Current transport through mesa structures formed by Pt electroless deposition on p-Si wafers has been studied. The silicon treatment in the solution of sodium chloroplatinate in dilute HF acid is shown to result in both Pt nucleation on the Si surface ͑cathodic process͒ and Si wafer etching by fluoride ions ͑anodic process͒. These processes occurred simultaneously, forming the developed Pt/Si interface. Auger electron spectroscopy and C-V curves reveal the formation of a dielectric interface layer between Pt and Si of hundreds of nanometers that extends with the time of treatment. The electrical properties of mesa structures exhibit Schottky barrier behavior. Both conditions of current transport along the deposited layer and parameters of Schottky contact are defined vs. the deposition time and compared with that for thermally deposited Pt contact.The method of electroless deposition is known to provide a continuous metal coating on a semiconductor substrate by simple immersion in an appropriate aqueous solution and may have applications in microelectronics, namely, as the ultralarge scale integrated ͑ULSI͒ metallization, 1 as thin metal etch masks for deep UV lithography, 2 as ohmic contacts on GaAs, 3 etc. The main advantages of electroless deposition are the deposition selectivity, high metal purity, low operating temperature, planar topography, good working characteristics, low cost, and applicability for mass production. 4,5 Recently, methods of electroless deposition of various metals on an Si slab using the aqueous solutions of HF and metal salt have been elaborated. 6-8 The fluoride acid is the necessary component of the majority etchants applied for electroless or electrochemical silicon treatment. HF is also used widely in order to remove the native silicon oxide from the Si surface and to form the porous silicon layers. 9 The integration of the metal deposition process with silicon etching allows the creation of metal-semiconductor structures which may find practical implementation in chemical sensors. 10 The chemical interaction results in a metal penetration into an Si slab to a depth of up to few micrometers and results in alterations of the electrical properties of surface layer. 6-8 Though the structural features of such surfaces have already been studied there is a lack of data concerning the electrical behavior.In this work we consider the electrical properties of Si structures produced by treatment of Si with HF aqueous solutions of a platinum salt. The choice of Pt metallization is based on its high stability and good adhesion to Si. Figure 1 shows the design of the studied mesa patterns. The boron-doped (N p ϭ 2-3 • 10 15 cm Ϫ3 ) silicon slabs with ͑100͒ crystalline orientation, 300 m thick, were used as substrates. The native silicon oxide was removed in aqueous solution HF:H 2 O ϭ 1:4 before metal deposition. Then the silicon surfaces were treated by platinum deposition performed by immersing Si in a solution prepared by dissolving sodium chloroplatinate in dilute HF. The plating solution w...

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