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Landin, Lars
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Jain, V., Wallentin, J., Borgström, M., Storm, K., Landin, L., Wickert, P., . . . Pettersson, H. (2012). A comparative study of nanowire based infrared p+-i-n+ photodetectors. In: : . Paper presented at International Conference on the Physics of Semiconductors, Zürich, Switzerland, July 29th to August 3rd, 2012.
Öppna denna publikation i ny flik eller fönster >>A comparative study of nanowire based infrared p+-i-n+ photodetectors
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2012 (Engelska)Konferensbidrag, Poster (med eller utan abstract) (Refereegranskat)
Abstract [en]

We present a comparative study of electrical and optical properties of two types of p+-i-n+ photodetectors based on self-assembled ensembles of vertical InP nanowires (NWs) monolithically grown on InP. The detectors differ in the type of p+ contact, one detector geometry has p+-i-n+ segments integrated into the NWs (type A) while the other detector has i-n+ NW segments grown directly on a p+ substrate(type B). The samples were prepared by first depositing 80 nm Au nanoparticles on a p+ InP substrate using an aerosol technique and subsequently growing NWs using MOVPE. The NWs have a polytypecrystal structure of alternating wurtzite and zincblende segments. The processing of the detectors include deposition of SiO2, followed by an etching step to remove the oxide from the tip of the NWs, and finally sputtering of ITO on 1x1 mm2 device areas. The two most prominent differences between the detectors concern the current-voltage (I-V) characteristics and the spatial location of generated photocurrent. From spectrally resolved photocurrent measurements, we conclude that the photocurrent in detector type A is primarily generated in the NWs, whereas the photocurrent in type B detectors mainly stems from the substrate. Photogenerated carriers in the substrate diffuse to the NWs where they are effectively funnelled into the NWs. The I-V characteristics of the type A detector displays a non-trivial transport behaviour for forward biases, whereas type B shows excellent rectifying behavior with an ideality factor of about 2.5. We will discuss detailed analysis of the spectral fingerprints of the two detector types revealing the mixed crystal phase of the polytype NWs and bandstructure effects, temperature dependence of the I-V characteristics and typical photodetector parameters.

Nyckelord
Nanowire, Infrared Photodetectors
Nationell ämneskategori
Nanoteknik
Identifikatorer
urn:nbn:se:hh:diva-19670 (URN)
Konferens
International Conference on the Physics of Semiconductors, Zürich, Switzerland, July 29th to August 3rd, 2012
Projekt
More than Moore via III-V Nanowires
Forskningsfinansiär
Vetenskapsrådet
Tillgänglig från: 2012-10-04 Skapad: 2012-09-18 Senast uppdaterad: 2018-04-03Bibliografiskt granskad
Pettersson, H., Zubritskaya, I., Nghia, N. T., Wallentin, J., Borgström, M. T., Storm, K., . . . Samuelson, L. (2012). Electrical and optical properties of InP nanowire ensemble p(+)-i-n(+) photodetectors. Nanotechnology, 23(13), Article ID 135201.
Öppna denna publikation i ny flik eller fönster >>Electrical and optical properties of InP nanowire ensemble p(+)-i-n(+) photodetectors
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2012 (Engelska)Ingår i: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 23, nr 13, artikel-id 135201Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We report on a comprehensive study of electrical and optical properties of efficient near-infrared p(+)-i-n(+) photodetectors based on large ensembles of self-assembled, vertically aligned i-n(+) InP nanowires monolithically grown on a common p(+) InP substrate without any buffer layer. The nanowires have a polytype modulated crystal structure of wurtzite and zinc blende. The electrical data display excellent rectifying behavior with an ideality factor of about 2.5 at 300 K. The ideality factor scales with 1/T, which possibly reflects deviations from classical transport models due to the mixed crystal phase of the nanowires. The observed dark leakage current is of the order of merely similar to 100 fA/nanowire at 1 V reverse bias. The detectors display a linear increase of the photocurrent with reverse bias up to about 10 pA/nanowire at 5 V. From spectrally resolved measurements, we conclude that the photocurrent is primarily generated by funneling photogenerated carriers from the substrate into the NWs. Contributions from direct excitation of the NWs become increasingly important at low temperatures. The photocurrent decreases with temperature with an activation energy of about 50 meV, which we discuss in terms of a temperature-dependent diffusion length in the substrate and perturbed transport through the mixed-phase nanowires. © 2012 IOP Publishing Ltd.

