Allied Corporation

Petrarch Systems

Microsi, Inc.

Petrarch System, Inc.

Robert A Owens

James M Lewis

Roland L Chin

Susan A Ferguson

Andrew J Blakeney

Richard F Sweeney

Robert E Rinehart

Valentine T Zuba

Ronald W Wake

A high contrast developing process is described for use after pre-exposure to UV-visible radiation to produce increased sensitivity during lithographic processing of positive resist layers. Compared to samples which have not been subjected to the methods of this invention, sensitivity increases of a factor of 2-4 are to be expected. An additional benefit of low film loss from unexposed resist is obtained. The system disclosed is applicable to lithographic exposures utilizing electrons, photon (e.g. UV-visible, x-rays, etc.) and atomic or molecular charged particles. Specifically, as a result of the increased sensitivity, higher throughput during lithographic processing for the fabrication of photomasks and semiconductor devices is realized.

Pre-exposure method for increased sensitivity in high contrast resist

A positive photoresist metal ion aqueous developer is provided that gives a high contrast to the photoresist. The developer disclosed comprises a formulation of aqueous alkali-base such as potassium hydroxide and a carboxylated surfactant. The incorporation of the carboxylated surfactant provides the unexpected increase in the contrast of the photoresist. The addition of the carboxylated surfactant increases the gamma from a typical photoresist gamma (.gamma.) of 3 or less to a gamma greater than 5. The high contrast photoresist provides linewidth control and affords improved process latitude in photoresist imaging. The linewidth control is particularly critical in cases where fine lines are to be defined in the resist that covers steps of topography on the coated substrate. The higher the contrast, the less affected the resist by the topography, provided the exposure is adequate to expose the resist. The process latitude afforded by the high contrast is a result of the ability to over develop (develop longer) the exposed resist without affecting the unexposed resist in the adjacent areas.

High contrast photoresist developer

High contrast, sensitivity and bath life is obtainable by the addition of inorganic salts, preferably a carbonate, to an aqueous alkali metal base containing a carboxylated surfactant. The preferred alkali metal bases are potassium hydroxide or sodium hydroxide. The carboxylated surfactants contemplated by the invention are those encompassed with the formula:

Process of using high contrast photoresist developer with enhanced

Process of developing radiation imaged photoresist with alkaline

A positive photoresist metal ion aqueous developer is provided that gives a high contrast to the photoresist. The developer disclosed comprises a formulation of aqueous alkali-base such as potassium hydroxide and a fluorocarbon surfactant. The incorporation of the fluorocarbon surfactant provides the unexpected increase in the contrast of the photoresist. The addition of the fluorocarbon surfactant increases the gamma from a typical photoresist gamma (.gamma.) of 3 or less to a gamma greater than 10. The high contrast photoresist provides linewidth control and affords improved process latitude in photoresist imaging. The linewidth control is particularly critical in cases where fine lines are to be defined in the resist that covers steps or topography on the coated substrate. The higher the contrast, the less affected the resist by the topography, provided the exposure is adequate to expose the resist. The process latitude afforded by the high contrast is a result of the ability to over develop (develop longer) the exposed resist without affecting the unexposed resist in the adjacent areas.

Process of forming high contrast resist pattern in positive photoagent

A novel photoresist formulation is provided which provides low striations and excellent wetting properties. The photoresist composition may be applied by spin casting on various substrates used in integrated circuit manufacture. The essential component in this invention is the solvent composition which consists of cyclopentanone (or cyclopentanone-cyclohexanone blend) in combination with an aliphatic alcohol of 5-12 carbon atoms. These solvent components when used in certain specific ratios provide unexpectedly good wetting of various substrates and low striation films.

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East Amherst, NY, United States of America

Robert A Owens