JP2006138837A - Multifunction x-ray analysis system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus capable of easily performing measurement of small angle scattering, X-ray diffraction, or reflectance by use of one apparatus. <P>SOLUTION: The apparatus for analysis of a sample includes a radiation source, which is adapted to direct a converging beam of X-rays toward a surface of the sample and to direct a second collimated beam of the X-rays toward the surface of the sample. A motion assembly moves the radiation source between a first source position, in which the X-rays are directed toward the surface of the sample at a grazing angle, and a second source position, in which the X-rays are directed toward the surface in a vicinity of a Bragg angle of the sample. A detector assembly senses the X-rays scattered from the sample as a function of angle while the radiation source is in either of the first and second source configurations and in either of the first and second source positions. A signal processing part receives and processes output signals from the detector assembly so as to determine a characteristic of the sample. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates generally to analytical instruments, and specifically to instruments and methods for material analysis using X-rays.

  X-ray reflectometry (XRR) is a well-known technique for measuring the film thickness, density and surface quality of a thin film layer deposited on a substrate. Such a reflectometer normally operates by irradiating the sample with X-rays at a grazing angle near the total reflection angle of the sample material, that is, at a small angle with respect to the sample surface. By measuring the X-ray intensity reflected from the sample as a function of angle, an interference fringe pattern is obtained and analyzed to determine the characteristics of the film layer involved in creating the interference fringe pattern. Exemplary XRR systems and methods are described in US Pat. Nos. 5,619,548, 5,923,720, 6,512,814, 6,639,968, and 6,771. , 735, the disclosures of which are incorporated herein by reference.

X-ray small angle scattering (SAXS) is another method for evaluating surface layer properties. This is described, for example, in Parrill et al., “GISAXS-Granching Incidence Small Angle X-ray Scattering” (Journal de Physique IV 3, December 1993, pages 411-417). Which is incorporated herein by reference. In this method, the incident X-ray beam is totally reflected at the surface. Evanescent waves in the surface region are scattered by the microstructure in the region. Information on the structure can be obtained by measuring the scattered evanescent wave. For example, by using SAXS in this way, the characteristics of vacancies in the surface layer of a low dielectric constant dielectric formed on a silicon wafer can be measured.
US Pat. No. 5,619,548 US Pat. No. 5,923,720 US Pat. No. 6,512,814 US Pat. No. 6,639,968 US Pat. No. 6,771,735 US Pat. No. 6,895,075 US Pat. No. 6,381,303 US Pat. No. 6,389,102 US Patent Application No. 11 / 000,044 US Patent Publication No. 2004 / 0109531A1 US Patent Publication No. 2004/0131151 A1 US Pat. No. 6,643,354 US patent application Ser. No. 10 / 902,177 US Patent Publication No. 2001 / 0043668A1 Parrill et al., “GISAXS-Granching Incidence Small X-ray Scattering” (Journal de Physiique IV 3, December 1993, 411-417). Bowen et al., “X-Ray metrology by Diffraction and Reflectivity” (Characterization and Metrology for ULSI Technology, 2000 International Technology, 2000 International). Goorsky et al., “Grazing Incidence In-plane Diffusion Measurement of In-plane Moisture Micro-Train Refocus”. 37: 7 (2002), pages 645-653) Kozaczek et al., “X-ray Diffraction Metrology for 200 mm Process Qualification and Stableness Assessment, Canada 10th Month, Advanced Metallology, 10th Annual Metallurgy, 10th Annual Metallization. ~ 11 days)

  US Pat. No. 6,895,075, the disclosure of which is incorporated herein by reference, describes a method and system for measuring samples using a combination of XRR and SAXS. Although XRR and SAXS are complementary in terms of the information they obtain, there are inherent difficulties in making both measurements using a single system. From the viewpoint of irradiating the sample, it is advantageous to use a parallel beam in order to perform precise measurement with SAXS. On the other hand, in XRR, it may be advantageous to use a convergent beam having a large convergence angle so that reflectance measurements in a plurality of angular ranges can be performed simultaneously. In the embodiment disclosed in US Pat. No. 6,895,075, the x-ray inspection apparatus includes a radiation source configured to irradiate a narrow area of the sample surface. X-ray optics adjust the angular width and height of the radiation beam as appropriate for XRR or SAXS.

With respect to detection, SAXS typically observes scattering within the surface of a sample as a function of orientation, while XRR is based on measuring reflected X-rays perpendicular to the surface as a function of elevation. In the embodiment described in US Pat. No. 6,895,075, the detection assembly comprises an array of detection elements arranged to receive radiation reflected or scattered from the illuminated area. The array has two operational configurations, one of which the elements of the array decompose the emitted light along an axis perpendicular to the sample plane, and the other, the elements are on an axis parallel to the plane. Along the way, decompose the emitted light. Depending on the type of measurement to be performed, an appropriate configuration is selected mechanically or electronically.

X-ray diffraction (XRD) is a well-known technique for observing the crystal structure of a substance. In XRD, a sample is irradiated with a monochromatic X-ray beam, and the position and intensity of a diffraction peak are measured. The scattering angle and scattered light intensity characteristic of the sample to be observed are determined by the lattice plane of the sample and the atoms occupying the plane. A diffraction peak is observed when an X-ray beam is incident on the grating plane at an angle θ that satisfies the Bragg condition nλ = 2d sin θ (n is the scattering order) for a given wavelength λ and grating plane spacing d. The angle θ that satisfies the Bragg condition is known as the Bragg angle. Lattice distortion due to stress, solid solution, or other effects appears in the XRD spectrum as a visible change.

XRD has been used in particular to measure the properties of crystalline layers formed on semiconductor wafers. For example, Bowen et al., “X-Ray metrology by Diffraction and Reflectivity,” and “Characterization and Metrology for Biotechnology, 2000 International Technology, 2000 International Technology, 2000 International Technology.” A method for measuring germanium concentration in a SiGe structure using XRD is described and is incorporated herein by reference.

XRD may also be used to observe the structure of the sample surface with incidence at a grazing angle. For example, Goorsky et al., “Grazing Incidence In-plane Diffraction Measurement of In-plane Mosaic MicroRefocus (X-ray)”. and Technology, 37: 7 (2002), pages 645-653) describe the use of grazing incidence XRD to analyze the epitaxial layer structure of a semiconductor wafer, which is incorporated herein by reference. . The authors apply a method to measure the in-plane lattice parameters and lattice orientation of ultra-thin surfaces and buried semiconductor layers.

In the context of this patent application and claims, the terms “scattering” and “scattering” are used to refer to any process in which X-rays are emitted from a sample by irradiating the sample with X-rays. . Thus, in this context, “scattering” encompasses phenomena in XRR, XRD and SAXS, as well as other scattering phenomena known in the art such as X-ray fluorescence (XRF). On the other hand, the specific term “X-ray small angle scattering”, abbreviated as SAXS, refers to a unique phenomenon called grazing angle scattering on the sample plane as described above.

The aforementioned US patent application Ser. No. 10 / 946,426 describes a sample analysis system based on high speed XRR and XRD. The radiation source directs an X-ray focused beam to the surface of a sample such as a semiconductor wafer. The detection element array senses X-rays scattered from the sample simultaneously as a function of the elevation angle over a plurality of elevation angle ranges. The system has XRR and XRD configurations. In the XRR configuration, the radiation source and detector element array are arranged such that the array senses x-rays reflected at a grazing angle from the sample surface. In the XRD configuration, the radiation source and detector element array are arranged such that the array senses X-rays diffracted from the sample surface near the Bragg angle. An operating assembly may be provided to shift the radiation source and detector element array between XRR and XRD configurations.

