title: Tensile-strained Ge/SiGe quantum-well photodetectors on silicon substrates with extended infrared response.
abstract: We report on tensile-strained Ge/Si0.11Ge0.89quantum-well (QW) metal-semiconductor-metal (MSM) photodetectors on Si substrates. A tensile strain of 0.21% is introduced into the Ge wells by growing the QW stack on in-situ annealed Ge-on-Si virtual substrates (VS). The optical characterization of Ge/Si0.11Ge0.89QW MSM photodetectors indicates that the optical response increases to a wavelength of 1.5 μm or higher owing to the strain-induced direct bandgap shrinkage. Analysis of the band structure by using a k · p model suggests that by optimizing the tensile strain and Ge well width, tensile-strained Ge/SiGe QW photodetectors can be designed to cover the telecommunication C-band and beyond for optical telecommunications and on-chip interconnection.
authors: Guo-En
authors: GE
authors: Chang
authors: Shao-Wei
authors: SW
authors: Chen
authors: H H
authors: HH
authors: Cheng