Pressure Dependence of a Deep Excitonic Level in Silicon

Certain optically active defects in silicon provide a unique opportunity to observe, in detail, the effect of hydrostatic pressure on a deep level. We present a photoluminescence (5 – 100K) study of one such defect, the I, radiation-damage center, under high hydrostatic pressures (1–50 kbar). While the energy variation of this level indicates the expected mutli-band nature typical of a deep level, a severe and continuous reduction in the observed luminescence intensity was also observed. Temperature dependence, time resolved photoluminescence, and photoluminescence excitation spectroscopy are employed to attempt to discern the mechanism involved.