Ultrathin and Flat Layer Black Phosphorus Fabricated by Reactive Oxygen and Water Rinse

Kwon, Hyuk‐Sang; Seo, Sung Won; Kim, Tae Gun; Lee, Eun Seong; Lanh, Phung Thi; Yang, Sena; Ryu, Sunmin; Kim, Jeong Won

doi:10.1021/acsnano.6b04194

Cited by 75 publications

(69 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Graphene's 4 absence of bandgap hinders its application in logic devices, even though the bandgap can be somehow tuned 5,6 . Although layered black phosphate has been shown to possess a unique ambipolar property 7 , it hardly survives after several hours of exposure in the atmosphere due to the low reactive barrier between black phosphate and oxygen/water [8][9][10] . Recently, transition metal dichalcogenides (MX 2 , where M = group IVB-VIIB metal and X = chalcogen) with a layered crystal structure were demonstrated to exhibit excellent semiconducting electrical properties with a large on/off ratio [11][12][13][14] .…”

Section: Introductionmentioning

confidence: 99%

The ambipolar transport behavior of WSe2 transistors and its analogue circuits

et al. 2018

View full text Add to dashboard Cite

Tungsten diselenide (WSe 2 ) has many excellent properties and provides superb potential in applications of valleybased electronics, spin-electronics, and optoelectronics. To facilitate the digital and analog application of WSe 2 in CMOS, it is essential to understand the underlying ambipolar hole and electron transport behavior. Herein, the electric field screening of WSe 2 with a thickness range of 1-40 layers is systemically studied by electrostatic force microscopy in combination with non-linear Thomas-Fermi theory to interpret the experimental results. The ambipolar transport behavior of 1-40 layers of WSe 2 transistors is systematically investigated with varied temperature from 300 to 5 K. The thickness-dependent transport properties (carrier mobility and Schottky barrier) are discussed. Furthermore, the surface potential of WSe 2 as a function of gate voltage is performed under Kelvin probe force microscopy to directly investigate its ambipolar behavior. The results show that the Fermi level will upshift by 100 meV when WSe 2 transmits from an insulator to an n-type semiconductor and downshift by 340 meV when WSe 2 transmits from an insulator to a p-type semiconductor. Finally, the ambipolar WSe 2 transistor-based analog circuit exhibits phase-control by gate voltage in an analog inverter, which demonstrates practical application in 2D communication electronics.

show abstract

Section: Introductionmentioning

confidence: 99%

The ambipolar transport behavior of WSe2 transistors and its analogue circuits

et al. 2018

View full text Add to dashboard Cite

show abstract

“…As it is already known that the oxidation of BP readily occurs under air ambient to form PO X , we have rinsed the device to remove the oxide layer on the surface and performed an annealing process under vacuum condition to evaporate the remaining water molecules and improve contact property between BP and the metal electrodes or the substrate. [23][24][25] As a result, the surface of BP film is clean without bubbles caused by PO X ·H 2 O and the film is completely stuck to the patterned substrate without voids underneath as shown in Figure 1b. Figure 1c is Raman spectra of BP flake; BP-related peaks are indicated at ∼363, ∼440 and ∼466 cm −1 , which correspond to A g 1 , B 2g , and A g 2 phonon modes of BP, respectively.…”

Section: Resultsmentioning

confidence: 99%

Chemical Doping Effects of Gas Molecules on Black Phosphorus Field-Effect Transistors

Kim

Lee

Kim

2018

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Black phosphorus (BP) is a recently rediscovered layered material with outstanding optical and electrical properties. Its large adsorption energy and high surface-to-volume ratio have motivated chemical sensing and doping applications. We analyzed the charge transport properties as BP-based field-effect transistors (FETs) were chemically doped by adsorption of gas molecules. The electron-withdrawing NO 2 and the electron-donating NH 3 molecules were applied to observe p-doping and n-doping behaviors, respectively, in BP channel layer. Y-function method was used to extract the device parameters, allowing us to elucidate the chemical doping effects of different types of gas molecules in BP FETs. Excellent sensing ability of BP-based devices to gas molecules was also demonstrated. Our results provide a facile method to control the device properties of BP-based FET via the chemical doping. Two-dimensional (2D) materials have attracted a significant attention for their unique optical and electrical properties. The atomic layers are held to each other by van der Waals interaction and therefore can be easily exfoliated into high-quality nanoscale films. With their atomic thickness, 2D materials have inherent high surface-to-volume ratios that can be a great advantage in semiconductor optoelectronics requiring nanoscale devices with high performance.1,2 The higher the surface-to-volume ratio, the more active sites will be available for sensing in a fixed size device. Different 2D layered materials including graphene and transition metal dichalcogenides (TMDCs) were applied to chemical and gas sensors and showed excellent sensing properties. 3-5Black phosphorus (BP) has been highlighted as a promising 2D material with thickness-dependent direct bandgap and excellent electrical properties comparable to those of graphene or other layered materials. The outstanding performance as a transistor material was proved by its high carrier mobility and drain current modulation reaching 1,000 cm 2 /V·s and 10 5 , respectively. 6,7 Its distinctive sensitivity was also observed to be higher than other 2D materials as it has larger adsorption energy and puckered structure that leads to even higher surface-tovolume ratio and increased adsorption sites. 8,9 Thus, there have been various studies on high-performance BP-based chemical sensors; ultrasensitive and selective responses to NO 2 gas, water molecules or ions were reported.10-13 Abbas et al. reported on chemical sensing of NO 2 using BP-based field-effect transistors (FETs) and Cho et al. demonstrated superior chemical sensing performance of BP by comparing to those of molybdenum disulfide and graphene. 8,13 Cui et al. also studied ultrahigh sensitivity along with the thickness-dependent sensing properties of BP.14 Lee et al. fabricated suspended BP-based sensors to enhance the sensing performance. 15Although the high performance of BP-based chemical sensors has been demonstrated through previous reports, the chemical doping effects and the change in the device parameters caused by...

