Colloidal sol-gel ITO films on tube grown silicon

Electrical and optical properties of colloidal PTO sol-gel films on glass s ubstrates have been investigated. The optical gap of 3.14 eV and room tempe rature conductivity of 4 Ohm(-1) cm(-1) were obtained on ITO layers of abou t 500 Angstrom thickness. Heterostructures of ITO/n-Si have been obtained b y colloidal sol-gel deposition of ITO. In this deposition method, the oxida tion of silicon during the heterostructure formation can be avoided. The si licon substrates were cut out of silicon tubes. Electrical and photoelectri c properties of these structures have been studied in comparison with those of p-n tube-Si junctions obtained by thermal boron diffusion. On ITO/n-Si heterojunctions, the spectral quantum efficiency has a maximum value of abo ut two times higher and a blue shift of the maximum position from 0.75 to 0 .6 mu m, than those for p-n junctions. A theoretical investigation of the I -V curves for ITO/n-Si heterojunctions under various illumination levels ha s been performed and contribution of the tunneling and series resistance ph enomena were evaluated. (C) 1999 Elsevier Science S.A. All rights reserved.