Publications

Abstract not provided.

We report on a scalable electrostatic process to transfer epitaxial graphene to arbitrary glass substrates, including Pyrex and Zerodur. This transfer process could enable wafer-level integration of graphene with structured and electronically-active substrates such as MEMS and CMOS. We will describe the electrostatic transfer method and will compare the properties of the transferred graphene with nominally-equivalent 'as-grown' epitaxial graphene on SiC. The electronic properties of the graphene will be measured using magnetoresistive, four-probe, and graphene field effect transistor geometries [1]. To begin, high-quality epitaxial graphene (mobility 14,000 cm2/Vs and domains >100 {micro}m2) is grown on SiC in an argon-mediated environment [2,3]. The electrostatic transfer then takes place through the application of a large electric field between the donor graphene sample (anode) and the heated acceptor glass substrate (cathode). Using this electrostatic technique, both patterned few-layer graphene from SiC(000-1) and chip-scale monolayer graphene from SiC(0001) are transferred to Pyrex and Zerodur substrates. Subsequent examination of the transferred graphene by Raman spectroscopy confirms that the graphene can be transferred without inducing defects. Furthermore, the strain inherent in epitaxial graphene on SiC(0001) is found to be partially relaxed after the transfer to the glass substrates.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

Abstract not provided.

This model predicts thermal boundary conductance at interfaces where one material comprising the junction is characterized by high elastic anisotropy (i.e, graphite). The thermal properties of graphite are determined through a simplified vibrational model, where the bulk structure is treated as an linear assembly of two-dimensional systems. This model is validated at temperatures above cryogenic through comparison to experimentally determined values of specific heat. Elastic processes are accounted for through traditional diffuse transport theory. Inelastic contributions due to multi-phonon processes are also addressed and quantified.

Thermal boundary resistance dominates the thermal resistance in nanosystems since material length scales are comparable to material mean free paths. The primary scattering mechanism in nanosystems is interface scattering, and the structure and composition around these interfaces can affect scattering rates and, therefore, device thermal resistances. In this work, the thermal boundary conductance (the inverse of the thermal boundary resistance) is measured using a pump-probe thermoreflectance technique on aluminum films grown on silicon substrates that are subjected to various pre-Al-deposition surface treatments. The Si surfaces are characterized with Atomic Force Microscopy (AFM) to determine mean surface roughness. The measured thermal boundary conductance decreases as Si surface roughness increases. In addition, stripping the native oxide layer on the surface of the Si substrate immediately prior to Al film deposition causes the thermal boundary conductance to increase. The measured data are then compared to an extension of the diffuse mismatch model that accounts for interfacial mixing and structure around the interface. © 2010 by ASME.