Semiconductor detection device, detection method and semiconductor device with process chamber

Abstract

The present invention provides a semiconductor detection device, a detection method and a semiconductor process device, wherein the detection device comprises: a wafer carrying device for carrying a wafer to be detected; an incident light system for emitting a first incident light; a beam shaping system for shaping the first incident light into a first annular incident light, the first annular incident light being reflected by the wafer to be detected to form a first reflected light; an optical signal sorting system for sorting out a nonlinear optical signal from the first reflected light; and a control system for obtaining first defect information of the wafer to be detected according to the nonlinear optical signal. The present invention is used to realize non-destructive atomic-level defect detection in a process, while eliminating the anisotropy of nonlinear optical signals in the detection process.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a semiconductor detection device, a detection method and a semiconductor device with a process chamber. Background Art

[0002] In the semiconductor manufacturing process, defects in process or materials can easily cause device yield to decrease and increase production costs. The existing conventional yield detection methods are divided into electrical detection and online quantity detection.

[0003] Among them, electrical testing can be used to find defects that affect the electrical performance of devices. However, conventional electrical testing can only be applied to the back end of line (BEOL) or packaging testing, and cannot find and solve problems in real time during the process. That is, the period from the occurrence of electrical testing to the detection of problems is too long, which easily leads to the waste of invalid processes, and the detection speed is slow, and batch detection cannot be achieved.

[0004] Another traditional online quantitative inspection can realize real-time inspection in the process, such as scanning electron microscope inspection, optical bright field inspection, etc., but its inspection type has limitations. Specifically, online quantitative inspection is usually applicable to macroscopic physical defects, such as particles and pattern defects. Once the inspection requirements enter the atomic size level defects, online quantitative inspection cannot meet the inspection requirements.

[0005] In summary, real-time detection of atomic-level defects caused by the use of new materials and process flows in advanced process R&D and production is one of the issues that urgently need to be addressed in the field of semiconductor yield testing. Summary of the invention

[0006] The problem solved by the present invention is to provide a semiconductor detection device, a detection method and a semiconductor device with a process chamber, which are used to realize non-destructive atomic-level defect detection in the process and eliminate the anisotropy of nonlinear optical signals in the detection process.

[0007] To solve the above problems, the present invention provides a semiconductor detection device, including: a wafer carrying device, used to carry a wafer to be detected; an incident light system, which emits a first incident light; a beam shaping system, which shapes the first incident light into a first annular incident light, and the first annular incident light is reflected by the wafer to be detected to form a first reflected light; an optical signal sorting system, used to sort out a nonlinear optical signal from the first reflected light; and a control system, used to obtain first defect information of the wafer to be detected based on the nonlinear optical signal.

[0008] Optionally, the beam shaping system includes: a first axicon, used for converging the first incident light to form a first converging light; and a second axicon, used for diverging the first converging light to form the first annular incident light.

[0009] Optionally, a focusing unit is also included, and the focusing unit includes a lens.

[0010] Optionally, the lens further includes a through hole, and the through hole passes through the lens along the central axis of the lens.

[0011] Optionally, the nonlinear optical signal includes a second harmonic signal, a third harmonic signal, a sum frequency response signal and a difference frequency response signal.

[0012] Optionally, it also includes: a wafer alignment and focusing system, which includes: an imaging unit for obtaining imaging patterns at different positions on the surface of the wafer to be inspected; and a sensor for obtaining position information of the wafer to be inspected in a first direction, wherein the first direction is perpendicular to the surface of the wafer to be inspected.

[0013] Optionally, the control system includes: an imaging operation unit, used to obtain position information of the wafer to be inspected based on imaging patterns at different positions on the surface of the wafer to be inspected; a first position control unit, used to move the wafer carrier along a direction parallel to a reference plane according to the position information, so as to achieve alignment of the first annular incident light on the surface of the wafer to be inspected, and the reference plane is parallel to the surface of the wafer to be inspected.

[0014] Optionally, the control system includes: a second position control unit, configured to move the wafer carrying device according to the position information in the first direction, so as to achieve focusing of the first annular incident light on the surface of the wafer to be inspected.

[0015] Optionally, the incident light system includes: a first light source, used to emit a first initial incident light; a first incident light modulation unit, used to modulate the first initial incident light to form a first initial modulated incident light; and a spectrometer, used to form the first incident light emitted to the wafer to be inspected through the first initial modulated incident light.

[0016] Optionally, the first light source includes a laser emitter.

[0017] Optionally, it also includes: an optical collimation unit: used for collimating the first reflected light, and the collimated first reflected light is incident on the optical signal sorting system.

[0018] Optionally, it also includes: an optical collimation unit: used to collimate the first reflected light, and the collimated first reflected light passes through the beam shaping system and the beam splitter respectively and then enters the optical signal sorting system.

[0019] Optionally, the optical signal sorting system includes: a filter for passing a portion of the first reflected light having a preset wavelength range to form a first transition optical signal; and a polarizer for passing the first transition optical signal having preset polarization parameters to form the nonlinear optical signal.

[0020] Optionally, the optical signal sorting system includes: a polarizer for passing a portion of the first reflected light having preset polarization parameters to form a second transition optical signal; and a filter for passing the second transition optical signal having a preset wavelength range to form the nonlinear optical signal.

[0021] Optionally, it also includes: a main signal acquisition system, used for acquiring the nonlinear optical signal and transmitting the nonlinear optical signal to the control system.

[0022] Optionally, it also includes: an additional signal acquisition system, used to obtain an additional optical signal from the first reflected light and transmit the additional optical signal to the control system.

