Your browser doesn't support javascript.
loading
Electrical and optical properties of InP nanowire ensemble p⁺-i-n⁺ photodetectors.
Pettersson, Håkan; Zubritskaya, Irina; Nghia, Ngo Tuan; Wallentin, Jesper; Borgström, Magnus T; Storm, Kristian; Landin, Lars; Wickert, Peter; Capasso, Federico; Samuelson, Lars.
Afiliação
  • Pettersson H; Laboratory of Mathematics, Physics and Electrical Engineering, Halmstad University, Box 823, SE-30118 Halmstad, Sweden. hakan.pettersson@hh.se
Nanotechnology ; 23(13): 135201, 2012 Apr 06.
Article em En | MEDLINE | ID: mdl-22418741
ABSTRACT
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 ∼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.

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Tipo de estudo: Prognostic_studies Idioma: En Revista: Nanotechnology Ano de publicação: 2012 Tipo de documento: Article País de afiliação: Suécia

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Tipo de estudo: Prognostic_studies Idioma: En Revista: Nanotechnology Ano de publicação: 2012 Tipo de documento: Article País de afiliação: Suécia