NATURE OF P-B-LIKE DANGLING-ORBITAL CENTERS IN LUMINESCENT POROUS SILICON

The P(b)-like dangling-orbit centers in luminescent porous silicon (LP Si) have been enhanced to very high concentration (10(15) cm-2) by gen tle oxidation. High signal-to-noise ratio and very sharp lines enable the g-value maps, and Si-29 hyperfine and superhyperfine structures to be clearly resolved by ordinary EPR. Only one P(b)-like center is obs erved, and it is proven to be of the P(b0) variety (.Si=Si3). The rela tive EPR signal strengths from different g limbs indicate that the LPS i crystallite morphology is not dominated by needles or platelets.