[0023] Optionally, the wafer carrying device includes: a carrying plate for carrying the wafer to be inspected; a fixing device arranged on the carrying plate for fixing the wafer to be inspected on the surface of the carrying plate; and a mechanical moving component for driving the carrying plate to move along a surface parallel to the wafer to be inspected.

[0024] Optionally, the wafer carrier device further includes a rotating device for driving the carrier plate to rotate along a central axis.

[0025] Optionally, the fixing device is a vacuum suction cup or a buckle fixed to the edge of the carrying plate.

[0026] Correspondingly, the present invention also provides a semiconductor device with a process chamber, comprising: a process chamber, wherein the process chamber has a process window; the above-mentioned semiconductor detection device, wherein the incident light system, the beam shaping system, the optical signal sorting system and the control system are located outside the process chamber, and the first annular incident light is vertically incident on the wafer to be detected through the process window.

[0027] Correspondingly, the present invention also provides a detection method using the above-mentioned semiconductor detection device, including: providing a wafer to be detected; emitting a first incident light; shaping the first incident light into a first annular incident light, and the first annular incident light is reflected by the wafer to be detected to form a first reflected light; obtaining the first reflected light, and sorting out a nonlinear optical signal from the first reflected light; and obtaining first defect information of the wafer to be detected based on the nonlinear optical signal.

[0028] Optionally, the wafer to be inspected includes: a substrate, and a dielectric layer located on a surface of the substrate.

[0029] Optionally, the first defect information includes interface electrical property defects at the interface between the substrate and the dielectric layer; the interface electrical property defects include: interface state charge potential well defects, dielectric layer inherent charge distribution and defects, and substrate semiconductor doping concentration.

[0030] Optionally, the wafer to be inspected includes: a substrate, and a semiconductor layer located on the surface of the substrate; the material of the semiconductor layer is a compound semiconductor material or a single semiconductor material.

[0031] Optionally, the compound semiconductor material includes gallium arsenide, gallium nitride or silicon carbide; and the formation process of the semiconductor layer includes an epitaxial process.

[0032] Optionally, the first defect information includes: crystal structure defects, internal stress distribution of the semiconductor layer, and epitaxial thickness of the semiconductor layer.

[0033] Optionally, the wafer carrying device includes: a carrying plate for carrying the wafer to be inspected; a fixing device arranged on the carrying plate for fixing the wafer to be inspected on the surface of the carrying plate; a mechanical moving component for driving the carrying plate to move; and a rotating device for driving the carrying plate to rotate along the central axis; the detection method includes: driving the mechanical moving component to make the carrying plate move in a straight line in a direction parallel to the surface of the wafer to be inspected, so that the incident point of the first annular incident light moves between the center and the edge of the carrying plate along the radial direction of the carrying plate; when driven by the mechanical moving component, the carrying plate is driven to rotate along the central axis of the carrying plate by the rotating device.

[0034] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0035] The incident light system emits a first incident light, and the first incident light is shaped into a first annular incident light under the action of the optical shaping system. In the first annular incident light reflected from the surface of the wafer to be detected, a nonlinear optical signal for detection is sorted out. On the one hand, the nonlinear optical signal can be used to characterize interface state charge potential well defects, dielectric layer inherent charges and defects, or semiconductor crystal structure defects, to achieve real-time non-destructive atomic-level defect detection of semiconductor devices in semiconductor manufacturing processes; on the other hand, the difference in azimuth angles of the wafer to be detected leads to the anisotropy of the nonlinear signal, and the azimuth angle depends on the angle between the incident surface and the lattice orientation. When the first annular incident light is used as the incident light, the difference in azimuth angle becomes the superposition of the differences in several azimuth angles, eliminating the difference in azimuth angle. Since the difference in azimuth angle is eliminated, the anisotropy of the nonlinear signal is also eliminated. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figures 1 to 11 It is a schematic structural diagram of a semiconductor detection device and a semiconductor device with a process chamber according to various embodiments of the present invention;

[0037] Fig.12 is a scanning trajectory diagram of the first annular incident light in an embodiment of the present invention;

[0038] Fig.13 It is a schematic flow chart of the detection method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0039] As described in the background art, achieving real-time atomic-level defect detection during the manufacturing process is one of the problems that need to be solved urgently in the field of semiconductor yield detection.

[0040] In order to solve the problem of real-time detection of atomic-level defects caused by new materials and process flows in the research and development and production of advanced semiconductor processes, an embodiment of the present invention provides a semiconductor detection device and a detection method. By incident annular light on the surface of a wafer to be detected, not only can various anisotropies of the wafer to be detected during the detection process be eliminated, but also nonlinear optical signals for detection can be sorted out from the first reflected light to characterize interface state charge potential well defects, dielectric layer inherent charges and defects, or semiconductor crystal structure defects, thereby realizing non-destructive atomic-level defect detection of semiconductor devices.

[0041] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0042] Figures 1 to 9 Schematic diagram of the structure of the semiconductor detection device according to each embodiment of the present invention.

[0043] Please refer to Figure 1 , the structure of the semiconductor detection device includes:

[0044] The wafer carrying device 100 is used to carry the wafer 101 to be tested;

[0045] An incident light system 200 emits a first incident light 210;

[0046] The beam shaping system 300 shapes the first incident light 210 into a first annular incident light 310, and the first annular incident light 310 is reflected by the wafer to be inspected to form a first reflected light 311;

[0047] An optical signal sorting system 400, used for sorting out a nonlinear optical signal 312 from the first reflected light 311;

[0048] The control system 500 is used to obtain the first defect information of the wafer to be inspected according to the nonlinear optical signal 312.

