 2459 may have a first (or input) window 2460 and a second (or output) window 2461 through which the laser light is transmitted. In the example shown, three laser beams 2462, 2464, and 2466 are shown; each having its own light beam. The three laser beams are provided at corresponding times and by moving the mirrors 2414 and 2416 to corresponding positions. Any number of laser beams may be generated. In one embodiment, a current mirror circuit is included in the housing 2459. The current mirror circuit 2413 in combination with the beam folding assembly 2418, or the beam folding assembly 2418 alone, may be referred to as a collimating assembly.

[0139] Beam folding assembly 2418 increases the propagation distance of the laser beam from second reflector 2416 to substrate 112 while minimizing the distance between second reflector 2416 and substrate 112. The increased propagation distance allows the laser beam to be collimated before being received by the substrate. This provides for a compact design. Beam folding assembly 2418 is also less expensive to manufacture than a telecentric lens assembly.

[0140] The set of mirrors of the beam folding assembly 2418 are positioned and oriented to direct the laser beam received from the second mirror 2416 to be orthogonal (or within a predetermined angle relative to 90°) to the surface of the substrate 112. The beam folding assembly 2418 maintains the laser beam in this orthogonal or semi-orthogonal relationship with the surface of the substrate 112 as the laser beam moves across the surface of the substrate 112.

[0141] For example, a laser beam emitted from the beam shaping optics 2412, the acousto-optic modulator 2423, and / or the beam size adjustment device 2426 can be focused at the center of the second mirror 2416 and then directed through the beam folding assembly 2418, where the laser beam is collimated and provided to the substrate 112. Focusing the laser light at the input pupil of the second mirror (or lens) 2416 helps provide a collimated beam at the upward-facing surface of the substrate 112.

[0142] By way of example, the diameter of the laser beam produced by the laser 2404 can be 355 nm. The laser 2404 can be operated in a pulsed mode or a CW mode. The beam shaping optics 2412, the beam size adjustment device 2427, and the beam folding assembly 2418 can produce a 2 cm x 2 cm square beam received at the substrate 112. The RTP controller 2410 can move the mirrors 2414, 2416 to perform a 200 Hz scan across the entire surface of the substrate 112. The RTP controller 2410 can scan all dies and / or upward facing surface area (e.g., for a substrate with a diameter of 300 mm, 2.83 x 10 cm of the substrate) within a 1 second period. 5 mm of upwardly directed surface area). This can include scanning, for example, 160 dies of a substrate in 1 second. Scanning includes moving the laser beam from die to die and heating each die for a predetermined period of time (e.g., the total time period of one or more pulses of the laser beam).

[0143] The substrate processing system 2400 may include a temperature control system 150 that may be used to control the temperature of the substrate support 110 and substrate 112. The temperature control system 150 may include one or more temperature sensors 156 to sense the temperature of one or more locations or regions of the substrate support 110.

[0144] The processes of ALD and ALE depend on iteratively performing a first operation A, followed by a second operation B, with a pump / sweep operation performed between operations A and B. This is independent of the type of heat source used. For example, a first gas can be dosed over the entire substrate surface to form a saturated monolayer. Any residual amount of the first gas can then be pumped out of the corresponding processing chamber. The entire substrate surface can then be exposed to a second gas and / or an energy source (such as high-energy ions or ultraviolet photons), and the product (or residual) gas can then be extracted. These operations can then be repeated until a predetermined deposited film thickness is obtained or a predetermined etch depth is reached.

[0145] For laser-based substrate processing, the laser beam is focused onto an area much smaller than the upward-facing surface area of ​​the substrate (e.g., for a 300 mm diameter substrate, the upward-facing surface area is approximately 2800 cm). 2) to heat the surface to a predetermined temperature. Additionally, the amount of time to perform the pulsed laser anneal (a predetermined number of picoseconds or nanoseconds) is orders of magnitude less than the seconds typically required to (i) dose the upper surface of the wafer across the entire wafer or ii) evacuate the gases within the process chamber.

