Electroless Nickel Plating on Silicon

In the study of electroless Ni plating of Si wafers with p‐n junctions using conventional solutions, a pronounced difference in plating rate between p‐ and n‐type surfaces is observed. Further experiments show that rate difference probably should not only be attributed to the photovoltaic effect generated at the p‐n junctions but also to the electronegativity difference between p‐ and n‐type Si. The latter effect can be changed by addition of such material as or to the plating solution. Whereas addition increases the rate difference, EDTA addition decreases it. This fact which can be put to practical use gives an extra support for the explanation given above.