KR102454199B1 - Inline Chamber Metrology - Google Patents

Abstract

Embodiments of the present disclosure relate to inspection of substrates undergoing vacuum processing. In one embodiment, the processing chamber comprises a first view port through which an electromagnetic radiation emitter may illuminate a substrate within the processing chamber, a second view port through which a detector may detect electromagnetic radiation scattered from the substrate, an electromagnetic radiation emitter , and a detector.

Description

Inline Chamber Metrology

Embodiments of the present disclosure generally relate to reduced pressure treatment systems and treatment techniques. More particularly, embodiments of the present disclosure relate to techniques for direct inline monitoring of substrates in reduced pressure processing systems.

BACKGROUND Semiconductor substrates are processed for a wide variety of applications including the fabrication of integrated devices and microdevices. One technique for processing substrates involves exposing the substrate to gases at reduced pressures, and causing the gases to deposit a material, such as a dielectric material or a conductive metal, on the surface of the substrate. For example, epitaxy is a deposition process that can be used to grow a thin, high purity layer of silicon or germanium, often on the surface of a substrate (eg, a silicon wafer). The material flows, in a cross-flow chamber, a process fluid (eg, a mixture of precursor gases and carrier gases) across and parallel to a surface of a substrate positioned on a support, (eg, a process fluid) by heating the process fluid to high temperatures) by decomposing the process fluid and depositing material from the process fluid on the surface of the substrate.

At various times during processing of the substrate, the quality of the deposited film may be inspected and/or measured. Previously known techniques for inspecting and/or measuring a substrate involve removing the substrate from a processing chamber and placing the substrate in an instrument for inspecting and/or measuring the substrate. Removal of the substrate from the processing chamber will result in gases entering the processing chamber, possibly requiring the processing chamber to be evacuated by a vacuum pump before processing (of that substrate or other substrates) in the chamber can continue. can

A need exists for a means for inspecting and/or measuring a substrate undergoing processing in a processing system without removing the substrate from the high-vacuum environment of the processing system in order to improve the throughput of processing chambers and the quality of the produced substrates. do.

An apparatus for processing a substrate is provided. The apparatus generally includes a processing chamber body having a first view port and a second view port, a supply in communication with the processing chamber body for providing a process fluid, a vacuum pump in connection with the processing chamber body, and a substrate support in the processing chamber body. , an electromagnetic radiation emitter operable to illuminate a substrate on the substrate support through the first view port, and a detector operable to detect electromagnetic radiation scattered from the substrate through the second view port.

A system for processing a substrate is provided. A system generally includes: a processing chamber having a first slit valve opening configured to allow passage of a substrate therethrough and a second slit valve opening configured to allow passage of a substrate therethrough; a first slit valve operable to open and close a first slit valve opening of the processing chamber, wherein the first slit valve is operable to create a hermetic seal when closed; a second slit valve operable to open and close a second slit valve opening of the processing chamber, wherein the second slit valve is operable to create a hermetic seal when closed; a load-lock having a transfer slit valve opening aligned with a second slit valve opening of the processing chamber, a load-lock port, and a substrate support; and a mechanical arm having an encased probe, the mechanical arm operable to access the interior of the load-lock through the load-lock port, the mechanical arm operable to direct an instrument in the embedded probe with the substrate on the substrate support. operable to move in proximity, the embedded probe having an emitter operable to emit electromagnetic radiation for illuminating the substrate, and the embedded probe having a detector operable to detect electromagnetic radiation scattered from the substrate.

In such a way that the above-mentioned features of aspects of the present disclosure may be understood in detail, a more specific description of the aspects briefly summarized above may be made with reference to embodiments, some of which may be understood in the accompanying drawings. are exemplified in It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present disclosure and are not to be regarded as limiting the scope of the present disclosure, as the present disclosure may admit to other equally effective embodiments. because it can
1A and 1B illustrate cross-sectional views of a reduced pressure processing chamber in accordance with aspects of the present disclosure.
2 illustrates an example processing system in accordance with certain aspects of the present disclosure.
3 illustrates a schematic isometric view of an exemplary load-lock in accordance with aspects of the present disclosure;
4 illustrates a schematic isometric view of a processing chamber in accordance with aspects of the present disclosure.
5 is a set of graphs 500 illustrating monitoring of atomic layer deposition, in accordance with aspects of the present disclosure.
6 is a schematic diagram of an exemplary sum frequency generation (SFG) spectroscopy monitoring system configured to measure a substrate during processing, in accordance with aspects of the present disclosure.
7 is a schematic diagram of an exemplary substrate processing blade in accordance with aspects of the present disclosure.
To facilitate understanding, the same reference numbers have been used wherever possible to designate like elements common to the drawings. It is contemplated that elements disclosed in one embodiment may be beneficially utilized in other embodiments without specific recitation.

