Block copolymers with lines and spaces in the 100 Å regime have been oriented using a perfectly neutral top coat and bottom coat and these structures have been successfully developed with RIE to provide high aspect ratio topographic features. Under these conditions, the materials can be annealed in less than 60 seconds. Future work will be directed toward continued increases in χ and development of simple and efficient processes for orienting these structures.

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To extend the scaling beyond the most widely used poly(styrene-b-methyl methacrylate) (PS-b-PMMA), organic high-χ block copolymers (BCPs) were developed. Vertically oriented BCP domains were obtained by simple coat and bake process without application of an additional layer of a topcoat material. In addition, process-friendly conditions including low bake temperature (< 200 °C) and short bake time (≤ 5 min) provided a simple scheme to integrate these high-χ block copolymers to standard lithography process and pre-patterns defined by 193i lithography. Successful demonstration of directed self-assembly of these high-χ block copolymers on 193i-defined guiding pre-patterns offers a simple route to access well-aligned perpendicular lamellae and cylinders with a pitch less than 20 nm.

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Directed self-assembly (DSA) technique has been focused as the novel semi-conductor manufacturing process replacing photo-lithography process for semi-conductor applications. We synthesize block copolymers (BCP) containing silicon unit, which show cylinder and lamellae structure from micro-phase separation by only heat annealing (220 °C/ 60 sec). Moreover, we could get hexagonal cylinder, maybe lamella structure along the guide pattern for pattern division by grapho-epitaxy. The examined BCPs are expected to be promising materials for sub 10 nmhP patterning.

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Two series of DDSQ (double-decker silsesquioxane)-containing oligomers were synthesized and their self-aggregation behaviors were investigated. Result shows that DDSQ-(C18-2A) could form well-organized lamellar structure with a d-spacing 8.2 nm. Considering the demand of microelectronic industry, this branched alkylated DDSQ may serve as an excellent candidate for the next generation fabricating materials.

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A photochemical process for transfer printing patterns formed by block copolymer thin films is described here. An unpatterned, transparent substrate coated in liquid conformal layer is pressed to an epitaxially aligned block copolymer thin film. Irradiation through the sample stack by UV light drives a benzophenone-mediated grafting reaction which covalently bonds the top surface of the block copolymer film to the photopolymerized conformal layer. Separation of the sample stack recovers the original guiding pattern as well a new chemically patterned substrate replicated from the original pattern. Using a single lithographically directed chemical pattern, 10 replicas are generated, each possessing 28 nm periodicity, perpendicularly oriented microdomains, and long-range epitaxial alignment.

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Gel particle is a primal defect in block copolymer (BCP) layer in directed self assembly lithography(DSAL). We studied gel removal performance for various lithography process filters and found that nylon 6,6 membrane outperformed other membrane materials exerting adsorption performance similarly to the conventional chemical amplified resist (CAR) filtration. Contrary to the CAR, BCP is synthesized using metal polymerization initiator and the metal in the resist layer should be removed to prevent potential impact to the device integrity failure or the yield loss. We also studied metal reduction from the BCP solution using ion exchange filter and particle removal filters. As a result, ion exchange filter effectively reduced metals from BCP solution as expected. In addition, unexpectedly, nylon 6,6 membrane best reduced some metal species in the BCP solution.

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The controlled synthesis of poly(styrene-block-trimethylstannylstyrene) has been accomplished. Thin films of the polymer were successfully oriented perpendicular to the substrate through use of neutral top and bottom coats to produce well-formed lamellae with the classical finger print pattern. Preliminary blanket etch studies show that the inclusion of tin into the block copolymer provides very high etch contrast for selective removal of the styrene block in both oxygen and fluorine plasma conditions. The etch rate of the tin polymer is significantly slower than that of thermal oxide under the conditions studied. Future work will be directed toward the synthesis of a sample with smaller pitch and to a study of the potential for use of organotin polymers for the patterning of fused silica imprint templates.

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The reduction of local recurrence of metastatic spinal tuomors after intratumoral excision improves the quality of life. We have developed a novel photodynamic therapy (PDT) comprising an indocyanine green (ICG)-labeld nanocarrier (ICG-lactosome) and near-infrared light for use as an intraoperative adjuvant therapy. ICG-lactosomes accumulated in bone metastases from breast cancer because of enhanced permeability and retention effect. The cytotoxic effects of this novel PDT on human breast cancer cells were confirmed. In conclusion, ICG-lactosomes enable selective tumor imaging and represent a potential new PDT photosensitizer for adjuvant therapy during surgery for bone metastases from human breast cancer.