[0146] Thus, by using the implementations disclosed above, it is possible to focus the laser beam to the size of a chip (or die) on a substrate, then step the laser beam onto the surface of the substrate and synchronize the pulses with the amount of time required to reposition the laser beam so that the laser beam is ON when over a chip and OFF when transitioning to the next chip.

[0147] For example, if the chip has an upward-facing surface area of ​​1 cm x 1 cm, the size of the laser beam generated is also 1 cm x 1 cm. For example, the surface area of ​​the substrate can be dosed, then the gas can be pumped out, and then the laser beam can be stepped from one chip to another using one of the substrate processing systems disclosed herein. The laser beam can be pulsed on each chip continuously. After the laser is pulsed on each of the chips in the substrate, the substrate can be dosed again, and the process can be repeated until a predetermined etch depth or a predetermined deposition thickness is reached for each tube core. The laser beam can be stepped to all the chips of the substrate in less than 1-3 seconds, which is similar to the amount of time associated with gas dosing and gas sweep operations. Therefore, the laser annealing time is reduced and the substrate yield is high and inexpensive. This also reduces the time the laser is on and reduces the time ratio of performing the annealing process on the chips of the substrate relative to the amount of time associated with the corresponding dosing and sweeping.

[0148] In one embodiment, the duty cycle of the laser is synchronized with the time it takes to steer the associated laser beam from one die to another. For example, if there are 160 2 cm x 2 cm dies on a substrate, the center of the laser beam is repositioned to leave a distance of slightly more than approximately 2 cm (or the width of the die plus the gap between adjacent dies) between each laser pulse. If the entire substrate is scanned in 1 second, the time associated with each laser pulse cycle is 1 / 160 of a second.

[0149] For example, the entire substrate can be dosed, the gas pumped out of the corresponding process chamber, and the laser stepped from one die to the next, pulsing on each die in turn. The substrate can then be dosed again and the process repeated. This provides a fast annealing process. If laser annealing of the entire substrate surface takes a long time (e.g., 10 minutes), the substrate throughput will be low and expensive. By providing a laser annealing process in which the entire substrate surface is scanned in a short period of time (e.g., 1 second), the time gating items are substrate dose and gas sweep rather than laser annealing.

[0150] Examples provide high-throughput, highly selective ALE with improved layer thickness control. Pulsed laser operation enables in-situ plasma or gas-phase processing. Multiple cycles of surface modification and isotropic removal are performed with nanoscale selectivity and short process times. Rapid pulsed thermal ALE is performed in a single process chamber without thermal budget issues. Telecentric and beam folding examples are disclosed that enable maintaining perpendicular illumination on the substrate surface without beam distortion while providing a substantially uniform temperature distribution across the substrate surface.

[0151] Figure 25 32 shows a substrate processing system 3200 incorporating an RTP system 3202 including a laser 3204, a lens circuit 3206, and a controller 3208 having an RTP controller 3210. The substrate processing system 3200 may be similar to Figure 2 The substrate processing system 200, Figure 22 The substrate processing system 2200 and / or Figure 24 The substrate processing system 2400 operates as described above. The laser 3204 is a heat source that can be pulsed (or modulated) by the RTP controller 3210 during RTP operation based on control signals received from the RTP controller 3210. This can occur during ALE and ALD processes.

[0152] Lens circuit 3206 includes beam shaping optics 3212 and at least one of a reflector 3214 and a polygon scanner 3216. In one embodiment, reflector 3214 is included and polygon scanner 3216 is not included. In another embodiment, reflector 3214 is implemented as a side of polygon scanner 3216. Polygon scanner 3216 can have one or more reflectors. In one embodiment, each side surface of polygon scanner 3216 has a reflector. In the example shown, the polygon scanner has six side surfaces and two end surfaces. The polygon scanner can have any number of sides. In one embodiment, reflector 3214 is provided by a lens such as a lens. Figure 2 、 22, 24. In another embodiment, polygon scanner 3216 is rotated by a motor.