Some embodiments of the present invention employ a complex system that goes one step further, thus providing SAXS measurement capability. As such, the x-ray optical element associated with the radiation source can be configured to generate either a focused beam or a collimated beam. The focused beam is used for XRR and high resolution XRD measurements, and the detector element array is positioned to resolve scattered radiation along an axis perpendicular to the sample plane. The collimated beam can be used to perform high speed, low resolution XRD as well as SAXS measurements. For SAXS, the detector element array is arranged to resolve radiated light scattered along an axis parallel to the sample plane.

Alternatively or in addition, the system can be configured such that grazing angle XRD measurements can also be performed.

Thus, a single x-ray source can be used to perform different (and complementary) x-ray scatter measurements for a given sample. Such composite performance is particularly useful for thin film X-ray metrology to determine thin film layer density, film thickness, crystal structure, porosity, and other properties. Alternatively or in addition, the principles of the present invention may be applied to other fields of X-ray analysis and metrology. As yet another method, aspects of the embodiments described below may be used in a system specialized for one type of scatter measurement, such as SAXS, that does not necessarily provide multifunctional performance.

Thus, according to one embodiment of the present invention,
An illumination source configured to direct a first X-ray focused beam to the sample surface and a second X-ray parallel beam to the sample surface;
The radiation source is between a first light source position where X-rays are directed from the radiation source to the sample surface at a grazing angle and a second light source position where X-rays are directed from the radiation source to the sample surface in the vicinity of the Bragg angle of the sample. An actuating assembly that operates to move in
When the radiation source is in either of the first and second light source configurations, and in either of the first and second light source positions, the scattered X-ray is sensed as a function of angle, as detected from the sample. A sensing element assembly configured to generate an output signal in response to
A sample analyzer is provided comprising a signal processor coupled to receive and process the output signal and to determine the characteristics of the sample.

  In the disclosed embodiment, the radiation source includes an X-ray tube that functions to emit X-rays, a first mirror configured to receive and collect X-rays into a focused beam, and X-rays And a second mirror configured to receive and collect the line into a collimated beam. In general, the first and second mirrors include a double curved structure.

  In some embodiments, the motion assembly includes a first detection element elevation angle at which the detection element assembly senses X-rays scattered from the sample at a grazing angle, and an X-ray scattered from the sample by the detection element assembly near a Bragg angle. It functions to move the sensing element assembly between a sensing second sensing element elevation angle. The motion assembly also diffracts the detector element assembly at a first detector element elevation angle, a first azimuth angle at which the detector element assembly senses small angle scattering of X-rays, and the detector element assembly diffracts from the in-plane structure of the sample surface. It may function to move between a second larger azimuth angle that senses the emitted X-rays.

  In one disclosed embodiment, the detector element assembly includes a first detector element configuration for resolving scattered X-rays along a first axis perpendicular to the sample surface, and a first X-ray element parallel to the sample. A detector element array having a second detector element configuration that resolves along two axes. In general, the signal processing unit processes the output signal from the detection element assembly in the first detection element configuration to determine the reflectance of the surface as a function of the elevation angle relative to the surface, and the detection in the second detection element configuration The output signal from the element assembly is processed to determine the scattering properties of the surface as a function of the azimuth angle in the sample plane.

  In some embodiments, the signal processor processes the output signal from the detector element assembly when the radiation source emits the first beam and is at the first light source position to provide a surface x-ray reflection. A rate (XRR) spectrum is acquired, and when the radiation source emits a second beam and is in the first light source position, the output signal from the detector element assembly is processed to produce a small angle X-ray scattering ( Acquiring at least one of a SAXS) spectrum and a small angle X-ray diffraction (XRD) spectrum, and processing the output signal from the detector element assembly when the radiation source is at the second light source position to obtain a high angle of the surface Configured to acquire an XRD spectrum.

  In one embodiment, the signal processor obtains a high resolution XRD spectrum when the radiation source is at the second light source position and emits the first beam, and the radiation source is at the second light source position. It is configured to acquire a low resolution XRD spectrum when emitting the second beam. In general, the motion sensor places the detector assembly at a first distance from the sample surface to obtain a high resolution XRD spectrum and moves the detector assembly from the sample surface to obtain a low resolution XRD spectrum. It arrange | positions so that it may arrange | position to the 2nd distance smaller than 1 distance.

  Alternatively or additionally, when the sample includes at least one surface layer, the signal processor analyzes two or more of the XRR, SAXS and XRD spectra to determine the characteristics of the at least one surface layer. It may be configured to determine. In general, properties include film thickness, density, surface quality, porosity, and crystal structure.

  In one disclosed embodiment, the apparatus is positioned parallel to the sample surface and proximate to the selected region to define a gap between the surface and the knife edge and block a portion of the beam that does not pass through the gap. Includes knife edge. The apparatus may also include a beam blocker that blocks X-rays that travel through the air gap and further propagate along the beam axis without blocking X-rays scattered within the angular range of interest.

Also, according to one embodiment of the present invention,
An irradiation source that functions to direct a parallel X-ray beam toward a selected region of the sample at a grazing angle along the beam axis and to scatter a portion of the X-ray from the entire azimuthal range;
A knife edge, positioned parallel to the sample surface and close to the selected area, defining a gap between the surface and the knife edge and blocking a portion of the beam that does not pass through the gap;
A beam blocker configured to block X-rays that pass through the air gap and further propagate along the beam axis without blocking X-rays scattered in at least a portion of the azimuthal range;
A sensing element assembly configured to sense scattered x-rays as a function of azimuth and to generate an output signal in response to the scattered x-rays;
A sample analyzer is provided that includes a signal processor coupled to receive and process the output signal and to determine sample characteristics.

  In the disclosed embodiment, the apparatus is at least one perpendicular to the sample surface and disposed between the radiation source and the knife edge to pass at least a portion of the parallel beam while blocking scattered x-rays. Includes a slit. The at least one slit may include a first slit disposed proximate to the radiation and a second slit disposed proximate to the knife edge.

  Alternatively or in addition, the sensing element assembly includes an array of sensing elements having an array length and an exhaustable housing having a front surface and a back surface that are spaced a distance equal to at least the array length. Is disposed on the back of the housing, and the housing includes a window in front of the housing and is configured such that the emitted light passes through it and strikes the array.

Furthermore, according to one embodiment of the present invention,
An irradiation source that functions to direct an X-ray beam to a selected region of the sample and to scatter a portion of the X-ray from the region;
A knife that includes a cylinder of X-ray absorbing material that is positioned parallel to the sample surface and in close proximity to the selected region to define a gap between the surface and the cylinder and block portions of the beam that do not pass through the gap. Edge,
A sensing element assembly configured to sense scattered x-rays as a function of angle and to generate an output signal in response to the scattered x-rays;
A sample analyzer is provided that includes a signal processor coupled to receive and process the output signal and to determine sample characteristics.

  In the disclosed embodiment, the cylinder of X-ray absorbing material includes a metal wire.

Furthermore, according to one embodiment of the present invention,
A mounting assembly that supports the sample and adjusts the orientation during the analysis,
An irradiation source that functions to direct an X-ray parallel beam to a selected region on the sample surface and to scatter a portion of the X-ray from the entire azimuthal range;
A sensing element assembly configured to sense scattered X-rays as a function of azimuth and to generate an output signal in response to the scattered X-rays;
Capability to accept tilt map showing characteristic surface tilt angle, determine tilt angle of selected area based on tilt map, and direct mounting assembly in response to estimated tilt angle to adjust sample orientation There is provided a sample analysis apparatus including a signal processing unit that includes a signal processing unit that determines the characteristics of the sample by processing the output signal after adjusting the orientation.

