Hydrogen silsesquioxane ͑HSQ͒ soft stamps with hard upper-part protruding areas are proposed for nanocontact printing in this study. The stamps are fabricated by low-dose E-beam lithography on low-temperature prebaked HSQ films with development in low-concentration tetramethyl ammonium hydroxide ͑TMAH͒ solution. In order to obtain an optimum nanoscale stamp, E-beam dose, TMAH concentration, and development time were set as fabrication parameters. Scanning electron microscopy ͑SEM͒ images of the HSQ stamps exhibited nanopatterns that have a superior sidewall profile: 40-190 nm lines with an aspect ratio of 6.86. New material systems are suggested in our nanocontact printing. Poly-l-lysine and aminosilane were separately used as inks for the HSQ stamps on a HSQ/Si substrate at room temperature. Ink thickness, pressing pressure, and pressing time were manipulated to find the optimum condition for the printing, and afterwards the transferred patterns were examined by the utilization of fluorescence microscope, atomic force microscopy, and SEM. Experimental results demonstrated that line patterns with about 1000 m in length of both inks are properly transferred onto the HSQ/Si substrate, and the HSQ stamps were also verified to possess good durability and repeatability.When a device size of integrated circuits is scaled down to sub-100 nm regime, the International Technology Roadmap for Semiconductors ͑ITRS͒ estimates that the semiconductor industry is being pushed to deliver the 32 nm node in 2013. 1 Several nanofabrication methods are currently considered for the next-generation lithography ͑NGL͒ tools. Among them, nanoimprint lithography ͑NIL͒ is a promising technique because of its low-cost, highthroughput nanoscale patterning. NIL can imprint functional device structures in polymers, which defines its versatility in areas of photonics and biotechnology as well. 2 The family of nanoimprint technologies contains a large variation of stamp-based lithographic processes. 2 One process is microcontact printing lithography, which utilizes soft stamps and appropriate small-molecule inks to print self-assembled monolayer ͑SAM͒ patterns on substrates at low temperature and pressure. 3 It provides a precise replication of microscale features, and makes postprocessing more manageable. Polydimethylsiloxane ͑PDMS͒ is the preferred stamp material for microcontact printing. However, the low elastic modulus of PDMS and the diffusion of small-molecule inks restrict the replication of features in the nanoscale. Much effort has been concentrated toward the development of PDMS and potential inks. 4-8 Schmid and Michel found an increase in the Young's modulus of PDMS by incorportating "hard" h-PDMS to improve the mechanical stability of the features during the stamp printing process. 4 Li et al. synthesized a two-layer V-shaped stamp, a layer of Sylgard 184 PDMS supporting another film of stiff V-shaped h-PDMS, and printed a 42 nm linewidth and 3 m pitch G4 PANAM transferred pattern, but the stamp required a 12 h curing at 80°C. 8 Nak...

No abstract

No abstract

In this study, inverted organic solar cells (IOSCs) have been fabricated and characterized. Device's structure consists of the blend of poly(3-hexythiophene)(P3HT) and [6,6]-phenyl C61-butyric acid methyl ester(PCBM) as an active layer and a solution process of ZnO and V 2 O 5 as a hole blocking layer (HBL) and electron blocking layer (EBL), respectively. The blocking layer possesses high charge mobility and wide band gap. The wide band gap can effectively suppress the diffusion of electron and hole separating from exciton to the electrodes, reducing the combined effect. Experimental results reveal that ZnO annealed in high temperature to procure nano-ridge can effectively enhance electrons to transport from active layer to the cathode.

Nanocontact printing using hydrogen silsesquioxane (HSQ) soft stamps is studied for nanobio device fabrications in this work. The stamps with designed linewidth 80-200 nm were fabricated by low-dose e-beam lithography on HSQ films. The contact printing technique by using aminosilane as the ink on O2 plasma treated HSQ/Si substrates was developed. The plasma treatment, stamping force and stamping time were manipulated, and afterwards the transferred patterns were examined by the utilization of atomic force microscope and scanning electron microscope. Experimental results demonstrate that the nano-features on the HSQ stamps can be successfully transferred onto the substrates and passed a 3M tape peeling test under specific conditions in the range of 100-200 W O2 plasma treatment for 30 s. Nanolines with printed linewidth 97-205 nm were obtained. The nanopatterning of an antibody affinipure goat anti-mouse IgG(H+L) was also demonstrated onto the transferred aminosilane pattern surfaces for bio-device fabrication.