Nanoscale Mapping of Thermal and Mechanical Properties of Bare and Metal-Covered Self-Assembled Block Copolymer Thin Films

Abstract

We report on the structural, mechanical and thermal analysis of 40 nm thick polystyrene-blockpoly (ethylene oxide) (PS-b-PEO) block copolymer (BCP) films coated with evaporated chromium layers of different thicknesses (1, 2 and 5 nm). Solvent annealing processes allow the structural control of the BCP films morphology by re-arranging the position of the PEO cylinders parallel to the substrate plane. High-vacuum scanning thermal microscopy and ultrasonic force microscopy measurements performed in ambient pressure revealed that the nanometer thick metal coated layers strongly influence the heat dissipation in the BCP films and the local surface stiffness of the individual BCP domains, respectively. The measured tip-sample effective thermal resistance decreases from 6.1×10 7 to 2.5×10 7 KW -1 with increasing Cr film thickness. In addition, scanning probe microscopy measurements allow the thermal and mechanical mapping of the two segregated polymer domains (PEO-PS) of sub-50 nm characteristic sizes, with sub-15 nm thermal spatial resolution. The results revealed the effect of the surface morphology of the BCP and the incorporation of the metal film on the nanoscale thermal properties and volume self-assembly on the mechanical properties. The findings from this study provide insight in the formation of high aspect ratio BCP-metal structures with the more established applications in lithography. In addition, knowledge on the thermal and mechanical properties at the nanoscale is required in emergent applications, such as thermal management, where the BCP is part of the final structure or device.

Poly(alkylene 2,5-furanoate)s thin films: Morphology, crystallinity and nanomechanical properties

“…Lately, there has been a continuous increase in the use of high-resolution nanomechanical measurements to study polymer materials [43][44][45][46][47][48][49] Based on the PF-QNM maps, and using the same calibration, we performed force spectroscopy measurements on selected regions of the thin films. For these measurements, we applied a linear ramp of 200 nm length in the Z direction of the piezo scanner (vertical movement).…”

Poly(alkylene 2,5-Furanoate)s Thin Films: Morphology, Crystallinity and Nanomechanical Properties

“…All thermal treatments were performed using a Linkam THMS600 stage connected to a T95-LinkPad System controller. Lately, there has been a continuous increase in the use of high-resolution nanomechanical measurements to study polymer materials [43][44][45][46][47][48][49]. In our work, the nanomechanical studies were performed combining the PeakForce-Quantitative Nanomechanical Mapping (PF-QNM)…”

Selective Deposition of Copper on Self-Assembled Block Copolymer Surfaces via Physical Vapor Deposition

“…39 showed preferential coverage by Ti and Cr, respectively, of the PS domains of a PSb-polyethylene oxide (PS-b-PEO) surface. Muller-Buschbaum, i v i d u a l n o t d i r e c t l y a s s o c i a t e d w i t h s c i t e i s p r o h i b i t e d .…”