To measure layer thickness and layer uniformity of a substrate undergoing processing in a processing system, without removing the substrate from the high-vacuum environment of the processing system, and/or to detect defects in layers and interfaces between layers of a substrate and/or Methods and apparatus are provided for inspecting a substrate to/or perform chemical characterization. The methods and apparatus enable measurement and/or inspection of a substrate without breaking a vacuum in the processing chamber by measuring and/or inspecting the substrate within the processing chamber or in a load-lock chamber coupled to the processing chamber.

One embodiment disclosed herein is a load-lock chamber coupled to a processing system. The load-lock chamber has a mechanical arm with an embedded probe having one or more instruments that can be used to inspect and/or measure the properties or presence of particles on a substrate. The substrate may be removed from the processing chamber and moved into a load-lock, where one or more instruments inspect and/or measure the substrate. The pressure in the load-lock is maintained at a level similar to that of the processing system or processing chamber, allowing measurement and inspection of substrates without breaking the vacuum in the processing chamber.

In another embodiment, a plurality of view ports are arranged on the processing chamber. Lasers, x-ray emitters, and/or other electromagnetic radiation emitters may illuminate the substrate through the first view port in the processing chamber, and the scattered radiation from the substrate exits the processing chamber through the second view port. may be detected, collected, and/or measured by instruments outside the processing chamber. A substrate may be inspected and/or measured while the substrate is within the processing chamber without breaking the vacuum of the processing chamber.

As used herein, radiation “scattered” from a substrate refers to radiation that is reflected from the substrate, refracted from the substrate, emitted from the substrate as a result of illumination, and/or transmitted through the substrate.

BACKGROUND Semiconductor substrates are processed for a wide variety of applications including the fabrication of integrated devices and microdevices. As noted above, one technique for processing substrates is to expose the substrate to gases at reduced pressures, and cause the gases to deposit a material, such as a dielectric material or a conductive metal, on the surface of the substrate. includes doing For example, epitaxy is a deposition process that can be used to grow a thin, high purity layer of silicon or silicon dioxide, often on the surface of a substrate (eg, a silicon wafer). The material flows, in a cross-flow chamber, a process fluid (eg, a mixture of precursor gases and carrier gases) across and parallel to the surface of a substrate positioned on a support (eg, heats the process fluid to high temperatures) ) by dissolving the process fluid and depositing material from the process fluid on the surface of the substrate. Substrates processed according to the above epitaxy techniques may be measured and/or inspected in a processing chamber or in a load-lock, as described in more detail below.

Disclosed embodiments are atomic layer deposition (ALD), chemical vapor deposition (CVD), etching, plasma enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), dielectric deposition, polymer layer deposition, and selective removal process (SRP). ) can be used with techniques for processing substrates, including but not limited to.

1A illustrates a schematic cross-sectional view of an exemplary processing chamber 100 with components in position for processing, in accordance with aspects of the present disclosure. The processing chamber shown is an epitaxial chamber. The process chamber 100 is used to process one or more substrates (eg, perform epitaxial deposition on the one or more substrates), including the deposition of material on a top surface of the substrate 108 . The processing chamber 100 includes, among other components, radiant heat lamps 102 for heating a backside 104 of a substrate support 106 (eg, a susceptor) disposed within the processing chamber 100 . contains an array. In some embodiments, an array of radiant heating lamps is disposed above the upper dome 128 in addition to the array shown below the lower dome. The substrate support 106 may be a disk-shaped substrate support 106 without any central opening as shown, or it may be a ring-shaped substrate support.

1B illustrates a schematic side view of the processing chamber 100 taken along line 1B - 1B of FIG. 1A . Liner assembly 163 and circular shield 167 have been omitted for clarity. The substrate support may be a disk-shaped substrate support 106 as shown in FIG. 1A , or an edge of the substrate to facilitate exposure of the substrate to thermal radiation of the lamps 102 , as shown in FIG. 1B . It may be a ring-shaped substrate support 107 for supporting the substrate from.

1A and 1B , a substrate support 106 or 107 is positioned within the processing chamber 100 between the upper dome 128 and the lower dome 114 . An upper dome 128 , a lower dome 114 , and a base ring 136 disposed between the upper dome 128 and the lower dome 114 define the interior region of the processing chamber 100 . Generally, the central portions of upper dome 128 and lower dome 114 are formed of an optically transparent material such as quartz. The interior region of the processing chamber 100 is generally divided into a process region 156 and a purge region 158 .

A substrate 108 (not to scale) may be moved into the processing chamber 100 through the load port 103 and positioned on the substrate support 106 . The loading port 103 is obscured by the substrate support 106 in FIG. 1A , but is visible in FIG. 1B .

According to one embodiment, the substrate support 106 is supported by a central shaft 132 , which may directly support the substrate support 106 as shown in FIG. 1A . According to another embodiment, the central shaft 132 supports the disk-shaped substrate support 107 with arms 134 , as shown in FIG. 1B .

According to one embodiment, the processing chamber 100 also includes a lamphead 145 that supports the array of lamps 102 and cools the lamps 102 during and/or after processing. Each lamp 102 is coupled to an electrical distribution board (not shown) that supplies electricity to each lamp 102 .