[0049] In this embodiment, the anisotropy of the nonlinear signal can be eliminated by shaping the first incident light 210 into the first annular incident light 310 using the beam shaping system 300. This is because the deviation of the nonlinear optical signal comes from the azimuth error, and the first annular incident light 310 is vertically incident on the surface of the wafer 101 to be detected, so that the azimuth error becomes the superposition of several azimuth errors, eliminating the difference in azimuth errors at different positions, and the deviation of the nonlinear optical signal also becomes the superposition of several azimuth errors, thereby eliminating the anisotropy of the nonlinear optical signal.

[0050] In this embodiment, the azimuth angle refers to the relative angle between the incident plane and any specific direction representing the orientation of the wafer (for example, a wafer notch or a specific crystal axis direction).

[0051] The following is a detailed description with reference to the accompanying drawings.

[0052] The semiconductor detection device can characterize the atomic-level defects in the wafer 101 to be detected through the nonlinear optical signal 312, so as to obtain the atomic-level defects or crystal defects in the wafer in real time and non-destructively during the process.

[0053] Specifically, by incidenting the first annular incident light 310 to the position to be tested on the surface of the wafer 101 to be tested, the material of the wafer 101 to be tested interacts with the light field emission of the first annular incident light 310 to generate an optical response, and the nonlinear optical signal 312 in the optical response can be used to characterize the atomic-level defects in the wafer 101 to be tested. Since optical detection means are used, there is no need to perform destructive detection on the wafer 101 to be tested, and the optical detection can be performed at certain key nodes in the process, thereby realizing real-time discovery of defects and timely improvement of the process.

[0054] The nonlinear optical signal 312 includes a sum frequency response (SFG), a difference frequency response (DFG), a second harmonic signal (SHG), a third harmonic signal (THG) and higher-order nonlinear optical signals.

[0055] In this embodiment, please refer to Figure 2, the wafer to be inspected 101 includes: a substrate 110, and a dielectric layer 111 located on the surface of the substrate 110; in this embodiment, the material of the substrate 110 is single crystal silicon, and the material of the dielectric layer 111 is silicon oxide. In other embodiments, the material of the substrate 110 can also be other semiconductor materials with central symmetry; the material of the dielectric layer 111 is other dielectric materials, such as silicon nitride, silicon oxynitride, high-K dielectric materials (dielectric constant greater than 3.9), low-K dielectric materials (dielectric constant greater than 2.5 and less than 3.9) or ultra-low-K dielectric materials (dielectric constant less than 2.5).

[0056] The nonlinear optical signal 312 can characterize the interfacial charge trap defects (Dit: interfacial trap density) at the interface between the dielectric layer 111 and the substrate 110, as well as the intrinsic charges and defects in the dielectric layer. The interfacial charge trap defects are distributed at the interface between the semiconductor and the oxide film; the intrinsic charges and defects in the dielectric layer are distributed inside the dielectric layer. The intrinsic charges and defects in the dielectric layer 111 are intrinsic defects introduced by process factors during the film formation process of the dielectric layer 111, and may also be material damage caused by subsequent processes. The interfacial charge trap defects or the intrinsic charges and defects in the dielectric layer may cause the degradation of the electrical properties between the dielectric layer 111 and the substrate 110.

[0057] Specifically, since the material of the substrate 110 is single crystal silicon, and the single crystal silicon is a centrosymmetric material, when there is an interface state charge A at the interface between the dielectric layer 111 and the substrate 110, or there is an intrinsic charge B inside the dielectric layer 111, the interface state charge A or the intrinsic charge B will induce a change in the spatial charge distribution inside the substrate 110. Once the spatial charge distribution inside the substrate changes, the single crystal silicon material will generate an electric field induced signal due to the destruction of the centrosymmetry. After the nonlinear optical signal 312 is coupled with the electric field induced signal, it can reflect the change in the spatial charge distribution inside the substrate 110, and then characterize the interface state charge potential well defect distribution at the interface between the dielectric layer 111 and the substrate 110, or the intrinsic charge and defect distribution inside the dielectric layer 111.

[0058] In one embodiment, the dielectric layer 111 is patterned. In another embodiment, the dielectric layer 111 is not patterned.

[0059] In another embodiment, please refer to Figure 3The wafer 101 to be inspected includes: a substrate 120, and a semiconductor layer 121 located on the surface of the substrate 120; the material of the semiconductor layer 121 is a compound or a single semiconductor material; the compound semiconductor material includes gallium arsenide, gallium nitride, and silicon carbide. The nonlinear optical signal 312 can respond to the crystal structure defects in the compound semiconductor material, thereby achieving real-time monitoring of the crystal quality of the semiconductor layer 121.

[0060] In this embodiment, the semiconductor layer is formed on the surface of the substrate by an epitaxial process. When the epitaxial process causes a crystal structure defect in the semiconductor layer, the crystal structure defect is coupled with the nonlinear optical signal 312, so that the nonlinear optical signal 312 can characterize the lattice defect or the crystal uniformity defect. The crystal structure defect includes a lattice defect or a crystal uniformity defect, and the crystal uniformity defect refers to a defect where the orderly arrangement of the lattice is distorted.

[0061] In one embodiment, the semiconductor layer 121 is patterned. In another embodiment, the semiconductor layer 121 is not patterned.

[0062] Please continue to refer to Figure 1 In this embodiment, the incident light system 200 includes: a first light source 201, used to emit a first initial incident light; a first incident light modulation unit 202, used to modulate the first initial incident light to form a first initial modulated incident light; a spectrometer 203, used to form the first incident light 210 emitted to the beam shaping system through the first initial modulated incident light.

[0063] In this embodiment, the first light source 201 includes a laser emitter.

