Photoluminescence of hydrogenated SimGen superlattices

Abstract

The effect of hydrogen passivation on the photoluminescence of Si-rich superlattices is investigated. The as-grown samples show many defect-related luminescence signals and several additional luminescence peaks believed to originate from the superlattice. The background luminescence along with the dislocation and defect lines are found to be passivated by the hydrogen atoms. The intensity of the superlattice peak increases after passivation and its phonon replica, initially submerged in the background and defect luminescence signals, is highlighted. After a subsequent temperature annealing in N2, the background luminescence is increased as hydrogen outdiffuses but the superlattice main peak decreases, perhaps due to the change of the carrier lifetime.

Enhancement of photoluminescence by microdisk formation from Si/Ge/Si single quantum wells

“…6,11 As shown in Fig. 2, two peaks at 0.972 and 0.920 eV are believed to be attributed to a NP transition and an associated phonon replica involving a (TO Si-Si ) mode, respectively.…”

Uniform SiGe/Si quantum well nanorod and nanodot arrays fabricated using nanosphere lithography

“…One important approach is the combination of Si with other semiconductor materials, such as Ge or Si 1 − x Ge x alloys for heterostructures. For this purpose, Si/Ge superlattices (SLs) [21], multiple quantum wells (MQWs) [22], and multiple quantum dots (MQDs) [23] have been demonstrated to adjust the bandgap and reduce nonradiative recombination. Choi et al further reported that the formation of microdisks from the Si/Ge/Si single QW using electron beam lithography significantly enhanced the intrinsic photoluminescence (PL) transitions [9].…”

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