Sb Layers Research Articles

DFT study of Sb layers on the Mo(112) surface

Relativistic DFT calculations, performed for Sb layers adsorbed on the Mo (112) surface, have revealed a strong interaction of Sb adatoms with the surface. At low coverages, the layer is predicted to form a c (2 × 2) structure, while for a complete Sb monolayer the most favorable structure is the p (1 × 1), which forms despite a minor one-dimensional compressing of the layer in the direction along the Mo (112) surface furrows. This structure is favorable also for complete bilayer and 3-layer films, so that very thin Sb layers reproduce the furrowed structure of the Mo (112) surface. The adsorbed Sb layers cause a significant redistribution of the densities of states, which, however, does not increase enough at the Fermi level to produce any substantial metallization of the film. The spin-orbit coupling causes only minor changes in the band structure, while Sb layer on one face of the Mo (112) slab destroys the inversion symmetry of the adsorption system thus leading to the appearance of the Rashba-type splitting of the bands.

Uncovering the physical properties, structural characteristics, and electronic application of superlattice-like Ti/Sb phase-change thin films

Superlattice-like (SLL) Ti/Sb thin films were proposed and investigated from the viewpoint of physical properties, structural characteristics, and electronic application. Magnetron sputtering was employed to deposit the SLL Ti/Sb thin films with different thickness ratios. In-situ resistance–temperature measurement indicates that the crystallization temperature, crystallization-activation energy, and data-retention capacity increase significantly and the resistance drift index reduces with an increment in thickness ratio of the Ti to Sb layer, meaning higher amorphous thermal stability and reliability of SLL Ti/Sb thin films. X-ray diffraction and Raman spectra reveal that the inserted Ti layer can inhibit grain growth and refine the grain size, causing remarkable improvement of thermal stability and crystalline resistance. Analyses of x-ray reflectivity and atomic force microscopy demonstrate that the thickness fluctuation of SLL Ti/Sb thin films becomes smaller and the surface topography becomes smoother, respectively. The Avrami exponent of the SLL (Ti3Sb7)5 thin film reflects the growth-dominated crystallization mechanism, implying a rapid phase transition speed. Phase-change memory cells based on the SLL (Ti3Sb7)5 thin film can realize a reversible SET/RESET operation under an electrical pulse with a width of 100 ns. The RESET power consumption was estimated to be much lower than that of traditional Ge2Sb2Te5 material. The above results strongly prove that the suitable SLL structure of Ti/Sb thin films have tremendous potential in the area of high-temperature and low-power electronic storage.

Toward tunable quantum transport and novel magnetic states in Eu1−xSrxMn1−zSb2 (z < 0.05)

Magnetic semimetals are very promising for potential applications in novel spintronic devices. Nevertheless, realizing tunable topological states with magnetism in a controllable way is challenging. Here, we report novel magnetic states and the tunability of topological semimetallic states through the control of Eu spin reorientation in Eu1−xSrxMn1−zSb2. Increasing the Sr concentration in this system induces a surprising reorientation of noncollinear Eu spins to the Mn moment direction and topological semimetallic behavior. The Eu spin reorientations to distinct collinear antiferromagnetic orders are also driven by the temperature/magnetic field and are coupled to the transport properties of the relativistic fermions generated by the 2D Sb layers. These results suggest that nonmagnetic element doping at the rare earth element site may be an effective strategy for generating topological electronic states and new magnetic states in layered compounds involving spatially separated rare earth and transition metal layers.

Thickness-Dependent Crystallization of Ultrathin Antimony Thin Films for Monatomic Multilevel Reflectance and Phase Change Memory Designs.

Phase change materials, with more than one reflectance and resistance states, have been a subject of interest in the fields of phase change memories and nanophotonics. Although most current research focuses on rather complex phase change alloys, e.g., Ge2Sb2Te5, recently, monatomic antimony thin films have aroused a lot of interest. One prominent attractive feature is its simplicity, giving fewer reliability issues like segregation and phase separation. However, phase transformation and crystallization properties of ultrathin Sb thin films must be understood to fully incorporate them into future memory and nanophotonics devices. Here, we studied the thickness-dependent crystallization behavior of pulsed laser-deposited ultrathin Sb thin films by employing dynamic ellipsometry. We show that the crystallization temperature and phase transformation speed of as-deposited amorphous Sb thin films are thickness-dependent and can be precisely tuned by controlling the film thickness. Thus, crystallization temperature tuning by thickness can be applied to future memory and nanophotonic devices. As a proof of principle, we designed a heterostructure device with three Sb layers of varying thicknesses with distinct crystallization temperatures. Measurements and simulation results show that it is possible to address these layers individually and produce distinct and multiple reflectance profiles in a single device. In addition, we show that the immiscible nature of Sb and GaSb could open up possible heterostructure device designs with high stability after melt-quench and increased crystallization temperature. Our results demonstrate that the thickness-dependent phase transformation and crystallization dynamics of ultrathin Sb thin films have attractive features for future memory and nanophotonic devices.

