Interplay between strain and thickness on effective carrier lifetime of buffer mediated epitaxial germanium probed by photoconductance decay technique
dc.contributor.author | Bhattacharya, Shuvodip | en |
dc.contributor.author | Johnston, Steve | en |
dc.contributor.author | Datta, Suman | en |
dc.contributor.author | Hudait, Mantu K. | en |
dc.date.accessioned | 2025-03-03T14:06:17Z | en |
dc.date.available | 2025-03-03T14:06:17Z | en |
dc.date.issued | 2023-05-19 | en |
dc.description.abstract | We report contactless effective minority carrier lifetime of epitaxially grown unstrained and in-plane <110> biaxially tensile-strained (001) germanium (ϵ-Ge) epilayers measured using microwave-reflectance photoconductance decay measurements. Strained Ge epilayers were grown using InxGa1-xAs linearly graded buffers on (001) GaAs substrates. Using homogeneous excitation of unstrained Ge epilayers, thickness-dependent separation of minority carrier lifetime components under low injection conditions yielded a bulk lifetime of 114 ± 2 ns and low surface recombination velocity of 21.3 ± 0.04 cm/s. More notably, an effective minority carrier lifetime of >100 ns obtained from sub-50 nm 1.6% tensile-strained Ge epilayers showed no degradation relative to the unstrained counterpart. Detailed material characterization using X-ray diffractometry revealed successful strain transfer of 0.61 and 0.89% to the Ge epilayers via InxGa1-xAs metamorphic buffers and confirms pseudomorphic growth. Lattice coherence observed at the ϵ-Ge epilayer and InxGa1-xAs buffer heterointerfaces via transmission electron microscopy substantiates the prime material quality achieved. The relatively high carrier lifetimes achieved are an indicator of excellent material quality and provide a path forward to realize low-threshold Ge laser sources. | en |
dc.description.version | Accepted version | en |
dc.format.extent | Pages 3190-3197 | en |
dc.format.mimetype | application/pdf | en |
dc.identifier.doi | https://doi.org/10.1021/acsaelm.3c00256 | en |
dc.identifier.eissn | 2637-6113 | en |
dc.identifier.issn | 2637-6113 | en |
dc.identifier.issue | 6 | en |
dc.identifier.orcid | Hudait, Mantu [0000-0002-9789-3081] | en |
dc.identifier.uri | https://hdl.handle.net/10919/124761 | en |
dc.identifier.volume | 5 | en |
dc.language.iso | en | en |
dc.publisher | American Chemical Society | en |
dc.relation.uri | https://pubs.acs.org/doi/10.1021/acsaelm.3c00256 | en |
dc.rights | In Copyright | en |
dc.rights.uri | http://rightsstatements.org/vocab/InC/1.0/ | en |
dc.subject | germanium | en |
dc.subject | carrier lifetime | en |
dc.subject | tensile strain | en |
dc.subject | molecular beam epitaxy | en |
dc.subject | x-ray diffraction | en |
dc.subject | photoconductance | en |
dc.subject | bulk lifetime | en |
dc.subject | surface recombinationvelocity | en |
dc.title | Interplay between strain and thickness on effective carrier lifetime of buffer mediated epitaxial germanium probed by photoconductance decay technique | en |
dc.title.serial | ACS Applied Electronic Materials | en |
dc.type | Article - Refereed | en |
dc.type.dcmitype | Text | en |
dc.type.other | Article | en |
pubs.organisational-group | Virginia Tech | en |
pubs.organisational-group | Virginia Tech/Engineering | en |
pubs.organisational-group | Virginia Tech/Engineering/Electrical and Computer Engineering | en |
pubs.organisational-group | Virginia Tech/All T&R Faculty | en |
pubs.organisational-group | Virginia Tech/Engineering/COE T&R Faculty | en |