Investigation of the Boron removal effect induced by 5.5 MeV electrons on highly doped EPI- and Cz-silicon

This study focuses on the properties of the B<math altimg="si213.svg" display="inline" id="d1e2401"><msub><mrow/><mrow><mtext>i</mtext></mrow></msub></math>O<math altimg="si213.svg" display="inline" id="d1e2409"><msub><mrow/><mrow><mtext>i</mtext></mrow></msub></math> (interstitial Boron–interstitial Oxygen) and C<math altimg="si213.svg" display="inline" id="d1e2417"><msub><mrow/><mrow><mtext>i</mtext></mrow></msub></math>O<math altimg="si213.svg" display="inline" id="d1e2426"><msub><mrow/><mrow><mtext>i</mtext></mrow></msub></math> (interstitial Carbon–interstitial Oxygen) defect complexes by 5.5MeV electrons in low resistivity silicon. Two different types of diodes manufactured on p-type epitaxial and Czochralski silicon with a resistivity of about 10 <math altimg="si5.svg" display="inline" id="d1e2436"><mrow><mi mathvariant="normal">Ω</mi><mi>⋅</mi></mrow></math>cm were irradiated with fluence values between 1 × 10<sup loc="post">15</sup>cm<sup loc="post">-2</sup> and 6 × 10<sup loc="post">15</sup>cm<sup loc="post">-2</sup>. Such diodes cannot be fully depleted and thus the accurate evaluation of defect concentrations and properties (activation energy, capture cross-section, concentration) from Thermally Stimulated Currents (TSC) experiments alone is not possible. In this study we demonstrate that by performing Thermally Stimulated Capacitance (TS-Cap) experiments in similar conditions to TSC measurements and developing theoretical models for simulating both types of B<math altimg="si213.svg" display="inline" id="d1e2459"><msub><mrow/><mrow><mtext>i</mtext></mrow></msub></math>O<math altimg="si213.svg" display="inline" id="d1e2467"><msub><mrow/><mrow><mtext>i</mtext></mrow></msub></math> signals generated in TSC and TS-Cap measurements, accurate evaluations can be performed. The changes of the position-dependent electric field, the effective space charge density <math altimg="si203.svg" display="inline" id="d1e2476"><msub><mrow><mi>N</mi></mrow><mrow><mtext>eff</mtext></mrow></msub></math> profile as well as the occupation of the B<math altimg="si213.svg" display="inline" id="d1e2486"><msub><mrow/><mrow><mtext>i</mtext></mrow></msub></math>O<math altimg="si213.svg" display="inline" id="d1e2494"><msub><mrow/><mrow><mtext>i</mtext></mrow></msub></math> defect during the electric field dependent electron emission, are simulated as a function of temperature. The macroscopic properties (leakage current and <math altimg="si203.svg" display="inline" id="d1e2502"><msub><mrow><mi>N</mi></mrow><mrow><mtext>eff</mtext></mrow></msub></math>) extracted from current–voltage and capacitance–voltage measurements at 20°C are also presented and discussed.