  Typically, the illumination source functions to direct a focused beam of x-rays to each of a plurality of locations on the sample, and the detector element assembly functions to sense x-rays reflected from the surface as a function of elevation relative to the surface; The signal processing unit functions to measure an X-ray reflectivity (XRR) spectrum at each position in response to the reflected X-ray, and to determine an inclination angle at each position based on the XRR spectrum.

Still further, according to one embodiment of the present invention,
Operating an irradiation source configured to direct a first X-ray focused beam to the sample surface and a second X-ray parallel beam to the sample surface;
The radiation source is between a first light source position where X-rays are directed from the radiation source to the sample surface at a grazing angle and a second light source position where X-rays are directed from the radiation source to the sample surface in the vicinity of the Bragg angle of the sample. Move it with
X-rays scattered from the sample are sensed as a function of angle to determine sample characteristics when the radiation source is in both the first and second light source configurations and in both the first and second light source positions. A sample analysis method is provided.

Furthermore, according to one embodiment of the present invention,
Directing an X-ray parallel beam at a grazing angle along the beam axis to a selected area of the sample such that a portion of the X-ray scatters from the entire azimuthal range;
A knife edge is placed parallel to the sample surface and close to the selected area to define a gap between the surface and the knife edge, blocking the portion of the beam that does not pass through the gap,
A beam blocking part is arranged to block X-rays that pass through the air gap and propagate along the beam axis without blocking X-rays scattered in at least a part of the azimuth angle range;
A sample analysis method is provided that includes sensing scattered X-rays as a function of azimuth to determine sample characteristics.

Furthermore, according to one embodiment of the present invention,
Direct the x-ray beam to a selected area of the sample so that part of the x-ray is scattered from the area;
A cylinder of X-ray absorbing material is placed parallel to the sample surface and in close proximity to the selected area to define a gap between the surface and the cylinder, blocking a portion of the beam that does not pass through the gap;
A sample analysis method is provided that includes sensing scattered X-rays as a function of angle to determine sample characteristics.

Furthermore, according to one embodiment of the present invention,
Generate a sample tilt map,
Directing an X-ray parallel beam at a grazing angle along the beam axis to a selected area of the sample such that a portion of the X-ray scatters from the entire azimuthal range;
Based on the tilt map, determine the tilt angle of the selected area,
Adjust the sample orientation to compensate the tilt angle,
After adjusting the orientation, a sample analysis method is provided that includes sensing scattered X-rays as a function of azimuth to determine sample characteristics. The present invention will be more fully understood when the following detailed description of the embodiments is read in conjunction with the drawings.

  FIG. 1 is a schematic side view of a system 20 for measuring and analyzing X-ray scattering from a sample 22 in accordance with one embodiment of the present invention. The system 20 can perform X-ray reflectometry (XRR), X-ray small angle scattering (SAXS) and X-ray diffraction (XRD) in both high and low resolution modes. The sample 22 is mounted on a mounting assembly, such as an operating stage 24, that allows the position and orientation of the sample to be precisely adjusted. The X-ray source 26 irradiates a small area 50 of the sample 22. X-rays scattered from the sample are collected by the detection element assembly 32.

  The light source operation assembly 28 shifts the illumination source 26 between an upper light source position and a lower light source position for different types of measurements, as described below. Similarly, the sensing element operation assembly 34 moves the sensing element assembly 32 between an upper sensing element position and a lower sensing element position. As described in more detail below, the lower position of the light source assembly and detector assembly is typically used for SRR and SAXS, and optionally additionally for small angle XRD (GIXRD), while the upper position is used for high angle XRD. The In GIXRD, the detection element assembly is also shifted laterally as described below and shown in FIG.

  In the example shown in FIG. 1, the motion assembly includes curved trajectories 30 and 36 along which the light source assembly 26 and the detector element assembly 32 each translate while maintaining a constant distance from the region 50. Alternatively or in addition, the sensing element operating assembly 34 may be capable of changing the distance between the sensing element assembly and the region 50, thereby changing the effective capture angle and angular resolution of the detection. . The light source motion assembly may also be capable of this type of axial motion (ie, motion along the axis of the x-ray beam in addition to the vertical lateral motion provided by the trajectories 30 and 36). As a further alternative or in addition, the sensing element operating assembly may rotate the sensing element assembly and / or shift the sensing element assembly in a horizontal lateral direction as described below. Also good.

  Curved trajectories 30 and 36 are only examples of motion assemblies that may be used within system 20, and other suitable types of motion assemblies used for such purposes will be apparent to those skilled in the art. . For example, the x-ray source and detector element assembly may be mounted on separate plates, tilted, lifted or pulled down and placed in the position shown in FIG. All motion assemblies of this type are considered to be within the scope of the present invention. In this patent application and in the claims, where the term “motion assembly” is used without further detailed description, it refers to either or both of the light source motion assembly and the detector element motion assembly, depending on the context in which the term is used. Should be interpreted.

  Alternatively, multiple X-ray sources and / or multiple detector element assemblies may be used for XRR and XRD measurements. In this case, no motion assembly may be required. As a further alternative, a single x-ray tube may be shifted between a lower position and an upper position, each position having its own fixed optical element.

The x-ray source 26 may be configured to generate either a convergent x-ray beam or a collimated beam, as will be described in more detail below with reference to FIG. FIG. 1 shows the configuration of a focused beam used for XRR and high-resolution XRD measurements, and FIG. 2 shows SAXS, GIXRD, and conventional XRD measurements (here, high-resolution XRD mode using parallel beams) The configuration of both convergent and collimated beams used for distinction, referred to as “low resolution” XRD) is shown. In the context of this patent application and claims, a beam is considered “parallel” when its opening (full width at half maximum−FWHM) is less than 0.5 °. This degree of parallelism is sufficient for the type of SAXS and low resolution XRD measurements formed by the system 20, but generally better measurements if the parallelism is better (eg, 0.3 ° opening). Results are obtained.
The following table outlines the selective configuration of the system.

  Referring now to the details of the system 20, the x-ray source 26 typically includes an x-ray tube 38 mounted on the light source operation assembly 40. Since the tube 38 generally has a narrow radiation area, it can be precisely focused on the surface of the sample 22. For example, tube 28 comprises an XTF 5011 x-ray tube manufactured by Oxford Instruments, Scott Valley, CA. The standard x-ray energy for reflectance and scatter measurements in system 20 is about 8.05 keV (CuKal). Alternatively, other energy such as 5.4 keV (CrKal) may be used.

  In the XRR configuration shown in FIG. 1, the condensing optical element 42 condenses the beam emitted from the tube 38 into a convergent beam 44 that converges to the focal point of the region 50. In general, the optical element 42 comprises a double curved crystal, which also monochromates the beam 44. Optical elements that may be used in system 20 for this purpose are described, for example, in US Pat. No. 6,381,303, the disclosure of which is incorporated herein by reference. The optical element may comprise a curved crystal monochromator, such as a Double-Bent Focusing Crystal Optic manufactured by XOS Inc. (XOS Inc., Albany, NY). Other suitable optical elements are described in the aforementioned US Pat. Nos. 5,619,548 and 5,923,720. Due to the double curved focus crystal, the beam 44 converges in both the horizontal and vertical directions and is almost focused at a point in the region 50. Alternatively, the beam 34 may be collected using a cylindrical optical element, and the beam may be converged to one line on the sample surface. Further possible optical element configurations will be apparent to those skilled in the art.