According to one embodiment, the processing chamber 100 also includes one or more optical pyrometers 118 that measure temperatures within the processing chamber 100 and on the surface of the substrate 108 . A controller (not shown) controls the distribution of electricity from the electrical distribution board to the lamps 102 . The controller also controls the flows of cooling fluids within the processing chamber 100 . The controller controls the temperatures within the processing chamber by varying the voltage from the electrical distribution board to the lamps 102 and changing the flows of cooling fluids.

A reflector 122 is disposed over the upper dome 128 to reflect the substrate 108 and infrared light emitted from the upper dome 128 back to the processing chamber 100 . The reflector 122 is secured to the upper dome 128 using a clamp ring 130 . The reflector 122 has one or more connection ports 126 that are connected to a source of cooling fluid (not shown). The connection ports 126 are connected to one or more passageways (not shown) in the reflector such that a cooling fluid (eg, water) can circulate within the reflector 122 .

According to one embodiment, the processing chamber 100 includes a process fluid inlet 174 connected to a process fluid supply 172 . The process fluid inlet 174 is generally configured to direct a process fluid (eg, trimethyl aluminum (TMA) or silane (SiH ₄ )) across the surface of the substrate 108 . The process chamber also includes a process fluid outlet 178 located on the side of the process chamber 100 opposite the process fluid inlet 174 . Process fluid outlet 178 is coupled to vacuum pump 180 .

According to one embodiment, the processing chamber 100 includes a purge gas inlet 164 formed in a sidewall of the base ring 136 . A purge gas source 162 supplies a purge gas to the purge gas inlet 164 . When the processing chamber 100 includes a circular shield 167 , the circular shield 167 is disposed between the process fluid inlet 174 and the purge gas inlet 164 . Process fluid inlet 174 , purge gas inlet 164 , and process fluid outlet 178 are shown for purposes of illustration, and the location, size, and number of fluid inlets and outlets, etc., on the substrate 108 . It can be tailored to facilitate uniform deposition of material.

The substrate support is shown in a position that permits processing of a substrate within the processing chamber 100 . The central shaft 132 , the substrate support 106 or 107 , and the arms 134 may be lowered by an actuator (not shown). A plurality of lift pins 105 pass through the substrate support 106 or 107 . Lowering the substrate support to a stowed position below the processing position causes the lift pins 105 to contact the lower dome 114 , pass through holes in the substrate support 106 and from the substrate support 106 to the substrate 108 . to be able to elevate A robot (not shown in FIG. 1 , but referring to robot 208 in FIG. 2 ) then enters the processing chamber 100 through the loading port 103 to engage the substrate 108 and remove the substrate. A robot or other robot that has removed the substrate 108 enters the processing chamber through the load port 103 to place the unprocessed substrate on the substrate support 106 . The substrate support 106 is then raised to a processing position by an actuator to place the unprocessed substrate in a position for processing.

According to one embodiment, processing of the substrate 108 in the processing chamber 100 includes inserting the substrate through the loading port 103 , placing the substrate 108 on the substrate support 106 or 107 . elevating the substrate supports 106 and 107 and the substrate 108 to a processing position, heating the substrate 108 using lamps 102 , a process fluid 173 across the substrate 108 . and rotating the substrate 108 . In some cases, the substrate may also be raised or lowered during processing.

In accordance with some aspects of the present disclosure, epitaxial processing in the processing chamber 100 includes controlling the pressure within the processing chamber 100 to be below atmospheric pressure. According to one embodiment, the pressure in the processing chamber 100 is reduced to approximately 10 torr to 80 torr. According to another embodiment, the pressure within the processing chamber 100 is reduced to approximately 80 torr to 300 torr. According to one embodiment, the vacuum pump 180 is activated to reduce the pressure in the processing chamber 100 prior to and/or during processing.

Process fluid 173 is introduced into process chamber 100 from one or more process fluid inlets 174 and exits process chamber 100 through one or more process fluid outlets 178 . Process fluid 173 deposits one or more materials on substrate 108 , such as through thermal decomposition, or other reactions. After depositing the materials on the substrate 108, effluents (ie, waste gases) 166 and 175 are formed from the reactions. The effluents 166 and 175 exit the processing chamber 100 through the process fluid outlets 178 .

When processing of the substrate 108 is complete, the processing chamber 100 provides a process fluid 173 and an effluent 166 by introducing a purge gas 165 (eg, hydrogen or nitrogen) through the purge gas inlets 164 . , 175) is purged. Purge gas 165 may be introduced through process fluid inlets 174 instead of or in addition to purge gas inlets 164 . Purge gas 165 exits the processing chamber through process fluid outlets 178 .

