Calorimetry of epitaxial thin films

Journal Article · Tue Feb 15 00:00:00 EST 2011 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.3554440· OSTI ID:22062257

Cooke, David W; Hellman, F ^[1]; Groves, J R; Clemens, B M ^[2]; Moyerman, S; Fullerton, E E ^[3]

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1. Department of Physics, University of California at Berkeley, Berkeley, California 94720-7300 (United States)
2. Department of Materials Science, Stanford University, Stanford, California 94305 (United States)
3. Center for Magnetic Recording Research, University of California at San Diego, La Jolla, California 92093-0401 (United States)

Thin film growth allows for the manipulation of material on the nanoscale, making possible the creation of metastable phases not seen in the bulk. Heat capacity provides a direct way of measuring thermodynamic properties of these new materials, but traditional bulk calorimetric techniques are inappropriate for such a small amount of material. Microcalorimetry and nanocalorimetry techniques exist for the measurements of thin films but rely on an amorphous membrane platform, limiting the types of films which can be measured. In the current work, ion-beam-assisted deposition is used to provide a biaxially oriented MgO template on a suspended membrane microcalorimeter in order to measure the specific heat of epitaxial thin films. Synchrotron x-ray diffraction showed the biaxial order of the MgO template. X-ray diffraction was also used to prove the high quality of epitaxy of a film grown onto this MgO template. The contribution of the MgO layer to the total heat capacity was measured to be just 6.5% of the total addenda contribution. The heat capacity of a Fe{sub .49}Rh{sub .51} film grown epitaxially onto the device was measured, comparing favorably to literature data on bulk crystals. This shows the viability of the MgO/SiN{sub x}-membrane-based microcalorimeter as a way of measuring the thermodynamic properties of epitaxial thin films.

• OSTI ID: 22062257
• Journal Information: Review of Scientific Instruments, Vol. 82, Issue 2; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CALORIMETERS
CALORIMETRY
CRYSTAL GROWTH
CRYSTALS
DEPOSITION
EPITAXY
ION BEAMS
IRON ALLOYS
MAGNESIUM OXIDES
MEMBRANES
NANOSTRUCTURES
RHODIUM ALLOYS
SPECIFIC HEAT
SYNCHROTRON RADIATION
THIN FILMS
X-RAY DIFFRACTION