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Techniques for the visualization of target proteins by small-molecule probes in living systems are highly important to investigate the function, dynamics, localization, and crosstalk of individual proteins. We have studied inhibitors of hypoxia-inducible factors (HIF), which are heterodimeric (α/β) transcriptional factors and major physiological stimuli for expression of angiogenesis factors. Inhibition of tumor-induced angiogenesis prevents growth of many types of solid tumors, thus is considered to provide a novel approach for cancer treatment. We recently developed carborane-containing phenoxyacetanilides as potent inhibitors of HIF-1α activation under hypoxia. We designed their photoaffinity labeling molecules to clarify the action mechanism against the HIF inhibition. Using the photoaffinity labeling molecules, we identified that heat shock protein (HSP) 60 is the target protein and clarified that HSP60 has an important role for stabilization of HIF-1α under hypoxia.

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Ribosome display has been widely used for in vitro protein evolution, and the formation of a ternary complex, mRNA-ribosome-protein, is central to this technology as it displays the genotype-phenotype linkage. In conventional ribosome display methods, DNA with a native sequence containing stop codons cannot be used as a starting material as the ribosome in the ternary complex is primarily stalled by the removal of stop codons. Here, a new method for ribosome display is reported. This new method enables the use of DNA containing a stop codon as a starting material and presents the ribosome display on a microarray format with the assistance of a photo-crosslinker. This method is expected to be more advantageous than the conventional method as it allows the use of DNA with a native sequence without any modification, and since it is presented on a microarray format, it enables immediate functional identification and comparison between different proteins without any downstream processing.

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We have developed photo-induced pH-responsive systems using NBA that release protons via a photoinitiated reaction. The photo-induced pH jump reaction was integrated into various materials such as pH-responsive hydrogels, microfluidic devices, and nanoparticles. The spatio-temporal control of their properties upon photo irradiation has been successfully demonstrated. This technique can potentially be utilized to create smart platforms such as remote and programmed delivery of drugs or effective target molecule separation in the microfluidic channels.

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We propose an advanced micromolding process for integrating heteromaterial micro- elements with complicated structures into a plastic substrate. The technique comprises the autonomous filling of dispensed liquid prepolymers into microstructures pre-engraved on a plastic substrate and subsequent curing to induce the cross-linking of the prepolymers. Specifically, the fabrication of a self-standing poly(dimethylsiloxane) elastomer membrane into a rigid plastic substrate has been investigated. Based on the experimental results, a guiding principle for the dimension control of the finally formed structure is discussed by considering the balance between the capillary force and gravity acting on the liquid prepolymer. Moreover, the present technique has been preliminarily applied to a lab-on-a-chip technology: the implementation of elastomer-based pneumatic microvalves on plastic-based microfluidic devices.

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From a ternary gaseous mixture of cobalt tricarbonyl nitrosyl (Co(CO)₃NO), tetraethylgermane (TEG), and propenyltrimethylsilane (allyltrimethylsilane) (ATMeSi), magnetic ultrafine particles were produced under irradiation with intense Nd:YAG laser light. From FT-IR spectra, chemical structure of the ultrafine particles was investigated. The spectrum of the magnetic particles was essentially the same to the one of the ultrafine particles produced from a binary gaseous mixture of Co(CO)₃NO and ATMeSi, suggest- ing strongly that TEG molecules did not contribute significantly to particle formation process. On the other hand, in the gaseous phase, depletion rate of TEG molecules was accelerated by 800 times due to the presence of Co(CO)₃NO molecules, showing that TEG molecules interacted efficiently with Co(CO)₃NO molecules to produce some volatile chemical species in the gas phase under laser light irradiation. Magnetization of the ultrafine particles was measured using a SQUID magnetometer. Magnetic susceptibility of the ultrafine particles was evaluated to be ∼1×10^-2 emu/g, suggesting that the deposited ultrafine particles were mainly composed of ferromagnetic species. The morphology of the coagulated particles was studied by taking HRTEM images. The ultrafine particles were composed of several kinds of particles which involved both the polycrystalline phase and amorphous phase. Crystalline phase was mainly composed of Co atoms, and may be responsible for ferromagnetic properties of the particles.

