Error-corrected corpuscular beam lithography

US4578587A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Uwe Behringer · Herrenberg, DE
• Harald Bohlen · Eppelheim, DE
• Peter Nehmiz · Stuttgart, DE
• Werner Zapka · Gärtringen, DE

Key dates

• Filing date: Jan 25, 1985
• Grant date: Mar 25, 1986
• Expiry date: Jan 25, 2005

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01J2237/31798
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

An apparatus and method for testing transmission masks for corpuscular lithography, in which an image of a portion of mask is guided across a pinhole diaphragm, comprising at least one aperture with submicron dimensions, by inclining the corpuscular beam. The relative spacing of two measuring points is derived from the interferometrically measured table displacement and the beam inclination. This test for geometrical errors is effected by placing below the single hold in the diaphragm a scintillator followed by a photomultiplier coupled to an output circuit. For testing the entire mask area for errors and impurity particles, a multihole diaphragm, having submicron apertures arranged in matrix fashion, can be used above an integrated circuit of the charge transfer type which provides a MOS capacitor as a particle detector underneath each diaphragm opening. The exposure mask is scanned in steps, effecting several single exposures at each position by inclining the beam.