摘要:
The present invention resides in method and apparatus for measuring a minute displacement, comprising applying a light of a first wavelength at a predetermined angle to a diffraction grating formed on an object whose position is to be detected, subjecting each of the resulting diffracted light and regular reflected light and a light of a second wavelength different from the first wavelength to heterodyne interference with each other to generate a measurement signal and a reference signal, and measuring a phase difference between the measurement signal and the reference signal to thereby determine a minute displacement of the object.
摘要:
A novel exposure system includes a reduced-projection lens optimized for a predetermined single exposure wavelength and a chromatic aberration correction system for TTL (Through The Lens) alignment with broadband light. The correction system includes a holographic lens which dispersion has a negative number in contrast to a conventional glass lens which has a positive dispersion number. By employing a holographic lens, the total optical length of an alignment system can be made short enough to avoid the necessity of installing a mirror therein, thus realizing a highly accurate alignment system.
摘要:
An illuminating method and an illuminating apparatus for use in combination, for example, with an exposure apparatus. The illuminating apparatus comprises amplitude distribution control means for converting the intensity distribution of a light beam emitted by a highly directional light source into a substantially linear intensity distribution, beam splitting means for splitting the light beam into a plurality of component beams, and superposing means for superposing the component beams in a desired area on an object, such as a reticle, in an uniform illuminance distribution.
摘要:
A method and a system for pattern detection are disclosed in which a laser beam high in directivity is emitted from a laser beam source, the laser beam emitted from the laser beam source is irradiated on an uneven pattern to be detected on an object, the light component of a frequency corresponding to the cut-off frequency of an objective lens is removed from the light reflected from the object when an image of the pattern on the object is formed through an objective lens, the optical image thus formed is received by a photoelectric converting device for producing a signal waveform representing the pattern free of a signal of the frequency corresponding to the cut-off frequency, and the pattern is detected from a signal produced from the photoelectric converting device.
摘要:
A method and apparatus is disclosed for detecting a pattern image of each of a plurality of patterns on the surface of an object. Light emitted from either a light source including a wide wavelength or a light source including a plurality of monowavelengths is applied to the object. The object includes a layered structure having a plurality of layers, wherein at least a part of an uppermost layer of the object is optically transparent. Spectral illumination intensity characteristics of the light emitted from the light source is varied, depending on information about both the layered structure of the object, and a material of the object to obtain a desired spectral illumination intensity, and a pattern image of each of patterns is detected as either a one-dimensional or a two-dimensional image based on light reflected from the object.
摘要:
The invention relates to a semiconductor exposing system for projecting a pattern of a mask onto a semiconductor wafer and, more particularly, to such a system having an apparatus for correcting an influence on the resolution by a fluctuation in wavelength of a laser light source. The system of the invention comprises: a laser light source; an optical projecting system for projecting a laser beam emitted from the laser light source onto the semiconductor wafer through the mask; and an apparatus for receiving a part of the laser beam emitted from the laser light source, for detecting the wavelength fluctuation, and for correcting the position and magnification of the optical projecting system in accordance with the wavelength fluctuation value or an apparatus for correcting the refractive index of the optical projecting system.
摘要:
A wafer is aligned by using an alignment light having a longer wavelength than an exposure light. Exposure and alignment are effected through a common reduction lens. A wavefront aberration caused by the use of the long wavelength alignment light is compensated by a hologram. Thus, an alignment precision is improved without exposing a resist layer to a light.
摘要:
An illumination apparatus is disclosed which is suitable for use in a projection/exposure system for projecting an image of a circuit pattern of a reticle on a semiconductor wafer through a projection lens. The illumination apparatus includes an excimer laser for emitting a pulsed laser beam, an optical system for illuminating the reticle with a plurality of laser pulses emitted from the excimer laser so that laser pulses having passed through the reticle impinge on the semiconductor wafer in different directions through the projection lens, and a light intensity control device for controlling the light intensity of each of the laser pulses so that the laser pulses equally contribute to the reaction of a light sensitive material which is provided on the semiconductor wafer, with light.
摘要:
Disclosed is a distance measuring device using an optical comb. In order for the absolute distance to an object to be measured which has a surface with low reflection ratio or a scattering surface and is approximately 10 m apart, to be easily measured with accuracy of 0.1 mm or more using an optical and contactless method, the distance measuring device which measures the distance to the object to be measured is configured such that the distance to the object to be measured is measured by comparing the phase of the beat signal between a light source and a plurality of CW lasers which are reflected or scattered by the object with the phase of the beat signal between the light source and a plurality of CW lasers prior to being irradiated onto the object.
摘要:
In a displacement measurement apparatus using light interference, a probe light path is spatially separated from a reference light path. Therefore, when a temperature or refractive index distribution by a fluctuation of air or the like, or a mechanical vibration is generated, an optical path difference fluctuates between both of the optical paths, and a measurement error is generated. In the solution, an optical axis of probe light is brought close to that of reference light by a distance which is not influenced by any disturbance, a sample is irradiated with the probe light, a reference surface is irradiated with the reference light, reflected light beams are allowed to interfere with each other, and a displacement of the sample is obtained from the resultant interference light to thereby prevent the measurement error from being generated by the fluctuation of the optical path difference.