Configurally metastable defect in irradiated epitaxially grown boron doped p-type Si

In this work, we investigate the metastability of the defect Hα2 introduced in epitaxially grown boron-doped p-type Si by high energy (5.4 MeV) He-ion irradiation. Deep level transient spectroscopy (DLTS) and thermally stimulated capacitance (TSCAP) measurements were used to study the electronic properties of the defect in each configuration. The analyses indicate that this metastable defect can exist in either of two configurations (A or B) and can be reversibly transformed using conventional bias-on/bias-off annealing temperature cycles. The energy barriers for transition between these two configurations (A to B and B to A) are determined as 0.79 and 0.52 eV, respectively. In addition, we have compared the electronic properties of Hα2 to those introduced during high-energy (12 MeV) electron irradiation and 250 keV proton irradiation. It is shown that defect HE2 introduced during electron irradiation of the same epitaxially grown p-Si and a defect HP2 introduced during 250 keV proton-irradiated boron doped float-zone (FZ) p-Si exhibit the same metastability as Hα2 and provide further evidence that Hα2 is hydrogen-related metastable defect.