For XRR measurements, the focused beam 44 typically impinges on the region 50 at a grazing angle over the entire incident angle range of about 0 ° to 4.5 °, although larger or smaller angles are possible. In this configuration, the detector element assembly 32 collects the reflected X-ray divergent beam 52 as a function of elevation angle (Φ) from about 0 ° to at least 2 °, typically about 3 °, over the entire vertical angular range. . This range encompasses both above and below the critical angle of the sample for total external reflection Φ _c . (For clarity of illustration, the angular range shown in the figure is exaggerated, and the rise of the light source 26 and detector element assembly 38 above the plane of the sample 22 in the XRR configuration is also exaggerated. In order to simplify and clarify the accompanying description, the sample plane is arbitrarily an XY plane, where the Y axis is parallel to the axis of the X-ray beam projected on the sample surface, and the Z axis is the sample plane. It is perpendicular to the vertical direction.)

  A dynamic knife edge 48 and shutter 46 may be used to limit the angular range of the x-ray incident beam 44 in the vertical direction (ie, perpendicular to the sample 22 plane). The use of these beam limiting optics in an XRR configuration is described in the aforementioned US Pat. No. 6,512,814. Knife edge 48 may also be used with beam blockers and beam limiting slits (shown in FIG. 4 but omitted in FIG. 1 for simplicity) to reduce background scatter in SAXS configurations. . The height of the knife edge and the shutter relative to the sample surface can be adjusted according to the type of measurement to be performed and the range of measurement angles to be measured.

  The detection element assembly 32 includes a detection element array 54 such as a CCD array. For simplicity of illustration, only one row of detector elements having a relatively small number of detector elements is shown in the figure, but the array 54 is typically arranged in a linear or matrix (two-dimensional) array. More elements. Further aspects of detector element assembly 32 and array 54 are described below with reference to FIG.

  The signal processor 56 receives and analyzes the output from the detector element assembly 32 to determine the distribution 58 of the x-ray photon flux scattered from the sample 22 as a function of angle for a given energy or energy range. To do. Typically, the sample 22 has one or more thin surface layers, such as thin films, in the region 50, and the distribution 58 as a function of angle can be caused by interference, diffraction and / or other scattering effects due to the surface layer and layer interface. A structure showing the characteristics of The processing unit 56 analyzes the characteristics of the angular distribution and describes the characteristics of one or more surface layers of the sample, such as film thickness, density, porosity, composition, and surface quality of the layers, as described in the above-mentioned patents and patent applications. Determine using analytical methods. The processing unit 56 (or other computer) may function as a system control unit that sets and adjusts the position and configuration of other system components.

  The high resolution XRD configuration of the system 20 is particularly useful for evaluating the physical properties of the single crystal film on the sample 22. In this configuration, both the light source 26 and the detector element assembly 32 are shifted to a relatively high angle near the Bragg angle of the sample 22 as shown in the table above. The light source 26 irradiates the convergent beam 60 in the vicinity of the Bragg angle of the region 50, and the detection element assembly 32 receives the divergent beam 62 over the entire angular range near the Bragg angle. In this example, the grating plane that forms the diffraction pattern is assumed to be substantially parallel to the surface of the sample 22, so that the incident and exit angles for the surface defined by the beams 60 and 62 are both equal to the Bragg angle. This assumption is often true for semiconductor substrates, such as silicon wafers, and single crystal thin film layers grown on those substrates. Alternatively, the light source 26 and the detector element assembly 32 may be arranged at different incident and exit angles to measure diffraction from a grating plane that is not parallel to the sample 22 surface.

  FIG. 2 shows a schematic top view of the system 20 according to one embodiment of the present invention. This figure shows that X-rays from the tube 38 impinge on both the condensing optical element 42 and the collimating optical element 72 (omitted in FIG. 1 for clarity of illustration). The light source mounting assembly 40 positions the tube 38 so that the beam from the tube impinges on the optical element 42 at an appropriate angle and the beam 44 converges on the region 50. The beam from the x-ray tube 38 also strikes the collimating optical element 72 at an appropriate angle, producing a convergent beam 74 that also strikes the region 50. The optical element 72 may comprise, for example, a double-curved mirror with a multi-functional coating that reflects 8 keV radiation and produces a beam with an openness <0.3 ° and a spot size <100 μm. This type of optical element is available from many manufacturers, such as Applied X-ray Optics (AXO, Dresden, Germany). This optical element also monochromates the X-ray beam. In the concentrating and collimating optical elements described above, the X-ray tube and optical element typically have X-rays from the tube at an angle of about 14 ° to the optical element 42 and at an angle of about 1 ° to the optical element 72. Arranged to collide.

  By arranging the X-ray tube 38 and the optical elements 42 and 72, the directions of the convergent beam 44 and the parallel beam 74 are shifted, that is, the beam axes are not collinear. The beam generated by the x-ray tube 38 and the apertures of the optical elements 42 and 72 are sufficiently wide so that the beam strikes both the optical elements 42 and 72 without moving the tube or optical element. Also good. Alternatively, if a narrower beam and / or aperture is used, the x-ray tube may translate vertically between the XRR and SAXS positions. In either case, typically one of beams 44 and 74 is used for the measurement at a given time. Therefore, the movable light source beam blocking unit 75 may be arranged to block a part of the beam from the X-ray tube so that only one of the beams 44 and 74 collides with the sample 22. (Alternatively, depending on the application, two beams may be generated at the same time.) Due to this misalignment, the divergent beam 52 generated in the XRR mode is different from the scattered beam 70 generated in the SAXS mode. Shifts in the X direction. To compensate for this deviation, the sensing element assembly 32 may be shifted in the X direction depending on the operating mode of the system 20. Alternatively, the detector element assembly may comprise two detector element arrays arranged and oriented to capture beams 52 and 70, respectively.

  System 20 is well suited for low resolution XRD measurements when the light source and detector element assembly are in a high angle position and the light source assembly is in a parallel beam configuration. This type of measurement is particularly useful for evaluating the phase and texture of a polycrystalline structure, such as a polycrystal in a metal film on a semiconductor wafer. Since the orientation of such crystals is not controlled, the created XRD pattern is characterized as Debye ring. This phenomenon is described, for example, by Kozaczek et al., "X-ray Diffraction Metrology for 200 mm Process Quality and Stable Assessment Assessment," , Oct. 8-11, 2001), which is incorporated herein by reference.

  In this case, the angle range in which the XRD pattern extends is usually about 10 to 20 °. In order to cover this range, it is desirable to bring the detection element assembly 32 closer to the region 50 on the sample 22 so that the detection element array 54 covers a relatively wider range than in the high resolution configuration. Bringing the array closer to the sample also reduces the angular resolution, but a resolution of about 0.3 ° is sufficient to identify the polycrystalline phase. For this purpose, it is desirable to select the optical element 72 and adjust it so that the opening of the beam 74 does not exceed about 0.3 °.

  In the case of SAXS, the light source assembly 26 and the detection element assembly 32 are arranged at a lower position. Optionally, in the case of SAXS, the light source operation assembly 28 is manipulated to bring the light source assembly 26 slightly closer to the XY plane than in XRR so that the collimated beam 74 strikes the region 50 at a suitably low angle. To. Alternatively, the optical element 72 may be supported by the assembly 74 at a lower elevation than the optical element 42 so that the beam 74 is emitted from the assembly 26 along a lower beam axis than the beam 44. As will be described below, the orientation of the detector array 54 may be rotated for SAXS to collect and resolve scattered X-rays over a horizontal (azimuth-θ) angular range. Usually, the scattering spectrum is measured over a range of about 0-3 °. In order to improve the angular resolution of the SAXS, the detection element assembly 32 is usually held at a position relatively far from the region 50.