Reducing the formation of Sb2O3 phase and selenium vacancy in Sb2Se3 thin film solar cells via hydrogen-assisted selenization

In this study, we investigated the influence of Sb 2 O 3 or selenium vacancies (V se ) on the characteristics of Sb 2 Se 3 films, and developed a novel hydrogen-assisted selenization (HAS) scheme aimed at reducing the formation of Sb 2 O 3 and V se in the absorber layer of Sb 2 Se 3 solar cells. In experiments, subsurface Sb 2 O 3 formation was more pronounced in RF samples than in DC samples. An Sb 2 Se 3 absorber prepared using RF sputtering without HAS converted from p-type conductivity to n-type conductivity, which reduced the J SC values and device efficiency. Furthermore, the Sb 2 O 3 phase that formed on the surface of the Sb 2 Se 3 film acted as a channel for current flow, which greatly increased current leakage at p-n junction interfaces. Our results indicate that the formation of Sb 2 O 3 phase can lead to a Se-poor state, resulting in the formation of V Se defects in the Sb 2 Se 3 absorber layer, with a corresponding decrease in Jsc. The HAS process was shown to reduce the formation of Sb 2 O 3 and V se in the Sb 2 Se 3 absorber, resulting in device efficiency of 6.16% and Jsc of 27.57 mA/cm 2 , the highest ever recorded for Sb 2 Se 3 thin film solar cells prepared via sputtering. • A novel HAS system to reduce the formation of Sb 2 O 3 phase in Sb 2 Se 3 films. • Sb 2 O 3 formation was shown to promote the formation of V Se in the Sb 2 Se 3 subsurface and reduce Jsc. • Sb 2 O 3 acts as a current channel increasing current leakage at the p-n junction interface. • The proposed HAS process achieved Jsc of 27.57 mA/cm 2 and device efficiency of 6.16%.

Band structure of free Sb layers and spin-orbit splitting of surface bands

As follows from performed DFT calculations, a semimetal state of the bulk Sb crystal results from a spontaneous coupling of neighboring layers. The related decrease of DOS in vicinity of Fermi level, in turn, may be considered as the driving force of the coupling and formation of the characteristic bilayer structure of Sb crystal. The same mechanism of structural transformations is pertinent also to Sb films, built from several hexagonal monolayers. In particular, the coupling leads to semimetallic properties of films built from even number of Sb(111) monolayers, while the films with an odd number of monolayers are strongly metallic, with a high density of states at Fermi level. This feature can be used to control the surface electronic structure by deposition of the proper number of Sb monolayers onto appropriate substrate. Hydrogen monolayer on one face of the Sb(111) film leads to the spin-orbit splitting of the bands.

Toward Hydrogen-Free and Dendrite-Free Aqueous Zinc Batteries: Formation of Zincophilic Protective Layer on Zn Anodes.

Rechargeable aqueous Zn‐ion batteries (ZIBs) are regarded as one of the most promising devices for the next‐generation energy storage system. However, the uncontrolled dendrite growth on Zn metal anodes and the side hydrogen evolution reaction, which has not yet been well considered, hinder the practical application of these batteries. Herein, a uniform and robust metallic Sb protective layer is designed based on the theoretic calculation and decorated on Zn plate via in situ replacement reaction. Compared with the bare Zn plate, the as‐prepared Zn@Sb electrode provides abundant zincophilic sites for Zn nucleation, and homogenizes the electric field around the Zn anode surface, both of which promote the uniform Zn deposition to achieve a dendrite‐free morphology. Moreover, the Gibbs free energy (∆G H) calculation and in situ characterization demonstrate that hydrogen evolution reaction can be effectively suppressed by the Sb layer. Consequently, Sb‐modified Zn anodes exhibit an ultralow voltage hysteresis of 34 mV and achieve excellent cycling stability over 1000 h with hydrogen‐ and dendrite‐free behaviors. This work provides a facile and effective strategy to suppress both hydrogen evolution reaction and dendrite growth.

