Abstract: Optical metrology is used to calibrate the plane-of-incidence (POI) azimuth error by determining and correcting an azimuth angle offset. The azimuth angle offset may be determined by measuring at least a partial Mueller matrix from a calibration grating on a sample held on a stage for a plurality of POI azimuth angles. An axis of symmetry is determined for a curve describing a value of a Mueller matrix element with respect to POI azimuth angle, for each desired wavelength and each desired Mueller matrix element. The axis of symmetry may then be used to determine the azimuth angle offset, e.g., by determining a mean, median or average of all, or a filtered subset, of the axes of symmetry. If desired, an axis of symmetry may be determined for data sets other than Mueller matrix elements, such as Fourier coefficients of measured signals.

Abstract: An atomizing device of an electronic cigarette is provided. The atomizing device includes a screw sleeve and an electrode ring fixed in the screw sleeve. The screw sleeve includes a glass fiber core, a heating coil winding around the glass fiber core and a heating coil support. Each of two ends of the heating coil is respectively connected to a silver coated bare electrical wire. The heating coil support has a central through hole and two side wall through holes. The bare electrical wires respectively extend through the side wall through holes which are exposed to two ends of the heating coil support, then respectively in contact with the screw sleeve and the electrode ring. An electronic cigarette having the atomizing device is also disclosed.

Abstract: A sample with at least a first structure and a second structure is measured and a first model and a second model of the sample are generated. The first model models the first structure as an independent variable and models the second structure. The second model of the sample models the second structure as an independent variable. The measurement, the first model and the second model together to determine at least one desired parameter of the sample. For example, the first structure may be on a first layer and the second structure may be on a second layer that is under the first layer, and the processing of the sample may at least partially remove the first layer, wherein the second model models the first layer as having a thickness of zero.

Abstract: A structure that is located adjacent to a measurement target on a substrate is used to convert incident radiation from an optical metrology device to be in-plane with the measurement target. The structure may be, e.g., a grating or photonic crystal, and may include a waveguide between the structure and the measurement target. The in-plane light interacts with the measurement target and is reflected back to the structure, which converts the in-plane light to out-of-plane light that is received by the optical metrology device. The optical metrology device then uses the information from the received light to determine one or more desired parameters of the measurement target. Additional structures may be used to receive light that is transmitted through or scattered by the measurement target if desired.

Abstract: A sample with at least a first structure and a second structure is measured and a first model and a second model of the sample are generated. The first model models the first structure as an independent variable and models the second structure. The second model of the sample models the second structure as an independent variable. The measurement, the first model and the second model together to determine at least one desired parameter of the sample. For example, the first structure may be on a first layer and the second structure may be on a second layer that is under the first layer, and the processing of the sample may at least partially remove the first layer, wherein the second model models the first layer as having a thickness of zero.

Abstract: A structure that is located adjacent to a measurement target on a substrate is used to convert incident radiation from an optical metrology device to be in-plane with the measurement target. The structure may be, e.g., a grating or photonic crystal, and may include a waveguide between the structure and the measurement target. The in-plane light interacts with the measurement target and is reflected back to the structure, which converts the in-plane light to out-of-plane light that is received by the optical metrology device. The optical metrology device then uses the information from the received light to determine one or more desired parameters of the measurement target. Additional structures may be used to receive light that is transmitted through or scattered by the measurement target if desired.

Abstract: A structure that is located adjacent to a measurement target on a substrate is used to convert incident radiation from an optical metrology device to be in-plane with the measurement target. The structure may be, e.g., a grating or photonic crystal, and may include a waveguide between the structure and the measurement target. The in-plane light interacts with the measurement target and is reflected back to the structure, which converts the in-plane light to out-of-plane light that is received by the optical metrology device. The optical metrology device then uses the information from the received light to determine one or more desired parameters of the measurement target. Additional structures may be used to receive light that is transmitted through or scattered by the measurement target if desired.

Abstract: A sample that is processed to remove a top layer, e.g., using chemical mechanical polishing or etching, is accurately measured using multiple models of the sample. The multiple models may be constrained based on a pre-processing measurement of the sample. By way of example, the multiple models of the sample may be linked in pairs, where one pair includes a model simulating the pre-processed sample and another model simulating the post-processed sample with a portion of the top layer remaining, i.e., under-processing. Another pair of linked models includes a model simulating the pre-processed sample and a model simulating the post-processing sample with the top layer removed, i.e., the correct amount of processing or over-processing. The underlying layers in the linked model pairs are constrained to have the same parameters. The modeling process may use a non-linear regression or libraries.

Abstract: A structure that is located adjacent to a measurement target on a substrate is used to convert incident radiation from an optical metrology device to be in-plane with the measurement target. The structure may be, e.g., a grating or photonic crystal, and may include a waveguide between the structure and the measurement target. The in-plane light interacts with the measurement target and is reflected back to the structure, which converts the in-plane light to out-of-plane light that is received by the optical metrology device. The optical metrology device then uses the information from the received light to determine one or more desired parameters of the measurement target. Additional structures may be used to receive light that is transmitted through or scattered by the measurement target if desired.

Abstract: A sample that is processed to remove a top layer, e.g., using chemical mechanical polishing or etching, is accurately measured using multiple models of the sample. The multiple models may be constrained based on a pre-processing measurement of the sample. By way of example, the multiple models of the sample may be linked in pairs, where one pair includes a model simulating the pre-processed sample and another model simulating the post-processed sample with a portion of the top layer remaining, i.e., under-processing. Another pair of linked models includes a model simulating the pre-processed sample and a model simulating the post-processing sample with the top layer removed, i.e., the correct amount of processing or over-processing. The underlying layers in the linked model pairs are constrained to have the same parameters. The modeling process may use a non-linear regression or libraries.

Abstract: A metrology system performs optical metrology while holding a sample with an unknown focus offset. The measurements are corrected by fitting for the focus offset in a model regression analysis. Focus calibration is used to determine the optical response of the metrology device to the focus offset. The modeled data is adjusted based on the optical response to the focus offset and the model regression analysis fits for the focus offset as a variable parameter along with the sample characteristics that are to be measured. Once an adequate fit is determined, the values of the sample characteristics to be measured are reported. The adjusted modeled data may be stored in a library, or alternatively, modeled data may be adjusted in real-time.

Abstract: An improved fiber optic tap monitor has characteristics that are flatter over the wavelength range of interest. The tap monitor includes a filter that reflects a major fraction of the light from a first fiber to a second fiber. A photodetector located behind the filter detects the light transmitted by the filter. The reflectance spectrum of the filter is selected to compensate for nonuniformities in the detection response characteristic of the photodetector over the wavelength range of interest, so that the overall response of the tap monitor is relatively flat.