Studies on the rectifying effect of the heterojunction between porous silicon and water-soluble copolymer of polyaniline

Rectifying diodes of the heterojunction between porous silicon (PS) and water-soluble copolymer of polyaniline (PAOABSA) with the rectifying ratio of 5.0 × 104 at ±3 V bias were fabricated and the rectifying characteristics of the heterojunction diode, Al/PS-PAOABSA/Au cell, were measured as a function of the sulfonated degree and thickness of the PAOABSA copolymer films, as well as the oxidation of silicon exposed to air. It was found that decreasing the sulfonated degree and thickness of the PAOABSA copolymer films is favorable for enhancement of rectifying characteristics of the heterojunction diodes. Moreover, it was noted that the oxidation of silicon exposed to air is harmful for the rectifying effect of the heterojunction diodes.