Ort, förlag, år, upplaga, sidor
Bristol, UK: Institute of Physics Publishing (IOPP), 2012
Nationell ämneskategori
Den kondenserade materiens fysik
Identifikatorer
urn:nbn:se:hh:diva-18867 (URN)10.1088/0957-4484/23/13/135201 (DOI)000301663900001 ()2-s2.0-84858387129 (Scopus ID)
Forskningsfinansiär
Vetenskapsrådet
Anmärkning

Funding: Halmstad University, Erik Johan Ljungberg Foundation, Carl Trygger Foundation, Swedish Research Council, Swedish National Board for Industrial and Technological Development, Swedish Foundation for Strategic Research, EU (grant no. 214814) & E.ON AG as part of the E.ON International Research Initiative 

Tillgänglig från: 2012-06-27 Skapad: 2012-06-25 Senast uppdaterad: 2018-04-03Bibliografiskt granskad
Amin, M. N., Alam, M. O. O. & Landin, L. (2011). Electrical and optical characteristics of Infrared Photodetectors based on InP nanowire. Paper presented at 14th International Conference on Computer and Information Technology, ICCIT 2011, Dhaka, Bangladesh, 22-24 December, 2011. 14th International Conference on Computer and Information Technology, ICCIT 2011, 629-634, Article ID 6164864.
Öppna denna publikation i ny flik eller fönster >>Electrical and optical characteristics of Infrared Photodetectors based on InP nanowire
2011 (Engelska)Ingår i: 14th International Conference on Computer and Information Technology, ICCIT 2011, s. 629-634, artikel-id 6164864Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

High speed photodetectors are most sophisticated optoelectronic devices, because it has high photo sensitivity, and allow a large wavelength range of detection as a receiver from 750 nm to 1.3-1.55 μm in the optical communication system. Since the last decade, the electrical and optical characteristics of photodetectors have been investigated to improve their performance and price. We have worked on two different type of infrared photodetectors based on nanowire. One photodetector was p-n photodiode, and the other one was p-i-n structure. We investigated the detector performance at 77K-300K temperature corresponding with wavelength in darkness and under illumination as regarding breakdown voltage, sensitivity, and quantum efficiency. We have also compared the differences between the two photodetectors performance characteristics. © 2011 IEEE.

Ort, förlag, år, upplaga, sidor
Piscataway, NJ: IEEE, 2011
Nyckelord
Detector performance, High speed photodetectors, Infrared photodetector, InP, IR photodetectors, Large wavelength range, NWs, Optical characteristics, P-i-n structure, Performance characteristics, Information technology, Nanowires, Optical materials, Optoelectronic devices, Photodetectors
Nationell ämneskategori
Annan elektroteknik och elektronik
Identifikatorer
urn:nbn:se:hh:diva-37510 (URN)10.1109/ICCITechn.2011.6164864 (DOI)2-s2.0-84860015310 (Scopus ID)
Konferens
14th International Conference on Computer and Information Technology, ICCIT 2011, Dhaka, Bangladesh, 22-24 December, 2011
Tillgänglig från: 2018-07-09 Skapad: 2018-07-09 Senast uppdaterad: 2018-07-09Bibliografiskt granskad
Pettersson, H., Trägårdh, J., Persson, A. I., Landin, L., Hessman, D. & Samuelson, L. E. (2006). Infrared Photodetectors in Heterostructure Nanowires. Nano letters (Print), 6(2), 229-232
Öppna denna publikation i ny flik eller fönster >>Infrared Photodetectors in Heterostructure Nanowires
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2006 (Engelska)Ingår i: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 6, nr 2, s. 229-232Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

