Study of the Electroless Deposition of Ni for Betavoltaic Battery Using PN Junction without Seed Layer

Abstract

The method and conditions of Ni plating were optimized to maximize the output of a betavoltaic battery using radioactive63Ni. The difference of the short circuit currents between the pre- and postdeposition of63Ni on the PN junction was 90 nA at theI-Vcharacteristics. It is suspected that the beta rays emitted from63Ni did not deeply penetrate into the PN junction due to a Ni seed layer with a thickness of 500 Å. To increase the penetration of the beta rays, electroless Ni plating was carried out on the PN junction without a seed layer. To establish the electroless coating conditions for63Ni, nonradioactive Ni was deposited onto a Si wafer without flaws on the surface. This process can be applied for electroless Ni plating on a PN junction semiconductor using radioactive63Ni in further studies.