The present invention relates to corona charge deposition systems that use High Voltage (HV) amplifiers for precisely controlling corona charge deposition. Some implementations, provide a corona charge deposition system that uses multiple voltage sources to maintain specified voltages applied on several electrodes to precisely control the corona current required to deposit a desired amount of charge on a sample. The HV amplifiers are able to source and sink currents to maintain stable voltages applied on control electrodes in the presence of a higher voltage applied on a needle electrode. The proposed apparatus and method of monitoring multiple signals, controlling multiple voltages, and predicting charge profile deposited on a sample can precisely control charge deposition processes.
Apparatus is described for performing simultaneous corona deposition and surface electric field induced second harmonic (EFISH) measurements. Example designs include systems including corona guns having a focus tube for deposition of corona charge with windows therein for passage of a laser beam incident on and reflected from a sample surface. Various designs may also employ masks proximal the distal end of the focusing tube and/or proximal the sample surface. In some implementations, the apparatus is used to make ungrounded and therefore non-invasive measurements, for example, on dielectric on semiconductor such as, e.g., interface state density (Dit), flatband voltage (Vfb) and/or lifetime measurements.
Methods are disclosed for improving one or more of jitter/timing, signal-to-noise ratio, signal integrity, stability, and repeatability of generation and measurement of Second Harmonic Generation (SHG) signals generated by a sample upon illumination by a light beam. The method may use precision hardware to control the generation of SHG signal and synchronize it with the optical detection process to improve the reliability and accuracy of measured SHG signals. A precise measurement of the initial SHG signal (Io) involves accurate temporal alignment between optical excitation and detection of the resulting SHG signal. Various disclosed systems and methods use high-speed Pockels Cell (PC) for controlling incident light, and precision electronics for synchronization.
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
4.
METHOD AND APPARATUS FOR SEPARATION OF THE SECOND HARMONIC GENERATION COMPONENTS, THROUGH VARIATION IN THE INPUT PROBING LASER POLARIZATION
When a high intensity Second Harmonic Signal (SHG) probing laser is incident on a wafer surface under test, the SHG response is generally the combination of a few components: contributions from interfaces between material types (e.g., the semiconductor/dielectric interface), contributions from material non-centrosymmetric bulk regions, and/or contribution from the electric field near material interfaces. To separate the various components, SHG measurements can be performed as a function of the input probing laser polarization. Described herein are methods of acquiring an SHG versus polarization curve in a manner to expedite the measurement time.
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G02F 1/37 - Non-linear optics for second-harmonic generation
Systems and methods are disclosed for using second-harmonic generation of light to monitor the manufacturing process for changes that can affect the performance or yield of produced devices and/or determining critical dimensions of the produced device.
G01B 11/02 - Measuring arrangements characterised by the use of optical techniques for measuring length, width, or thickness
H01L 21/66 - Testing or measuring during manufacture or treatment
6.
METHOD AND APPARATUS FOR NON-INVASIVE SEMICONDUCTOR TECHNIQUE FOR MEASURING DIELECTRIC/SEMICONDUCTOR INTERFACE TRAP DENSITY USING SCANNING ELECTRON MICROSCOPE CHARGING
A non-invasive semiconductor technique for measuring dielectric/semiconductor interface trap density can be performed by charging the dielectric by creating charges on the top surface of the dielectric layer over the wafer using Scanning Electron Microscope (SEM) charging. This charging can induce an accumulated, a depleted and/or an inverted semiconductor surface. The states of the semiconductor surface can subsequently be measured, identified, and/or quantified using Electric Field Induced Second Harmonic generation (EFISH). From the measured/acquired EFISH versus SEM charge curve, the interface state density (Dit) can be extracted. A large working distance provides the ability to create charge and measure the Second Harmonic Generation (SHG) at the same semiconductor surface spot without the needing to move the wafer.
H01J 37/02 - Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof - Details
H01J 37/22 - Optical or photographic arrangements associated with the tube
H01J 37/244 - Detectors; Associated components or circuits therefor
H01J 37/28 - Electron or ion microscopes; Electron- or ion-diffraction tubes with scanning beams
7.
Surface Sensing Systems and Methods for Imaging a Scanned Surface of a Sample Via Sum-Frequency Vibrational Spectroscopy
Surface sensing methods for imaging a scanned surface of a sample via sum-frequency vibrational spectroscopy are disclosed herein. The methods include exposing a sampled location of the scanned surface to a visible light beam and exposing the sampled location to a tunable infrared beam such that the tunable infrared beam is at least partially coincident with the visible light beam. The methods also include varying a frequency of the tunable infrared beam an inducing optical resonance within an imaged structure that extends at least partially within the sampled location. The methods further include receiving at least a portion of an emitted light beam from the sampled location and scanning the visible light beam and the runnable infrared beam across the scanned portion of the scanned surface. The methods also include generating an image of the scanned portion of the scanned surface based upon the receiving and the scanning.
