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NANO ENERGY

Volume 83, May 2021, 105790

QUANTUM-CONFINED BLUE PHOTOEMISSION IN STRAIN-ENGINEERED FEW-ATOMIC-LAYER 2D
GERMANIUM

Author links open overlay panelNaveed Hussain a b 1, Yao Yisen a 1, Rizwan Ur
Rehman Sagar d, Tauseef Anwar d f, Muhammad Murtaza b, Kai Huang c, Khurrum
Shehzad e, Hui Wu b, Zhiming Wang a
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HIGHLIGHTS

* •

Technological advancements of germanium in optoelectronics have remained
restricted due to its indirect bandgap (0.67 eV).

* •

Realization of Ge in ultrathin 2D crystals with strain-engineered lattice can
exhibit remarkable property modulation.

* •

A vacuum-tube hot-pressing (VT-HP) strategy to synthesize strain-engineered
few atomic layer 2D Ge has been introduced.

* •

Coefficient of thermal expansion mismatching causeda biaxial compressive
strain of ~1.23 ± 0.06% in 2D Ge lattice.

* •

An ultra-bright 42-fold blue photoemissionin 2D Ge was achieved due to an
indirect to direct bandgap transition (~2.91 eV).

ABSTRACT

The indirect bandgap (0.67 eV) of bulk germanium (Ge) remains a major bottleneck
towards its applications in optoelectronics, enabling poor optical features
particularly photoluminescence. Obtaining desired optical functionalities,
either by synthesizing few-atoms-thick two-dimensional (2D) germanium on
silicon-based substrates, or by inducing an appreciable structural engineering
in its crystal lattice, has long remained a formidable challenge yet to be
mitigated. Herein, a facile vacuum-tube hot-pressing strategy to synthesize
strain-engineered few-atomic-layer 2D germanium nanoplates (Ge-NPts) directly on
fused silica substrate (SiO2) is developed. Leveraging from the unique mismatch
between coefficient of thermal expansion of Ge and SiO2 substrate at elevated
temperatures (700 °C), and under hydrostatic pressure (~2 GPa), a biaxial
compressive strain of ~1.23 ± 0.06% in Ge lattice is engineered, causing a
transition from indirect to direct bandgap with an ultra-large opening of
2.91 eV. Strained Ge nanoplates, consequently, display a remarkable 42-fold blue
photoluminescence (at 300 K) compared to bulk Ge, accompanied by robust
quantum-confinement effects, probed by the quantum-shift ~114 meV with
decreasing thicknesses of Ge nanoplates.

GRAPHICAL ABSTRACT

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INTRODUCTION

The absence of bandgap in graphene [1] has stimulated the surge of new
two-dimensional (2D) semiconductors for electronic and optoelectronics
applications [2], [3], [4], [5], [6]. In this pursuit, tremendous amount of
research has been devoted to intrinsic layered materials (e.g. TMDCs, BP, h-BN
etc.) [7], [8], [9], [10]; however, exotic properties of non-layered-lattice
based materials in 2D-regime have largely remained unexplored, predominantly
because of their extremely challenging isolation in 2D layers by existing
methods. Allotropes of group IVA elements such as germanene [11], [12] and
silicene [13] belong to the family of such non-layered-lattice based 2D
materials that exhibit exceptional (opto)electronic properties [14]. Germanium
(Ge) in particular, is intrinsically an indirect bandgap (0.67 eV) semiconductor
by virtue of its conduction band minima (CBM) and valance band maxima (VBM)
positioned at different momentum space (k). Exceptionally high absorption
coefficient (c.a. 2 × 105 cm−1) and carrier mobility (µh = 1900 cm2 V−1 s−1, µe
= 3900 cm2 V−1 s−1) of Ge make it promising for efficient field effect
transistors [15], near infrared (NIR) photodetection [16], high-speed
photodetectors [17], and non-linear optics [18], [19]. Nevertheless, the most
intriguing property of Ge stems from its comparatively large Bohr exciton radius
rh=εh2/e2m* (where m* = me+mh, me and mh being the effective masses of the
electron and hole) of ~24.3 nm, providing a wide window for observing quantum
confinement effects, offered reduction of dimensionality to the order of Bohr
exciton radius, often termed as quantum limit [20]. Thereupon, 2D-Ge
nanostructures (~z < 15 nm) are poised to exhibit anomalous physical properties,
owing to the restricted pathways offered to phonons, photons and charge carriers
[16], [21], [22]. Furthermore, 2D-Ge is highly anticipated as it not only offers
seamless compatibility with current Si-based technology, but also allows an
opportunity to tune its bandgap, thanks to its favorable armchair-like buckled
structure and large spin-orbit coupling [23].

