As and Epitaxial-Growth MnSi Thin Films - OPUS Würzburg

Chapter 6
Epitaxial Growth of MnSi Thin
Films
This chapter details the preliminary results of the development of in-house MnSi thin film
growth in our group. In this chapter, we describe the material grown for this work and
the preliminary characterization techniques done to verify its material properties. The
following chapters would focus on the magnetoransport behavior of the grown thin films
and implications to future work.
6.1 Epitaxial growth of MnSi Thin Films
The aim of this work is to establish the growth of MnSi thin films within our group and
characterize their transport properties for future optimization and applications. Following
the work of [Magn 10], thin film MnSi samples on Si[111] were grown by MBE by
Christoph Pohl of EPIII using a co-deposition technique. In the co-deposition method,
a layer of Mn is first deposited at room temperature on the cleaned substrates and then
subsequently annealed at higher temperatures. (≈ 400 deg Celsius at high Si and Mn
atmosphere)
The films were grown on boron-doped single-side polished Si[111] substrates and the
substrates are used and cleaned using standard preparation techniques with an additional
step of growing a Si (approximately 32 nm-thick) buffer layer to smoothen the substrate
surface before deposition of the Mn layer. Figure 6.1 shows the RHEED pattern from
MnSi growth on Si, which indicates crystalline growth/formation. After film growth, a
thinSicapisgrownontopofthelayer. Dependingonthesubstrategrowth, anamorphous
(a-Si) or crystalline (c-Si) is deposited as cap to prevent oxidation.
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