[0064] refer to Figure 4 In this embodiment, the first incident light modulation unit 202 includes: a modulation device 220, used to change one or more of the light intensity, polarization parameters and focal length of the first initial incident light 2011; a monitoring device 221, used to monitor the incident light information of the first initial modulated incident light 2012, and feed back the incident light information to the control system 500.

[0065] The incident light information includes: power, light intensity, polarization parameters and focal length, etc.

[0066] Please refer to Figure 5 The beam shaping system 300 includes a first axicon 301 for converging the first incident light 210 to form a first converging light 211 ; and a second axicon 302 for diverging the first converging light 211 to form the first annular incident light 310 .

[0067] In this embodiment, since the beam shaping system 300 shapes the incident light into the first annular incident light 310, when the first annular light is incident on the wafer 101 to be inspected, the deviation of the nonlinear signal 312 is no longer an error dependent on part of the azimuth angle, but an error dependent on all azimuth angles, so that the anisotropy of the nonlinear signal 312 is eliminated.

[0068] Continue to refer Figure 5 , further comprising the focusing unit 303, wherein the focusing unit 303 comprises a lens 304, and the focusing unit 303 focuses the first annular incident light 310 onto the surface of the wafer 101 to be inspected.

[0069] In this embodiment, the lens 304 is a single lens; in other embodiments, the lens 305 may also be a lens group or a gradient refractive index lens or other curved mirror to achieve the same function.

[0070] In another embodiment, the lens 304 further includes a through hole, and the through hole passes through the lens 304 along the central axis of the lens 304 .

[0071] In this embodiment, the through holes can be used to place some components, thereby saving space.

[0072] In this embodiment, the collimated Gaussian light beam is shaped into a first annular light beam 310 (Bessel) light beam by the beam shaping system 300 and focused on the wafer 101 to be detected. Although the first annular light beam 310 is vertically incident on the surface of the wafer 101 to be detected, the incident angle is not zero, and the incident angle is determined by the diameter and the focal length. Therefore, the incident angle of the focused beam can be adjusted by the diameter of the first annular incident light 310. Due to the vertical incidence method, the beam shaping system 300 has a high degree of integration, a small occupied volume, and good flexibility in adjusting the incident angle. At the same time, due to the first annular incident light 310, the focused spherical aberration can be greatly reduced.

[0073] In this embodiment, the nonlinear signal 312 comes from the focused first annular light beam. Since the first annular incident light 310 is in a ring shape, the anisotropy from the wafer 101 to be inspected is automatically eliminated because the signal is an integral over all azimuth angles, and thus all azimuth angle dependencies disappear.

[0074] At the same time, the signal is no longer dependent on the azimuth I ( φ )∝∣ P ( φ )∣ 2 , becomes the coherent superposition of all azimuth angles in φIndicates: azimuth; I Represents: the total signal integrated over all azimuths; P It means that the signal at each azimuth angle will not affect the nonlinear signal 312 when the wafer 101 to be inspected rotates.

[0075] Please refer to Figure 6 , the optical signal sorting system 400 includes: an optical filter 401 and a polarizer 402. In this embodiment, the optical filter 401 is used to pass a portion of the first reflected light 311 having a preset wavelength range to form a first transition optical signal; the polarizer 402 is used to pass the first transition optical signal having a preset polarization parameter to form the nonlinear optical signal 312. That is, the first reflected light 311 is first filtered by the optical filter 401, and then passes through the polarizer 402 to filter out the nonlinear optical signal 312 having the preset polarization parameter.

[0076] Please refer to Figure 7 In another embodiment, the polarizer 402 is used to pass a portion of the first reflected light 311 having preset polarization parameters to form a second transition optical signal; the filter 401 is used to pass the second transition optical signal having a preset wavelength range to form the nonlinear optical signal 312.

[0077] Please continue to refer to Figure 1 In this embodiment, the control system 500 includes: an imaging operation unit 501, which is used to obtain the position information of the wafer to be detected according to the imaging patterns at different positions on the surface of the wafer 101 to be detected; a first position control unit 502, which is used to move the wafer carrier 100 along a direction parallel to a reference plane XY according to the position information, and the reference plane XY (i.e., a plane formed by an X coordinate and a Y coordinate) is parallel to the surface of the wafer 101 to be detected, so as to realize the alignment of the wafer 101 to be detected.

[0078] Please continue to refer to Figure 1 In this embodiment, the semiconductor detection device further includes a wafer alignment and focusing system 600, and the wafer alignment and focusing system 600 is used to align the first annular incident light 310 with the position to be detected on the surface of the wafer 101 to be detected and perform focusing.

[0079] The wafer alignment and focusing system 600 includes: an imaging unit 601, used to obtain imaging patterns at different positions on the surface of the wafer 101 to be detected; a sensor 602, used to obtain position information of the wafer 101 to be detected in a first direction Z, and the first direction Z is perpendicular to the surface of the wafer 101 to be detected.

[0080] After the imaging unit 601 obtains imaging patterns at different positions on the surface of the wafer 101 to be inspected, the control system 500 can obtain position information of the wafer 101 to be inspected through the imaging patterns, and then control the wafer carrier 100 to move to a desired position for alignment.

[0081] In this embodiment, the control system 500 further includes: a second position control unit 503 for moving the wafer carrying device 100 according to the position information of the wafer 101 to be inspected in the first direction Z.

[0082] After the sensor 602 obtains the position information of the wafer 101 to be inspected in the first direction Z, the position information is sent to the second position control unit 503. The second position control unit 503 moves the wafer carrier 100 according to the position information in the first direction Z until the first annular incident light 310 can be focused at a specified height on the surface of the wafer 101 to be inspected.