In 2D regime, responses to external stimuli are strongly coupled with crystal
symmetry and lattice dynamics. Hence, reducing dimensionality is not the only
way to embed enhanced, yet desired functionalities. Strain engineering has
emerged as one exciting technique, where even a slight strain (either
compressive or tensile) in crystal lattice results in significant bandgap
modulation in 2D semiconductors [24]. Strain engineering, reported recently in
2D TMDCs [25], [26], [27], black phosphorous [28], [29], and tellurium [30] has
been demonstrated as an efficient strategy to manipulate atomic and band
structure, leading to tremendously improved electronic and optical properties.
Therefore, strain engineering in 2D-Ge with thicknesses less than Bohr exciton
radius can further impart remarkably improved optical and electronic properties,
in addition to observing quantum effects room-temperature (300 K).

Conventionally, 2D Ge is grown exclusively on metallic (Pt, Au, Al etc.)
substrates by techniques such as molecular beam epitaxy (MBE) [12], [31], [32]
and smart-cut processes [33]. However, these techniques suffer from
inaccessibility, high cost and complex procedures and above all, incompatibility
with Si-based technology due to the hybridization of electronic states between
Ge and metal substrate [34]. Recently, growth of triangular Ge nanoflakes on
Si/SiO2 substrates has been demonstrated by using chemical vapor deposition
(CVD) but with moderate thicknesses ~8.5 nm [16]. To achieve robust quantum
confinement effects and superior (opto)electronic properties at
room-temperature, realizing highly strained 2D-Ge nanostructures with
thicknesses comparable to quantum dots (< 5 nm) is crucial. On top of that,
strained sub-5 nm 2D-Ge grown on ordinary silicon dioxide (SiO2) substrates
offer compatibility with current Si-based technology, and to facilitate optical
investigations.

In the present work, we report a unique and facile vacuum-tube hot-pressing
(VT-HP) strategy; a modified form of conventional hot-pressing method [35],
[36], to realize strain-engineered 2D-Ge nanoplates (Ge-NPts) with sub-5 nm
thicknesses on a low-cost and insulating fused SiO2 substrates. Large area
Ge-NPts with wrinkled surfaces, scattered over several hundred square microns,
each with lateral dimensions spanning few tens of microns were realized. A
localized biaxial compressive strain of 1.23% was introduced by exploiting the
coefficient of thermal expansion (CTE) mismatch between the bulk Ge and SiO2
substrate (probed by µ-Raman investigations) at high temperature (700 °C),
enforced by a large hydrostatic pressure (~2 GPa). We further demonstrate
strain-induced indirect-direct bandgap transition with an ultra-large opening of
2.91 eV in Ge-NPts, exhibited by a robust 42-fold blue photoluminescence (PL)
compared with bulk Ge, accompanied by the quantum-confinement effects at
room-temperature. Such strained-engineered 2D-Ge-NPts are promising candidates
for monolithic integration in to next generation nano-LEDs and nano-lasers
operating in visible region of spectrum.