Exemplary Inline Chamber Metrology

In embodiments of the present disclosure, a substrate may be processed in a processing chamber and inspected and/or measured without breaking the vacuum of the processing chamber. In one embodiment, the load-lock chamber is connected to the processing chamber via a valve. A load-lock has a mechanical arm with an embedded probe having one or more instruments that can be used to inspect and/or measure a substrate. The substrate may be removed from the processing chamber and passed through a valve into a load-lock, where one or more instruments inspect and/or measure the substrate. The pressure in the load-lock is maintained at or lowered to a level similar to the pressure in the processing chamber, allowing measurement and inspection of the substrate without breaking the vacuum in the processing chamber. The substrate may then be returned to the processing chamber for further processing, and parameters of the additional processing (eg, temperature or gas flow rate) are determined based on measurements and inspections occurring at the load-lock.

Measurement and inspection techniques that may be used with a load-lock in accordance with aspects of the present disclosure include confocal fluorescence microscopy and imaging; reflection of infrared, ultraviolet, and visible radiation, including elliptical polarization; Raman scattering; tip-enhanced Raman scattering; surface plasmon polariton-enhanced Raman scattering; second harmonic; sum frequency spectroscopy; atomic force microscopy (AFM); scanning tunneling microscopy (STM); terahertz or millimeter-wave injections; and x-ray fluorescence (XRF).

In another embodiment, a plurality of view ports are arranged on the process chamber. Lasers, x-ray emitters, and/or other electromagnetic radiation emitters may illuminate the substrate through the first view port in the processing chamber, and the scattered (eg, reflected or refracted) radiation from the substrate is the second It may exit the processing chamber through the view port and be detected, collected, and/or measured by instruments outside the processing chamber. A substrate may be inspected and/or measured while the substrate is within the processing chamber without breaking the vacuum of the processing chamber.

Measurement and inspection techniques that may be used with view ports arranged on a processing chamber in accordance with aspects of the present disclosure include confocal fluorescence microscopy and imaging; reflection of infrared, ultraviolet, and visible radiation, including elliptical polarization; Raman scattering; second harmonic; sum frequency spectroscopy; terahertz or millimeter-wave injections; and x-ray fluorescence (XRF).

2 is a plan view illustrating an exemplary processing system 200 in accordance with an embodiment of the present disclosure. The processing system 200 includes a load-lock chamber 204 , a transfer chamber 206 , a processing (eg, tool and material processing or substrate processing) robot 208 within the transfer chamber 206 , a first CVD processing chamber ( 210 , a second CVD processing chamber 212 , a control station 214 , an ALD processing chamber 216 , and a mask chamber 218 . The first CVD processing chamber 210 , the second CVD processing chamber 212 , the ALD processing chamber 216 , and the associated hardware of each chamber preferably include, for example, one or more process-compatible materials, such as, for example, formed of aluminum, anodized aluminum, nickel plated aluminum, stainless steel, quartz, and combinations and alloys thereof. The first CVD processing chamber 210 , the second CVD processing chamber 212 , and the ALD processing chamber 216 may be round, rectangular, or as required by the shape of the substrate to be coated and other processing requirements; or other shapes.

The transfer chamber 206 includes sidewalls adjacent the load-lock chamber 204 , the first CVD processing chamber 210 , the second CVD processing chamber 212 , the ALD processing chamber 216 , and the mask chamber 218 . slit valve openings 221 , 223 , 225 , 227 , 229 . The processing robot 208 is positioned and configured to insert the substrate processing blade 209 and/or one or more other tools through each of the slit valve openings 221 , 223 , 225 , 227 , 229 into an adjacent chamber. . That is, the processing robot moves the load-lock chamber 204 through the slit valve openings 221 , 223 , 225 , 227 , 229 in the walls of the transfer chamber 206 adjacent each of the other chambers to the first CVD process. Tools may be inserted into the chamber 210 , the second CVD processing chamber 212 , the ALD processing chamber 216 , and the mask chamber 218 . According to aspects of the present disclosure, a substrate processing blade, also referred to herein as a “blade,” may be equipped with substrate monitoring equipment. An example of such a blade is described below with reference to FIG. 7 . The slit valve openings 221 , 223 , 225 , 227 , 229 are slit to allow access to the interiors of adjacent chambers when a substrate, tool, or other article is to be inserted into or removed from one of the adjacent chambers. It is selectively opened and closed using valves 220 , 222 , 224 , 226 , 228 .

The transfer chamber 206 , the load-lock chamber 204 , the first CVD processing chamber 210 , the second CVD processing chamber 212 , the ALD processing chamber 216 , and the mask chamber 218 include a vacuum system ( one or more apertures (not shown) in fluid communication with, for example, a vacuum pump. Apertures provide an outlet for gases in the various chambers. In some embodiments, the chambers are each connected to a separate independent vacuum system. In still other embodiments, some of the chambers share vacuum systems, while other chambers have separate, independent vacuum systems. Vacuum systems may include vacuum pumps (not shown) and throttle valves (not shown) to regulate the flows of gases through the various chambers.

