Hydrogenated silicon (Si:H) layers and Si:H/p-Si heterostructures were produced by multiple-energy (3-24 keV) high-dose (5 x 10(16)-3 x 10(17) cm(-2)) hydrogen implantation into p-Si wafers. After implantation, current transport across the structures is controlled by the Poole-Frenkel mechanism, with the energy of the dominating emission center equal to E-c -0.89 eV. The maximum photosensitivity is observed for structures implanted with 3.2 x 10(17) cm(-2) of hydrogen and annealed in the temperature range of 250-300degreesC. The band gap of the Si:H layer E-g approximate to 2.4 eV, and the dielectric constant epsilon approximate to 3.2. The density of states near the Fermi level is (1-2) x 10(17) cm(-3) eV(-1). (C) 2003 MAIK "Nauka/Interperiodica".
机构:
Natl Res Ctr, Solid State Elect Lab, Solid State Phys Dept, Phys Res Div, 33 El Bohouth St, Giza 12622, EgyptNatl Res Ctr, Solid State Elect Lab, Solid State Phys Dept, Phys Res Div, 33 El Bohouth St, Giza 12622, Egypt