An investigation was made of the metastability of the Hα2 defect which was introduced into epitaxially grown B-doped p-type material by high-energy (5.4MeV) He-ion irradiation. Deep-level transient spectroscopic and thermally stimulated capacitance measurements were used to study the electronic properties of the defect in each configuration. The analyses indicated that this metastable defect could exist in A or B configurations and could be reversibly transformed by using conventional bias-on/bias-off annealing cycles. The energy barriers for transitions between these configurations were determined to be 0.79eV (A > B) and 0.52eV (B > A). The electronic properties of Hα2 were compared with those introduced during high-energy (12MeV) electron irradiation and 250keV proton irradiation. It was shown that the HE2 defect which was introduced during electron irradiation of epitaxially grown p-type material, and the HP2 defect which was introduced during the 250keV proton irradiation of B-doped float-zone p-type material, exhibited the same metastability as Hα2. This provided further evidence that Hα2 was a H-related metastable defect.

Configurationally Metastable Defects in Irradiated Epitaxially Grown Boron-Doped p-Type Si. M.Mamor, M.Willander, F.D.Auret, W.E.Meyer, E.Sveinbjörnsson: Physical Review B, 2001, 63[4], 045201 (5pp)