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We proposed rapid photopolymerization of oligodeoxynucleotides (ODNs) by 3-cyanovinylcarbazole (^CNVK), which photoirradiates the crosslinking between DNA strands at 366 nm. This photopolymerization of ODNs using ^CNVK was completed by the photoirradiation for within two seconds, the reaction rate of which is faster than any other method such as enzymatic and chemical ligation. Moreover, the photopolymerized DNA structure was degraded to the monomer ODN by photoirradiation at 312 nm. The photopolymerized DNA structure has B-form the same as the native helical duplex structure and its structure attained thermal resistance when maintained at a temperature of 60°C. Sequence specific photopolymerization incorporating micro RNA was also successful.

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One of most promising technique for the extension of 193nm immersion lithography must be Self-Aligned Multiple Patterning (SAMP) at the present. We have studied this SAMP in several aspects, which are scaling capability, mitigation of process complexity, pattern fidelity, affordability and so on. On the other hand, Gridded Design Rule (GDR) concept with Single directional layout (1D layout) extended the down-scaling with 193-immersion furthermore and relieve the process variation and process complexity, represented in Optical proximity effect (OPE), by simplification of layout design. In 1D layout fabrication, key process steps might be edge placement control on grating line and controllability of hole-shrink technique for line-cutting. This paper introduces current demonstration results on pattern transfer fidelity control and hole-shrink technique as combined with unique pattern shape repair approach.

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The polymerization of exo-[(norbornenemethoxy)methyl]-1,1,1,3,3,3-hexafluoro-2-propanol (2) using a palladium catalyst gave a significantly higher Mw polymer than the endo isomer or the 80/20 mixture of endo/exo-2. To achieve similar M_w higher concentrations of formic acid chain transfer agent was needed for the exo isomer than for the 80/20 mixture. As a result, the optical density at 193 nm of the exo isomer polymer is substantially lower since less olefinic polymer end groups were formed. A subtle interplay between chain transfer mechanisms and propagation rates explains the results obtained. Isomer content in poly(2) does not affect the dissolution rate in TMAH.

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Hard masks used in lithography processes play a vital role in pattern transfer to the desired substrate. Hard mask materials can be categorized into organic and inorganic types. Examples of organic type hard masks include amorphous carbon, organo siloxane based materials with reflection control properties. These organic hard masks are deposited either by CVD process or spin-on processes. SiN, SiON and TiN are some examples of inorganic type hard masks and typically these hard masks are deposited through CVD process. In either type, key requirement is etch resistance to either oxygen rich plasma or halogen rich plasma depending on the substrate to be etched away. However, in the advanced lithography processes, in addition to good etch resistance, they also need to possess good wet removability, fill capability in high aspect ratio contacts and trenches. In this paper, we discuss the advances made in the spin-on organic and inorganic hard masks. The spin-on option provides high throughput and several alternate material options compared to CVD option. Spin-on carbon (SOC) is a high carbon containing polymer solution and as a coating material, the polymers need to be soluble in organic solvent and insoluble after curing for coating upper layer materials. Recent progress made in good filling, low outgas, high thermal stability and planarization properties required for double and quadruple patterning is presented. Similarly, novel spin-on type inorganic formulations providing Ti, W, and Zr oxide hard masks with high etch selectivity, wet removal capability and good shelf-life stability are described. These novel AZ^(R) Spin-on MHM formulations can be used in several new applications and can potentially replace any metal, metal oxide, metal nitride or silicon-containing hard mask films currently deposited using CVD process in the semiconductor manufacturing process.

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To investigate the possibility to catch up the NGL mask pattern size scaling strategy which indicated in ITRS2012, the performance of conventional mask fabricating process was examined. Current EB resist used for mask fabrication doesn’t have enough performance to resolve below hp20nm pattern. With newly developed CAR resist, the resolution limit reached to hp18nm pattern. Furthermore by using higher performance EB writer, the possibility to resolve up to hp16nm pattern was showed. The impact of proximity effect to the resist performance was examined. The resist damage induced by proximity effect degrades the resolution limit about 2nm. This is a serious problem for NGL mask manufacturing. Reducing the impact of proximity effect is one of the major challenges for developing higher resolution EB resist..

