Varistor-like current-voltage characteristic of porous silicon

The porous silicon (PS) current-voltage characteristic (CVC) has measured in transverse and longitudinal applied electric field. The obtained CVC has a varistor-like shape. Besides the practical application this confirms the PS grain structure whose influence is discussed in analizing the mechanism...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Datum:1999
Hauptverfasser: Vakulenko, O.V., Kondratenko, S.V., Shutov, B.M.
Format: Artikel
Sprache:English
Veröffentlicht: Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України 1999
Schriftenreihe:Semiconductor Physics Quantum Electronics & Optoelectronics
Online Zugang:http://dspace.nbuv.gov.ua/handle/123456789/119066
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Назва журналу:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Zitieren:Varistor-like current-voltage characteristic of porous silicon / O.V. Vakulenko, S.V. Kondratenko, B.M. Shutov // Semiconductor Physics Quantum Electronics & Optoelectronics. — 1999. — Т. 2, № 2. — С. 88-89. — Бібліогр.: 7 назв. — англ.

Institution

Digital Library of Periodicals of National Academy of Sciences of Ukraine
id irk-123456789-119066
record_format dspace
spelling irk-123456789-1190662017-06-04T03:03:44Z Varistor-like current-voltage characteristic of porous silicon Vakulenko, O.V. Kondratenko, S.V. Shutov, B.M. The porous silicon (PS) current-voltage characteristic (CVC) has measured in transverse and longitudinal applied electric field. The obtained CVC has a varistor-like shape. Besides the practical application this confirms the PS grain structure whose influence is discussed in analizing the mechanism of the visible luminescence in PS. 1999 Article Varistor-like current-voltage characteristic of porous silicon / O.V. Vakulenko, S.V. Kondratenko, B.M. Shutov // Semiconductor Physics Quantum Electronics & Optoelectronics. — 1999. — Т. 2, № 2. — С. 88-89. — Бібліогр.: 7 назв. — англ. 1560-8034 PACS 72.80.Ng, s5.11 http://dspace.nbuv.gov.ua/handle/123456789/119066 en Semiconductor Physics Quantum Electronics & Optoelectronics Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
language English
description The porous silicon (PS) current-voltage characteristic (CVC) has measured in transverse and longitudinal applied electric field. The obtained CVC has a varistor-like shape. Besides the practical application this confirms the PS grain structure whose influence is discussed in analizing the mechanism of the visible luminescence in PS.
format Article
author Vakulenko, O.V.
Kondratenko, S.V.
Shutov, B.M.
spellingShingle Vakulenko, O.V.
Kondratenko, S.V.
Shutov, B.M.
Varistor-like current-voltage characteristic of porous silicon
Semiconductor Physics Quantum Electronics & Optoelectronics
author_facet Vakulenko, O.V.
Kondratenko, S.V.
Shutov, B.M.
author_sort Vakulenko, O.V.
title Varistor-like current-voltage characteristic of porous silicon
title_short Varistor-like current-voltage characteristic of porous silicon
title_full Varistor-like current-voltage characteristic of porous silicon
title_fullStr Varistor-like current-voltage characteristic of porous silicon
title_full_unstemmed Varistor-like current-voltage characteristic of porous silicon
title_sort varistor-like current-voltage characteristic of porous silicon
publisher Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України
publishDate 1999
url http://dspace.nbuv.gov.ua/handle/123456789/119066
citation_txt Varistor-like current-voltage characteristic of porous silicon / O.V. Vakulenko, S.V. Kondratenko, B.M. Shutov // Semiconductor Physics Quantum Electronics & Optoelectronics. — 1999. — Т. 2, № 2. — С. 88-89. — Бібліогр.: 7 назв. — англ.
series Semiconductor Physics Quantum Electronics & Optoelectronics
work_keys_str_mv AT vakulenkoov varistorlikecurrentvoltagecharacteristicofporoussilicon
AT kondratenkosv varistorlikecurrentvoltagecharacteristicofporoussilicon
AT shutovbm varistorlikecurrentvoltagecharacteristicofporoussilicon
first_indexed 2025-07-08T15:10:19Z
last_indexed 2025-07-08T15:10:19Z
_version_ 1837091961335447552
fulltext 88 © 1999, Institute of Semiconductor Physics, National Academy of Sciences of Ukraine Semiconductor Physics, Quantum Electronics & Optoelectronics. 1999. V. 2, N 2. P. 88-89. 1. Introduction The notion of the nanocrystallites in randomly positioned quantum wires or quantum walls between neighbouring pores of the porous silicon (PS) samples has been applied by the reseachers to explain a lot of photophysical effects, the vis- ible photoluminescence in particular [1-3]. The availability of such grain structure may also manifest itself in the PS electrical properties. Hopefully, an asymmetric varistor-like current-voltage characteristic (CVC) can be observed in the structures with porous silicon layer. However, only asym- metric diode-like CVC has been reported [4-7]. So, the ques- tion about the existence of such grain structure could be sup- plementary verified if one succeeded in finding varistor-like CVC in the porous silicon samples. This has been the sub- ject of our work. The problem of measuring CVC of PS in longitudinal