We report on spectrally resolved photocurrent measurements on single self-assembled nanowire heterostructures. The wires, typically 3 μm long with an average diameter of 85 nm, consist of InAs with a 1 μm central part of InAsP. Two different sets of wires were prepared with phosphorus contents of 15 ±3% and 35 ±3%, respectively, as determined by energy-dispersive spectroscopy measurements made in transmission electron microscopy. Ohmic contacts are fabricated to the InAs ends of the wire using e-beam lithography. The conduction band offset between the InAs and InAsP regions virtually removes the dark current through the wires at low temperature. In the optical experiments, interband excitation in the phosphorus-rich part of the wires results in a photocurrent with threshold energies of about 0.65 and 0.82 eV, respectively, in qualitative agreement with the expected band gap of the two compositions. Furthermore, a strong polarization dependence is observed with an order of magnitude larger photocurrent for light polarized parallel to the wire than for light polarized perpendicular to the wire. We believe that these wires form promising candidates as nanoscale infrared polarization-sensitive photodetectors.

Ort, förlag, år, upplaga, sidor
Washington: American Chemical Society (ACS), 2006
Nyckelord
Infrared Photodetectors, Nanowires
Nationell ämneskategori
Annan elektroteknik och elektronik
Identifikatorer
urn:nbn:se:hh:diva-205 (URN)10.1021/nl052170l (DOI)000235532700017 ()2-s2.0-33644914252 (Scopus ID)2082/490 (Lokalt ID)2082/490 (Arkivnummer)2082/490 (OAI)
Tillgänglig från: 2006-11-23 Skapad: 2006-11-23 Senast uppdaterad: 2018-04-03Bibliografiskt granskad
Pettersson, H., Landin, L., Fu, Y., Kleverman, M., Borgström, M., Seifert, W. & Samuelson, L. (2005). Photocurrent spectroscopy on self-assembled InAs quantum dots embedded in InP. Microelectronics Journal, 36(3-6), 227-230
Öppna denna publikation i ny flik eller fönster >>Photocurrent spectroscopy on self-assembled InAs quantum dots embedded in InP
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2005 (Engelska)Ingår i: Microelectronics Journal, ISSN 0026-2692, Vol. 36, nr 3-6, s. 227-230Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

In this work, we report on an overview of recent results from Fourier transform photocurrent (FTPC) measurements in the infrared spectral region on ensembles of self-assembled InAs quantum dots embedded in a matrix of InP. In interband PC, clear signals related to the dots are observed. Comparing the PC- and PL spectra, we observe that the fundamental transition is absent in the PC spectra, which we interpret in terms of Pauliblocking due to a filled electron ground state of the dots. Our results furthermore suggest that an Auger process is involved in forming the interband PC signal. In intersubband PC, peaks related to transitions from the dots' ground- and first excited states to the conduction band of the matrix are observed. Using a novel approach of combining FTPC with illumination from an additional external non-modulated light source, we have measured the spectral distribution of photoionization of excitons in quantum dots and found an exciton binding energy in good agreement with theoretical calculations.