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
Surface sensing methods for imaging a scanned surface of a sample via sum-frequency vibrational spectroscopy are disclosed herein. The methods include exposing a sampled location of the scanned surface to a visible light beam and exposing the sampled location to a tunable infrared beam such that the tunable infrared beam is at least partially coincident with the visible light beam. The methods also include varying a frequency of the tunable infrared beam an inducing optical resonance within an imaged structure that extends at least partially within the sampled location. The methods further include receiving at least a portion of an emitted light beam from the sampled location and scanning the visible light beam and the runnable infrared beam across the scanned portion of the scanned surface. The methods also include generating an image of the scanned portion of the scanned surface based upon the receiving and the scanning.
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01B 11/24 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
G01J 3/10 - Arrangements of light sources specially adapted for spectrometry or colorimetry
Various approaches can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation. Decay constants can be measured to provide information regarding the sample. Additionally, electric and/or magnetic field biases can be applied to the sample to provide additional information.
G01R 31/26 - Testing of individual semiconductor devices
G01N 27/00 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
H01L 21/66 - Testing or measuring during manufacture or treatment
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01R 31/308 - Contactless testing using non-ionising electromagnetic radiation, e.g. optical radiation
G01R 31/28 - Testing of electronic circuits, e.g. by signal tracer
10.
SECOND-HARMONIC GENERATION FOR CRITICAL DIMENSIONAL METROLOGY
Systems and methods are disclosed for using second-harmonic generation of light to monitor the manufacturing process for changes that can affect the performance or yield of produced devices and/or determining critical dimensions of the produced device.
Semiconductor metrology systems based on directing radiation on a wafer, detecting second harmonic generated (SHG) radiation from the wafer and correlating the second harmonic generated (SHG) signal to one or more electrical properties of the wafer are disclosed. The disclosure also includes parsing the SHG signal to remove contribution to the SHG signal from one or more material properties of the sample such as thickness. Systems and methods described herein include machine learning methodologies to automatically classify obtained SHG signal
G01N 21/95 - Investigating the presence of flaws, defects or contamination characterised by the material or shape of the object to be examined
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
H01L 21/66 - Testing or measuring during manufacture or treatment
12.
Pump and probe type second harmonic generation metrology
Various approaches to can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation.
G01N 21/95 - Investigating the presence of flaws, defects or contamination characterised by the material or shape of the object to be examined
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01R 29/24 - Arrangements for measuring quantities of charge
G01N 21/88 - Investigating the presence of flaws, defects or contamination
G01N 21/94 - Investigating contamination, e.g. dust
Surface sensing methods for imaging a scanned surface of a sample via sum-frequency vibrational spectroscopy are disclosed herein. The methods include exposing a sampled location of the scanned surface to a visible light beam and exposing the sampled location to a tunable infrared beam such that the tunable infrared beam is at least partially coincident with the visible light beam. The methods also include varying a frequency of the tunable infrared beam an inducing optical resonance within an imaged structure that extends at least partially within the sampled location. The methods further include receiving at least a portion of an emitted light beam from the sampled location and scanning the visible light beam and the runnable infrared beam across the scanned portion of the scanned surface. The methods also include generating an image of the scanned portion of the scanned surface based upon the receiving and the scanning.
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
Various approaches to can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation.
G01R 29/24 - Arrangements for measuring quantities of charge
G01R 31/308 - Contactless testing using non-ionising electromagnetic radiation, e.g. optical radiation
G01R 31/28 - Testing of electronic circuits, e.g. by signal tracer
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01N 21/88 - Investigating the presence of flaws, defects or contamination
G01N 21/95 - Investigating the presence of flaws, defects or contamination characterised by the material or shape of the object to be examined
G01N 21/94 - Investigating contamination, e.g. dust
Semiconductor metrology systems based on directing radiation on a wafer, detecting second harmonic generated (SHG) radiation from the wafer and correlating the second harmonic generated (SHG) signal to one or more electrical properties of the wafer are disclosed. The disclosure also includes parsing the SHG signal to remove contribution to the SHG signal from one or more material properties of the sample such as thickness. Systems and methods described herein include machine learning methodologies to automatically classify obtained SHG signal.
G01N 21/95 - Investigating the presence of flaws, defects or contamination characterised by the material or shape of the object to be examined
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
H01L 21/66 - Testing or measuring during manufacture or treatment
Various approaches can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation. Decay constants can be measured to provide information regarding the sample. Additionally, electric and/or magnetic field biases can be applied to the sample to provide additional information.
G01N 21/88 - Investigating the presence of flaws, defects or contamination
G01N 21/95 - Investigating the presence of flaws, defects or contamination characterised by the material or shape of the object to be examined
G01N 21/94 - Investigating contamination, e.g. dust
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01R 29/24 - Arrangements for measuring quantities of charge
Various approaches can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation. Decay constants can be measured to provide information regarding the sample. Additionally, electric and/or magnetic field biases can be applied to the sample to provide additional information.
