(a) Thermogravimetric analysis of tantalum-containing resin. (b) XRD patterns, (c) diffuse reflectance spectra and (d) Kubelka-Munk plots of Ta 2 O 5 obtained at 450 and 700 C. 

(a) Thermogravimetric analysis of tantalum-containing resin. (b) XRD patterns, (c) diffuse reflectance spectra and (d) Kubelka-Munk plots of Ta 2 O 5 obtained at 450 and 700 C. 

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UV-nanoimprint lithography (UV-NIL) is a promising technique for direct fabrication of functional oxide nanostructures. Since it is mostly carried out in aerobic conditions, the free radical polymerization during imprinting is retarded due to the radical scavenging ability of oxygen. Therefore, it is highly desirable to have an oxygen-insensitive p...

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... shelf-life of the AAAc-based titanium resin was poor and thereby warrants immediate imprinting of the formulation. We speculated that this could be due to the vulnerability of tita- nium for hydrolysis, which was not averted by the chelated AAAc. Therefore, we briey studied the shelf-life and imprint- ability of a titanium resin in which AAAc was replaced with 2- (methacryloyloxy)ethyl acetoacetate (MAEAA). This formulation was found to have a good shelf life of more than a month. Furthermore, the successful direct imprinting using this MAEAA-based thiol-ene resin conrmed that the approach can be extended to other chelating monomers as well (Fig. S6 ...
Context 2
... substantiate the applicability of this thiol-ene approach for patterning other oxides, Ta 2 O 5 was chosen as the candidate due to its potential applications in semiconducting devices. 68,69 Although tantalum is a pentavalent metal, we used 4 equiva- lents of AAAc in order to match with the corresponding titanium precursor. The resultant resin was found to have a good shelf life of more than a month. The PETMP ratio to the AAAc was xed in the similar fashion to that used in TAP-0.5 and the FT-IR analyses before and aer UV light exposure were performed (Fig. S7 †). The results revealed the disappearance of the -SH stretching peak, indicating the occurrence of thiol-ene photo- click chemistry. Fig. 6 shows the TGA, XRD and diffuse reec- tance spectra of the tantalum-containing resin. The TGA prole was observed to be in similar nature to that of TAP-0.5. The complete mass loss was found to occur at $530 C and the residual inorganic mass corresponding to Ta 2 O 5 was observed to be 20.1%. The XRD pattern of Ta 2 O 5 was found to be broad, indicating its amorphous nature at this temperature. Therefore, the UV-cured lm was calcined at 700 C to obtain crystalline Ta 2 O 5 . The XRD analysis of this sample revealed well-dened orthorhombic crystalline phase of Ta 2 O 5 (JCPDS no. 79- 1375). 70 The diffuse reectance and the corresponding Kubelka- Munk plots revealed a shallow spectrum for the 450 C calcined sample, conrming the amorphous nature of the Ta 2 O 5 . The thin lm calcined at 700 C was found to exhibit a band gap of 4.26 eV, which is similar to that reported in the literature. 71 UV imprint lithography of the tantalum-containing resin was performed and the FE-SEM images corresponding to the as- imprinted and calcined samples are shown in Fig. 7. The line and space feature sizes of the as-imprinted patterns were found to be $1.7 and $2.1 mm, respectively. Aer calcination, the lines were shrunk to $470 nm and the spaces extended to $3.4 mm. The cross-sectional view of FE-SEM images of the as-imprinted and calcined samples showed the heights to be $1.7 mm and 410 nm, respectively. Thus, the lateral and vertical shrinkages were found to be $75% that is similar to the case of TiO 2 . The very similar imprinting behavior of tantalum-containing resin shows the capability of the thiol-ene approach to be a potential route for fabricating nanostructures of a host of oxides that could nd applications in various ...

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... As such, we observe that the decrease in intensity of the FTIR band at 2,572 cm −1 ( Figure 3A) after UV-curing shows characteristic bond between thiolenes and allyl ethers (Nagarjuna et al., 2018). Based on the obtained Raman spectra of cured NOA73 ( Figure 3B) and taking into account the findings reported in the literature (Mongkhontreerat et al., 2013), we can conclude that the main components in NOA73 are triallyltriazinetrione and tris [2-(3-mercaptopropionyloxy)ethyl]isocyanurate in a molar proportion of at least 1:5, using 2,2-dimethoxy-2phenyl-acetophenone as photoinitiator and triallyl isocyanurate as crosslinking catalyst (Sanoria et al., 2015). ...
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... Also, the peak at 1633 cm -1 of the carbon-carbon double bond in CAB modified with TMPTA and acrylate groups was observed to decrease the density of the peak of the carbon-carbon double bond since most of the acrylate groups were spent cross-linking with free -SH or other acrylate groups. Nagarjuna et al. have reported a similar spectrum in their films prepared using thiol-ene click reaction under UV rays (Nagarjuna et al. 2018). ...
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... A salient feature of thiol−ene polymerization compared to chain-growth polymerization is its insensitivity to oxygen inhibition. 47 This was first confirmed by unchanged polymerization kinetics and particle size when purging the reactor with nitrogen to flush out oxygen (Table S2, Supporting Information). On the other hand, lower M̅ n values leveling off at approximately 10,300 g mol −1 were systematically obtained in photopolymerization under a nitrogen atmosphere. ...
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