[0153] The motor can be unidirectional or bidirectional, so that the shaft of the motor can be driven in both a forward and reverse direction. The motor can rotate the mirror and / or polygon scanner so that the laser beam is no longer reflected from the first portion of the first mirror, but is instead reflected from the second portion of the first mirror. The shaft of the motor can then be returned to its initial position so that the laser beam is reflected from the first portion of the first mirror, or can be rotated so that the laser beam is reflected from a different mirror. In one embodiment, the motor is unidirectional so that the shaft of the motor rotates in the same direction. Instead of rotating the shaft in the opposite direction and returning to the initial position when rescanning the substrate, the polygon scanner can be rotated so that the laser beam is reflected from the next adjacent mirror on the polygon scanner. This has the same effect as returning to the initial position.

[0154] The beam shaping optics 3212 may include a flat top (or first beam shaping) optics 3220 and a second beam shaping optics 3222. The flat top optics 3220 is used to convert the laser beam received from the laser 3204 into a flat top beam, wherein the laser beam has a Gaussian distribution. The temperature distribution of the laser beam is also Gaussian. The second beam shaping optics 3222 converts the flat top circular beam emitted from the flat top optics 3220 into a linear beam 3224 having an elliptical cross section, such as Figure 26 As shown. The linear beam 3224 can have a Gaussian intensity and / or temperature distribution in a first (or x) direction and a substantially "flat top" or uniform intensity and / or temperature distribution in a second (or y) direction. The length L1 of the cross section of the linear beam 3324 in the y direction can be greater than the diameter of the substrate 112. For example, the length L1 can be 320 mm and the diameter of the substrate can be 300 mm. In one embodiment, the linear beam 3324 (i) has a substantially "flat top" or uniform intensity in a central portion 3300 of the linear beam 3324 and provides a uniform temperature distribution on the surface of the substrate 112, and (ii) has an end portion 3302 where the intensity distribution decreases sharply from the central portion 3300 to the radially outermost edge 3304 of the substrate 112. As Figure 26 As shown, the central portion 3300 of the cross section of the linear beam 3324 has a length L2 that is equal to or close to the diameter of the substrate 112. The substrate 112 may be disposed on a substrate support (e.g., Figure 1 substrate support 110).

[0155] exist Figure 25In the example shown, the polygon scanner 3216 is shown in three rotational positions, two of which are shown by dashed line representations 3216' and 3216". Although the representations 3216' and 3216" are shown to the left and right of the polygon scanner 3216, the polygon scanner is actually fixed and only rotates to scan across the substrate 112. This provides one-dimensional motion of the linear beam across the substrate 112 for fast scanning (i.e., short scan times). Figure 25 An embodiment in which no telecentric lens assembly and / or beam folding assembly is used.

[0156] Laser 3204 can operate in pulsed mode or continuous wave (CW) mode. During pulsed mode, the output of beam shaping optics 3212 can be directly provided to beam size adjustment device 3226. During pulsed mode, RTP controller 3210 can control the pulse rate of the laser beam so that the pulse duration is in the picosecond or nanosecond range. When laser 3204 operates in CW mode, an acousto-optic modulator 3223 can be included. Acousto-optic modulator 3223 can be controlled by RTP controller 3210. In one embodiment, RTP controller 3210 generates an RF control signal, which is provided to ACM 3223. The RF control signal is provided to control the change in the refractive index of the crystal of ACM 3223. The refractive index of the crystal changes according to the frequency of the RF control signal. The laser beam provided to ACM 3223 from beam shaping optics 3212 is deflected by the crystal based on the frequency of the RF signal. The crystal acts as a laser shutter that allows or blocks the laser beam from reaching the beam size adjustment device 3226, the reflector 3214, and / or the polygon scanner 3216. In one embodiment, the RTP controller 3210 controls the frequency of the RF control signal so that the continuous wave laser beam emitted by the beam shaping optics 3212 is effectively pulsed (or modulated) by the acousto-optic modulator 3223. The laser beam is pulsed so that the duration of each pulse is in the microsecond or millisecond range. As a result, the use of the acousto-optic modulator 3223 allows the generation of a pulsed laser beam with longer duration pulses to increase heating per pulse.