  In the case of GIXRD, the light source assembly 26 is arranged at substantially the same position as SAXS. However, the detector element assembly 32 is typically shifted laterally to a higher azimuth in the plane of the sample 22 by the detector element working assembly to capture the diffracted beam 75. The azimuth angle of the diffracted beam 75 with respect to the incident parallel beam 74 is determined by the Bragg angle of the in-plane structure on the sample surface involved in diffraction. The stage 24 (FIG. 1) may be configured to rotate the sample 22 in the XY plane so that the in-plane grating is aligned with the incident beam angle.

  3A and 3B are schematic front views of first and second operational configurations of detector element array 54, respectively, in accordance with one embodiment of the present invention. The first configuration shown in FIG. 3A is used for XRR and high angle XRD, and the second configuration shown in FIG. 3B is used for SAXS and GIXRD measurements. In these figures, the array 54 is shown as comprising a row of detector elements 76, which are Z-axis perpendicular to the sample 22 plane for XRR and high angle XRD, and samples for SAXS and GIXRD. It has an array axis that can be aligned to resolve incident light along one of two axes, the X axis parallel to the plane.

  The detection element 76 has a high aspect ratio, i.e., the width across the array axis is sufficiently larger than the length along the axis. Having a high aspect ratio is useful for improving the signal / noise ratio of the system 20 because the array 54 can collect x-ray photons over a relatively large area that increases in angle along the array axis. In the figure, the dimensions of element 76 are shown for illustrative purposes only, and the principles of the present invention may be applied to smaller or larger aspect ratio elements depending on the needs of the application and the ability of a suitable detection instrument. it can.

  The detection element array 54 may comprise either a linear array or a matrix array. In the case of a matrix array, the array may operate in a line-binning mode so that multiple detector elements in each column of the array function effectively as a single element with a high aspect ratio. In this case, array 54 physically comprises a two-dimensional matrix of detector elements, but functionally, the array takes the form of a row of detector elements, depending on the binning direction shown in FIGS. 4A and 4B. Alternatively, array 54 may comprise an array of PIN diodes with suitable readout circuitry, such as disclosed in US Pat. No. 6,389,102, the disclosure of which is incorporated herein by reference. A centralized processing electronic device may also be mentioned. Further details regarding the types of detector element arrays that can be used in the system 20 and adapting such arrays to XRR and SAXS are described in the aforementioned US Pat. No. 6,895,075.

The sensing element operating assembly 34 may be configured to mechanically rotate the sensing element assembly 32 between the orientations shown in FIGS. 3A and 3B. Alternatively, the sensing element assembly 32 itself may comprise an array operating device (not shown) that rotates the sensing element array 54 between the orientations shown in FIGS. 3A and 3B. In either case, the hardware rotates the array 90 ° between the vertical and parallel axes, depending on the type of measurement being performed. When the rotation point is close to the center of the array 54, it may be necessary to shift the array downward (closer to the plane of the sample 22) for SAXS measurement and upward for XRR. Alternatively, the rotation point may be fixed near the sample plane so that the vertical movement of the array is unnecessary. In general, in the SAXS configuration, the center of the array 54 is not near the axis of the incident beam 74. Since SAXS is typically symmetric about the incident beam axis, there is virtually no information lost and the array 54 is positioned to measure scattered radiation on one or both sides of the axis, increasing the angular range over which scattering is measured. Also good.

FIG. 4 is a schematic top view of system 20 according to one embodiment of the present invention, showing further details of the system configuration used for SAXS measurements. Since the SAXS signal is generally weak, the system 20 has developed a novel beam control to reduce background scattering that can cause a phenomenon where the pseudo X-rays impinge on the detector array 54 and interfere with the actual SAXS signal. Use optical elements. Specifically, as shown in this figure, the system includes an anti-scattering slit 80 and an anti-diffraction slit 82, and a knife edge 48 and a beam blocking unit 84. The purpose of each component will be described below.

The collimating optical element 72 has an output aperture shown as A in FIG. 4 from which X-rays may be diffracted and / or scattered toward the detector element array 54. (For example, in the case of the Xenocs mirror described above, the output aperture is 1.2 × 1.2 mm and the parallel output beam has an opening angle of about 0.3 °. The center of the aperture A is usually about The slit 82 is either for the radiated light scattered from the aperture to collide directly with the detection element array 54 or to collide with the sample 22 and reflect to the detection element array. Inhibits. In one exemplary embodiment, the slit 82 is about 0.4 mm wide and is positioned slightly above the sample 22 (usually less than 20 mm) in front of the knife edge 48. For best results, the lower portion of the slit 82 is located as close to the sample surface as possible, usually less than about 80 μm above the surface.

The slit 80 is usually disposed near the output opening of the optical element 72 and blocks X-rays diffracted from the opening. In one exemplary embodiment, the slit 80 is about 1 mm wide and is positioned less than about 10 mm from the opening A at about 160 mm from the focal region 50. The slit 80 typically extends both above and below the plane of the sample 22.

The knife edge 48 is also located slightly above the sample 22. The knife edge scatters from the aperture of the optical element 72 to block radiation that was not blocked by the slit 82, and from the slits 80 and 82 itself, or from atmospheric molecules between the optical element 72 and the region 50. Also cut off the emitted light. One possible configuration of the knife edge is described below with reference to FIG.

Appropriate parallel X-rays from optical element 72 pass through slits 80 and 82 and under knife edge 48 and impinge on region 50 on sample 22. Most of the incident X-rays are specularly reflected from the sample along the Y axis or pass directly under the knife edge 48 without reflection. These X-rays are then scattered by atmospheric molecules, resulting in impact on the detector array 54 at various angles. In order to reduce this undesirable scattering, the beam blocker 84 is positioned proximately behind the knife edge 48 and slightly above the sample 22. In one exemplary embodiment, the beam block is about 30 mm behind the knife edge and about 70 μm above the sample surface. The beam blocker is typically offset from the center as shown in the figure and positioned slightly across the beam axis (eg, about 250 μm) to block the direct or specularly reflected beam. As a result, the detection element array 54 receives almost the entire X-ray flux scattered from the region 50 horizontally separated from the Y-axis, and parasitic scattering from atmospheric molecules is almost blocked.

To further prevent parasitic scattering, the detector element assembly 32 may include a window 86 that is made of a suitable X-ray transmissive material, such as beryllium, away from the front of the detector element array 54. The window defines an evacuable housing 88 adjacent to the detector array 54. Typically, the distance from the array 54 to the window 86 is at least equal to the array length (measured along the array axis, ie, along the X direction of FIG. 3B), and is 2 to 3 times the array length or more. There may be. During operation, the housing is evacuated. Removing the atmosphere in the region immediately in front of the detector array and spacing the window away from the array is useful for further reducing parasitic X-ray scattering near the array. Further details of this type of window structure are described in the aforementioned US Pat. No. 6,512,814.

FIG. 5 is a schematic diagram of details of the knife edge 48, in accordance with one embodiment of the present invention. In this embodiment, the lower end of the knife adjacent to the surface of the sample 22 is made of a cylindrical X-ray absorbing material such as a metal wire 90. For example, in the case of an X-ray having a photon energy of 8 keV, the wire 90 includes a tantalum wire having a diameter of 200 μm. With this configuration, the lower end of the knife is very close to the sample surface and is placed at a position of about 3 μm on the surface without fear of damaging the sample.

