Nature of Pb‐like dangling‐orbital centers in luminescent porous silicon

The Pb‐like dangling‐orbit centers in luminescent porous silicon (LPSi) have been enhanced to very high concentration (1015 cm−2) by gentle oxidation. High signal‐to‐noise ratio and very sharp lines enable the g‐value maps, and 29Si hyperfine and superhyperfine structures to be clearly resolved by ordinary EPR. Only one Pb‐like center is observed, and it is proven to be of the Pb0 variety (⋅Si≡Si3). The relative EPR signal strengths from different g limbs indicate that the LPSi crystallite morphology is not dominated by needles or platelets.