MRSEC Program Overview

Welcome to the internet hub of the Materials Research Science and Engineering Centers (MRSEC). This website provides organized information and resources at the various MRSECs for the international scientific, industrial, and educational materials research and development communities.

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Program Highlights

March 25, 2015

Self-Assembly of Oligomeric Block Copolymer Coatings for Use in Lithographic and Nanopatterning Applications

Strongly segregated block copolymer systems with low degrees of polymerization (N) are needed to prepare ultrahigh density features for emerging applications in microelectronics and magnetic storage. Here, a set of poly(cyclohexylethylene)-b-poly(lactide) (PCHE-b-PLA) copolymers were prepared to achieve sub-10 nm or even sub-5 nm domain sizes. Ordered thin films of PCHE-b-PLA with ultra-small vertical cylinders were then fabricated through spin-coating and solvent annealing. An AFM image showing sub-5 nm patterns from a PCHE-b-PLA material with a molar mass of 4.5 kg/mol post PLA etching is given in Figure with the d-spacing and morphology confirmed by GISAXS. This work has given some of the smallest patterns ever achieved in block polymer thin films.
March 25, 2015

Hall Effect and Near-Metallic Transport in Rubrene

Electrical transport in single crystals of the benchmark organic semiconductor rubrene was explored using the electric double layer transistor (EDLT) testbed. The EDLT allows very high surface charge accumulation on rubrene by virtue of the enormous double layer capacitance. The large charge densities, up to 0.3 holes per rubrene molecule, were unambiguously confirmed for the first time by Hall measurements. Further, at the highest charge density, 2D metallic transport was nearly achieved as demonstrated by resistance measurements as a function of gate voltage and temperature down to 8 K. The field-induced metal-insulator transition, a long sought goal, appears within reach for organic materials using the EDLT testbed.