According to aspects of the present disclosure, the first CVD processing chamber 210 may be connected to the load-lock 211 via a valve 215 . The load-lock 211 may have a mechanical arm with an embedded probe having one or more instruments that may be used to inspect and/or measure a substrate (see FIG. 3 ). The substrate may be removed from the first CVD processing chamber 210 and passed through a valve 215 into a load-lock 211 , where one or more instruments inspect and/or measure the substrate. The instruments include a confocal fluorescence microscope and imaging system; one or more infrared, ultraviolet, and/or visible light lasers; one or more charge coupled device (CCD) detectors; one or more mercury cadmium telluride (MCT) detectors; one or more indium gallium arsenide (InGaAs) detectors; mechanical probes with tips for tip-enhanced Raman scattering; atomic force microscope probe; scanning tunneling microscope probe; terahertz or millimeter-wave transceiver antennas; and one or more of an x-ray emitter and a detector. The mechanical arm, embedded probe, and instruments are described in more detail below with reference to FIG. 3 . The pressure in the load-lock 211 is lowered to or maintained at a level similar to that of the first CVD processing chamber 210 , thereby measuring and inspecting the substrate without breaking the vacuum of the first CVD processing chamber 210 . can become possible

Similarly, the second CVD processing chamber 212 may be coupled to the load-lock 213 via a valve 218 , and the ALD processing chamber 216 may be coupled to the load-lock 217 via a valve 219 . can Each of the load-locks 213 and 217 may have a mechanical arm having an embedded probe with one or more instruments that may be used to inspect and/or measure a substrate (see FIG. 3 ). As described above, the substrate may be removed from the second CVD processing chamber 212 and passed through the valve 218 into the load-lock 213 without breaking the vacuum of the second CVD processing chamber 212 . . As also noted above, the substrate may be removed from the ALD processing chamber 216 and passed through the valve 219 into the load-lock 217 without breaking the vacuum of the ALD processing chamber 216 . Once within the load-lock 213 or 217 , the probe's instruments can measure and/or inspect the substrate without breaking the vacuum of the second CVD processing chamber 212 or the ALD processing chamber 216 .

3 illustrates a schematic isometric view of an exemplary load-lock 300 in accordance with aspects of the present disclosure. The load-lock 300 may be an example of the load-locks 211 , 213 , and 217 shown in FIG. 2 . A mechanical arm 302 having an embedded probe 304 may access the substrate 306 through the load-lock port 308 . The substrate 306 may rest on a substrate support 310 (eg, a substrate support blade or pedestal) in a load-lock. The probe may include optical fiber or metallic cables for delivering electromagnetic radiation (eg, infrared, ultraviolet, visible laser light, millimeter-wave, or x-rays) from laser sources or other emitters to a substrate. Additionally or alternatively, the probe may include one or more laser sources, terahertz or millimeter-wave transceiver antennas, and x-ray emitters. The probe may also include one or more charge coupled device (CCD) detectors, mercury cadmium telluride (MCT) detectors, indium gallium arsenide (InGaAs) detectors, mechanical probes with tips for tip-enhanced Raman scattering, atomic force microscope probes. , scanning tunneling microscope probes, x-ray detectors, and/or other types of instruments for measuring and/or inspecting the substrate. The load-lock 300 may also include one or more turbo vacuum ports for evacuating gases (eg, process fluids that may enter the load-lock from the processing chamber) from the load-lock 300 . .

Because the mechanical arm 302 can move the probe 304 very close to the substrate, both near-field and far-field inspection techniques are suitable for performing within the load-lock 300 .

According to aspects of the present disclosure, the probe 304 undergoes limited outgassing when exposed to a vacuum to prevent contamination of the substrate from outgassing from the materials of the probe (eg, fiber optic strands). It may be embedded in a material (eg, quartz). Instruments that require in close proximity to or contact with the substrate (e.g., mechanical probe tips for tip-enhanced Raman scattering, atomic force microscopy, or scanning tunneling microscopy) are used in materials that undergo limited outgassing when exposed to vacuum. may not be purchased. Instead, instruments that require close proximity to or contact with the substrate may be constructed of materials (eg, steel) that undergo limited outgassing when exposed to a vacuum.

4 illustrates a schematic isometric view of a processing chamber 400 (eg, an ALD chamber) having a plurality of view ports 402 and 404 , in accordance with aspects of the present disclosure. The view ports may be made of quartz or other materials translucent to electromagnetic radiation 424 and 426 (eg, infrared light, ultraviolet light, visible light, x-rays, and/or millimeter-wave radiation). The first view port 402 may be positioned such that illumination of the substrate 406 by electromagnetic radiation may occur at a large grazing angle (ie, an angle measured from normal to the upper surface of the substrate). The second view port 404 may be positioned to enable the detectors 430 to receive and/or detect electromagnetic radiation 432 scattered from the substrate at an angle similar to a large grazing angle. The processing chamber 400 may represent the processing chamber 100 shown in FIGS. 1A and 1B . The processing chamber may be connected to a process fluid supply 472 through one or more process fluid inlets 474 and may include a process fluid outlet 478 connected to a vacuum pump 480 . The substrate 406 may rest on a substrate support 410 (eg, a substrate support blade or pedestal) in a load-lock. The substrate support 410 may be heated if desired for the performance of the processing chamber.