electric field, when both contacts are applied to the PS side, lies in the fact that only PS layer has a larger resistance in comparision with Si substrate. Consequently, one should expect a short out effect by the material of Si substrate. However, we succeeded in preparing the PS lay- ers without the short out effect. These layers in the multilayer structure of the PS, as all the others, consisted of Si nanocrys- tallites in SiOx (0 < x < 2) matrix, but differed from others by moderate oxidation. It is this moderate oxidation that favoured the conductivity enhancement of the relevant sublayer of the sample, as it has been reported [2,3]. Therefore, the partially oxidated layers in PS have been investigated. In addition, these layers showed a high-intensity visible photoluminescence. PACS 72.80.Ng, s5.11 Varistor-like current-voltage characteristic of porous silicon O.V. Vakulenko, S.V. Kondratenko, B.M. Shutov . Taras Shevchenko Kyiv Univ., 6 Glushkova Prosp., 252127 Kyiv, Ukraine Tel. 8 044 266 01 62, E-mail: kondr@hq.ups.kiev.ua Abstract. The porous silicon (PS) current-voltage characteristic (CVC) has measured in transverse and longitudinal applied electric field. The obtained CVC has a varistor-like shape. Besides the practical application this confirms the PS grain structure whose influence is discussed in analizing the mechanism of the visible luminescence in PS. Keywords: varistor, current-voltage characteristic, porous silicon. Paper received 25.06.99; revised manuscript received 06.07.99; accepted for publication 12.07.99. 2. Experiment The porous silicon samples were prepared using anodiza- tion in 48% HF solution with a current density 25 mA/cm2 for ten minutes. (111) - oriented p-type silicon wafers were used for substrates. Before anodization the substrates were cleaned, and the ohmic contact was formed in a thin Al lay- er on the back side of the Si substrate. The PS layer thick- ness was approximately 5 µm. After anodizing a few semi- transparant Au point contacts have been deposited onto the PS surface (Fig.1). This made it possible to observe con- point contact P S S i substrate A l conta ct Fig. 1. Structure with PS layer for CVC measurements. s O.V. Vakulenko et al.: Varistor-like current-voltage characteristic of porous silicon 89SQO, 2(2), 1999 ductivity in transverse and longitudinal applied electric field in relation to the PS layer. 3. Results and discussion Asymmetric diode-like current-voltage characteristic is al- ways observed in transverse electric field measurments, be- cause the porous silicon layer and the Si substrate give rise to a rectifying contact. According to the transverse field measurments, our sam- ples have been divided into two groups. For the first one, the current-voltage characteristic is similar to that for two oppositely switched diodes. This testifies that metal - PS contact forms a potential wall. The other group of the sam- ples exhibited a symmetric varistor-like CVC (Fig.2). The CVC of these samples can be described by the equation: I = B⋅Un, where B is the sample constant depending on a lot of factors: preparation and storage conditions and many oth- ers. Here n is the varistor nonlinearity coefficient. For the majority of PS samples it varies from 4 to 5. The CVC of the sample showed in Fig.2 exhibits the magnitude of n ≈ 4.2. The varistor-like CVC points to the fact that potential wall on the PS - Au contact interface is absent for this type of samples. The PS material nonlinearity is usually attribut- ed to the varistor conductivity enhancement in increasing the electric field intensity. In our case, it may be explained by the following reasons: emission of electrons from grain edges of the nanocrystallite structure formed in PS; large-field conduc- tivity enhacement of the oxide film which covers the pores; microheating of the contacting points between pores, etc. The PS material irregularity does not make it possible to choose one of the suggested reasons. However, the fact of ex- istence of varistor-like CVC, besides the practical application, is of interest, because it favours the grain, nanocrystallite PS structure, whose influence is usually discussed in analyzing the mechanisms of the visible photoluminescence in PS. References 1. S.V. Svechnikov, A.V. Sachenko, G.A. Sukach, A.M. Yevstigneyev, E.B. Kaganovich. Optoelektronika i poluprovodnikovaya tekhnika, 27, p. 3-29 (1994) (in Russian). 2. V.G. Golubev, A.V. Zherzdnev, G.K. Moroz, A.V. Patsekin, D.T. Yan. Fizika i tekhnika poluprovodnikov, 30(5), p. 852-863 (1996) (in Russian). 3. Y.Kanemitsu. Phys. Rev.B. 48(7),p. 4883-4886 (1993) 4. T.Ozaki, M.Araki, S.Yoshimura, H.Koyama, N.Koshida. J. Appl. Phys. 76(3), p.1986-1988 (1994). 5. L.V. Beliakov, D.N. Goriachev, O.M. Sreseli, I.D. Yaroshetski. Fizika i tekhnika poluprovodnikov, 27(8), p.1371-1375 (1993) (in Russian). 6. F.Namavar, H.P.Maruska, N.M.Khoran. Appl. Phys. Lett. 60(20), p.2514-2516 (1992). 7. N.Koshida, M.Koyama, Appl. Phys. Lett. 60(3), p.347-349 (1992). -20 -15 -10 -5 0 5 10 15 20 U, V I , Am800 600 400 200 -200 -400 -600 -800 Fig. 2. Varistor-like CVC of the PS samples observed in longitudinally applied electric field.