EFFECT OF ELECTRIC-CURRENT ON DURATION OF CLEAVAGE LUMINESCENCE

The dependence on time t of the room temperature luminescence S(t) emi tted by Si crystals cleaved in vacuum, is strongly affected by relativ ely low electric current densities passed through the specimen at the initiation Df cleavage, even though the luminescence continues long af ter the cracking is complete and the current has stopped. Above approx imately 30 mA cm(-2), there is no further effect. An empirical express ion has been obtained for S(t), having one adjustable parameter that v aries with the current density. The effects do not appear to be possib le unless cleaved surfaces attain temporary high temperatures, and poi nt to the complexity of bond rupture phenomena. (C) 1996 American Inst itute of Physics.