Ort, förlag, år, upplaga, sidor
Amsterdam: Elsevier, 2005
Nyckelord
QDIP, Photocurrent spectroscopy, Exiton photoionization
Nationell ämneskategori
Teknik och teknologier
Identifikatorer
urn:nbn:se:hh:diva-206 (URN)10.1016/j.mejo.2005.02.011 (DOI)000229666000016 ()2-s2.0-33644542110 (Scopus ID)2082/491 (Lokalt ID)2082/491 (Arkivnummer)2082/491 (OAI)
Tillgänglig från: 2006-11-23 Skapad: 2006-11-23 Senast uppdaterad: 2018-04-03Bibliografiskt granskad
Trägårdh, J., Persson, A., Hessman, D., Pettersson, H., Landin, L. & Samuelson, L. (2005). Photocurrent Spectroscopy on Single Heterostructure Nanowires. In: Symposium EE: Progress in Semiconductor Materials V-Novel Materials and Electronic and Optoelectronic Applications. Paper presented at 2005 MRS Fall Meeting & Exhibit, 27 November – 2 December 2005, Boston, Massachusetts, US (pp. 753-753).
Öppna denna publikation i ny flik eller fönster >>Photocurrent Spectroscopy on Single Heterostructure Nanowires
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2005 (Engelska)Ingår i: Symposium EE: Progress in Semiconductor Materials V-Novel Materials and Electronic and Optoelectronic Applications, 2005, s. 753-753Konferensbidrag, Muntlig presentation med publicerat abstract (Refereegranskat)
Nationell ämneskategori
Naturvetenskap Den kondenserade materiens fysik
Identifikatorer
urn:nbn:se:hh:diva-22360 (URN)
Konferens
2005 MRS Fall Meeting & Exhibit, 27 November – 2 December 2005, Boston, Massachusetts, US
Tillgänglig från: 2013-05-28 Skapad: 2013-05-28 Senast uppdaterad: 2018-04-03Bibliografiskt granskad
Pettersson, H., Landin, L., Kleverman, M., Seifert, W., Samuelson, L., Fu, Y. & Willander, M. (2004). Intersubband photoconductivity of self-assembled InAs quantum dots embedded in InP. Journal of Applied Physics, 95(4), 1829-1831
Öppna denna publikation i ny flik eller fönster >>Intersubband photoconductivity of self-assembled InAs quantum dots embedded in InP
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2004 (Engelska)Ingår i: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 95, nr 4, s. 1829-1831Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The results from photoconductivity (PC) measurements on InAs dots embedded in InP are presented. The PC technique is recently applied to the study of InAs dots embedded in matrices of GaAs and Al0.3Ga0.7As matrix, respectively. It is demonstrated that this technique reveals important new physical insight into the electronic structure of the InAs/InP dots, information that cannot easily be obtained by other techniques.

Ort, förlag, år, upplaga, sidor
American Institute of Physics (AIP), 2004
Nyckelord
Conduction band, Electric conductivity, Free electron theory of metals, Quantum dots
Nationell ämneskategori
Teknik och teknologier
Identifikatorer
urn:nbn:se:hh:diva-203 (URN)10.1063/1.1638892 (DOI)000188654100033 ()2-s2.0-1542306860 (Scopus ID)2082/488 (Lokalt ID)2082/488 (Arkivnummer)2082/488 (OAI)
Tillgänglig från: 2006-11-23 Skapad: 2006-11-23 Senast uppdaterad: 2018-04-03Bibliografiskt granskad
Pettersson, H., Landin, L., Liu, R. S., Seifert, W., Pistol, M. E. & Samuelson, L. (2004). Photoexcitation of excitons in self-assembled quantum dots. Applied Physics Letters, 85(21), 5046-5048
Öppna denna publikation i ny flik eller fönster >>Photoexcitation of excitons in self-assembled quantum dots
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2004 (Engelska)Ingår i: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 85, nr 21, s. 5046-5048Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Using an approach of combining Fourier transform infrared spectroscopy with resonant illumination from a secondary external light source, we have measured the photocurrent (PC) for multiple layers of self-assembled InAs dots embedded in a matrix of InP. Without external illumination, we observe photoexcitation of electrons from bound states in the dots to the InP barrier. By additional illumination from the external light source, a strong broadening of the PC signal is observed. We interpret this broadening in terms of photoexcitation of electrons in the presence of additional holes in the dots created by the external light source. We extract the spectral distribution of the photoexcitation process at 6 and 77 K, respectively, and show by comparison with theoretical calculations that it is consistent with an exciton binding energy of 20 meV.

Ort, förlag, år, upplaga, sidor
American Institute of Physics (AIP), 2004
Nyckelord
Electronics, Fourier transformations, Infrared spectroscopy, Microelectronics, Lolecular electronics, Quantum electronics, Quantum dots
Nationell ämneskategori
Teknik och teknologier
Identifikatorer
urn:nbn:se:hh:diva-207 (URN)10.1063/1.1824174 (DOI)000225300600073 ()2-s2.0-19144366094 (Scopus ID)2082/492 (Lokalt ID)2082/492 (Arkivnummer)2082/492 (OAI)
Tillgänglig från: 2006-11-23 Skapad: 2006-11-23 Senast uppdaterad: 2018-04-03Bibliografiskt granskad
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