International Business Machines Corporation

Peter H Berasi

Doris P Pulaski

Robert P Rippstein

Michael F Jerome

Lannie R Bolde

Hsing Hsiung Chen

Disclosed is a method of manufacturing a metal mask for an integrated circuit chip interconnect solder bump. The invention deposits a very thick photoresist on both sides of a very thick molybdenum foil sheet (the molybdenum sheet is at least 8 mils thick and the photoresist is at least 5 microns thick). Then the process exposes and develops the photoresist to produce at least one opening having a diameter of at least 5 mil. The invention simultaneously etches both sides of the molybdenum foil using a very low etchant spray pressure of approximately 5 psi to form at least one via in the molybdenum foil that has a diameter of at least 12 mil and a knife-edge of 0.2 mil. The photoresist is removed after the etching process.

Moly mask construction and process

A method of making, and the resultant mask, comprises developing resist layers over surfaces of a masking layer to transfer significantly reduced sized openings within glass masters attached to the surfaces of the masking layer into the resist layers. These significantly reduced sized openings within the resist layers are then transferred into the masking layer within a first etch bath by simultaneously monitoring and controlling both etchant activity and concentration of a byproduct within the etch bath formed between the masking material and the etchant. The openings may be etched to completion within the first etch bath, or alternatively, the openings may be etched to a pre-finished image size. Wherein the openings are etched to a pre-finished image size, the masking layer is immersed into a second etch bath for further micro-etching of these openings to a final desired image size.

Fine-dimension masks and related processes

A molybdenum mask for use in the sputter deposition of electrically conductive materials on preselected areas of a substrate is coated with a transition metal carbide. The carbide protects the metal images defined on the mask from degradation during mask cleaning and related processes, thereby dramatically extending the usable service life of the mask. The present invention overcomes the problem of reduced usable life of a molybdenum mask used in sputter coating and similar evaporative deposition processing.

Corrosion resistant molybdenum mask

The present invention relates generally to a new apparatus and a method for alignment verification. More particularly, the invention encompasses an apparatus that allows the imaging on a structure from opposite sides while the imaging masks are on the opposite sides of the structure, and the masks and the structure are all aligned with each other. This apparatus also discloses means that can verify that the two imaging masks that are on the opposite sides of each other are aligned with each other during imaging processing.

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Hopewell Junction, NY, United States of America

Peter H Berasi