Recombination centers in electron‐irradiated Czochralski silicon solar cells

The defect responsible for the minority‐carrier lifetime in p‐type Czochralski silicon introduced by electron irradiation has been detected and characterized by deep‐level transient spectroscopy and spin‐dependent recombination. From the isotropic g value (2.0055), the defect is tentatively identified as a Si dangling bond originating from a vacancy cluster. Its energetic location in the gap is at 630 meV below the conduction band. The electron and hole cross sections and their variation with temperature have been determined, and found to account for the minority‐carrier lifetime of the material.