Electrically detected double electron–electron resonance: exchange interaction of P donors and P defects at the Si/SiO interface

Abstract

We study the coupling of P dangling bond defects at the Si/SiO₂ interface and ³¹P donors in an epitaxial layer directly underneath using electrically detected double electron–electron resonance (EDDEER). An exponential decay of the EDDEER signal is observed, which is attributed to a broad distribution of exchange coupling strengths J/2π from 25 kHz to 3 MHz. Comparison of the experimental data with a numerical simulation of the exchange coupling shows that this range of coupling strengths corresponds to ³¹P–P distances ranging from 14 nm to 20 nm.

Keywords:

• EDMR
• DEER
• phosphorus donors
• dangling bonds
• exchange coupling

Acknowledgements

The work was supported by DFG (Grant No. SFB 631, C3 and Grant No. SPP 1601, Br 1585/8-1) and BMBF (Grant No. EPR Solar).