Sulfurization of Electrodeposited Sb/Cu Precursors for CuSbS2: Potential Absorber Materials for Thin-Film Solar Cells

CuSbS2, as a direct bandgap semiconductor, is a promising candidate for fabricating flexible thin-film solar cells due to its low grain growth temperature (300°C–450°C). Uniform and highly crystalline CuSbS2 thin films are crucial to improving device performance. However, uniform CuSbS2 is difficult to obtain during electrodeposition and post-sulfurization due to the “dendritic” deposition of Cu on Mo substrates. In this study, Sb/Cu layers were sequentially pulse electrodeposited on Mo substrates. By adjusting the pulse parameters, smooth and uniform Sb layers were prepared on Mo, and a flat Cu layer was obtained on Sb without any dendritic clusters. A two-step annealing process was employed to fabricate CuSbS2 thin films. The effects of temperature on phases and morphologies were investigated. CuSbS2 thin films with good crystallinity were obtained at 360°C. As the annealing temperature increased, the crystallinity of the films decreased. The CuSbS2 phase transformed into a Cu3SbS4 phase with the temperature increase to 400°C. Finally, a 0.90% efficient solar cell was obtained using the CuSbS2 thin films annealed at 360°C.

Spin transport in fully ferromagnetic p–n junctions

We systematically investigate the spin-dependent transport properties of fully ferromagnetic (Ga,Fe)Sb/GaSb/(In,Fe)Sb and (Ga,Fe)Sb/(In,Fe)As p–n junctions grown by low-temperature molecular beam epitaxy. The (Ga,Fe)Sb/GaSb/(In,Fe)Sb p–n junctions show high Curie temperature (170–310 K) and rectifying characteristics. The polarity and magnitude of magnetoresistance of the (Ga,Fe)Sb/GaSb/(In,Fe)Sb junctions strongly depend on the GaSb spacer thickness (t). Large positive magnetoresistance (MR, 58%) and negative MR (−1.6%) were observed at 3.7 K for the samples with t = 2 and 4 nm, respectively. When the n-type (In,Fe)Sb layer was replaced by the n-type (In,Fe)As, giant MR over 500% was observed, which can be explained by spin-valve and spin-splitting effects. Our results shed light on rich spin-transport physics observed in fully ferromagnetic p–n junctions.

Galvanically replaced artificial interfacial layer for highly reversible zinc metal anodes

Interface modification is considered as a straightforward strategy to regulate the electrochemical environment of metal anodes and to provide a physically protective interphase. Herein, we develop galvanically replaced artificial interfacial layers, where Sn, Sb, and Bi layers are uniformly grown on Zn anodes, for use in high-performance aqueous rechargeable zinc batteries. The corrosion and dendrite formation of Zn metal are inhibited by manipulating the uniform Zn deposition behavior and facile plating/stripping, as verified by electrochemical characterizations and postmortem, in situ optical, and computational analyses. Considering that the thickness, morphology, and crystallinity of the interfacial layers vary depending on their chemical identity, the Sn modified Zn anode (Zn|Sn) exhibits the optimum electrochemical performance owing to its highest Zn affinity and hierarchical structure. Consequently, symmetric cells with Zn|Sn anodes demonstrate stable plating/stripping over 2200 h at 1 mA cm−2 and a long cycle life of 2000 h at a high current density of 4 mA cm−2. In particular, the full cells by pairing Zn|Sn with β-MnO2 deliver a high capacity of 92.8 mA h g−1 even at a high current rate of 5000 mA g−1, 73% capacity retention after 1000 cycles at 1000 mA g−1, and improved cycle stability under low N/P ratio (&amp;lt;50) and high cathode mass loading (∼15.8 mg cm−2).