show abstract

“…The V oc and I sc comparisons between the three devices containing different layer number variations suggest potential photovoltaic engineering by tailoring the thicknesses and their difference of the flakes which can be realized through fabrication techniques such as etching. [49][50][51] Further comparison between the three devices is made in terms of their P el , EQE, and η with the results given in Figure 4c-e, respectively. In Figure 4c, we see that D1 produced the largest electrical power while it has the least appealing EQE performance as shown in Figure 4b.…”

Section: Photovoltaics In Bp Heterojunction Diodementioning

confidence: 99%

Pronounced Photovoltaic Effect in Electrically Tunable Lateral Black‐Phosphorus Heterojunction Diode

Wang

Huang

Tan

et al. 2017

Adv Elect Materials

View full text Add to dashboard Cite

complicated split-gates structure and suffer from nonabrupt junction interface due to the divergence of static electric field, limiting their practical applications. 2D lateral homojunctions can be achieved by selective chemical doping as well, as in few-layer MoS 2 [7] and BP cases. [17,18] In addition to homojunctions, heterojunctions have recently been under intense study to extend further the frontiers of 2D materials for electronic and optoelectronics. Particularly, by vertically stacking together flakes of different 2D materials, the so-called van der Waals heterojunction is formed which gathered extensive attention by offering a vast number of candidate structures for high-performance optoelectronic applications. [3,8,11,15,19,20] Nevertheless, the construction of this structure usually requires a dry/wet transfer technique that complicates the fabrication process. [21] Besides, it also tends to suffer from contaminants and bubbles introduced during the transfer, resulting in unwanted defects at the interface. [11] In contrast to vertical heterojunctions, lateral heterojunctions composed of p-and n-type TMDCs semiconductors are also explored where disparate materials can be grown along the edges of the previously grown flakes in the epitaxy process. [22][23][24] Yet, this strategy is severely challenged by the control of large-area uniform growth and the high yield of clean junction interface. As well known, an inherent nature of 2D materials is their thickness-(or layer-number-) dependent bandgaps. [25] Such dependence implies energy bands discontinuities at the interface of different-layer-number films, forming spontaneously a lateral heterojunction distinct from the conventional ones. [26][27][28][29] The study on this kind of structure is likely to expand the realms of 2D materials diverse applications but few works have been done. [26,28,29] Recently, few-layer black phosphorus has been rediscovered as a novel promising 2D semiconductor for nextgeneration nanoelectronic and optoelectronic devices due to its direct bandgap, ambipolar conduction, anisotropic nature, and a high field-effect hole mobility. [30][31][32][33] Especially, BP has a largely adjustable direct thickness-dependent bandgap ranging from 2.0 eV for monolayer to 0.3 eV for its bulk form, [34] which bridges the bandgap space between gapless graphene and large gap TMDCs by covering the mid-infrared to near-infrared wavelengths, leading to new electronic and optoelectronic devices. [33] In this work, we experimentally demonstrate a gate-tunable all-BP lateral heterojunction diode with thickness-induced bandgap difference for high-performance photovoltaic application, Recently, both lateral and vertical p-n junctions have been realized in 2D materials using various strategies, with a number of works on exploring the potential of lateral heterojunctions resulting from thickness-modulated bandgaps at the interface. Here, electrically tunable all-black-phosphorus (BP) lateral heterojunction diodes, without the need of split-gating or sele...

show abstract

Ultrathin and Flat Layer Black Phosphorus Fabricated by Reactive Oxygen and Water Rinse

Cited by 75 publications

References 56 publications

The ambipolar transport behavior of WSe2 transistors and its analogue circuits

The ambipolar transport behavior of WSe2 transistors and its analogue circuits

Chemical Doping Effects of Gas Molecules on Black Phosphorus Field-Effect Transistors

Pronounced Photovoltaic Effect in Electrically Tunable Lateral Black‐Phosphorus Heterojunction Diode

Contact Info

Product

Resources

About