Current-voltage characteristics of Schottky barrier structures on porous silicon, and effect of an organic stabilizer film

The stability and reproducibility of current-voltage curves of Schottky bar rier structures on particular porous silicon surfaces used for obtaining el ectroluminescence is greatly improved by first coating the surface with a c onducting polymer, poly-4-dicyanomethylene-4H-cyclopenta [2,1-b:3,4-b'] dit hiophene. With such coated structures it is possible to fit the usual diode formula at room temperatures with a quality factor of 3.0, obviating the n eed for more complex theories. The stability of electroluminescence, which shows a redshift from 500 to 580 nm after coating, is also greatly improved . The coating appears to chemically react with the hydride surface and also mechanically strengthens the structure. (C) 2000 American Institute of Phy sics. [S0021-8979(00)02113-7].