[0083] Please continue to refer to Figure 1 and Figure 4 The modulation device 220 is used to adjust the optical parameters of the initial incident light 2011. The monitoring device 221 can monitor the parameters of the initial incident light 2011 in real time, and feed back the incident light information obtained by monitoring to the control system 500. The control system 500 can control the modulation device 220 to adjust the optical parameters of the initial incident light 2011 according to the incident light information obtained.

[0084] refer to Figure 8 The semiconductor detection device also includes an optical collimation unit 305: used to collimate the first reflected light, and the collimated first reflected light is incident on the optical signal sorting system 400.

[0085] In another embodiment, referring to Fig. 9 The semiconductor detection device also includes an optical collimation unit 305: used to collimate the first reflected light, and the collimated first reflected light passes through the beam shaping system 300 and the beam splitter 203 respectively and then enters the optical signal sorting system 400.

[0086] Please continue to refer to Figure 1 In this embodiment, it also includes: a main signal acquisition system 320, which is used to obtain the nonlinear optical signal 312 and transmit the nonlinear optical signal to the control system 500.

[0087] In this embodiment, the first annular incident light 310 generates a first reflected light 311 on the surface of the wafer 101 to be inspected, and the optical signal sorting system 400 is used to sort out a nonlinear optical signal 312 from the first reflected light 311, and feed the nonlinear optical signal 312 back to the main signal acquisition system 320, and the main signal acquisition system 320 transmits the nonlinear optical signal to the control system 500.

[0088] Please continue to refer to Figure 1 In this embodiment, the semiconductor detection device further includes an additional signal acquisition system 700. In addition to generating the first reflected light 311 on the surface of the wafer 101 to be detected, the first annular incident light 310 also generates an additional reflected light 314; the additional signal acquisition system 700 is used to obtain an additional optical signal 315 from the additional reflected light 314, and transmit the additional optical signal 315 to the control system 500. The additional optical signal 315 can be used to characterize the second defect information, and the second defect information is used to complement the first defect information, so that the detection result is more comprehensive.

[0089] In one embodiment, the nonlinear optical signal 312 is used to characterize the first type of defect, and the additional optical signal 315 is used to characterize the second type of defect. Therefore, the nonlinear optical signal 312 and the additional optical signal 315 can achieve complementary detection results.

[0090] In another embodiment, the additional optical signal 315 can respond to both the third type of defect and the fourth type of defect, however, the additional optical signal 315 cannot distinguish between the third type of defect and the fourth type of defect. The nonlinear optical signal 312 can respond to the third type of defect but cannot respond to the fourth type of defect, so that the detection result of the additional optical signal 315 can be classified by the nonlinear optical signal 312, so that the accuracy of the detection result is improved.

[0091] Please continue to refer to Figure 1 In this embodiment, the additional signal acquisition system 700 obtains an additional optical signal through the additional reflected light 314, that is, the additional signal acquisition system 700 and the optical signal sorting system 400 obtain the reflected or scattered light formed by reflection or scattering of the incident light provided by the same light source.

[0092] In another embodiment, the additional signal acquisition system 700 and the optical signal sorting system 400 obtain reflected or scattered light resulting from reflection or scattering of incident light provided by different light sources.

[0093] The additional signal acquisition system 700 may be installed in the through hole of the lens of the focusing unit to reduce the volume occupied by the system.

[0094] The wafer carrier 100 comprises: a carrier plate for carrying the wafer 101 to be tested; a fixing device disposed on the carrier plate for fixing the wafer 101 to be tested on the surface of the carrier plate; and a mechanical moving component for driving the carrier plate to move. The fixing device is a vacuum suction cup or a buckle fixed to the edge of the carrier plate. The mechanical moving component can move the wafer 101 to the carrier plate according to the first position control unit 502 (such as Figure 1 ) or the second position control unit 503 (as shown Figure 1 The signal provided by the carrier plate moves the carrier plate to a specified position along a surface parallel to the wafer to be inspected.

[0095] Figure 10 to Figure 11 It is a schematic structural diagram of a semiconductor device with a process chamber according to various embodiments of the present invention.

[0096] refer to Fig.10 The wafer carrier 100 is placed in a process chamber 800, and a process window 801 is provided on the process chamber 800. The process window 801 is aligned with the beam shaping system 300, and the first annular incident light 310 can be vertically incident on the wafer to be inspected 101 through the process window 801, thereby realizing real-time detection of the wafer to be inspected 101.

[0097] In another embodiment, referring to Fig.11 The process chamber 800 also has a reaction opening 802, and the reaction opening 802 is used for reactants to flow into the process chamber 800 and react with the surface of the wafer 101 to be inspected, such as epitaxial growth.

[0098] The wafer carrier 100 also includes a rotating device for driving the carrier plate to rotate. After the dielectric layer 111 is patterned, a rotating device can also be used. When the mechanical moving component drives the carrier plate to move, the rotating device drives the carrier plate to rotate along the central axis to achieve the purpose of wafer defect detection.

[0099] refer to Fig.12 , when the wafer carrying device 100 rotates along the central axis under the action of the rotating device, the scanning trajectory of the first annular incident light 310 is shown. Fig.12 The straight arrow in a represents the translation trajectory of the first annular incident light 310, and the curved arrow represents the rotation direction of the wafer carrier 100. The first annular incident light 310 scans back and forth between the center of the carrier plate and the edge of the carrier plate along the translation trajectory. Fig.12b. The wafer carrier 100 is driven to rotate along the central axis by the rotating device to obtain a spiral scanning trajectory diagram of the first annular incident light 310 extending from the center to the edge of the carrier plate on the surface of the wafer to be inspected.