SECTION SNIPPETS

RESULTS AND DISCUSSION

Thermo-compression synthesis method has recently emerged as a versatile top-down
method, which can yield high quality ultrathin 2D crystals [36]. The schematic
illustration of proposed vacuum-tube hot-pressing (VT-HP) strategy which is a
modified version of conventional hot-pressing method is introduced to achieve
large area and highly strained ultrathin Ge-NPts on fused SiO2 (silica) (Fig.
1A). Homogeneously dispersed micron size Ge particles were dropped on highly
polished SiO2 substrate and

CONCLUSION

We demonstrate a versatile vacuum-tube hot-pressing (VT-HP) strategy to realize
strain-engineered Ge-NPts directly on to SiO2 substrate, which enables them to
be compatible with Si-based technology. The method not only provides pathways to
engineer compressive strain in 2D materials but also facilitates in realizing
non-layered 2D materials that are previously inaccessible by existing
techniques. Comprehensive µ-Raman and XRD investigations revealed a combination
of biaxial compressive strain

MATERIALS

Ge chunks were purchased from Sigma Aldrich (99.99%) and were used without
further purification. Uniformly sized (2 ×2 cm2) SiO2 (fused silica) substrates
with highly polished surfaces were purchased from KYKY Technology Co. LTD. The
substrates were subsequently subjected to repeated thorough cleaning by
repeatedly by an ultrasonicator in acetone, ethanol and distilled water
environments. Stainless steel bars were purchased from local manufacturer in
Beijing. The evacuated glass tube,

FABRICATION OF SUB-5 NM GE-NPTS

Chunks of bulk Ge were grinded in a mortar for 15 min to obtain fairly uniform
micron-sized particles. About 5 mg of grinded powder was dispersed in 30 ml of
ethanol to prepare a homogenous dispersion. Around 100 µL of dispersion was
dropped on SiO2 substrates with dimensions of 2 cm × 2 cm and left it to dry in
Argon filled glove box (MB200MOD) for 20 min. Large agglomerates of dried Ge
microparticles left on the on quartz substrate after the evaporation of ethanol.
The mass-loaded quartz

CALCULATIONS OF STRESS APPLIED BY PRESSURE DEVICE ASSEMBLY

Stress/compression applied on Ge micro-particles via pressure device assembly
was estimated by carefully observing and measuring the modulus of rigidity,
otherwise known as shear strain. The amount of shear strain (Δx) appearing at
four corners of stainless steel bars, as a result of vertical compression
exerted by tightening of screws was measured by micrometer screw gauge.
Considering the known value of the constant of modulus of rigidity (G) for
stainless steel, we used the following

MATERIAL CHARACTERIZATIONS

Structural characterizations of Ge-NPts on SiO2 were performed by using X-ray
diffractometer (Rigaku D/Max 2500), equipped with a graphite monochromator and
Cu Kα radiation (λ = 1.5406 Å) at a scanning rate of 0.020/min in 2θ range of
20–70°. For the measurements, voltage and electric current were fixed at 40 kV
and 30 mA, respectively. Morphology investigations of Ge-NPts were performed by
using field emission scanning electron microscopy (FESEM, MERLIN VP compact,
Carl Zeiss, Germany).

AUTHOR CONTRIBUTIONS

N.H. initiated the project after consultation with H.W. N.H. synthesized and
performed structural characterizations of strained Ge NPts. N.H. fabricated the
samples for optical measurements. Y.Y. performed XRD simulations. N.H. and Z.W.
performed the data analysis. N.H. wrote the manuscript with contributions from
all other authors. N.H., H.W., Z.W. supervised the project.

CREDIT AUTHORSHIP CONTRIBUTION STATEMENT

Naveed Hussain: Conceptualization, Methodology, Experiment, Data curation,
Writing - original draft. Yao Yisen: Software, Writing - review & editing.
Rizwan-Ur-Rehman Sagar: Data Analysis, Writing - review & editing. Tauseef
Anawar: Writing - review & editing. Muhammad Murtaza: Experiments, Logistics.
Huang Kai: Data analysis. Khurram Shahzad: Data analysis, Writing - review &
editing. Hui Wu: Supervision, Funds allocation. Zhiming Wang: Supervision,
Writing - review & editing, Funds allocation.

