Metastable-defect behaviors of iron-boron Pairs in silicon using recombination-enhanced defect reaction

When iron diffuses into p-type silicon doped with boron, positively charged interstitial iron is captured by negatively charged substitutional boron, thus forming a stable pair between iron at the first nearest-neighbor site and boron. If minority-carrier injection is carried out at low temperature, iron absorbs the recombination energy and migrates from the first nearest site to another site. Thus, a structurally metastable pair is created, which cannot be established under the thermal equilibrium condition. We report the determination of impurity states and migration behaviors of iron in the vicinity of boron using transient capacitance techniques.