[0100] Accordingly, an embodiment of the present invention also provides a method for performing detection using the semiconductor detection device. Fig.13 , Fig.13 : is a flow chart of a detection method according to an embodiment of the present invention, comprising:

[0101] Step S1, providing a wafer to be inspected; Step S2, emitting a first incident light;

[0102] Step S3, shaping the first incident light into a first annular incident light, wherein the first annular incident light is reflected by the wafer to be inspected to form a first reflected light;

[0103] Step S4, acquiring the first reflected light, and sorting out a nonlinear optical signal from the first reflected light;

[0104] Step S5, obtaining first defect information of the wafer to be inspected according to the nonlinear optical signal.

[0105] The following is a detailed description with reference to the accompanying drawings.

[0106] Please refer to Figure 1 , Figure 2 and Figure 6 , providing a wafer 101 to be inspected.

[0107] In this embodiment, the wafer to be inspected 101 includes: a substrate 110, and a dielectric layer 111 located on the surface of the substrate 110; in this embodiment, the material of the substrate 110 is single crystal silicon, and the material of the dielectric layer 111 is silicon oxide. In other embodiments, the material of the substrate 110 can also be other semiconductor materials with central symmetry; the material of the dielectric layer 111 is other dielectric materials, such as silicon nitride, silicon oxynitride, high-K dielectric materials (dielectric constant greater than 3.9), low-K dielectric materials (dielectric constant greater than 2.5 and less than 3.9) or ultra-low-K dielectric materials (dielectric constant less than 2.5).

[0108] There is an interfacial charge trap defect (Dit: interfacial trap density) at the interface between the dielectric layer 111 and the substrate 110; or, there are inherent charges and defects in the dielectric layer. The interface charge trap defect is distributed at the interface between the semiconductor and the oxide film; the inherent charges and defects in the dielectric layer 111 are distributed inside the dielectric layer 111, and the inherent charge defects of the dielectric layer 111 are inherent defects introduced by process factors during the film formation process of the dielectric layer 111, and may also be material damage caused by subsequent processes. The interface charge trap defect or the inherent charge and defects of the dielectric layer 111 will cause the degradation of the electrical properties between the dielectric layer 111 and the substrate 110.

[0109] In another embodiment, please refer to Figure 1 , Figure 3 and Figure 7 The wafer 101 to be inspected includes: a substrate 120, and a semiconductor layer 121 located on the surface of the substrate 120; the material of the semiconductor layer 121 is a compound or a single semiconductor material; the compound semiconductor material includes gallium arsenide, gallium nitride, and silicon carbide; the formation process of the semiconductor layer includes an epitaxial process.

[0110] Combined with reference Figure 4 and Figure 1 , emitting the first incident light 210 .

[0111] Combined with reference Figure 5 and Figure 1 The first incident light 210 is shaped into a first annular incident light 310 , and the first annular incident light 310 is reflected by the wafer 101 to be inspected to form a first reflected light 311 .

[0112] Combined with reference Figure 8 and Figure 1 , obtain the first reflected light 311, and sort out the nonlinear optical signal 312 from the first reflected light 311.

[0113] In another embodiment, in combination with reference Fig. 9 and Figure 1 , obtain the first reflected light 311, and sort out the nonlinear optical signal 312 from the first reflected light 311.

[0114] In another embodiment, in combination with reference Figure 1 and Fig.10, the wafer 101 to be inspected is placed in the process chamber 800, and the process chamber 800 has a process window 801, and the process window 801 is aligned with the beam shaping system 300. The first annular incident light 310 can be vertically incident on the wafer 101 to be inspected through the process window 801, and the first reflected light 311 is obtained, and the nonlinear optical signal 312 is sorted out from the first reflected light 311, thereby realizing real-time detection of the wafer 101 to be inspected.

[0115] In another embodiment, in combination with reference Figure 1 and Fig.11 The process chamber 800 also has a reaction opening 802, and the reaction opening 802 is used for reactants to flow into the process chamber 800 and react with the surface of the wafer 101 to be detected, such as epitaxial growth, etc. The process window 801 is aligned with the beam shaping system 300, and the first annular incident light 310 can be vertically incident on the wafer 101 to be detected through the process window 801, and the first reflected light 311 is obtained, and a nonlinear optical signal 312 is sorted out from the first reflected light 311, so as to realize the monitoring of the wafer 101 to be detected during epitaxial growth. The nonlinear optical signal 312 represents the atomic-level defects in the wafer 101 to be detected, so as to realize the real-time non-destructive acquisition of atomic-level defects or crystal defects in the wafer during the process.

[0116] Specifically, by incidenting the first annular incident light 310 to the position to be tested on the surface of the wafer 101 to be tested, the material of the wafer 101 to be tested interacts with the light field emission of the first annular incident light 311 to generate an optical response, and the nonlinear optical signal 312 in the optical response can be used to characterize the atomic-level defects in the wafer 101 to be tested. Since optical detection means are used, there is no need to perform destructive detection on the wafer 101 to be tested, and the optical detection can be performed at key nodes in the process, thereby realizing real-time discovery of defects and timely improvement of the process.

[0117] In this embodiment, please refer to Figure 2 The wafer 101 to be inspected includes a substrate 110 and a dielectric layer 111 located on the surface of the substrate 110 .

[0118] The nonlinear optical signal 312 can characterize the interfacial charge trap defects (Dit: interfacial trap density) at the interface between the dielectric layer 111 and the substrate 110, as well as the intrinsic charges and defects in the dielectric layer. The interfacial charge trap defects are distributed at the interface between the semiconductor and the oxide film; the intrinsic charges and defects in the dielectric layer are distributed inside the dielectric layer. The intrinsic charges and defects in the dielectric layer 111 are intrinsic defects introduced by process factors during the film formation process of the dielectric layer 111, and may also be material damage caused by subsequent processes. The interfacial charge trap defects or the intrinsic charges and defects in the dielectric layer may cause the degradation of the electrical properties between the dielectric layer 111 and the substrate 110.