Growth and characterization of quaternary-alloy ferromagnetic semiconductor (In,Ga,Fe)Sb

We study the growth and properties of the quaternary-alloy ferromagnetic semiconductor (In0.94−x,Gax,Fe0.06)Sb (x = 5%–30%; the Fe concentration is fixed at 6%) grown by low-temperature molecular beam epitaxy. Reflection high-energy electron diffraction patterns, scanning transmission electron microscopy lattice images, and x-ray diffraction spectra indicate that the (In0.94−x,Gax,Fe0.06)Sb layers have a zinc blende crystal structure without any other second phase. The lattice constant of the (In0.94−x,Gax,Fe0.06)Sb films changes linearly with the Ga concentration x, indicating that Ga atoms substitute In atoms in the zinc-blende structure. We found that the carrier type of (In0.94−x,Gax,Fe0.06)Sb can be systematically controlled by varying x, being n-type when x ≤ 10% and p-type when x ≥ 20%. Characterization studies using magnetic circular dichroism spectroscopy indicate that the (In0.94−x,Gax,Fe0.06)Sb layers have intrinsic ferromagnetism with relatively high Curie temperatures (TC = 40–120 K). The ability to widely control the fundamental material properties (lattice constant, bandgap, carrier type, and magnetic property) of (In0.94−x,Gax,Fe0.06)Sb demonstrated in this work is essential for spintronic device applications.

Theoretical study of stability, epitaxial formation, and phase transformations of two-dimensional pnictogen allotropes

We present a theoretical study of the thermodynamical factors that determine epitaxial formation of single layer 2D pnictogen (P, As, Sb, Bi) allotropes on substrates of any type. The interplay of substrate-adlayer interaction and strain induced by epitaxial matching is analyzed in terms of the phase diagram describing growth during the gaseous deposition stage. The necessary conditions to favor particular allotrope growth (in particular, the $\ensuremath{\alpha}$ and $\ensuremath{\beta}$ phases) are determined. We show that buckled Sb and Bi layers can overcome large tensile strain and form flat honeycomb layers even on common metal surfaces. An alternative strategy for controlled allotrope formation via thermally induced phase transformations between $\ensuremath{\alpha}$ and $\ensuremath{\beta}$ phases is examined in detail, including important methodological analysis. All four elements follow reconstructive transition pathways, whose activation barrier correlates with the bond dissociation energy. If nucleation is considered, the barrier can further reduce by about 13% and thus becomes quite accessible under typical annealing conditions. The role of van der Waals and spin-orbit corrections in the stability of several allotropes is carefully addressed. The theoretical insight gained is evaluated in light of experimental reports and strategies for controlling growth are outlined.

Insertion of Magnesium into Antimony Layers on Gold Electrodes:Kinetic Behaviour

AbstractMagnesium based secondary batteries are regarded as a viable alternative to the immensely popular Li‐ion systems. One of the largest challenges is the selection of a Mg anode material since the insertion/extraction processes are kinetically slow because of the large ionic radius and high charge density of Mg2+. In an attempt to bridge the gap between insertion measurements in 3D composite electrode materials and that in an idealized pure model system, we studied the insertion and diffusion of Mg in a thin, massive layer of Sb deposited on Au by using PITT, CV, and potential step experiments. Sb has been suggested as an insertion material because magnesium can form intermetallic compound with it. The layered crystal structure of Sb leads should facilitate formation of such an intermetallic phase. Mg insertion from a MACC/tetraglyme electrolyte into Sb starts 300 mV positive of the onset potential of Mg deposition as shown by cyclic voltammetry. The molar ratio of Mg to Sb agrees well with the stoichiometry of Mg3Sb2 alloy (Zintl‐phase). The diffusion coefficient of Mg‐insertion into Sb – layers and the charge transfer rate have been estimated by the above techniques. Such diffusion coefficients, albeit still somewhat “apparent”, are much more closely related to the true diffusion coefficient in the metal or alloy. The solid‐state diffusion coefficient of Mg into the Sb layers is in the range of 4–8×10−14 cm2 s−1. A very high Tafel slope of 370 mV/dec was found in potential step experiments. Mg insertion was further investigated by XPS measurements. Besides Mg and Sb, Al and Cl signals were also detected, particularly at the outer parts of the layer.

Facile surface treatment of precursors before rapid melt growth of GaSb on silicon

The efficient monolithic III-V integration on silicon (Si) substrates can leverage the excellent optoelectronic properties of III-V semiconductors and the Si microfabrication technology for electronic, optoelectronics, integrated photonics devices. However, the origin of the interfacial and material defects during III-V monolithic integration on Si poses the challenge to achieve efficient optical emitters, detectors. In this study, we investigated different surface treatment schemes before rapid melt growth (RMG) of GaSb on Si substrate to attain defect control. The deposition of an Sb layer (10 nm) on GaSb precursors surfaces resulted in achieving better structural and optical properties of GaSb post RMG. We achieved a reduction of 2.48 atomic % of unintentional incorporation of Si into the GaSb via Sb treatment compared to that of untreated GaSb analysed using transmission electron microscopy and energy-dispersive X-ray spectroscopy. Improved surface morphology with reduced root mean square roughness of 3.7 nm is obtained with Sb layer treatment compared to 5.6 nm for untreated GaSb precursor measured by atomic force microscopy. We obtained improved optical properties and low defect density with an in-situ Sb treatment scheme on GaSb precursor surface by µ-Photoluminescence and µ-Raman spectroscopy analysis.

