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:
Jan. 11, 2005
Filed:
Jun. 27, 2002
Christian Crell, Forstinning, DE;
Christian Crell, Forstinning, DE;
Infineon Technologies AG, Munich, DE;
Abstract
To avoid charging effects of isolated chromium structures during the structuring of a second level of attenuated phase shift masks, a previous chromium etching step is preferably carried out in a time-controlled manner, so that a residual chromium layer, which is approximately 5-20 nm thick, remains at the bottom of the columns. The residual chromium layer connects the chromium webs, which are otherwise isolated, in a conductive manner and therefore dissipates the charge to the outside during the subsequent structuring by an electron beam. In the process steps that follow the exposure of the second level—preferably of alternating attenuated phase shift masks—two further chromium etching steps can be carried out, with a small etching depth in each case in the columns provided for the quartz etching of different phase shift.