DECLARATION OF COMPETING INTEREST

The authors declare that they have no known competing financial interests or
personal relationships that could have appeared to influence the work reported
in this paper.

ACKNOWLEDGEMENTS

Funding Sources: This study was jointly supported by the National Key Research
and Development Program (No. 2019YFB2203400), the National Basic Research of
China (Grants 2015CB932500, 2016YFE0102200 and 2018YFB0104404) and National
Natural Science Foundation of China (Grants 51788104, 51661135025, 51706117 and
U1564205).

Dr. Naveed Hussain earned his PhD in 2019 from School of Materials, Tsinghua
university, Beijing, China, under the supervision of Dr. Hui Wu. Before that, he
obtained his Master’s degree in Physics (2010-2012) from International Islamic
University, Islamabad, Pakistan. Currently, he is working as a postdoctoral
research fellow with prof. Zhiming Wang at Institute of Fundamental and Frontier
Sciences (IFFS), University of Electronic Science and Technology of China,
Chengdu, Sichuan, China. His

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REFERENCES (63)

* D. Carolan

RECENT ADVANCES IN GERMANIUM NANOCRYSTALS: SYNTHESIS, OPTICAL PROPERTIES AND
APPLICATIONS

PROG. MATER. SCI.

(2017)
* A.N. Kholod et al.

OPTICAL PROPERTIES OF GE AND SI NANOSHEETS––CONFINEMENT AND SYMMETRY EFFECTS

SURF. SCI.

(2003)
* Z. Li et al.

EFFICIENT STRAIN MODULATION OF 2D MATERIALS VIA POLYMER ENCAPSULATION

NAT. COMMUN.

(2020)
* T. Akatsu et al.

GERMANIUM-ON-INSULATOR (GEOI) SUBSTRATES—A NOVEL ENGINEERED SUBSTRATE FOR
FUTURE HIGH PERFORMANCE DEVICES

MATER. SCI. SEMICOND. PROCESS.

(2006)
* D.A. Muzychenko et al.

ATOMIC INSIGHTS INTO SINGLE LAYER AND BILAYER GERMANENE ON AL (111) SURFACE

MATER. TODAY PHYS.

(2020)
* R.R. Reeber et al.

THERMAL EXPANSION AND LATTICE PARAMETERS OF GROUP IV SEMICONDUCTORS

MATER. CHEM. PHYS.

(1996)
* K. Prabhakaran et al.

OXIDATION OF GE (100) AND GE (111) SURFACES: AN UPS AND XPS STUDY

SURF. SCI.

(1995)
* Q. Yao et al.

MICROWAVE-ASSISTED SYNTHESIS AND CHARACTERIZATION OF BI2TE3 NANOSHEETS AND
NANOTUBES

J. ALLOY. COMPD.

(2009)
* M. Dubiel et al.

ON THE STRESS STATE OF SILVER NANOPARTICLES IN ION-IMPLANTED SILICATE GLASSES

NUCL. INSTRUM. METHODS PHYS. RES. SECT. B BEAM INTERACT. MATER. ATOMS

(2000)
* A. Zunger et al.

THEORY OF SILICON NANOSTRUCTURES

APPL. SURF. SCI.

(1996)

K.S. Novoselov et al.

ELECTRIC FIELD EFFECT IN ATOMICALLY THIN CARBON FILMS

SCIENCE

(2004)
D. Akinwande et al.

TWO-DIMENSIONAL FLEXIBLE NANOELECTRONICS

NAT. COMMUN.

(2014)
K.F. Mak et al.

PHOTONICS AND OPTOELECTRONICS OF 2D SEMICONDUCTOR TRANSITION METAL
DICHALCOGENIDES

NAT. PHOTON

(2016)
F. Xia et al.

REDISCOVERING BLACK PHOSPHORUS AS AN ANISOTROPIC LAYERED MATERIAL FOR
OPTOELECTRONICS AND ELECTRONICS

NAT. COMMUN.

