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Amorphous thin films of chalcogenide glasses are well known as high photosensitive materials with a wide application in photonics, optoelectronics and information storage systems. In the present paper the experimental results on optical absorption and steady-state photocurrent of amorphous single amorphous layer structures Al-Ge0.30As0.04S0.66-Al (L1) AlGe0.09As0.09Se0.82-Al (L2), Al-As0.40S0.30Se0.30-Al (L3) as well as for amorphous heterostructure AlAs0.40S0.30Se0.30/Ge0.09As0.09Se0.82/Ge0.30As0.04S0.66-Al (HS) at different values of the applied voltage at positive and negative polarity of the illuminated top Al electrode are presented and discussed. The thickness of the component layers is also different with the ratio of the thickness about L1/L2/L3 = 1000/500/200 nm. The investigated multilayer structures contain the first material with the trigonal (As0.40S0.30Se0.30), and the other two layers contain trigonal as well as tetrahedral structural units (Ge0.09As0.09Se0.82, Ge0.30As0.04S0.66). The complex structure of the photocurrent spectra is governed to the different value of the optical band gap of the involved amorphous layer (about Eg~2.0 eV for the As0.40S0.30Se0.30 and Ge0.09As0.09Se0.82, and about Eg~3.0 eV for the Ge0.30As0.04S0.66). The obtained experimental results are discussed taking into account the depth of the light absorption depending of the nature and the thickness of each amorphous material, wavelength and the contact phenomena between the interfaces of the different material as well as between the interfaces metal-amorphous semiconductor with different work functions, as was demonstrated for the other amorphous thin film structures.
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