Imaging the formation of a p-n junction in a suspended carbon nanotube with scanning photocurrent microscopy

Buchs, Gilles; Barkelid, Maria; Bagiante, S.; Steele, Gary A.; Zwiller, Val

doi:10.1063/1.3645022

Cited by 16 publications

(19 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This linearly increasing current can be described by replacing the p-type Schottky diode of the equivalent circuit of Figure 2a with a series resistor. 29 Our quantitative model of the nanoscale diode device shows how a variety of device characteristics can arise from apparently similar devices. The work function of the metal contacts, the band gap of the CNT, and the transmission coefficients all strongly affect the device characteristics.…”

Section: Resultsmentioning

confidence: 98%

See 1 more Smart Citation

A nanoscale pn junction in series with tunable Schottky barriers

Aspitarte

McCulley

Minot

2017

Journal of Applied Physics

View full text Add to dashboard Cite

PN junctions in nanoscale materials are of interest for a range of technologies including photodetectors, solar cells and light-emitting diodes. However, Schottky barriers at the interface between metal contacts and the nanomaterial are often unavoidable. The effect of metalsemiconductor interfaces on the behavior of nanoscale diodes must be understood, both to extract the characteristics of the pn junction, and to understand the overall characteristics of the final device. Here, we study the current-voltage characteristics of diodes that are formed in fullysuspended carbon nanotubes. We utilize tunable Schottky barrier heights at the CNT-metal interface to elucidate the role of the Schottky barriers on the device characteristics. We develop a quantitative model to show how a variety of device characteristics can arise from apparently similar devices. Using our model we extract key parameters of the Schottky barriers and the pn junction, and predict the overall I-V characteristics of the device. Our equivalent circuit model is relevant to a variety of nanomaterial-based diode devices that are currently under investigation.

show abstract

Section: Resultsmentioning

confidence: 98%

“…Figure 1d shows the measured G(V g ) of a dual-gated suspended CNT. The CNT chiral index is (29,10) which corresponds to a diameter of 2.74 nm and an S 11 optical resonance energy of 430 meV (see Figure S2). To perform field-effect transistor measurements, the gates are configured such that V g1 = V g2 .…”

Section: Resultsmentioning

confidence: 99%

A nanoscale pn junction in series with tunable Schottky barriers

Aspitarte

McCulley

Minot

2017

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…Details about the device fabrication has been reported elsewhere. 13,14 Two local gates at the bottom of the trench are used for electrostatic doping. A schematic representation of the device geometry can be found in the inset in Fig.…”

Section: Methodsmentioning

confidence: 99%

“…The p-n junction was spatially located using scanning photocurrent microscopy, 13,15,16 where the excitation laser is raster scanned over the device and the photocurrent measured at every laser location. This generates the photocurrent image in Fig.…”

Section: Methodsmentioning

confidence: 99%

Single carbon nanotube photovoltaic device

Barkelid

Zwiller

2013

Journal of Applied Physics

View full text Add to dashboard Cite

Here we present photocurrent measurements on a single suspended carbon nanotube p-n junction. The p-n junction was induced by electrostatic doping by local gates, and the E11 and E22 resonances in the nanotube could be probed using photocurrent spectroscopy. Current-voltage characteristics were recorded, revealing an enhanced optoelectronic response on resonance. The internal power conversion efficiency for the nanotube diode was extracted on and off resonance with the E11 and E22, and a large internal power conversion efficiency was observed. An internal efficiency of up to 23% is reported for the E11, showing the potential of carbon nanotubes to be used as the active element in photovoltaic devices. Finally, a photovoltaic device is proposed which exploits this enhanced efficiency. V C 2013 AIP Publishing LLC.

show abstract

“…Although the resolution of a classical optical microscope is restricted by diffraction to about half of the optical wavelength, scanning near-field optical microscopy (SNOM) has been proved to be a simple and direct measurement technique capable of highenergy accuracy (better than 3 meV) and lateral resolution to characterize semiconductor/metal interfaces [7][8][9][10][11][12][13][14][15][16]. For example, Coluzza [7] et al studied the Pt/n-GaP buried Schottky junction by this spatially resolved technique and correlated the chemical inhomogeneities of the interface with the spatial variations of the diode transport properties.…”

Section: Introductionmentioning

confidence: 99%

Photocurrent imaging of CdS/Al interfaces based on microscopic analysis

et al. 2013

View full text Add to dashboard Cite

We investigate the lateral variations of photocurrent on CdS/Al interfaces, with a combination of a semiconductor characterization system and scanning near-field optical microscopy, in which the near-field probe is used to locally induce photocurrent on the CdS/Al interfaces with high spatial resolution. By analyzing the spatially resolved photoresponse, we find that the resolution is worsened in the photocurrent images by the lateral diffusion of the photoexcited electrons and that the photoelectric properties of the CdS/Al interfaces are strongly affected by the bias voltage. Furthermore, in a complementary experiment, we also demonstrate that the photocurrent measurements can reveal structures that are not present in the case of shear-force data. The analysis demonstrates the band structure and microscopic mechanism of CdS/Al heterostructures, which provide an effective approach for developing CdS-based photoelectronic devices.

show abstract

Imaging the formation of a p-n junction in a suspended carbon nanotube with scanning photocurrent microscopy

Cited by 16 publications

References 17 publications

A nanoscale pn junction in series with tunable Schottky barriers

A nanoscale pn junction in series with tunable Schottky barriers

Single carbon nanotube photovoltaic device

Photocurrent imaging of CdS/Al interfaces based on microscopic analysis

Contact Info

Product

Resources

About