One or more lasers (eg, infrared, ultraviolet, visible spectrum, or x-ray lasers) 420 , 422 or other beams of electromagnetic radiation 424 , 426 emitters illuminate the substrate 406 through the view port 402 . can do. As illustrated, the lasers are a femtosecond-picosecond (fs-ps) pulsed visible laser having a wavelength in the range of 800 nanometers (nm), and an fs-ps pulse having a wavelength in the range of 1-4 micrometers (μm). type mid-infrared (mid-IR) laser, but the disclosure is not so limited and emitters of other wavelengths may be used. Lasers and other emitters may be mounted to the load-lock so that electromagnetic radiation emitted by the emitters illuminates the substrate at a consistent angle. Mounts of lasers and other emitters may be moved using one or more actuators (not shown) to cause radiation to raster across the surface of the substrate in a controlled and reproducible manner during measurement and inspection of the substrate. One or more mirrors 442A and 442B, half-wave plates 444A and 444B, polarizers 446A and 446B, and lenses (eg, focusing lenses) 448A and 448B are moved by actuators (not shown) to It can cause radiation to raster across the surface of the substrate. Additionally or alternatively, electromagnetic radiation from the emitters may be directed by fiber optic cables or other conduits, the cables and/or conduits having actuator(s) to cause the radiation to raster across the surface of the substrate. ) is moved by

Electromagnetic radiation 432 scattered from the substrate as a result of illumination of the substrate (eg, reflected or refracted) may exit the processing chamber 400 through the view port 404 . One or more apertures 450 , collimator 452 , polarizer 454 , mirror 456 , filter 458 , and lens 460 direct electromagnetic radiation 432 to one or more charge coupled device (CCD) detectors ( 430), mercury cadmium telluride (MCT) detectors, indium gallium arsenide (InGaAs) detectors, spectrometers, and other types of instruments for measuring and/or inspecting substrates. CCD detectors, MCT detectors, InGaAs detectors, spectrometers, and other instruments may detect and/or measure electromagnetic radiation 432 exiting the view port 404 to determine measurements and other data relating to the substrate. have. Detectors or other instruments may be mounted to the load-lock such that electromagnetic radiation scattered from the substrate is measured or detected at a consistent angle. Mounts of detectors and other instruments may include one or more actuators (not shown) to cause the detectors and other instruments to receive radiation scattered from the substrate in response to the emitters being rasterized across the substrate during measurement and inspection of the substrate. can be moved using Additionally or alternatively, the apertures 450 , the collimators 452 , the polarizers 454 , the mirrors 456 , the filters 458 , and the lenses 460 may provide electromagnetic radiation 432 . may be moved through the actuators to direct the to detectors and/or instruments.

The substrate support 410 may be moved within the processing chamber as part of the measurement and inspection of the substrate. For example, the substrate support 410 may be configured to move the substrate within the processing chamber 400 such that one or more beams 424 , 426 entering through the view port 402 are scanned (eg, rasterized) across the surface of the substrate. can Additionally or alternatively, a scanning galvano mirror may be used to scan the beams from the emitters across the surface of the substrate. The galvano mirror may be located within the processing chamber 400 or located outside the processing chamber 400 .

Although the embodiment shown in FIG. 4 shows beams scanning the upper surface of the substrate 406 , the present disclosure is not so limited. According to aspects of the present disclosure, the substrate support 410 may have a cut portion or be translucent (eg, prism) to the beams, and the view ports 402 and 404 allow the beams to scan the lower surface of the substrate. can be arranged to do so.

According to aspects of the present disclosure, second harmonic generation (SHG) and sum frequency generation (SFG) spectroscopy are used to treat treated surfaces such as ALD, CVD, PECVD, PVD, dielectric deposition, polymer layer deposition, and SRP to monitor the deposited surfaces. SFG spectroscopy probes the secondary molecular hyperpolarizability of a material, indicating which modes are active in a non-centrosymmetric medium. SFG and SHG are second-order nonlinear optical processes, where two incoming photons interact with each other and with the surface when they are spatially and temporally superimposed at a medium surface or interface to have a frequency as the sum of the frequencies of the two incoming photons. Generates 1 photon. When two incoming photons are from the same source (and thus, the same frequency), the resulting process is referred to as second harmonic generation (SHG). When two incoming photons have different frequencies, the resulting optical process is referred to as sum frequency generation (SFG). These secondary optical processes follow the conservation of photon energies and momentum. Conservation of photon momentum makes the processes highly directional, so that SFG or SHG photons can be spatially separated from incoming photons or from other photons from other non-linear optical processes. SFG and SHG are also highly surface sensitive processes, as second-order hyperpolarizations are only active in non-centrosymmetric media, e.g., for molecules that do not possess interfaces, surfaces, or even centers of symmetry. See, eg, Nature 337(6207): pp. 519-525, 1989). For example, SFG spectroscopy can be used to monitor the atomic layer deposition of hydrogen (H ₂ ) on platinum by measuring the intensity of specific wavenumbers associated with platinum-hydrogen bonds, as illustrated with reference to FIG. 5 below. SFG spectroscopy can also be used to monitor atomic layer deposition of aluminum oxide/silicon oxide (AlO _x /SiO _x ) on silicon substrates by measuring the intensity of specific wavenumbers associated with AlO _x bonds (e.g., https:// See E. Kessels et al., Journal of Vacuum Science & Technology A 35, 05C313 (2017), available at doi.org/10.1116.4993597).

