Alignment apparatus

An alignment apparatus for an exposure apparatus for transferring a pattern on a mask onto a photosensitive substrate, comprising:

• a beam radiation system for radiating two first beams unto a diffraction grating-like mask mark formed on said mask, and radiating two second beams, which are discrete from the first beams on an incident side of said mask, onto a diffraction grating-like substrate mark formed on said photosensitive substrate;
• said mask having a region transparent to the two second beams at an adjacent position in a direction perpendicular to a grating period direction of said mask mark or a position neighboring said mask mark;
• said beam radiation system including:
• a first beam output system for forming the two first beams, which cross at a predetermined angle, so as to radiate said mask mark,
• a second beam output system for forming the two second beams, which cross at a predetermined angle, so as to radiate said substrate mark through the transparent region of said mask, and
• an objective optical system for receiving the two first beams and the two second beams, and outputting the two first beams and the two second beams, so that radiation regions of the first and second beams are separated from each other on said mask;
• and
• a photoelectric detecting device for receiving diffracted light components of the first beams from said mask mark and receiving diffracted light components of the second beams from said substrate mark and transmitted through said projection optical system, and for outputting photoelectric signals according to intensities of the diffracted light components.

An alignment apparatus for an exposure apparatus which includes a projection optical system for focusing and projecting a pattern image on a mask onto a photosensitive substrate under exposure light, comprising:

• a beam radiation system for radiating two beams in a wavelength range different from that of the exposure light onto a diffraction grating-like mask mark formed on said mask, and a diffraction grating-like substrate mark formed on said photosensitive substrate at symmetrical angles;
• said beam radiation system including an objective optical system for receiving the two beams, and outputting the two beams so that the two beams cross on said substrate mark;
• a first photoelectric detector disposed for receiving diffracted light components generated from said substrate mark in substantially the same direction;
• a diffraction grating-like first mark arranged in or adjacent to a plane conjugate with said substrate mark such that diffracted light components generated from said mask mark are radiated onto said first mark through said objective optical system;
• a second photoelectric detector disposed for receiving diffracted light components generated from said first mark in substantially the same direction;
• a holding member for holding, integrally with said first mark, a diffraction grating-like second mark arranged to have a predetermined positional relationship with said first mark;
• an optical member for dividing a part of the two beams and guiding it to said second mark;
• a third photoelectric detector disposed for receiving diffracted light components generated from said second mark in substantially the same direction;
• and
• a detection device connected to said first, second, and third photoelectric detectors for outputting a detection signal corresponding to a relative displacement between said mask and said photosensitive substrate based on signals from said first, second, and third photoelectric detectors.

An alignment apparatus comprising:

• a beam radiation system for radiating two first beams onto a diffraction grating-like first mark formed on a first substrate and two second beams, which are discrete from the first beams on an incident side of said first substrate, onto a diffraction grating-like second mark formed on a second substrate;
• said first substrate having a region transparent to the second beams at an adjacent position in a direction perpendicular to a grating period direction of said first mark or a position neighboring said first mark;
• said beam radiation system including:
• a first beam output system for forming the two first beams, which cross at a predetermined angle, so as to radiate said first mark,
• a second beam output system for forming the two second beams, which cross at a predetermined angle, so as to radiate said second mark through the transparent region of said first substrate, and
• an objective optical system for receiving the two first beams and the two second beams, and outputting the two first beams and the two second beams, so that radiation regions of the first and second beams are separated from each other on said first substrate;
• and
• a photoelectric detecting device for receiving diffracted light components from said first mark and diffracted light components from said second mark, and outputting photoelectric signals according to intensities of the diffracted light components.

An alignment apparatus for an exposure apparatus which transfers a pattern of a mask onto a photosensitive substrate, comprising:

• a beam radiation system for radiating two first beams onto a mask mark formed on said mask, and radiating two second beams, which are discrete from the first beams on an incident side of said mask, onto a substrate mark formed on said photosensitive substrate;
• said beam radiation system including:
• a beam output system for forming said two first beams, which radiate said mask mark at separate positions, and for forming said two second beams, which pass through a transparent region of said mask and cross on said substrate mark, and
• an objective optical system for receiving said two first beams and said two second beams, and outputting the two first beams and the two second beams so that radiation regions of the first and second beams are separated from each other on said mask;
• a first photoelectric detector disposed for receiving diffracted light generated from said substrate mark;
• a member for holding integrally a first grating and a second grating, the first grating being disposed in a plane substantially conjugate with said photosensitive substrate to be irradiated by diffracted light generated from said mask mark and passing through said objective optical system, the second grating being disposed to be irradiated by light split from said two first beams and said two second beams by a beam splitter within said beam radiation system;
• a second photoelectric detector disposed for receiving diffracted light generated from said first grating;
• and
• a third photoelectric detector for receiving diffracted light generated from said second grating.

An alignment apparatus for an exposure apparatus which exposes a photosensitive substrate with a pattern of a mask comprising:

• a beam radiation system for radiating plural sets of two crossing light beams onto a grating mark formed on said photosensitive substrate, a crossing angle of the respective light beams differing from set to set, and generating diffracted light components from said grating mark in substantially the same direction by each set of light beams;
• a photoelectric detecting device for receiving said diffracted light components of each set of light beams;
• and
• a device which moves said photosensitive substrate based on an output from said photoelectric detecting device so that said photosensitive substrate and said mask are aligned.