Investigation of Calcium Alloying with Sb, Sn and Bi As Negative Electrode Materials for Rechargeable Calcium Battery in Non-Aqueous Electrolytes

Alloys were suggested as alternative anode materials for Ca metal anode because they have a high specific capacity and low overpotential. [1] A DFT study of CaxM has suggested a variety of alloy-type anode materials and considered the alloying voltage, volume expansion, and specific capacity. The metals such as Si, Sb, Bi, Al, Pt, Pb, and so on were predicted to be promising inexpensive anode candidates. [1] An Sn Nano-particular with a thickness of 25 μm was investigated for both the anode and current collector using 0.8 M Ca(PF6)2 in EC:PC:DMC:EMC (2:2:3:3) electrolytes. [2] It’s showed a high and wide voltage window (up to 4.8 V) and the cell could be cycled more than 300 cycles. The alloying compounds were found to be different phases with finally Ca7Sn6.In this work, we study the fundamentals of the alloying process alloying of Ca thin film of bulk Sb, Sn, and Bi on polycrystalline Au using non-aqueous electrolyte (1.5 M Ca(BH4)2 in THF) at room temperature. Calcium stripping and plating using a Ca(BH4)2 in THF electrolyte shows high Coulombic efficiency (95 %) at room temperature on an Au substrate. [3] The cycling reversibility of alloying/de-alloying with Sb, Sn, and Bi have been demonstrated. The cyclic voltammogram for Ca insertion/de-insertion into Sb, Sn, and Bi-modified electrode shows a positive shift of the onset potential of Ca deposition compared to that at bare Au electrode. The ratio of moles of Ca to Sb, Sn, and Bi agrees with the stoichiometry of CaSb2, CaSn2, and CaBi3 alloy. Potential step were used to study the kinetics of insertion. The diffusion coefficient of Ca into the Sb, Sn, and Bi layers is calculated to be 10−14 \U0001d461\U0001d45c 10−15 cm2s-1. Acknowledgments: The authors acknowledge funding by the Federal Ministry of Education and Research of Germany (BMBF, FKZ; 03EK3027A).[1] Z. Yao, V. I. Hegde, A. Aspuru-Guzik, and C. Wolverton, Advanced Energy Materials 9:1802994 (2019).[2] N. Z. Wu, W. J. Yao, X. H. Song, G. Zhang, B. J. Chen, J. H. Yang, and Y. B. Tang, Advanced Energy Materials 9:7 (2019).[3] D. Wang, X. Gao, Y. Chen, L. Jin, C. Kuss, and P. G. Bruce, Nature Materials 17:16 (2017).

Evolution of Topological Surface States Following Sb Layer Adsorption on Bi2Se3.

Thin antimony layers adsorbed on bismuth selenide () present an exciting topological insulator system. Much recent effort has been made to understand the synthesis and electronic properties of the heterostructure, particularly the migration of the topological surface states under adsorption. However, the intertwinement of the topological surface states of the pristine substrate with the Sb adlayer remains unclear. In this theoretical work, we apply density functional theory (DFT) to model heterostructures of single and double atomic layers of Sb on a bismuth selenide substrate. We thereby discuss established and alternative structural models, as well as the hybridization of topological surface states with the Sb states. Concerning the geometry, we reveal the possibility of structures with inverted Sb layers which are energetically close to the established ones. The formation energy differences are below 10 meV/atom. Concerning the hybridization, we trace the band structure evolution as a function of the adlayer-substrate distance. By following changes in the connection between the Kramers pairs, we extract a series of topological phase transitions. This allows us to explain the origin of the complex band structure, and ultimately complete our knowledge about this peculiar system.