5 is a graph 500 illustrating curves illustrating monitoring of atomic layer deposition of hydrogen on platinum in an ALD process, exposing platinum to different hydrogen flow rates and taking a sum frequency generation measurement of the surface of platinum. Curve 510 shows the set of intensities of the SFG (measured in s ⁻¹ ) versus the set of wavenumbers (measured in cm ⁻¹ ) after exposure of platinum to the highest flow rate of hydrogen. After exposure of platinum to the highest flow rate of hydrogen, SFG spectroscopy shows a relatively high intensity (ie, greater than 1.1) of the 2020 cm ⁻¹ wavenumber, as shown at point 512 . After exposure of the platinum to a lower flow rate of hydrogen, SFG spectroscopy shows a lower intensity (ie, approximately 0.95) of the 2020 cm ⁻¹ wavenumber, as shown at point 514 . After each of the third, fourth, fifth, and sixth exposures of platinum to successively lower flow rates of hydrogen, SFG spectroscopy, as shown at points 516 , 518 , and 520 , 2020 cm ^-1 wavenumber exhibits even lower intensities (ie, less than 0.90). After exposure of platinum to the lowest flow rate of hydrogen, SFG spectroscopy shows the lowest intensity (ie, 0.38) of the 2020 cm ⁻¹ wavenumber, as shown at point 522 .

According to aspects of the present disclosure, the technique of SFG spectroscopy is very specific to surfaces and interfaces, and thus analysis of data from SFG spectroscopy typically involves the subtraction of background signals from the measured signal. don't ask for

6 illustrates a configuration (eg, ACS Catalysis, 2014, 4 (6), pp. 1964) to monitor a substrate 670 (eg, platinum) during ALD processing, in accordance with aspects of the present disclosure; -1971) is a schematic diagram of an exemplary SFG spectroscopy system 600 . In the exemplary ALD processing chamber 680 , hydrogen flows into the chamber and over the substrate at location 682 , which catalyzes the hydrogen dissociation and forms a layer on the substrate. A mass spectrometer (MS) monitors the gases leaving the chamber to collect data on the amount of hydrogen deposited on the substrate. Heating rods 684 and piston 686 control the temperature and pressure within the ALD chamber. In the exemplary SFG spectroscopy system, the tunable laser system (ie, one or more electromagnetic radiation emitter(s)) 602 is in the infrared range (ie, 1 to 9 micrometers, such as 4 to 7 micrometers or 5 to 6 micrometers). micrometers), and a wavelength in the visible range (ie, 520-900 nanometers, such as 600-900 nanometers, 750-850 nanometers, or 800 nanometers). A second pulse of laser light 606 with The first pulse of laser light then passes through various filters 608 that fine tune the frequency of the first pulse to the desired frequency. The first pulse is then aimed by the lens 610 to enter the first view port 652 into the processing chamber. The second pulse is passed through filters 616 to fine tune the frequency of the second pulse. The lens 620 aims a second pulse to pass through the first view port 652 into the processing chamber. The first pulse and the second pulse may also be aimed through the prism 612 to illuminate the substrate 670 . The first and second pulses interact to produce a second harmonic pulse 630 as they illuminate the substrate. A second harmonic pulse may be aimed through the prism 612 to exit the processing chamber through the second view port 654 . Lens 640 and filter 642 may collimate the second harmonic pulse and filter out the reflections of the first and second pulses, such that a photomultiplier tube (PMT) 632 may displace the second harmonic pulse. Harmonic pulses can be collected. The PMT supplies information about the second harmonic pulse to the boxcar integrator 634 . Finally, the boxcar integrator feeds a signal to the computer 636 for interpretation.

According to aspects of the present disclosure, the first view port 652 and the second view port 654 may be formed of magnesium fluoride (MgF ₂ ) or calcium fluoride (CaF ₂ ) because: This is because the materials allow passage of both a first pulse having a wavelength in the infrared range and a second pulse having a wavelength in the visible range.

