The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 05, 1980
Filed:
May. 10, 1978
Eckart Hundt, Haar, DE;
Siemens Aktiengesellschaft, Berlin & Munich, DE;
Abstract
In an illustrative embodiment marks with dual x-ray permeable apertures are at three spaced locations on the mask and transmit x-ray beams which are directed obliquely to the semiconductor surface. In this case, the marks on the semiconductor disc may be formed by monocrystals shaped in conformity with the incident beam cross section and located so as to produce reflected x-ray beams which intersect correspondingly shaped further apertures of the respective dual aperture marks on the mask. Alternatively the beams may impinge on the surface of the semiconductor disc itself at an angle to produce reflection, with x-ray absorbing material surrounding each reflecting region. In either case the reflected beams as transmitted by the further apertures are detected as a measure of the degree of parallelism of the mask and semiconductor disc.