[0157] The beam size adjustment device 3226 can be disposed between the beam shaping optics 3212 and the mirror 3214 and / or the polygon scanner 3216. The beam size adjustment device 3226 can adjust the size of the linear beam to be larger than the diameter of the substrate 112. The beam size adjustment device 3226 can be motorized and include a beam expander 3227.

[0158] The RTP controller 3210, the mirror 3214, and / or the polygon scanner 3216 can operate as a one-dimensional scanning system. The mirror 3214 and / or the polygon scanner 3216 can be rotated to move the laser / line beam 3224 across the surface of the substrate 112, for example, in a first (or x) direction. As described above, the controller 3208 and / or the RTP controller 3210 can rotate the mirror 3214 and / or the polygon scanner 3216 via corresponding motors to scan across the surface of the substrate 112. At each location of the linear beam on the surface of the substrate, the linear beam heats a portion of the die of the substrate 112 in the y-direction. One or more pulses can be generated at each location of the linear beam. The linear beam can circulate over the surface multiple times to remove a predetermined thickness (or multiple thicknesses) of material from the substrate 112.

[0159] Figure 26 A cross-sectional view of a circular beam 3310 and a linear beam 3324 is shown. The beam shaping optics 3212 will Figure 25 The circular beam 3310 output by the laser 3204 is converted into a linear beam 3224. The linear beam has an elliptical cross-section and may have a Gaussian distribution in the x-direction and a substantially uniform distribution in the y-direction. For example, the angle of incidence between when the linear beam is directed at the center of the substrate 112 and when the linear beam is directed at a point near the radially outermost edge of the substrate 112 may be 8.53°. The normal energy density of the linear beam at the center position may be 1, and the normal energy density at the radially outermost edge position may be 0.989. The beam size deviation between the two positions may be 1.12 μm.

[0160] Figure 27 The relationship between the linear beam size deviation in the x-direction (or transverse direction) and the distance between the reflector and the substrate surface is shown. The size deviation along the y-direction (or longitudinal direction) is small or non-existent. This relationship diagram can be applied to Figure 25 and Figure 26 The further the reflector 3214 and / or polygon scanner 3216 are from the surface of the substrate 112, the smaller the change in beam size as the linear beam 3224 moves from the center to the radially outermost edge of the substrate 112. Furthermore, the difference in beam size is minimal (e.g., 1 μm) when the reflector 3214 and / or polygon scanner 3216 is 1-3 meters (m) from the substrate surface. Therefore, the substrate 112 can be positioned close to the reflector 3214 and / or polygon scanner 3216.

[0161] The foregoing description is merely illustrative in nature and is in no way intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because other modifications will become apparent when studying the drawings, description and appended claims. It should be understood that one or more steps in the method can be performed in a different order (or simultaneously) without changing the principles of the present disclosure. In addition, although each embodiment is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure can be implemented in the features of any other embodiment and / or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the embodiments described are not mutually exclusive, and the replacement of one or more embodiments with each other remains within the scope of the present disclosure.

[0162] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "next to," "on top of," "above," "below," and "disposed." Unless the relationship between a first and a second element is explicitly described as "direct," when such a relationship is described in the above disclosure, the relationship can be a direct relationship, in which there are no other intervening elements between the first and second elements, but can also be an indirect relationship, in which there are one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the phrase "at least one of A, B, and C" should be construed to mean a logical (A or B or C), using a non-exclusive logical OR, and should not be construed to mean "at least one of A, at least one of B, and at least one of C."

[0163] In some implementations, the controller is part of a system that can be part of the examples above. Such a system can include semiconductor processing equipment that includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems can be integrated with electronic devices for controlling their operation before, during, and after processing of semiconductor wafers or substrates. The electronic device can be referred to as a "controller" that can control various components or subcomponents of one or more systems. Depending on the processing requirements and / or system type, the controller can be programmed to control any process disclosed herein, including the 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 rate settings, fluid delivery settings, position and operation settings, wafer transfer in and out tools and other transfer tools and / or load locks connected to or interfaced with a specific system.