The wire 90 can be precisely aligned with the sample, resulting in a small air gap on the surface, but this effective height is uniform over the entire angular range of interest, typically 0-4 °. It is. Unlike the case of using a knife with a flat edge, this alignment does not change when the wire is rotated around its axis. In general, the size of the air gap between the knife edge and the surface and its uniformity define the size and uniformity of the X-ray focus with respect to the surface. This type of small and uniform air gap is provided by the wire 90 to improve the spatial resolution and angular accuracy of scatter measurements performed in the system 20. Based on this embodiment, in the context of this patent application and claims, the term “knife edge” is any type that is placed near the sample surface to create this type of void and block X-rays outside the void. It will be understood that it refers to a straight edge (not necessarily sensitive).

FIG. 6 is a flow chart that schematically illustrates a method for performing SAXS measurements in system 20, in accordance with one embodiment of the present invention. The intensity of the SAXS signal is highly dependent on the average incident angle of the beam 74 (FIG. 4) with respect to the surface of the region 50. On the other hand, the incident angle is directly affected by the tilt of the sample. In standard SAXS applications, the beam 74 is caused to impinge on the sample surface at about 0.4 °. When the SAXS measurement is performed at a different position on the surface of the sample 22 and the inclination changes, for example, by ± 0.1 °, the incident angle changes by 0.3 to 0.5 ° over the entire surface. Due to this change in angle, the intensity of the SAXS spectrum measured at different positions appears to change greatly.

For example, in a typical application of the system 20, the sample 22 is a semiconductor wafer and is held in place on the stage 24 by being sucked through an inlet (not shown) on the stage surface. In such a situation, the wafer conforms to the shape of the stage and is deformed by the suction force. As a result, the local tilt angle of the wafer varies depending on the position of the wafer surface.

The method of FIG. 6 uses the XRR measurement function of the system 20 to solve the problems associated with sample tilt in SAXS. To this end, the system 20 operates in XRR mode to map the tilt of the sample 22 in the tilt mapping step 100. A representative method of slope mapping that may be used for this purpose is described in US patent application Ser. No. 11 / 000,044, assigned to the assignee of the present patent application, the disclosure of which is hereby incorporated by reference. Include in the book. In order to generate a map, the surface of the sample is divided into several areas, and the inclination of the surface of each area is measured to obtain an inclination value. (This map may be created using the SAXS sample itself, or a reference sample such as a bare silicon wafer may be used.) Any suitable method may be used to determine the surface tilt. May be. Representative methods for measuring tilt using XRR are disclosed in US Patent Publications US 2004/0109531 A1 and US 2004/0131151 A1, the disclosures of which are incorporated herein by reference, and the aforementioned US Pat. No. 6,895,075. Is disclosed. Alternatively or in addition, optical methods for tilt measurement may be used, for example, as described in US Pat. No. 6,643,354, the disclosure of which is incorporated herein by reference. The inclination map is recorded in the system control unit (which may be performed by the processing unit 56 as described above).

After the tilt map is generated, in the mode setting step 102, the light source assembly 26 and the detector element assembly 32 are set for SAXS measurement as described above. Next, in the site selection step 104, the stage 24 is operated to move the sample 22 so that the X-ray beam 74 collides with a desired test site. Usually, multiple sites on the sample 22 are preselected for this purpose, and the stage 24 moves the sample so that each site is placed in sequence within the region 50. In the inclination determination step 106, the system control unit checks the recorded inclination value of the part on the inclination map. Alternatively, when there is no recorded inclination value for the specific part, the system control unit may check the inclination value of the adjacent point on the inclination map and detect the approximate inclination value of the test part by interpolation. As shown in FIG. 2, when the XRR beam axis and the SAXS beam axis are deviated from each other, the inclination value may be converted by rotation to cancel the angle deviation in the XY plane.

Next, in an inclination correction step 108, the system control unit instructs the stage 24 to adjust the orientation angle of the sample 22 to compensate for the inclination at the current test site. In other words, if it is determined from the tilt map that the current test site is tilted + 0.1 ° about the X axis, the stage 24 adds a tilt of −0.1 °. Alternatively, the X-ray beam axis of the light source assembly 26 may be adjusted to compensate for sample tilt. When the tilt is properly adjusted, in data collection step 110, the light source assembly and detector element assembly are activated and the processor 56 collects and analyzes the SAXS spectrum of the test site. This process is then repeated for the remaining test sites.

While the embodiments described above deal primarily with determining the surface layer characteristics of a semiconductor wafer, the principles of the present invention are not limited to other applications of X-ray-based analysis, as well as other It can be used in the same way for analyzes based on other types of irradiation, also using an ionization irradiation zone. In addition, to incorporate other methods of analysis based on irradiation, such as, for example, X-ray fluorescence measurements, as described in US Pat. No. 6,381,303, the disclosure of which is incorporated herein by reference. In addition, the system 20 may be changed. Alternatively or in addition, the system 20 is assigned to the assignee of the present patent application, the disclosure of which is incorporated herein by reference, US patent application Ser. No. 10 / 902,177 (July 30, 2004). As described in Japanese application), it may be configured to perform diffusion XRR measurements.

Further, while the features of the present invention have been described above in connection with a system 20 that combines a plurality of different x-ray analysis modes, as an alternative, some of these features may be SAXS, XRD (high angle Or may be incorporated into a system that provides only one or two modes of operation, such as grazing angle) and / or XRR.

The principles of the present invention may also be applied to measurement systems and tools for use in a production environment. For example, in an alternative embodiment (not shown) of the present invention, the elements of system 20 are integrated with a semiconductor wafer fabrication tool in order to perform in-situ inspection. As is known in the art, a fabrication tool typically includes a vacuum chamber that includes a vapor deposition apparatus to form a thin film on a wafer. For example, the chamber has an x-ray window, as described in US Patent Publication US2001 / 0043668 A1, whose disclosure is incorporated herein by reference. The x-ray source assembly 26 may then irradiate the region 50 on the wafer through one of the windows, with one or more of the XRR, XRD or SAXS configurations as described above, separate from the detector element assembly 32. The scattered X-rays are received through the window. In another alternative embodiment, the system 20 may be configured as a collective tool station used to perform manufacturing processes with other stations.

  Therefore, it will be apparent that the above-described embodiments have been given by way of example, and that the present invention is not limited to what has been particularly shown and described hereinabove. The scope of the present invention is the various feature combinations and sub-combinations described above, as well as those that can be conceived by those skilled in the art upon reading the above description and which are not disclosed in the prior art. Includes variations and modifications.

1 is a schematic side view of an X-ray measurement system according to an embodiment of the present invention. 1 is a schematic top view of an X-ray measurement system according to an embodiment of the present invention. 1 is a schematic front view of a detector element array configured for XRR, in accordance with one embodiment of the present invention. FIG. 1 is a schematic front view of a detector element array configured for SAXS, according to one embodiment of the present invention. FIG. 1 is a schematic top view of a SAXS measurement system according to an embodiment of the present invention. FIG. FIG. 2 is a schematic illustration of the details of a knife edge used to control the focus of an x-ray beam incident on a surface, in accordance with one embodiment of the present invention. 4 is a flowchart schematically illustrating a SAXS measurement method according to an embodiment of the present invention.

