Composition Dependence of Photoconductivity in Amorphous Thin Films of Se.80-xTe.20Gex

D. KUMAR; S. KUMAR

Makale detayları

Composition Dependence of Photoconductivity in Amorphous Thin Films of Se.80-xTe.20Gex

Yazarlar:

D. KUMAR | S. KUMAR

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Physics 2005 Vol.29 Issue 2, pp.91-96

Belge Tipi:

Makale

Yayın Tarihi:

1/2005

Belge Dili:

Türkçe

Document ID (Org No.):

2000761574

Sıklık:

İki Aylık

eISSN:

1303-6122

pISSN:

1300-0101

Anahtar kelimeler:

Özet:

 

The present paper reports the dependence on composition of  photoconductivity in vacuum evaporated thin films of amorphous  Se.80-xTe.20Gex (x = .05, .10, .15 and .20).  Temperature  dependence of conductivity in dark as well as in presence of light  show that conduction is through a thermally activated process in both  cases.  The activation energy is found to decrease with increase in  light intensity, indicating shift of the Fermi level with intensity.   A correlation between activation energy and the pre-exponential factor  is observed in all the compositions, which could be fitted to the  Meyer-Neldel rule.  Measurements on the dependence of photoconductivity on intensity show  that photoconductivity increases with intensity as a power law, where  the power is found to be between 0.5 and 1.0.  The photosensitivity  sph/sd increases with Ge concentration.  This is  explained in terms of the decrease in the density of defect states  with increase of Ge content in a-Se.80-xTe.20Gex.  This is  consistent with the conclusions reported in the literature by  dielectric loss measurements.

 

The present paper reports the dependence on composition of  photoconductivity in vacuum evaporated thin films of amorphous  Se.80-xTe.20Gex (x = .05, .10, .15 and .20).  Temperature  dependence of conductivity in dark as well as in presence of light  show that conduction is through a thermally activated process in both  cases.  The activation energy is found to decrease with increase in  light intensity, indicating shift of the Fermi level with intensity.   A correlation between activation energy and the pre-exponential factor  is observed in all the compositions, which could be fitted to the  Meyer-Neldel rule.  Measurements on the dependence of photoconductivity on intensity show  that photoconductivity increases with intensity as a power law, where  the power is found to be between 0.5 and 1.0.  The photosensitivity  sph/sd increases with Ge concentration.  This is  explained in terms of the decrease in the density of defect states  with increase of Ge content in a-Se.80-xTe.20Gex.  This is  consistent with the conclusions reported in the literature by  dielectric loss measurements.

Makale detayları

Composition Dependence of Photoconductivity in Amorphous Thin Films of Se.80-xTe.20Gex

Yazarlar:

D. KUMAR | S. KUMAR

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Physics 2005 Vol.29 Issue 2, pp.91-96

Belge Tipi:

Makale

Yayın Tarihi:

1/2005

Belge Dili:

Türkçe

Document ID (Org No.):

2000761574

Sıklık:

İki Aylık

eISSN:

1303-6122

pISSN:

1300-0101

Chalcogenide Glasses

Photoconductivity

Amorphous Thin films.

Sayı

Makale detayları

Composition Dependence of Photoconductivity in Amorphous Thin Films of Se.80-xTe.20Gex

Yazarlar: D. KUMAR | S. KUMAR

Yayıncı: TUBITAK

Dergi: Turkish Journal of Physics 2005 Vol.29 Issue 2, pp.91-96

Belge Tipi: Makale

Yayın Tarihi: 1/2005

Belge Dili: Türkçe

Document ID (Org No.): 2000761574

Sıklık: İki Aylık

eISSN: 1303-6122

pISSN: 1300-0101

Chalcogenide Glasses

Photoconductivity

Amorphous Thin films.

Sayı

Yazarlar:

D. KUMAR | S. KUMAR

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Physics 2005 Vol.29 Issue 2, pp.91-96

Belge Tipi:

Makale

Yayın Tarihi:

1/2005

Belge Dili:

Türkçe

Document ID (Org No.):

2000761574

Sıklık:

İki Aylık

eISSN:

1303-6122

pISSN:

1300-0101