Divergent Processes for the C9 to C15 Monomers of Polyamide from Vegetable Oils and Synthesis of the Dissolution Inhibitors and the Negative Tone Photoresists for ArF Photolithography

Abstract

This thesis is comprised of two chapters. Chapter 1 is Divergent processes for the C9 to C15 monomers of polyamide from vegetable oils. Chapter 2 is the Synthesis of the dissolution inhibitors and the negative tone photoresists for ArF photolithography which is divided again into 2 subjects, synthesis of the dissolution inhibitors and synthesis of the new conceptual negative tone photoresist. Chapter 1: In recent years, polymers from renewable resources have been attracting ever-increasing attention because of environmental concerns and depletion of petroleum resources. Since most of widely used polymers are generally based on fossil feedstocks, academic and industrial researchers have been increasingly concentrating their attention and efforts to the possible use of renewable feedstocks in order to keep global sustainability. Vegetable oils are one of the important renewable platform chemicals for producing polymeric materials. The main components of vegetable oils are esters of glycerol with three fatty acids, that is, triglycerides. Several reactive sites including double bonds and ester groups are present in tryglycerides. From this point of view, we developed a versatile and efficient process for the monomers of polyamide from vegetable oils as the renewable resources. We could obtain the C9-C15 α,ω-dicarboxylic acids and ω-amino acids monomers from olive oil, castor oil and rapeseed oil, respectively. All of the monomers were obtained via the carbon homologation methods followed by the functional group transformations in good to excellent yields. Chapter 2: The minimum size achievable by photolithography is already smaller than the wavelength of radiation, and the cost of improving its resolution is increasing exponentially. But, unfortunately, current technology fails to meet the demand for the miniaturization of semiconductor. In order to break the barrier, several alternative technologies called next generation lithography (NGL) are currently being developed. First, we suggested the addition of dissolution inhibitor to enhance the contrast of ArF photoresists. Dissolution inhibitors (DIs) are a class of small molecules with acid-labile unit (ALUs). DIs decompose to disclose a base-soluble functional group and change the property of the DI molecules to be washed out rapidly by a developer. We have synthesized two dissolution inhibitors from calix[4]arene which was not applied to the ArF photoresists. Methoxymethyl (MOM) and tert-butyloxycarbonyl (t-Boc) protected calix[4]arene were obtained in 73% and 58% yields, respectively, in a single step. Second, negative tone photoresist (NTR) is suggested with a new concept. Conventional negative tone development (NTD) was embodied by using organic solvent as a developer or crosslinking reactions of negative tone resist. But organic developer is not freely available from overseas patents, and a limited number of negative tone resist for ArF are available in the market. From this point of view, we designed a negative tone resist which have not a hydrophilic functionality but also hydrophobic lactone when it exposed to ArF light, together. Several candidate monomers for photoresist were synthesized, but their physical properties were not enough to apply in practical process, yet. Although the desired result was not completely obtained, new approach to synthesize negative tone resist is worthy enough.