Explanation of symbols

20: System 22: Sample 24: Stage 26: X-ray source 28, 40: Light source operation assembly 30, 36: The operation assembly is a curved trajectory 32: Detection element assembly 34: Detection element operation assembly 38: Tube 42: Optical element 44: Convergent beam 46: Shutter 48: Knife edge 50: Area 54: Array 56: Processing unit 58: Distribution 70: Scattered beam 72: Collimating optical element 74: X-ray beam 75: Light source beam blocking unit 76: Detection element 80: Slit 82: Diffraction prevention slit 86: Window 88: Housing 90: Wire 100: Inclination mapping step 102: Mode setting step 104: Site selection step 106: Inclination determination step 108: Inclination correction step

Claims (50)

A sample analyzer comprising:
An irradiation source configured to direct a first X-ray focused beam to the sample surface and a second X-ray parallel beam to the sample surface;
A first light source position at which the X-ray is directed from the irradiation source to the sample surface at a grazing angle, and the X-ray is directed from the irradiation source to the sample surface in the vicinity of the Bragg angle of the sample. An operative assembly operable to move between a second light source position;
Sensing the X-rays scattered from the sample as a function of angle when the illumination source is in either of the first and second light source configurations and in either of the first and second light source positions A sensing element assembly configured to generate an output signal in response to the scattered x-rays;
A sample analyzer comprising: a signal processing unit coupled to receive and process the output signal and to determine a property of the sample. The irradiation source is
An X-ray tube operating to emit said X-rays;
A first mirror configured to receive the x-ray and focus the focused beam;
The apparatus according to claim 1, comprising: a second mirror configured to receive the X-ray and focus it into the parallel beam.   The apparatus of claim 2, wherein the first and second mirrors have a double curved structure.   The motion assembly has a first detection element elevation angle that senses the X-rays that the detection element assembly has scattered from the sample at a grazing angle, and the X-rays that the detection element assembly has scattered from the surface in the vicinity of a Bragg angle. The apparatus of claim 1, wherein the apparatus is operative to move the sensing element assembly between a second sensing element elevation angle that senses. The motion assembly includes the detection element assembly at an elevation angle of the first detection element, a first azimuth angle at which the detection element assembly senses small angle scattering of the X-ray, and the detection element assembly is positioned on the surface of the sample. Operating to move between a second larger azimuth angle that senses the X-rays diffracted from in-plane structures;
The apparatus according to claim 4.   The detection element assembly has a first detection element configuration for resolving the scattered X-ray along a first axis perpendicular to the sample surface, and the scattered along a second axis parallel to the surface. The apparatus of claim 1, comprising a detector element array having a second detector element configuration for resolving x-rays.   The signal processing unit processes the output signal from the detection element assembly in the first detection element configuration to determine a reflectance from the surface as a function of an elevation angle with respect to the surface; The apparatus of claim 6, configured to process the output signal from the sensing element assembly in a sensing element configuration to determine the scattering properties of the surface as a function of the azimuth angle of the surface plane.   The signal processing unit processes the output signal from the detection element assembly when the irradiation source irradiates the first beam and is at the first light source position, so that X-rays on the surface Acquiring a reflectance (XRR) spectrum, processing the output signal from the detector element assembly when the illumination source illuminates the second beam and is in the first light source position; Acquiring at least one of a surface X-ray small angle scattering (SAXS) spectrum and a small angle X-ray diffraction (XRD) spectrum, and the output from the detection assembly when the illumination source is at the second light source position; The apparatus of claim 1, configured to process a signal to obtain a high angle XRD spectrum of the surface.   The signal processing unit acquires a high-resolution XRD spectrum when the irradiation source is at the second light source position and irradiates the first beam, and the irradiation source is at the second light source position. 9. The apparatus of claim 8, wherein the apparatus is configured to acquire a low resolution XRD spectrum when irradiating the second beam.   The detector element assembly is positioned at a first distance from the sample surface such that a motion sensor acquires the high resolution XRD spectrum, and the detector element assembly is acquired to acquire the low resolution XRD spectrum; The apparatus of claim 9, wherein the apparatus is configured to be disposed at a second distance from the surface that is less than the first distance.   The sample comprises at least one surface layer, and the signal processor is configured to analyze two or more of the XRR, SAXS and XRD spectra together to determine a property of the at least one surface layer; The apparatus according to claim 8.   The apparatus of claim 11, wherein the characteristics include at least one of film thickness, density, surface quality, porosity, and crystal structure.   A knife edge disposed parallel to the sample surface and adjacent to the selected area, defining a gap between the surface and the knife edge to block a portion of the beam that does not pass through the gap The apparatus of claim 1.   A beam blocking unit configured to block the X-rays that pass through the gap and propagate along the beam axis without blocking the X-rays scattered in a target angle range. Item 14. The device according to Item 13.   The apparatus of claim 13, wherein the knife edge comprises a cylinder of x-ray absorbing material.   A mounting assembly for receiving and adjusting the orientation of the sample during analysis, wherein the illumination source is configured to direct the X-ray beam to a selected region of the sample surface; An inclination map showing a characteristic inclination angle is determined, an inclination angle of the selected region is determined based on the inclination map, and the orientation of the sample is adjusted by the mounting assembly to compensate the estimated inclination angle. The apparatus of claim 1, configured to: An irradiation source configured to direct an X-ray parallel beam along a beam axis at a grazing angle to a selected region of the sample surface and to scatter a portion of the X-ray from the region within an azimuthal range;
A knife edge disposed parallel to the sample surface and adjacent to the selected region, defining a gap between the surface and the knife edge, and blocking a portion of the beam that does not pass through the gap;
A beam blocker configured to block X-rays that pass through the air gap and further propagate along the beam axis without blocking X-rays scattered in at least a portion of the azimuthal range;
A sensing element assembly configured to sense the scattered x-rays as a function of azimuth and to generate an output signal in response to the scattered x-rays;
A sample analyzer comprising: a signal processing unit coupled to receive and process the output signal and to determine a property of the sample.   At least one slit disposed perpendicular to the sample surface and between the irradiation source and the knife edge, allowing at least a portion of the parallel beam to pass through while blocking the scattered X-rays. Item 18. The device according to Item 17.   The apparatus of claim 18, wherein the at least one slit comprises a first slit disposed proximate to the irradiation source and a second slit disposed proximate to the knife edge. The sensing element assembly comprises:
An array of detector elements having an array length;
An evacuable housing having a front surface and a back surface separated by a distance equal to at least the array length, the array being disposed on the back surface of the housing, the housing comprising a window on the front surface, and radiating The apparatus of claim 17, wherein the apparatus is configured to allow light to pass through it and strike the array.   The apparatus of claim 17, wherein the knife edge comprises a cylinder of x-ray absorbing material. An irradiation source configured to direct X-rays to a selected region of the sample and to scatter a portion of the X-rays from the region;
X-ray absorption, positioned parallel to the sample surface and adjacent to the selected area, defining a gap between the surface and a knife edge to block a portion of the beam that does not pass through the gap A knife edge with a cylinder of material;
A sensing element assembly configured to sense the scattered x-rays as a function of angle and generate an output signal in response to the scattered x-rays;
A sample analyzer comprising: a signal processing unit coupled to receive and process the output signal and to determine the characteristics of the sample.   23. The apparatus of claim 22, wherein the x-ray absorbing material cylinder comprises a metal wire. A mounting assembly for receiving and adjusting the orientation of the sample during analysis;
An irradiation source configured to direct a parallel X-ray beam to a selected region of the sample surface on the mounting assembly, and to scatter a portion of the X-ray from the region in an azimuthal range;
