Semiconductor(BaSi2)/metal(CoSi2) Schottky-barrier structures epitaxially grown on Si(111) substrates by molecular beam epitaxy

Abstract

We successfully demonstrated epitaxial growth of semiconductor (BaSi 2 )/metal(CoSi 2 ) Schottky-barrier structures on Si(1 1 1), for the first time, by molecular beam epitaxy (MBE). The interface between the CoSi 2 and BaSi 2 layers was found to be sharp from transmission electron microscopy (TEM) observations. The current-voltage characteristics measured at room temperature showed clear rectifying properties. When positive bias was applied to the CoSi 2 layer with respect to the BaSi 2 layer, the current increased exponentially. Electron diffraction patterns obtained using reflection high-energy electron diffraction (RHEED) and TEM are discussed. r

Photoresponse Properties of Semiconducting BaSi2Epitaxial Films Grown on Si(111) Substrates by Molecular Beam Epitaxy

“…2, which consists of alternating intense and weak streaks, reveals that the a-axis-oriented BaSi 2 has three epitaxial variants rotated by 120 to each other in the surface normal direction, due to the three fold symmetry of Si(111). 13) These results show that a-axis-oriented multidomain BaSi 2 epilayers were grown on Si(111). Figures 3(a) and 3(b) show the photoresponse spectra of BaSi 2 /Si and FZ-Si bulk, respectively, measured under various bias voltages.…”

“…9,10) To date, we have realized the epitaxial growth of BaSi 2 and Ba 1Àx Sr x Si 2 on Si(111) by reactive deposition epitaxy (RDE; Ba deposition on a hot Si substrate) and molecular-beam epitaxy (MBE; co-deposition of Ba and Si on a hot Si substrate). [10][11][12][13] Very recently, we also succeeded in controlling electron and hole concentrations in BaSi 2 by impurity doping. 14,15) However, there have been no reports on the photoresponse properties of BaSi 2 , which are very important when we discuss a quantum efficiency in BaSi 2 .…”

Exploring the potential of semiconducting BaSi2for thin-film solar cell applications

“…In spite of three epitaxial variants on Si(111), the RHEED pattern is streaky, as shown in Fig. 4(a) [30]. In contrast, as shown in Fig.…”

Large photoresponsivity in semiconducting BaSi2 epitaxial films grown on Si(001) substrates by molecular beam epitaxy

“…show the RHEED patterns of BaSi 2 films after (a) RDE at 550 °C and (a') MBE at 600 °C on Si(111), and after (b) RDE at 530 °C and (b') MBE at and Si[110], respectively. We can see clear streaky RHEED patterns for BaSi films on Si(111), which is typical for a-axis-oriented BaSi 2 epitaxial films[13]. On the other hand, two clear sets of streaky patterns with different spacings are seen forBaSi 2 on Si(001), in Figs.…”