(2014)
X. Chen et al.

GRAPHENE HYBRID STRUCTURES FOR INTEGRATED AND FLEXIBLE OPTOELECTRONICS

ADV. MATER.

(2019)
K. Shehzad et al.

DESIGNING AN EFFICIENT MULTIMODE ENVIRONMENTAL SENSOR BASED ON GRAPHENE–SILICON
HETEROJUNCTION

ADV. MATER. TECHNOL.

(2017)
H. Ramakrishna Matte et al.

MOS2 AND WS2 ANALOGUES OF GRAPHENE

ANGEW. CHEM. INT. ED.

(2010)
B. Radisavljevic et al.

SINGLE-LAYER MOS2 TRANSISTORS

NAT. NANOTECHNOL.

(2011)
L.H. Li et al.

ATOMICALLY THIN BORON NITRIDE: UNIQUE PROPERTIES AND APPLICATIONS

ADV. FUNCT. MATER.

(2016)
L.H. Li et al.

STRONG OXIDATION RESISTANCE OF ATOMICALLY THIN BORON NITRIDE NANOSHEETS

ACS NANO

(2014)
A. Acun et al.

GERMANENE: THE GERMANIUM ANALOGUE OF GRAPHENE

J. PHYS. CONDENS. MATTER

(2015)
M. Dávila et al.

GERMANENE: A NOVEL TWO- DIMENSIONAL GERMANIUM ALLOTROPE AKIN TO GRAPHENE AND
SILICENE

NEW J. PHYS.

(2014)
P. Vogt et al.

SILICENE: COMPELLING EXPERIMENTAL EVIDENCE FOR GRAPHENELIKE TWO- DIMENSIONAL
SILICON

PHYS. REV. LETT.

(2012)
P. Goley et al.

GERMANIUM BASED FIELD-EFFECT TRANSISTORS: CHALLENGES AND OPPORTUNITIES

MATERIALS

(2014)
A.B. Greytak et al.

GROWTH AND TRANSPORT PROPERTIES OF COMPLEMENTARY GERMANIUM NANOWIRE FIELD-EFFECT
TRANSISTORS

APPL. PHYS. LETT.

(2004)
X. Hu et al.

HALIDE-INDUCED SELF-LIMITED GROWTH OF ULTRATHIN NONLAYERED GE FLAKES FOR
HIGH-PERFORMANCE PHOTOTRANSISTORS

J. AM. CHEM. SOC.

(2018)
L. Chen et al.

ULTRA-LOW CAPACITANCE AND HIGH SPEED GERMANIUM PHOTODETECTORS ON SILICON

OPT. EXPRESS

(2009)
B.-U. Sohn et al.

KERR NONLINEARITY AND MULTI- PHOTON ABSORPTION IN GERMANIUM AT MID-INFRARED
WAVELENGTHS

APPL. PHYS. LETT.

(2017)
G. Grinblat et al.

ENHANCED THIRD HARMONIC GENERATION IN SINGLE GERMANIUM NANODISKS EXCITED AT THE
ANAPOLE MODE

NANO LETT.

(2016)
L. Seixas et al.

QUANTUM SPIN HALL EFFECT ON GERMANENE NANOROD EMBEDDED IN COMPLETELY
HYDROGENATED GERMANENE

PHYS. REV. B

(2014)
S. Assefa et al.

REINVENTING GERMANIUM AVALANCHE PHOTODETECTOR FOR NANOPHOTONIC ON-CHIP OPTICAL
INTERCONNECTS

NATURE

(2010)
View more references

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Yisen Yao obtained his B.E degree from University of Electronic Science and
Technology of China. He is a Ph.D. candidate in Prof. Zhiming Wang group at
Institute of Fundamental and Frontier Sciences, university of Electronic Science
and Technology of China. His research interest focuses on designing of 2D
materials and perovskites for excellent Photo-Electronic properties,
half-metallicity and ferromagnetic properties.

