Disclosed is a laser-driven photon source comprising drive optics which focus drive radiation so as to maintain a plasma. The point spread function of the drive optics has a point spread function (75) which is configured such that a spectral position of a peak output wavelength of a black body portion of output radiation emitted by said plasma within a desired wavelength band.

The present disclosure provides a method for manufacturing a semiconductor structure. The method includes forming a photo-sensitive layer on a first surface of a semiconductor substrate. The photo-sensitive layer has a top surface. The method also includes obtaining a first profile of the first surface of the semiconductor substrate, and obtaining a second profile of the top surface of the photo-sensitive layer. The method also includes calculating a vertical displacement profile of the semiconductor substrate according to the first profile and the second profile. An apparatus for manufacturing a semiconductor structure is also disclosed.

A process for inspecting an EUV mask blank capable of distinguishing phase defects and amplitude defects and capable of detecting small amplitude defects, a process for producing an EUV mask blank using the inspection process, and an EUV mask blank obtainable by such a process. A process for inspecting a reflective mask blank for EUV lithography having a multilayer reflective film and an absorber layer. The process includes a first step of detecting in-plane defects in the multilayer reflective film by applying EUV light to the surface of the multilayer reflective film, a second step of detecting in-plane defects from the absorber layer by applying light having a wavelength of from 150 to 600 nm to the surface of the absorber layer, and a step of distinguishing phase defects and amplitude defects in the reflective mask blank by comparison between the first and second in-plane defect data.

A method of defect inspection for a photomask is provided. According to the method, a light transmittance correction is performed to reduce a light transmittance of a calibration key pattern region of a photomask including a field region and the calibration key pattern region to the light transmittance of the field region. Light calibration is performed using the calibration key pattern region having corrected light transmittance. Defect inspection for the field region is performed by applying a result of the light calibration.

The present disclosure provides a method including providing a first image and a second image. The first image is of a substrate having a defect and the second image is of a reference substrate. A difference between the first image and the second image is determined. A simulation model is used to generate a simulation curve corresponding to the difference and the substrate dispositioned based on the simulation curve. In another embodiment, the scan of a substrate is used to generate a statistical process control chart.

When a reticle is first used, the reticle is loaded in a projection exposure device and measured by either oblique measurement and random measurement, thereby avoiding the fear of uneven sampling and determining the reticle transmittance of the entire reticle as the parent population, without increasing the sampling count. The same effect can be obtained by making the measurement spot size, which is fixed in general, variable and by changing the angle of incidence in relation to the measurement spot size.

Laser and inspection systems that generate laser output light at sub-200 nm wavelengths using fundamental light at approximately 1064 nm. A second harmonic generator module generates second harmonic light directed to both an optical parametric (OP) module, which generates down-converted signal (idler light), and to a fifth harmonic generator module, which generates fifth harmonic light. The OP module includes an optical parametric oscillator that is configured to generate the idler signal at approximately 0.5 times the fundamental frequency. The idler light and fifth harmonic light are then mixed by a frequency mixing module to generate the laser output light having an output frequency equal to approximately 5.5 times the fundamental frequency.

An apparatus and method are disclosed for actinic inspection of semiconductor masks intended for extended ultraviolet (EUV) lithography, or similar objects, with feature sizes less than 100 nm. The approach uses a coherent light source with wavelength less than 120 nm. Inside a vacuum system, an optical system directs the light to an object, i.e., the mask or mask blank, and directs the resulting reflected or transmitted light to an imaging sensor. A computational system processes the imaging sensor data to generate phase and amplitude images of the object. The preferred imaging modality, a form of digital holography, produces images of buried structures and phase objects, as well as amplitude or reflectance images, with nanometer resolution less than or equal to the feature size of the mask.

An inspection system including an optical system (optics) to direct light from an illumination source to a sample, and to direct light reflected/scattered from the sample to one or more image sensors. At least one image sensor of the system is formed on a semiconductor membrane including an epitaxial layer having opposing surfaces, with circuit elements formed on one surface of the epitaxial layer, and a pure boron layer on the other surface of the epitaxial layer. The image sensor may be fabricated using CCD (charge coupled device) or CMOS (complementary metal oxide semiconductor) technology. The image sensor may be a two-dimensional area sensor, or a one-dimensional array sensor. The image sensor can be included in an electron-bombarded image sensor and/or in an inspection system.

The defect size of a photomask blank is evaluated. An inspection-target photomask blank is irradiated with inspection light and reflected light of the region of the inspection-target photomask blank irradiated with the inspection light is collected through an objective lens of an inspection optical system as a magnified image of the region. Then, an intensity change part in the light intensity distribution profile of the magnified image is identified. Next, a difference in the light intensity of the intensity change part is obtained and the width of the intensity change part is obtained as the apparent width of the defect. Then, the width of the defect is calculated on the basis of a predetermined conversion expression showing the relationship among the difference in the light intensity, the apparent width of the defect, and the actual width of the defect, and the width of the defect is estimated.