ABSTRACT
For its multifarious applications, porous silicon (PSi) is getting popular attention from the scientific and technological arena (Canham 1997; Pavesi and Dubos 1997; Tsamis et al. 2002). As it was testified before, the main attractions behind the research and development of porous silicon are very large surface to volume ratio of PSi, tailormade technology to control the surface morphology by varying the formation parameters, and relatively easy formation. However, most the important factor for its large-scale applications is the compatibility to silicon IC technology leading to the development of effective devices for electrical and microelectronics applications, photonics, sensors, optoelectronic system, and so on. Another technological advantage of PSi is the tailormade morphology for the desired applications. Recently, the eminent researchers working with PSi proposed the field to be an educational vehicle for introducing nanotechnology and interdisciplinary material science. However, for developing PSi-based devices and their integration to the electronic circuits, the most important requirement is the presence of low resistance and stable electrical contacts. As it is known, one of the main outstanding problems of PSi is the instability of its native interface due to the metastable Si-Hx termination (Tsai et al. 1991) that causes spontaneous oxidation in the ambient atmosphere and results in the degradation of surface structures. As a result, a stable ohmic contact formation (Deresmes et al. 1995; Stievenard and Deresmes 1995) becomes difficult and makes the commercial applications problematic. Therefore, the stabilization of the PSi surfaces and fabrication of reliable electrical contacts to PSi are the primary needs of the PSi-based devices.
