Advanced chemically amplified resist

The concept of acid labile crosslinked units in polymers for positive DUV resist was evaluated with poly-(4-hydroxystyrene/4-vinylcyclohexanol) and implemented on a poly-4-hydroxystyrene backbone. The principle to increase the molecular weight by a transacetalization reaction was used to improve acetal protected phenolic resins for advanced chemically amplified resists. The polymer chains were linked via diols with acetal bridges. This type of linkage can be applied to a wide range of phenolic polymer binders. Resolution and thermal stability of the photoresist patterns were improved. Gel permeation chromatography and dissolution rate measurements prove that the crosslinked units remain essentially intact in the unexposed areas, thus enhancing... 

Advanced Chemically Amplified Resist Process Using Non-Ammonia Generating Adhesion Promoter... 

The second type of chemically amplified depolymerization resist mechanism depends upon the incorportation of C-O bonds into the polymer backbone which can be cleaved by either hydrolysis or addolysis. This concept was first advanced by Crivello, who proposed that polymers such as polycarbonates and polyesters could undergo photo-induced add catalyzed hydrolysis reaction in polymeric film (9, 76). Although polymers could be designed to undergo catalytic chain cleavage in the presence of add, such an approach depends upon the inclusion of stoichiometic amounts of water in the polymer film. Uttle further work was reported on this concept until recently, when a new system for dissolution inhibition was described based upon the hydrolysis of polysilyl ethers in a novolac resin (24). 

A new family of chemically amplified positive resists based on methaaylate terpolymers has been developed. The three different monomers each perform a separate function in the terpolymer. These resists were original designed for use in printed circuit board (PCB) fabrication. The flexibility of this approach in the design of positive resists has recently been demonstrated in the development of several new integrated circuit (IC) positive resists for deep UV (248 nm) and deep, deep UV (193 nm) lithography. These advances demonstrate that resists for wide application can be designed from a common platform of materials technology. 

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