[0119] Specifically, since the material of the substrate 110 is single crystal silicon, which is a centrosymmetric material, when there is an interface state charge A at the interface between the dielectric layer 111 and the substrate 110, or there is an intrinsic charge B inside the dielectric layer 111, the interface state charge A or the intrinsic charge B will induce a change in the spatial charge distribution inside the substrate 110. Once the spatial charge distribution inside the substrate changes, the single crystal silicon material will generate an electric field induced signal due to the destruction of the centrosymmetry. After the nonlinear optical signal 312 is coupled with the electric field induced signal, it can reflect the change in the spatial charge distribution inside the substrate 110, and then characterize whether there is an interface state charge at the interface between the dielectric layer 111 and the substrate 110, or whether there is an intrinsic charge inside the dielectric layer 111.

[0120] In another embodiment, please refer to Figure 3 The wafer 101 to be inspected includes: a substrate 120, and a semiconductor layer 121 located on the surface of the substrate 120; the material of the semiconductor layer 121 is a compound or a single semiconductor material; the compound semiconductor material includes gallium arsenide, gallium nitride, and silicon carbide.

[0121] The nonlinear optical signal 312 can respond to the crystal structure defects in the compound semiconductor material, thereby achieving real-time monitoring of the crystal quality of the semiconductor layer 121 .

[0122] refer to Fig.12 , through the driving of the mechanical moving component, the carrier plate makes a linear motion in a direction parallel to the surface of the wafer to be detected, so that the incident point of the first annular incident light moves between the center and the edge of the carrier plate along the radial direction of the carrier plate; when driven by the mechanical moving component, the carrier plate is driven to rotate along the central axis of the carrier plate by the rotating device to obtain a scanning trajectory diagram of the first annular incident light 310. Fig.12The straight arrow in a represents the translation trajectory of the first annular incident light 310, and the curved arrow represents the rotation direction of the wafer carrier 100. The first annular incident light 310 scans back and forth between the center of the carrier plate and the edge of the carrier plate along the translation trajectory. Fig.12 b. The wafer carrier 100 is driven to rotate along the central axis by the rotating device to obtain a spiral scanning trajectory diagram of the first annular incident light 310 extending from the center to the edge of the carrier plate on the surface of the wafer to be inspected.

[0123] In this embodiment, the semiconductor layer is formed on the surface of the substrate by an epitaxial process. When the epitaxial process causes a crystal structure defect in the semiconductor layer, the crystal structure defect is coupled with the nonlinear optical signal 312, so that the nonlinear optical signal 312 can characterize the lattice defect or the crystal uniformity defect. The crystal structure defect includes a lattice defect or a crystal uniformity defect, and the crystal uniformity defect refers to a defect where the orderly arrangement of the lattice is distorted.

[0124] Combined with reference Figure 6 and Figure 1 , obtaining first defect information of the wafer 101 to be inspected according to the nonlinear optical signal 312.

[0125] In this embodiment, if Figure 2 As shown, the wafer 101 to be inspected includes: a substrate 110, and a dielectric layer 111 located on the surface of the substrate 110; the first defect information includes interface electrical property defects at the interface between the substrate and the dielectric layer; the interface electrical property defects include: interface state charge potential well defects, dielectric layer inherent charge distribution and defects, and substrate semiconductor doping concentration.

[0126] In another embodiment, if Figure 3 As shown, the wafer 101 to be inspected includes: a substrate 120, and a semiconductor layer 121 located on the surface of the substrate 120; the first defect information includes: crystal structure defects, internal stress distribution of the semiconductor layer, and epitaxial thickness of the semiconductor layer.

[0127] In addition to generating the first reflected light 311 on the surface of the wafer 101 to be inspected, the first annular incident light 310 also generates additional reflected light 314; the inspection method further includes: obtaining an additional optical signal 315 from the additional reflected light 314, and obtaining second defect information according to the additional optical signal 315. The second defect information is complementary to the first defect information, so that the inspection result is more comprehensive.

[0128] In this embodiment, the additional optical signal 315 and the nonlinear optical signal 312 are both reflected from the first annular incident light 310 provided by the first light source 201 .

[0129] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A semiconductor testing device, characterized in that: include: A wafer carrying device, used for carrying the wafer to be tested; An incident light system, emitting a first incident light; a beam shaping system, which shapes the first incident light into a first annular incident light, wherein the first annular incident light is reflected by the wafer to be inspected to form a first reflected light; An optical signal sorting system, used for sorting out a nonlinear optical signal from the first reflected light; A control system, used for acquiring first defect information of the wafer to be inspected according to the nonlinear optical signal; A main signal acquisition system, used for acquiring the nonlinear optical signal and transmitting the nonlinear optical signal to the control system; The additional signal acquisition system is used to obtain an additional optical signal from the first reflected light and transmit the additional optical signal to the control system.

2. The semiconductor testing device according to claim 1, wherein: The beam shaping system includes: a first axicon, used for converging the first incident light to form a first converging light; and a second axicon, used for diverging the first converging light to form the first annular incident light.

3. The semiconductor testing device according to claim 1, wherein: Also included is a focusing unit, which includes a lens.

4. The semiconductor testing device according to claim 3, wherein: The lens further includes a through hole, which penetrates the lens along a central axis of the lens.