[0164] In general, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits can include chips in the form of firmware that stores 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 can be instructions sent to the controller in the form of various separate settings (or program files) that define operating parameters for performing a particular process on or for a semiconductor wafer or system. In some embodiments, the operating parameters can be part of a recipe defined by a process engineer to complete one or more processing steps during the manufacture of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or the die of the wafer.

[0165] In some implementations, the controller can be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller can be in the "cloud" or all or part of a wafer fab host system that can allow remote access to wafer processing. The computer can enable remote access to the system to monitor the current progress of manufacturing operations, review the history of past manufacturing operations, review trends or performance metrics for multiple manufacturing operations, change parameters of the current process, set processing steps to follow the current process, or start a new process. In some examples, a remote computer (e.g., a server) can provide process recipes to the system via a network (which can include a local network or the Internet). The remote computer can include a user interface that enables the input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters can be specific to the type of process to be performed and the type of tool the controller is configured to interface with or control. Thus, as described above, the controller can be distributed, for example, by including one or more discrete controllers networked together and working toward a common purpose (e.g., process and control as described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber communicating with one or more integrated circuits remotely (e.g., at a platform level or as part of a remote computer), which combine to control the process on the chamber.

[0166] Example systems may include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the manufacture and / or preparation of semiconductor wafers.

[0167] As described above, depending on one or more processing steps to be performed by the tool, the controller can communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a host computer, another controller, or tools used in the material transport of wafer containers to and from tool locations and / or load ports in a semiconductor manufacturing facility.

Claims

1. A substrate processing system comprising: processing room; a substrate support disposed in the processing chamber and configured to support a substrate; a laser configured to generate a laser beam; a lens circuit including beam shaping optics to convert the laser beam from a circular laser beam to a square laser beam; and a collimation assembly comprising a plurality of lenses or mirrors arranged to direct the laser beam toward the substrate to heat exposed material of the substrate, wherein the plurality of lenses or mirrors are configured to direct the laser beam in a direction within a predetermined range of perpendicularity to a surface of the substrate; and A controller is configured to perform a rapid thermal pulse process during an etching process or a deposition process, the rapid thermal pulse process comprising: (i) generating a control signal to modulate the laser beam so as to subject the exposed material to a plurality of thermal energy pulses, and (ii) enabling the exposed material to cool between consecutive thermal energy pulses in the plurality of thermal energy pulses.

2. The substrate processing system of claim 1 , wherein the lens circuit comprises: a flat-top optical device for converting the laser beam from the circular laser beam into a flat-top-shaped laser beam; as well as A diffraction optical device is used to convert the flat top-shaped laser beam into the square laser beam.

3. The substrate processing system according to claim 1 , further comprising a mirror circuit, the mirror circuit comprising a first mirror, a second mirror, a first motor, and a second motor. in, The controller is configured to move the first and second mirrors via the first and second motors to adjust a position of the laser beam on the substrate. 4 . The substrate processing system of claim 1 , further comprising a beam size adjustment device configured to adjust a size of the laser beam before the laser beam is received by the substrate.

5. The substrate processing system according to claim 1, wherein: the collimation assembly includes a telecentric lens assembly comprising a plurality of lenses arranged to direct the laser beam toward the substrate to heat the exposed material; and The plurality of lenses are configured to direct the laser beam in a direction perpendicular to the surface of the substrate.

6. The substrate processing system according to claim 5, further comprising: A reflector circuit comprising a first reflector, a second reflector, a first motor and a second motor, wherein The laser beam is directed toward the first reflecting mirror, The laser beam is directed from the first reflecting mirror to the second reflecting mirror, The laser beam is directed from the second reflector through the telecentric lens assembly and to the substrate; as well as The controller is configured to move the first and second mirrors via the first and second motors to adjust a position of the laser beam on the substrate.

7. The substrate processing system according to claim 6, wherein: The plurality of lenses maintain the laser beam in a perpendicular relationship to the surface of the substrate as the controller adjusts the position of the laser beam on the substrate.