Rizwan Ur Rehman Sagar is working as Associate Professor in Jiangxi University
of Science and Technology, Ganzhou, China. He has finished his PhD (2015) from
the world’s prestigious Tsinghua University and he also served as an excellent
postdoctoral fellow of Tsinghua University. His research focuses on the
transport properties of low-dimensional materials (2D-Materials, Topological
Insulators), photon-based applications (Photodetectors and upconversion
mechanism-based devices), and advanced energy devices (Lithium-ion batteries and
hydrogen fuel cells).

Dr Tauseef Anwar is obtained his PhD from School of Materials Science and
Engineering, Tsinghua University Beijing in 2017. He served as assistant
professor in COMSATS University Islamabad and University of the Lahore,
Pakistan. Currently, he is working as an Associate Professor in College of Rare
Earths, Jiangxi University of Science and Technology. His research focuses on
key materials and technology for energy applications, aiming to enhance the
performances of materials by tuning their structure and surface/interface
chemistry, on the basis of investigation on the correlations among
surface/interface chemistry, synthesis and performances of the materials.

Muhammad Murtaza obtained his bachelor in science (B.Sc) from Islamia college
Peshawar Pakistan. He completed his M.sc and M.Phil in physics from Quaid-I-Azam
university, Islamabad Pakistan. Currently, he is a PhD candidate in Prof. Hui
Wu’s group at Tsinghua university, Beijing, China. His research interests
include synthesis of metallic nanostructures, characterization and fabrication
of conductive ink materials.

Dr. Kai Huang received his B.S. degree in 2011 and Ph.D. degree in School of
Science, Beijing University of Posts and Telecommunications in 2016. After
postdoc research in Prof. Dr. Hui Wu's group at Tsinghua University (2016–2018),
he became an Associate Professor at School of Science in Beijing University of
Posts and Telecommunications. His research interest focuses on design, synthesis
and application exploration of advanced functional single-atom, sub-nano and
ultrathin two-dimensional materials.

Dr. Khurram Shehzad obtained his PhD in Materials Science and Engineering in
2011 from Beijing University of Chemical Technology. From 2011–2013, he was a
postdoctoral fellow at centre for nano and micro mechanics, Tsinghua University.
He Joined Zhejiang University as a postdoctoral fellow in 2014. Currently, he is
a working as an Associate Professor of Research at College of Information
Science and Electronic Engineering. He is also adjunct faculty at Zhejiang
University-University of Illinois at Urbana-Champaign Joint Institute and
associated faculty at Zhejiang University-Hangzhou Global Scientific and
Technological Innovation Centre.

Dr. Hui Wu received his B.E. degree in 2004 and Ph.D. degree in 2009 from
Tsinghua University. After postdoc research in Prof. Yi Cui's group at Stanford
University (2009–2013), he became an Associate Professor at School of Materials
Science and Engineering in Tsinghua University. He has received academic honors
and awards including 1000 Talents Program for Young Scholars, National
Outstanding Doctoral Dissertation Award, Chief Youth Scientist of National 973
Program, National Natural Science Funds for Outstanding Young Scholar and TR35.
His research interest focuses on materials for energy storage and conversion,
advanced functional ceramic materials, flexible electronics materials.

Dr. Zhiming Wang is a Professor of National Distinguished Experts at University
of Electronic Science and Technology of China (UESTC). He received his B.S. in
Applied Physics from Qingdao University (1992), M.S. in Physics from Peking
University (1995), and Ph.D. in Condensed Matter Physics from the Chinese
Academy of Sciences (1998). He is a Fellow of the Royal Society of Chemistry
(RSC), Fellow of the Institute of Physics (IoP), Fellow of the Institute of
Materials, Minerals and Mining (IMMM) and Fellow of the Institution of
Engineering and Technology (IET). His research interests include the rational
design of low-dimensional semiconductor nanomaterials for optoelectronic
applications

These authors contributed equally to this work.

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