A sensing element assembly configured to sense the scattered x-rays as a function of azimuth and to generate an output signal in response to the scattered x-rays;
An inclination map indicating a characteristic inclination angle of the surface is received, an inclination angle of the selected region is determined based on the inclination map, and the orientation of the sample in the mounting assembly in response to the estimated inclination angle And a signal processing unit coupled to receive the output signal after adjusting the orientation and process the output signal to determine the characteristics of the sample.   The illumination source is configured to direct the focused beam of X-rays to each of a plurality of positions on the surface, and the detection element assembly senses the X-rays reflected from the surface as a function of an elevation angle relative to the surface. The signal processing unit measures an X-ray reflectivity (XRR) spectrum of each position in response to the reflected X-ray, and determines an inclination angle of each position based on the XRR spectrum. 25. The device according to claim 24. Manipulating the irradiation source to direct a first X-ray focused beam to the sample surface and a second X-ray parallel beam to the sample surface;
A first light source position at which the X-ray is directed from the irradiation source to the sample surface at a grazing angle, and the X-ray is directed from the irradiation source to the sample surface in the vicinity of the Bragg angle of the sample. Move between the second light source position,
Sensing the x-rays scattered from the sample as a function of angle when the illumination source is in both the first and second light source configurations and in both the first and second light source positions; Sample analysis method for determining characteristics of the sample. The irradiation source is
Arranging a first mirror for condensing the X-ray from an X-ray source into the convergent beam;
27. A method according to claim 26, characterized in that a second mirror is provided for condensing the X-rays from the X-ray source into the parallel beam.   28. The method of claim 27, wherein the first and second mirrors have a double curved structure.   Sensing the X-ray captures the scattered X-rays using a detection element, and the detection element is removed from the sample when the irradiation source is at the first light source position. A first detection element elevation angle that senses the X-rays scattered at a grazing angle, and the X of the detection element scattered from the surface in the vicinity of a Bragg angle when the irradiation source is at the second light source position. 27. The method of claim 26, wherein the detection element is moved between a second detection element elevation angle that senses a line.   Moving the detection element includes: detecting the detection element at an elevation angle of the first detection element; a first azimuth angle at which the detection element assembly senses small angle scattering of the X-ray; 30. The method of claim 29, further comprising moving between a second larger azimuth angle that senses the x-ray diffracted from the in-plane structure of the sample surface.   Sensing the x-ray includes a first detector element configuration that resolves the scattered x-ray along a first axis perpendicular to the sample surface, and a second axis parallel to the surface. 27. Method according to claim 26, characterized in that it is arranged in a second detection element configuration for resolving the scattered X-rays.   Sensing the X-ray processes the output of the detector element array in the first detector element configuration to determine reflectivity from the surface as a function of elevation relative to the surface; 31. The method of claim 30, wherein the output of the detector element array in a detector element configuration is processed to determine the scattering properties of the surface as a function of the azimuth angle of the surface plane.   Sensing the X-ray obtains an X-ray reflectivity (XRR) spectrum of the surface when the illumination source is at the first light source position and directing the first beam to the surface. Then, when the irradiation source is at the first light source position and directs the first beam to the surface, an X-ray small angle scattering (SAXS) spectrum and a small angle X-ray diffraction (XRD) spectrum of the surface 27. The method of claim 26, wherein at least one of the following is acquired and a high angle XRD spectrum of the surface is acquired when the illumination source is at the second light source position.   Acquiring the XRD spectrum is to acquire a high resolution XRD spectrum when the illumination source is at the second light source position and directing the first beam to the surface, and the illumination source is 34. The method of claim 33, wherein a low resolution XRD spectrum is acquired when the second beam is at two light source positions and the second beam is directed at the surface.   Sensing the X-rays arranges a detector element to receive the scattered X-rays at a first distance from the sample surface to obtain the high resolution XRD spectrum, and the low resolution XRD spectrum. 35. The detection element of claim 34, wherein the detection element is arranged to receive the scattered X-rays at a second distance from the surface that is less than the first distance to obtain Method.   34. The sample of claim 33, wherein the sample comprises at least one surface layer, and wherein two or more of the XRR, SAXS and XRD spectra are analyzed together to determine characteristics of the at least one surface layer. The method described.   37. The method of claim 36, wherein the properties include at least one of film thickness, density, surface quality, porosity, and crystal structure.   Placing a knife edge parallel to the sample surface and adjacent to the selected area, defining a gap between the surface and the knife edge, and blocking a portion of the beam that does not pass through the gap. 28. The method of claim 27, wherein:   A beam blocking unit that blocks the X-rays that pass through the gap and propagate along the beam axis without blocking the X-rays scattered in a target angle range is characterized by: 40. The method of claim 38.   40. The method of claim 38, wherein the knife edge comprises a cylinder of x-ray absorbing material. Manipulating the irradiation source directs the X-ray beam to a selected region of the sample surface;
Providing an inclination map showing a characteristic inclination angle of the surface;
Determining an inclination angle of the selected area based on the inclination map;
28. The method of claim 27, wherein the sample orientation is adjusted to compensate for the estimated tilt angle. Directing an X-ray parallel beam at a grazing angle along the beam axis toward a selected region of the sample surface such that a portion of the X-ray scatters from the region within an azimuthal range;
A knife edge is placed parallel to the sample surface and adjacent to the selected area to define a gap between the surface and the knife edge to block a portion of the beam that does not pass through the gap. And
A beam blocking unit is arranged to block the X-rays that pass through the gap and propagate along the beam axis without blocking the X-rays scattered in at least a part of the azimuth range,
A sample analysis method for determining characteristics of a sample by sensing the scattered X-ray as a function of azimuth angle.   At least one slit is disposed perpendicularly to the sample surface between the light source of the X-ray parallel beam and the knife edge, and the parallel beam blocks the scattered X-ray while the at least one slit blocks the scattered X-ray. 43. The method of claim 42, wherein at least a portion of the is passed.   44. The method of claim 43, wherein the at least one slit comprises a first slit disposed proximate to the irradiation source and a second slit disposed proximate to the knife edge.   43. The method of claim 42, wherein the knife edge comprises a cylinder of x-ray absorbing material. Directing an X-ray beam to a selected region of the sample such that a portion of the X-ray is scattered from the region;
A cylinder of X-ray absorbing material is disposed parallel to the sample surface and adjacent to the selected region to define a gap between the surface and the cylinder, and to prevent the beam from passing through the gap. Block the part,
A sample analysis method for determining characteristics of a sample by sensing the scattered X-ray as a function of angle.   47. The method of claim 46, wherein the cylinder of x-ray absorbing material comprises a metal wire. Generate a sample tilt map,
Directing an X-ray parallel beam at a grazing angle along the beam axis toward a selected region of the sample, such that a portion of the X-ray is scattered from the region within an azimuthal range;
Determining an inclination angle of the selected area based on the inclination map;
Adjusting the orientation of the sample to compensate for the tilt angle;
A sample analysis method for determining the characteristics of a sample by sensing the scattered X-rays as a function of azimuth after adjusting the orientation.   Generating the tilt map is characterized by measuring an X-ray reflectivity (XRR) spectrum from each of a plurality of positions on the surface and determining a tilt angle of each position based on the XRR spectrum; 49. The method of claim 48.   The XRR spectrum is measured by directing the X-ray convergent beam to each of the plurality of positions and detecting the X-ray reflected from the surface as a function of an elevation angle with respect to the surface. 49. The method according to 49.

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