Electroluminescence from mechanically damaged oxidized silicon

Abstract

We have found significant electroluminescence (EL), clearly visible in room light, to be produced from lightly oxidized Si wafers, which have been mechanically scratched, or indented with a diamond tip. The EL occurs in the visible and infrared ranges. Undamaged oxidized samples, where the oxide is chemically thinned to allow current from a top contact to pass, also show similar EL. However, damaged Si wafers that have only normal thin or no oxide, show negligible EL. A search for quantum-confined particles in indentation pits by scanning tunneling microscopy does not show any present. The results point strongly to the EL mechanism being related to the damage creating areas of optimum oxide thickness. The results are compared with those from spark-processed and laser-grooved silicon.

Visible electroluminescence from native SiO2 on n-type Si substrates

“…6 This visible EL is also similar to that from lightly spark processed Si, mechanically damaged SiO 2 /Si, and laser-grooved Si. [10][11][12] Similar experiments on a p-type sample with native oxide gave similar emission, but EL only occurred under forward biased conditions. This is to say that in p and n cases, for visible EL to occur, the top metal electrode must be negatively biased, i.e., electrons must be injected into the Si wafer from the metal electrode.…”

Photoluminescence Spectroscopy of Silica-Based Mesoporous Materials

“…Note that the PL induced from MSs is very similar to those from surface-oxidized silicon nanocrystals 34 and porous silicon, [35][36][37][38][39][40] indicating that the nature of light emitters is the same. However, the comparative analysis of the PL properties of MSs and silicon nanoscales requires a separate consideration and lies beyond the scope of the current paper.…”

“…Note that the spectroscopic properties that will be discussed for MSs are closely related to those of silicon−hydrogen alloy films and porous silicon. − It is known that PL from these materials is the object of much concentrated attention for nanoscale electronics, but the origin of emission has not yet been completely clarified. Therefore, the study of MSs is also of profound importance for silicon-based electronic technology.…”