Silicon Nanowire Arrays for Ultrasensitive Label-Free Detection of DNA

Arrays of highly ordered silicon nanowires (SiNWs) are fabricated using complementary metal-oxide semiconductor (CMOS) compatible technology and their applications in biosensors are investigated. The SiNW arrays show a concentration-dependent resistance change upon hybridization to complementary target DNA. As in the case of other SiNW biosensing devices, the sensing mechanism can be understood in terms of the change in charge density at the SiNW surface after hybridization, the so called "field effect". The SiNW arrays discriminate satisfactorily against mismatched target DNA.