G01R 29/24 - Arrangements for measuring quantities of charge
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01N 21/88 - Investigating the presence of flaws, defects or contamination
G01N 21/94 - Investigating contamination, e.g. dust
G01N 21/95 - Investigating the presence of flaws, defects or contamination characterised by the material or shape of the object to be examined
G01N 27/00 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
H01L 21/66 - Testing or measuring during manufacture or treatment
G01R 31/26 - Testing of individual semiconductor devices
Second Harmonic Generation (SHG) can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. In some instances, SHG is used to evaluate an interfacial region such as between metal and oxide. Various parameters such as input polarization, output polarization, and azimuthal angle of incident beam, may affect the SHG signal. Accordingly, such parameters are varied for different types of patterns on the wafer. SHG metrology on various test structures may also assist in characterizing a sample.
Various approaches can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation while other utilize four wave-mixing or multi-wave mixing. Corona discharge may be applied to the sample to provide additional information. Some approaches involve determining current flow from a sample illuminated with radiation.
G01R 29/24 - Arrangements for measuring quantities of charge
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01R 31/26 - Testing of individual semiconductor devices
G01R 31/28 - Testing of electronic circuits, e.g. by signal tracer
G01R 31/308 - Contactless testing using non-ionising electromagnetic radiation, e.g. optical radiation
20.
Surface sensing systems and methods for imaging a scanned surface of a sample via sum-frequency vibrational spectroscopy
Surface sensing methods for imaging a scanned surface of a sample via sum-frequency vibrational spectroscopy are disclosed herein. The methods include exposing a sampled location of the scanned surface to a visible light beam and exposing the sampled location to a tunable infrared beam such that the tunable infrared beam is at least partially coincident with the visible light beam. The methods also include varying a frequency of the tunable infrared beam an inducing optical resonance within an imaged structure that extends at least partially within the sampled location. The methods further include receiving at least a portion of an emitted light beam from the sampled location and scanning the visible light beam and the runnable infrared beam across the scanned portion of the scanned surface. The methods also include generating an image of the scanned portion of the scanned surface based upon the receiving and the scanning.
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01B 11/24 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
G01J 3/10 - Arrangements of light sources specially adapted for spectrometry or colorimetry
Various approaches to can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation.
G01R 31/26 - Testing of individual semiconductor devices
G01N 27/00 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
H01L 21/66 - Testing or measuring during manufacture or treatment
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01R 31/308 - Contactless testing using non-ionising electromagnetic radiation, e.g. optical radiation
G01R 31/28 - Testing of electronic circuits, e.g. by signal tracer
Various approaches can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation. Decay constants can be measured to provide information regarding the sample. Additionally, electric and/or magnetic field biases can be applied to the sample to provide additional information.
G01N 27/00 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
H01L 21/66 - Testing or measuring during manufacture or treatment
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
G01R 31/308 - Contactless testing using non-ionising electromagnetic radiation, e.g. optical radiation
G01R 31/28 - Testing of electronic circuits, e.g. by signal tracer
Various approaches can be used to interrogate a surface such as a surface of a layered semiconductor structure on a semiconductor wafer. Certain approaches employ Second Harmonic Generation and in some cases may utilize pump and probe radiation. Other approaches involve determining current flow from a sample illuminated with radiation. Decay constants can be measured to provide information regarding the sample. Additionally, electric and/or magnetic field biases can be applied to the sample to provide additional information.
G01R 31/26 - Testing of individual semiconductor devices
G01N 27/00 - Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
H01L 21/66 - Testing or measuring during manufacture or treatment
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
24.
Surface sensing systems and methods for imaging a scanned surface of a sample via sum-frequency vibrational spectroscopy
Surface sensing systems and methods for imaging a scanned surface of a sample via sum-frequency vibrational spectroscopy are disclosed herein. The systems include a sample holder, a visible light source configured to direct a visible light beam incident upon a sampled location of the scanned surface and a tunable IR source configured to direct a tunable IR beam coincident with the visible light beam upon the sampled location. The systems also include a scanning structure configured to scan the visible light beam and the tunable IR beam across the scanned surface, and a light filter configured to receive an emitted beam from the scanned surface and to filter the emitted beam to generate a filtered light beam. The systems further include a light detection system configured to receive the filtered light beam, and an alignment structure. The methods include methods of operating the systems.
G01N 21/63 - Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
Semiconductor metrology systems based on directing radiation on a wafer, detecting second harmonic generated (SHG) radiation from the wafer and correlating the second harmonic generated (SHG) signal to one or more electrical properties of the wafer are disclosed. The disclosure also includes parsing the SHG signal to remove contribution to the SHG signal from one or more material properties of the sample such as thickness. Systems and methods described herein include machine learning methodologies to automatically classify obtained SHG signal data from the wafer based on an electrical property of the wafer.
patents