8. The substrate processing system according to claim 5, wherein: The processing chamber is an inductively coupled plasma chamber or a remote plasma source connected chamber; and The telecentric lens assembly is positioned above a dielectric window of the processing chamber.

9. The substrate processing system according to claim 5, wherein: The plurality of lenses are plano-convex lenses.

10. The substrate processing system according to claim 5, wherein: The plurality of lenses have different diameters.

11. The substrate processing system according to claim 10, wherein: The plurality of lenses are arranged in series, including a first lens and a last lens; The diameters of the plurality of lenses increase from the first lens to the last lens; as well as The laser beam is received at the first lens and output from the last lens to the substrate.

12. The substrate processing system according to claim 1, wherein: the collimation assembly comprising a beam folding assembly including a plurality of mirrors arranged to direct the laser beam toward the substrate to heat the exposed material, wherein the plurality of lenses are configured to direct the laser beam in a direction perpendicular to the surface of the substrate; and The plurality of mirrors are arranged to reflect and guide the laser beam in a direction within a predetermined range perpendicular to the surface of the substrate.

13. The substrate processing system of claim 1, wherein the controller is configured to control the laser to pulse the laser beam at a predetermined frequency.

14. The substrate processing system of claim 1 , further comprising a gas delivery system configured to supply process gas to the processing chamber. wherein the controller is configured to control the gas delivery system and the laser to iteratively perform an isotropic atomic layer etching process, comprising During the iterative process of the isotropic atomic layer etching process, pretreatment, atomic adsorption and pulsed thermal annealing are performed. During the atomic adsorption, the surface of the substrate is exposed to the process gas including a halogen species, the halogen species being selectively adsorbed onto the exposed material of the substrate to form a modified material, and During the pulsed thermal annealing, laser pulses are turned on and off multiple times within a predetermined time to expose and remove the modified material.

15. The substrate processing system of claim 1 , further comprising an acousto-optic modulator configured to receive the laser beam, wherein: The controller is configured to generate a radio frequency signal; The laser is configured to operate in continuous mode; and The AOM is configured to switch between allowing the laser beam to pass to the plurality of lenses or mirrors and preventing the laser beam from passing to the plurality of lenses or mirrors at a predetermined frequency based on the radio frequency signal.

16. The substrate processing system of claim 15, wherein: the collimation assembly comprising a beam folding assembly including a plurality of mirrors arranged to direct the laser beam toward the substrate to heat the exposed material, wherein the plurality of lenses are configured to direct the laser beam in a direction perpendicular to the surface of the substrate; and The plurality of mirrors are arranged to reflect and guide the laser beam in a direction within a predetermined range perpendicular to the surface of the substrate.

17. The substrate processing system of claim 15, further comprising a gas delivery system configured to supply a process gas to the processing chamber. in, The controller is configured to control the gas delivery system and the laser to iteratively perform an isotropic atomic layer etching process, which includes During the iterative process of the isotropic atomic layer etching process, pretreatment, atomic adsorption and pulsed thermal annealing are performed. During the atomic adsorption, the surface of the substrate is exposed to the process gas including a halogen species, the halogen species being selectively adsorbed onto the exposed material of the substrate to form a modified material, and During the pulsed thermal annealing process, the radio frequency signal is generated to modulate the laser beam within a predetermined time period to expose and remove the modified material.

18. The substrate processing system of claim 1, further comprising actively cooling the exposed material between successive ones of the plurality of thermal energy pulses.

19. The substrate processing system of claim 1, wherein the controller is configured to actively cool the substrate at least one of during and after a rapid thermal annealing process.

20. The substrate processing system of claim 1, wherein the controller is configured to subject the exposed material to a plurality of high temperature pulses and a plurality of low temperature pulses within a time period of 3-10 seconds.

21. The substrate processing system of claim 1, wherein the controller is configured to actively heat the exposed material from an initial temperature to a temperature greater than 500°C and then cool the exposed material back to the initial temperature in less than 1 second.

Images