5. The semiconductor testing device according to claim 1, wherein: The nonlinear optical signal includes a second harmonic signal, a third harmonic signal, a sum frequency response signal and a difference frequency response signal.

6. The semiconductor testing device according to claim 1, wherein: Also includes: A wafer alignment and focusing system, the wafer alignment and focusing system comprising: an imaging unit, used to obtain imaging patterns at different positions on the surface of a wafer to be inspected; The sensor is used to obtain the position information of the wafer to be detected in a first direction, where the first direction is perpendicular to the surface of the wafer to be detected.

7. The semiconductor testing device according to claim 6, wherein: The control system includes: an imaging operation unit, used to obtain the position information of the wafer to be inspected according to the imaging patterns at different positions on the surface of the wafer to be inspected; a first position control unit, used to move the wafer carrier along a direction parallel to a reference plane according to the position information, so as to realize the alignment of the first annular incident light on the surface of the wafer to be inspected, and the reference plane is parallel to the surface of the wafer to be inspected.

8. The semiconductor testing device according to claim 6, wherein: The control system comprises: a second position control unit, which is used to move the wafer carrying device according to the position information in the first direction, so as to achieve focusing of the first annular incident light on the surface of the wafer to be detected.

9. The semiconductor testing device according to claim 1, wherein: The incident light system includes: a first light source, used to emit a first initial incident light; a first incident light modulation unit, used to modulate the first initial incident light to form a first initial modulated incident light; and a spectrometer, used to form the first incident light emitted to the wafer to be inspected through the first initial modulated incident light.

10. The semiconductor testing device according to claim 9, wherein: The first light source includes a laser emitter.

11. The semiconductor testing device according to claim 1, wherein: Also includes: Optical collimation unit: used for collimating the first reflected light, and the collimated first reflected light is incident on the optical signal sorting system.

12. The semiconductor testing device according to claim 9, wherein: Also includes: Optical collimation unit: used for collimating the first reflected light. The collimated first reflected light passes through the beam shaping system and the beam splitter respectively and then enters the optical signal sorting system.

13. The semiconductor testing device according to claim 1, wherein: The optical signal sorting system comprises: an optical filter for passing a portion of the first reflected light having a preset wavelength range to form a first transition optical signal; and a polarizer for passing the first transition optical signal having preset polarization parameters to form the nonlinear optical signal.

14. The semiconductor testing device according to claim 1, wherein: The optical signal sorting system includes: a polarizer for passing a portion of the first reflected light with preset polarization parameters to form a second transition optical signal; and a filter for passing the second transition optical signal with a preset wavelength range to form the nonlinear optical signal.

15. The semiconductor testing device according to claim 1, wherein: The wafer carrying device includes: a carrying plate for carrying the wafer to be tested; a fixing device arranged on the carrying plate for fixing the wafer to be tested on the surface of the carrying plate; and a mechanical moving component for driving the carrying plate to move along a surface parallel to the wafer to be tested.

16. The semiconductor testing device according to claim 15, wherein: The wafer carrier device further includes: a rotating device, which is used to drive the carrier plate to rotate along the central axis of the carrier plate.

17. The semiconductor testing device according to claim 15, wherein: The fixing device is a vacuum suction cup or a buckle fixed to the edge of the carrying plate.

18. A semiconductor device with a process chamber, characterized in that: include: A process chamber, wherein the process chamber has a process window; According to any one of claims 1 to 17, the incident light system, the beam shaping system, the optical signal sorting system and the control system are located outside the process chamber, and the first annular incident light is vertically incident on the wafer to be inspected through the process window.

19. A detection method using the semiconductor detection device according to any one of claims 1 to 17, characterized in that: include: Provide wafers to be inspected; emitting a first incident light; shaping the first incident light into a first annular incident light, wherein the first annular incident light is reflected by the wafer to be inspected to form a first reflected light; Acquire the first reflected light, and sort out a nonlinear optical signal from the first reflected light; First defect information of the wafer to be inspected is acquired according to the nonlinear optical signal.

20. The detection method according to claim 19, characterized in that The wafer to be inspected includes: a substrate and a dielectric layer located on the surface of the substrate.

21. The detection method according to claim 20, characterized in that: The first defect information includes interface electrical property defects at the interface between the substrate and the dielectric layer; the interface electrical property defects include: interface state charge potential well defects, dielectric layer inherent charge distribution and defects, and substrate semiconductor doping concentration.

22. The detection method according to claim 19, characterized in that: The wafer to be inspected comprises: a substrate and a semiconductor layer located on the surface of the substrate; the material of the semiconductor layer is a compound semiconductor material or a single-element semiconductor material.

23. The detection method according to claim 22, characterized in that: The compound semiconductor material includes gallium arsenide, gallium nitride or silicon carbide; the formation process of the semiconductor layer includes an epitaxial process.

24. The detection method according to claim 22, characterized in that: The first defect information includes: crystal structure defects, stress distribution inside the semiconductor layer, and epitaxial thickness of the semiconductor layer.

25. The detection method according to claim 22, characterized in that: The wafer carrying device includes: a carrying plate for carrying the wafer to be detected; a fixing device arranged on the carrying plate for fixing the wafer to be detected on the surface of the carrying plate; a mechanical moving component for driving the carrying plate to move along a surface parallel to the wafer to be detected; a rotating device for driving the carrying plate to rotate along the central axis; the detection method includes: driving the mechanical moving component to make the carrying plate move in a straight line in a direction parallel to the surface of the wafer to be detected, so that the incident point of the first annular incident light moves between the center and the edge of the carrying plate along the radial direction of the carrying plate; when driven by the mechanical moving component, the carrying plate is driven to rotate along the central axis of the carrying plate by the rotating device.

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