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This paper discusses the efficiency of photocyclic initiating system (PCIS) based on a pyrromethene dye (EMP), an amine as electron donor (NPG) and an iodonium salt as electron acceptor (I250) under homogenous irradiation and holographic recording. It is shown that the PCIS is more efficient than the corresponding two component systems. This high efficiency is due to a photocyclic reaction that takes places during the irradiation, inducing the recovery of the dye in the ground state and the formation of two initiating radicals. The beneficial effect on the rate of grating formation and on the diffraction efficiency is clearly noticed. At high irradiation time, the fast polymerization observed with EMP-NPG-I250 even induces the polymerization in the dark fringes leading to a decrease of the holographic diffraction efficiency. This confirms the high performance of the photoinitiating system which can be used in holographic recording provided that the irradiation dose could be controlled.

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We have devised the photocrosslinked films of diphenylfluorene and polysilanes blends on irradiation at 405 nm. Photo-decomposition of Si-Si bonds of polysilanes was successfully suppressed during irradiation of the visible light. The photocrosslinking properties were strongly affected by PEB conditions and irradiation dose. The sensitivity of PMPS/BCAFG blended film was superior to that of hb-PPS/BCAFG blended one. The photocrosslinking was mainly due to the acid-catalyzed polymerization of the epoxy moieties of BCAFG. PMPS and hb-PPS moieties were incorporated with the film by the termination reaction of the polymerization with the terminal OH groups.

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Base-amplifying and following closslinking reactions of epoxy resins were accelerated in films by using the novel monodispersed base amplifiers, which contributes to the practical application of the negative-tone photoresists with excellent photosensitivity.

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The formation of void between a PET support film and an adhesive layer is one of the reasons for the PET interfacial failure of B1 (PtBA_w-b-(tBA_x-co-2EHA_y-co-HEA_z)) after the dismantling. However, a major part of B1 specimens was occupied by pillar-like structures, even where PET interfacial failure was observed. It seems that the macroscopic morphology of adhesive layers is not only factors to determine failure modes. Although both R1 (P(tBA_x-co-2EHA_y-co-HEA_z) and the soft segment of B1 have much lower T_g than room temperature, their mechanical properties seems to be different after the dismantling treatment as being indicated by ΔC_p values. The fact that B2 is resulted in cohesive failure in spite of very low peel strength after the dismantling suggests the important role of cross-linking on cohesive force.

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In order to create a new mechanofluorochromic material, title compound (BMAAP) was designed and synthesized. BMAAP was found to readily form an amorphous glass with a glass transition temperature of 9 °C and exhibit solvatofluorochromism in solution. BMAAP was also found to exhibit fluorescence both in crystalline state and in amorphous one and the fluorescence color in amorphous state was different from that in crystalline state. Finally, we have found that BMAAP exhibited mechanofluorochromism and the phenomenon was suggested to be caused by morphological change from crystalline state to amorphous one by mechanical grinding.

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The relationship of binder polymer compositions and lithographic properties was examined and following conclusions were obtained; (1) The alternating sequence of binder polymer is preferable to the nanocomposite of excellent transparency. (2) The moiety of methacrylic acid is necessary to be 50% or more for the residue-free patterning. (3) Photo-definable nanocomposite composed of alternating copolymer and nano titania gives a patternable nanocomposite with high refractive index.

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DEPT135 was used to study the hydroxymethylation of p-cresol in basic condition. The roles of type and amount of catalyst, reaction temperature, reaction time were investigated to optimize reaction conditions for the synthesis of 2,6-dihydroxymethyl-4-methyl phenol(2,6-DHMMP). Subsequently, a series of novolac resins with extremely high or low M_W, narrow M_W/M_N, as well as alternating co-condensation structure have been produced by the condensation of 2,6-DHMMP and phenol, m-cresol etc. The synthesized p-cresol/phenol resin has a M_W of 20000-30000, and M_W/M_N of 15-20, and also excellent resistance to alcohol and alkali, which meet the needs of photosensitive compositions. The synthesized p-/m-cresol resin has a M_W of 25000, and M_W/M_N of below 15, as well as well resistance to alkali, heat and etching. These novolac resins have good prospects in terms of resist and printing plates.

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