International Business Machines Corporation

Charles A Cortellino

Joseph E Levine

Kie Y Ahn

Wayne Martin Moreau

Stephen Bruce Brodsky

Edward Gipstein

Henry C Schick

Duane E Johnson

Saryadevara Basavaiah

William A Hewett

A mask for deposition of electrically-conductive paste material on a ceramic base, in the construction of electric circuits having multiple electronic chips is formed of molybdenum with a titanium nitride coating. The coating passes through apertures of a mesh on one side of the mask and continues through the apertures to appear in cutouts of stencils along the opposite side of the mask. Other elements of the fourth group of the periodic table, such as zirconium, may be employed in lieu of the titanium in the formation of the coating. The coating is uniformly applied by a sputtering procedure in which nitrogen is sprayed uniformly along the mask and away from a titanium target. In an argon plasma, the nitrogen and the titanium are sputtered onto the molybdenum where the titanium and nitrogen combine to form the coating.

Coated mask for photolithographic construction of electric circuits

This developer station comprises a developing tank arranged with a centrally located rotatable and vertically translatable shaft carrying a workpiece platform at the upper end thereof. Initially, the platform is located above the tank for ease in loading a workpiece, for example an exposed photoresist coated semiconductor device component. The workpiece is then lowered into developing solution in the tank where it is rotated and oscillated vertically for agitational action during a predetermined time period after which it is raised up out of the solution and delayed at a drying station for another predetermined time period. Thereafter, the workpiece is returned to the initial position for unloading.

Developing apparatus for exposed photoresist coated wafers

The development of high energy radiation exposed positive acrylate polymer resist layers by organic liquid developers, such as methyl isobutyl ketone, is improved by adding water to the ketone.

High energy radiation exposed positive resist mask process

It has been discovered that the sensitivity of positive acting polymeric electron beam resists is increased by well over an order of magnitude by using polymers having a molecular weight of at least one million, thereby making it possible to reduce the required radiation to below 3 .times. 10.sup..sup.-6 coulombs/cm.sup.2.

Positive polymeric electron beam resists of very great sensitivity

A resist mask is formed by coating on a substrate a layer of a polymer, such as polymethyl methacrylate, which is degradable by high energy radiation, such as a scanning electron beam. The layer is exposed to high energy radiation in a patternwise manner so as to lower the molecular weight of the polymer in the exposed portions. The layer is developed to remove the exposed portions by immersing the layer in a developer which consists of alkyl acetates and ketones having between 7 and 9 carbon atoms and mixtures thereof at a temperature of at least about 40.degree. C.

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Wappingers Falls, NY, United States of America

Charles A Cortellino