Optical to optical time and spatial resolution enhancements for improving characterization of secondary electron emission and control for etch-, electron-, and ion-beam devices
AssigneeAttofemto, Inc.
InventorPaul L. Pfaff
Life of this patent
Estimating the term…
Abstract
In decreasing the electron beam duration required for increased time resolution, the average beam current decreases, degrading measurement sensitivity and limiting practical systems to a time resolution of several hundred picoseconds. Optical non-invasive or non-destructive enhancements permits femto-second measurements and a new regime of internal device and process evaluation and quality control in integrated circuit (IC) manufacture, at every stage from the initial wafer to the point at which the wafer is diced into individual ICs.
Claims22
An optical image detection method for enhancing time and spatial resolution in internal integrated circuit testing in at least one phase of evaluation and manufacture, using a first infrared or optical imaging device that is sensitive to an incident electron or ion beam or X-ray beam or an illumination which stimulates a secondary electron emission or creates a photocurrent or changes in electric field or stresses within or acting upon the first imaging device, and a second infrared imaging device that is illuminated by light incident to the first imaging device which is reflected to the second imaging device which images optical changes in phase or polarization or amplitude or birefringence or intensity within the first imaging device, the method comprising:
- imposing an optical beam over the spatial area of stimulation of secondary electron emission from surface metallization by the incident electron or ion-beam or X-ray beam or an illumination optically modulating the optical beam;
- directing the optical beam incident to the area of stimulation of secondary electron or photon emission to the a first infrared or optical imaging device;
- and
- adjusting the duration or modulation or attributes of the incident optical beam relative to the feature or duration or intensity or movement or target area of the electron or ion beam or X-ray beam or an ultraviolet illumination to enhance the sampling time resolution or spatial attributes of the feature shaped or determined by the electron or ion-beam or ultraviolet illumination or the effects thereof, and illuminating the second infrared imaging device by light incident to the first imaging device which is reflected to the second imaging device to image optical changes in phase or polarization or amplitude or birefringence or intensity within the first imaging device.
An optical image detection method for enhancing time and spatial resolution in internal integrated circuit testing in at least one phase of evaluation and manufacture, using a first infrared or optical imaging device that is sensitive to an incident electron or ion beam or X-ray beam or an ultraviolet illumination which stimulates a secondary electron emission or creates a photocurrent or changes in electric field or stresses within or acting upon the first imaging device, and a second infrared imaging device that is illuminated by light incident to the first imaging device which is reflected to the second imaging device which images optical changes in phase or polarization or amplitude or birefringence or intensity or optical interference within the first imaging device, the method comprising:
- splitting and adjusting the first optical reference beam incident to the first infrared or optical imaging device,
- imposing the first object optical beam over the spatial area of stimulation of secondary electron emission from surface metallization by the incident electron or ion-beam or X-ray beam or an illumination optically modulating the optical beam and adjusting the reflection or transmission of reference beam to interfere with the first beam incident to the first infrared or optical imaging device;
- directing the optical beam incident to the target area of stimulation of secondary electron or photon emission to interfere with beam incident to the a first infrared or optical imaging device;
- and
- adjusting the duration or modulation or attributes of the incident optical beam relative to the feature or duration or intensity or movement or target area of the electron or ion beam or X-ray beam or an ultraviolet illumination to enhance the sampling time resolution or spatial attributes of the feature shaped or determined by the electron or ion-beam or ultraviolet illumination or the effects thereof, and illuminating the second infrared imaging device by light incident to the first imaging device which is reflected to the second imaging device to image optical changes in phase or polarization or amplitude or birefringence or intensity or optical interference within the first imaging device.
An optical image detection method for enhancing time and spatial resolution in internal integrated circuit testing in at least one phase of evaluation and manufacture, using a first infrared or optical imaging device that is sensitive to an incident electron or ion beam or X-ray beam or an ultraviolet illumination which stimulates a secondary electron emission or creates a photocurrent or changes in electric field or stresses within or acting upon the first imaging device, and a second infrared imaging device that is illuminated by a second reference light beam incident to the first imaging device which is reflected to interfere with the second object beam to the second imaging device which images optical changes in phase or polarization or amplitude or birefringence or intensity or optical interference within the first imaging device, the method comprising;
- imposing the first object optical beam over the spatial area of stimulation of secondary electron emission from surface metallization by the incident electron or ion-beam or X-ray beam or an illumination optically modulating the optical beam and adjusting the reflection or transmission of reference beam to interfere with the first beam incident to the first infrared or optical imaging device;
- splitting and adjusting the second optical beam into a reference beam incident to the second infrared or optical imaging device;
- directing the second optical beam into an object beam incident to interfere with the second beam incident to the first infrared or optical imaging device;
- and
- adjusting the duration or modulation or attributes of the first incident optical beam relative to the feature or duration or intensity or movement or target area of the electron or ion beam or X-ray beam or an ultraviolet illumination to enhance the sampling time resolution or spatial attributes of the feature shaped or determined by the electron or ion-beam or ultraviolet illumination or the effects thereof, and illuminating the second infrared imaging device by a second reference light beam incident to the first imaging device which is reflected to interfere with the second object beam to the second imaging device which images optical changes in phase or polarization or amplitude or birefringence or intensity or optical interference within the first imaging device.
Dependencies are inferred from the claim text.