Accumulated sidewall damage in dry etched photonic crystalsShow others and affiliations
2009 (English)In: Journal of Vacuum Science & Technology B, ISSN 1071-1023, E-ISSN 1520-8567, Vol. 27, no 4, p. 1969-1975Article in journal (Refereed) Published
Abstract [en]
Evidence for accumulated damage is provided by investigating the effect of etch duration on the carrier lifetime of an InGaAsP quantum well (QW) inside the InP-based photonic crystal (PhC) structures. It is found that once the quantum well is etched through, additional etching reduces the carrier lifetimes from 800 to 70 ps. The surface recombination velocity (SRV) at the exposed hole sidewalls is determined from the measured carrier lifetimes of the PhC fields with different lattice parameters. The observed variation in the SRV with etch duration also confirms the presence of accumulated sidewall damage. It increases from 6x10(3) to 1.2x10(5) cm s(-1) as the etching time increases from 3 to 50 min. A geometric model based on sputtering theory and on the evolution of the hole shape is developed to explain the accumulation of sidewall damage. The model is used to estimate the number of impact events from sputtered species reaching the QW sidewalls, and the variation in the accumulated impact events with etch duration is shown to be qualitatively consistent with the experimental observations. Finally, the results suggest a new method for tailoring the carrier lifetimes in PhC membrane structures.
Place, publisher, year, edition, pages
2009. Vol. 27, no 4, p. 1969-1975
Keywords [en]
carrier lifetime, etching, gallium arsenide, gallium compounds, III-V, semiconductors, indium compounds, photonic crystals, semiconductor, quantum wells, surface recombination, inp, energy, dependence, nanocavity, laser, gaas
Identifiers
URN: urn:nbn:se:kth:diva-18647DOI: 10.1116/1.3179256ISI: 000268535600036Scopus ID: 2-s2.0-68349133798OAI: oai:DiVA.org:kth-18647DiVA, id: diva2:336694
Note
QC 20100525
2010-08-052010-08-052022-09-13Bibliographically approved