Wavelength dependence of the photo-electromotive-force effect in CdTe:V crystal with bipolar photoconductivity

We report on detailed investigation of the photo-electromotive-force (photo-EMF) effect in semiconductor with bipolar photoconductivity of impurity type in a spectral region close to the fundamental absorption edge, where both the photoconductivity and the photo- EMF response reach their maxima. The...

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Detalles Bibliográficos
Autores: SERGUEI STEPANOV, PONCIANO RODRIGUEZ MONTERO, SVETLANA MANSUROVA SERGUEYEVNA
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:México
Institución:Instituto Nacional de Astrofísica, Óptica y Electrónica
Repositorio:Repositorio Institucional del INAOE
Idioma:inglés
OAI Identifier:oai:inaoe.repositorioinstitucional.mx:1009/928
Acceso en línea:http://inaoe.repositorioinstitucional.mx/jspui/handle/1009/928
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/cti/1
info:eu-repo/classification/cti/22
info:eu-repo/classification/cti/2209
Descripción
Sumario:We report on detailed investigation of the photo-electromotive-force (photo-EMF) effect in semiconductor with bipolar photoconductivity of impurity type in a spectral region close to the fundamental absorption edge, where both the photoconductivity and the photo- EMF response reach their maxima. The experiments performed with CdTe:V crystal (ΔE ≈ 1.51 eV) in the spectral range of 826–853 nm show that dynamics of the photo-EMF signal formation in this crystal is governed by relaxation of slow majority photocarriers–holes with the life-time which goes down from ƭ ≈ 9 ls at 850 nm to ≈ 6.5 ls at 826 nm. The minority photocarriers (electrons), which contribute approximately 10% of the total photoconductivity, also demonstrate significant wavelength dependence of their diffusion length with LD ≈ 8.5 lm at 850 nm and ≈ 6.3 lm at 830 nm. The reported results show significant improvement in responsivity of the bipolar CdTe:V photo-EMF detector when it is operated at λ = 840 nm (by factor ≈ 2.5 as compared with that at 852 nm).