The coupling effect and phase transition behavior of multiple interfaces in GeTe/Sb superlattice-like films

In this paper, the phase transition mechanism and device conversion performance of the Sb/GeTe superlattice-like films were studied and showed improved amorphous thermal stability and resistance drift compared to the pure Sb films. Transmission electron microscopy showed that the Sb layer plays a leading role in the crystallization process, forming a large number of Sb grains. The metallic behavior of the Sb/GeTe thin films was confirmed by density functional theory calculations. The thermal conductivity of the crystalline film was found to be higher than that of the amorphous film, and the thermal conductivity of the Sb/GeTe film was lower than that of the other monolayer films. In the Sb/GeTe film, the Sb–Sb and Ge–Te bonds were the main bond structures, and some Sb–Te bonds were formed at the layer interfaces, enhancing the stability of the film. Laser picosecond measurements showed that Sb/GeTe film had a higher crystallization rate than the GeTe film. The phase change memory devices based on the Sb/GeTe thin films were found to have lower operational power consumption and higher transition speed. These results showed that the Sb/GeTe thin film explored in this study was a promising phase change storage thin film with excellent performance.

Properties of Bare and Thin-Film-Covered GaN(0001) Surfaces

In this paper, the surface properties of bare and film-covered gallium nitride (GaN) in wurtzite form, (0001) oriented, are summarized. Thin films of several elements—manganese, nickel, palladium, arsenic, and antimony—were formed by the physical vapor deposition method. The results of the bare surfaces, as well as the thin film/GaN(0001) phase boundaries presented, were characterized by X-ray and ultraviolet photoelectron spectroscopies (XPS, UPS). Basic information on the electronic properties of GaN(0001) surfaces are shown. Different behaviors of the thin films, after postdeposition annealing in ultrahigh vacuum conditions such as surface alloying and subsurface dissolving and desorbing, were found. The metal films formed surface alloys with gallium (MnGa, NiGa, PdGa), while the semimetal (As, Sb) layers easily evaporate from the GaN(0001) surface. However, the layer in direct contact with the substrate could react with it, modifying the surface properties of GaN(0001).

Dipole control of Rashba spin splitting in a type-II Sb/InSe van der Waals heterostructure

InSe monolayer, belonging to group III–VI chalcogenide family, has shown promising performance in the realm of spintronic. Nevertheless, the out-of-plane mirror symmetry in InSe monolayer constrains the electrons' degrees of freedom, and this will confine its spin-related applications. Herein, we construct Sb/InSe van der Waals heterostructure to extend the electronic and spintronic properties of InSe. The density functional theory is utilized to verify the tunable electronic properties and Rashba spin splitting (RSS) of Sb/InSe heterostructure. According to the obtained results, the Sb/InSe heterostructure can be considered as a direct band gap semiconductor with typical type-II band alignment, where the electrons and holes are localized in the InSe and Sb layers, respectively. The RSS is recognized at conduction band minimum around Γ point in Sb/InSe, which is induced by the spontaneous internal electric field with electric dipole moment of 0.016 e Å from Sb to InSe. The vertical strain, in-plane strain, and external electric field are employed to modulate the strength of RSS. The Rashba coefficient and dipole moment exhibit the similar variation tendency, suggesting the strength of RSS depends on the magnitude of dipole moment. The controllable RSS makes Sb/InSe heterostructure become an appropriate candidate material for spintronic devices.

Layer-exchange crystallization for low-temperature (∼450 °C) formation of n-type tensile-strained Ge on insulator

Layer-exchange crystallization of Ge using a group-V element has been investigated to develop a low-temperature (&amp;lt;500 °C) formation technique of n-type tensile-strained crystalline Ge on insulator. Here, the Sb of a group-V element is employed as a catalyst. Annealing (450 °C) of a-Ge (100 nm)/Sb (100 nm) bi-layer stacked structures generates layer-exchange crystallization. Namely, Ge and Sb layers exchange their positions, and Ge layers are crystallized on insulator substrates. However, Ge evaporation occurs during annealing, and a high concentration of Sb (∼20%) remains at the Ge/insulator interface. To solve these problems, the thickness reduction of Sb films and introduction of a-Ge thin under-layers are examined. By annealing (450 °C) a-Ge (100 nm)/Sb (50 nm)/a-Ge (5 nm) tri-layer structures, layer-exchange crystallization of Ge layers on insulator without Ge evaporation or Sb residue has been achieved. This enables formation of n-type tensile-strained (∼0.3%) Ge layers (free electron concentration: ∼5 × 1017 cm−3). Moreover, crystal orientation control of grown Ge films through the introduction of the diffusion barrier is examined. These results demonstrate the possibility of layer-exchange crystallization induced by a group-V element to realize functional thin-film devices for advanced electronics and photonics.