scholarly journals Interfacial stability of ultrathin films of magnetite Fe3O4 (111) on Al2O3(001) grown by ozone-assisted molecular-beam epitaxy

2017 ◽  
Vol 110 (2) ◽  
pp. 021601 ◽  
Author(s):  
Hawoong Hong ◽  
Jongjin Kim ◽  
Xinyue Fang ◽  
Seungbum Hong ◽  
T.-C. Chiang
1991 ◽  
Vol 237 ◽  
Author(s):  
T. George ◽  
R. W. Fathauer

ABSTRACTThe stability of CoSi2/Si interfaces was examined in this study using columnar suicide structures grown on (111) Si substrates. In the first set of experiments, Co and Si were co-deposited (1:7 flux ratio) using molecular beam epitaxy at 800°C and the resulting columnar suicide layer was capped by epitaxial Si. Deposition of Co on the surface of the Si capping layer at 800°C results in the growth of the buried suicide columns. The buried columns grow by subsurface diffusion of the deposited Co, suppressing the formation of surface islands of CoSi2. The columns' sidewalls appear to be less stable than the top and bottom interfaces, resulting in preferential lateral growth and ultimately in the coalescence of the columns to form a continuous buried CoSi2 layer.In the second set of experiments, annealing of a 250nm-thick buried columnar layer at 1000°C under a 100nm-thick Si capping layer results in the formation of a surface layer of CoSi2 with a reduction in the sizes of the CoSi2 columns. For a sample having a thicker (500nm) Si capping layer the annealing leads to Ostwald ripening producing buried equiaxed columns. The' high CoSi2/Si interfacial strain could provide the driving force for the observed behavior of the buried columns under high-temperature annealing.


2018 ◽  
Vol 386 ◽  
pp. 110-115
Author(s):  
Maxim Viktorovich Ivanchenko ◽  
Elena Anatolyevna Borisenko ◽  
Maria Valeryevna Ryzhkova ◽  
Dmitry Anatolyevich Tsukanov

Bulk β-PdBi2 layered material is known as a low-temperature superconductor. Recently, ultrathin films of this material consisting of dozens of triple layers were grown by molecular beam epitaxy and demonstrated structural, electronic and superconducting properties similar to those of bulk crystals. In this paper, we showed that thin film of β-PdBi2 can be grown by alternative palladium and bismuth deposition and its electrical conductance was investigated at room temperature in comparison with the conductivity of bulk β - PdBi2.


Author(s):  
C.B. Carter ◽  
D.M. DeSimone ◽  
T. Griem ◽  
C.E.C. Wood

Molecular-beam epitaxy (MBE) is potentially an extremely valuable tool for growing III-V compounds. The value of the technique results partly from the ease with which controlled layers of precisely determined composition can be grown, and partly from the ability that it provides for growing accurately doped layers.


Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.


Sign in / Sign up

Export Citation Format

Share Document