7 is a schematic diagram of an exemplary substrate processing blade 700 in accordance with aspects of the present disclosure. An exemplary substrate processing blade may include a substrate support blade 702 and an instrument support arm 704 . The instrument support arm may support a laser source 706 (eg, a fiber optic cable that carries laser light from one or more electromagnetic radiation emitters, lasers, or other laser light sources, such as remote lasers) and a spectrometer 708 . As illustrated in FIG. 6 , the laser source may deliver two pulses of laser light 710 , 712 having different wavelengths. As shown in FIG. 6 , the laser source may include one or more mirrors, filters, etalons, and lenses to direct laser light pulses to a substrate on a substrate processing blade. The spectrometer also includes one or more apertures, filters, lenses, and polarizers to block reflections 720 and 722 of the first and second pulses and also to aim a second harmonic pulse 724 to a detector in the spectrometer. can do.

According to aspects of the present disclosure, the instrument support arm 704 and the substrate processing blade 702 can move together into a processing chamber (eg, the processing chamber 100 shown in FIG. 1 ). Additionally or alternatively, the instrument support arm may move (eg, rotate apart) independently of the substrate processing blade as it enters the processing chamber.

In aspects of the present disclosure, instruments on the instrument support arm 704 , such as a laser source 706 and/or a spectrometer 708 , can be configured such that the substrate processing blade moves into a transfer chamber (eg, the transfer chamber shown in FIG. 2 ). Monitoring of the substrate supported by the substrate processing blade may be performed while within 206 ), allowing monitoring and/or inspection of the substrate without requiring a vacuum break in the processing system.

According to aspects of the present disclosure, the spectrometer may be a complementary metal oxide semiconductor (CMOS) spectrometer or a photonic crystal fiber (PCF) based spectrometer.

To provide a better understanding of the foregoing discussion, the above non-limiting examples have been provided. Examples may relate to specific embodiments, but the examples should not be construed as limiting the disclosure in any particular respect.

While the foregoing relates to embodiments of the present disclosure, other and additional embodiments of the disclosure may be devised without departing from the basic scope of the disclosure, the scope of which is set forth in the following claims. is determined by

Claims (15)

delete delete delete delete delete delete A system for processing a substrate comprising:
a processing chamber having a first slit valve opening and a second slit valve opening, wherein the first slit valve opening is configured to allow passage of a substrate through the first slit valve opening, and wherein the second slit valve opening comprises the second configured to allow passage of the substrate through a slit valve opening;
a first slit valve operable to open and close the first slit valve opening of the processing chamber, the first slit valve operable to create a first hermetic seal when closed;
a second slit valve operable to open and close the second slit valve opening of the processing chamber, the second slit valve operable to create a second hermetic seal when closed;
a load-lock having a transfer slit valve opening aligned with the second slit valve opening of the processing chamber, a load-lock port, and a substrate support; and
a mechanical arm having an encased probe;
the mechanical arm is operable to access the interior of the load-lock through the load-lock port;
the mechanical arm is operable to move an instrument within the embedded probe proximate the substrate on the substrate support;
wherein the embedded probe has an emitter operable to emit electromagnetic radiation for illuminating the substrate;
wherein the embedded probe has a detector operable to detect electromagnetic radiation scattered from the substrate. 8. The method of claim 7,
a substrate processing robot having a substrate processing blade;
the substrate processing blade includes an instrument support arm;
the instrument support arm is connected to the substrate processing robot;
and the instruments on the instrument support arm are operable to monitor the substrate on the substrate processing blade. 8. The method of claim 7,
wherein the emitter comprises a first laser source operable to generate a first pulse of laser light having a first wavelength and a second laser source operable to generate a second pulse of laser light having a second wavelength; A system for processing substrates. 10. The method of claim 9,
The first wavelength is 1 micrometer to 4 micrometers,
wherein the second wavelength is between 750 nanometers and 850 nanometers. 10. The method of claim 9,
wherein the detector is operable to measure the intensity of a sum frequency generation (SFG) pulse caused by interaction between the first pulse, the second pulse, and the substrate on the substrate support. . An apparatus for measuring a substrate in a processing system, comprising:
a mechanical arm operable to access the interior of a load-lock of the processing system;
an embedded probe on the mechanical arm;
an emitter within the embedded probe and operable to emit electromagnetic radiation for illuminating the substrate; and
a detector within the embedded probe and operable to detect electromagnetic radiation scattered from the substrate, wherein the mechanical arm is operable to move at least one of the emitter or the detector proximate the substrate. A device for measuring substrates. 13. The method of claim 12,
wherein the emitter comprises a first laser source operable to generate a first pulse of laser light having a first wavelength and a second laser source operable to generate a second pulse of laser light having a second wavelength; A device for measuring substrates in a processing system. 14. The method of claim 13,
The first wavelength is 1 micrometer to 4 micrometers,
and the second wavelength is between 750 nanometers and 850 nanometers. 14. The method of claim 13,
wherein the detector is operable to measure the intensity of a sum frequency generation (SFG) pulse caused by interaction between the first pulse, the second pulse, and the substrate.

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