Si-Based GeSn Photodetectors toward Mid-Infrared Imaging Applications

Tran, Ha Nguyen; Pham, Thach; Margetis, Joe; Zhou, Yiyin; Dou, Wei; Grant, Perry C.; Grant, Joshua M.; Al-Kabi, Sattar; Sun, Greg; Soref, Richard A.; Tolle, John; Zhang, Yong-Hang; Du, Wei; Li, Baohua; Mortazavi, Mansour; Yu, Shui Qing

doi:10.1021/acsphotonics.9b00845

Cited by 177 publications

(116 citation statements)

References 45 publications

Supporting

Mentioning

108

Contrasting

Order By: Relevance

“…The higher leakage current in GeSn is believed to originate from the presence of point defects, such as vacancies and vacancy complexes, [ 52 ] which have been suggested to be responsible for the unintentional p‐type doping in GeSn that is an order of magnitude higher than in epitaxial Ge. [ 55–57 ] It is worth mentioning that other factors could play a role in the measured dark current, such as the absence of a surface passivation layer [ 43 ] and the parallel conductance associated with the Ge‐VS/Si stacking. [ 58 ] Since the incident light has an achromatic spot size of ≈7 µm at the sample after the reflective objective, the photocurrent magnitude is thus independent of the larger active membrane device area.…”

Section: Resultsmentioning

confidence: 99%

“…Indeed, 3D complex membrane structures can be realized by selectively releasing to engineer lattice parameter and bandgap energy and directness. GeSn direct bandgap is achieved at a Sn content around 10 at% in fully relaxed layers, leading to the recent demonstration of room temperature optical emission up to ≈4 µm [34][35][36] and optically pumped lasers at 3.1-3.4 µm operating at temperatures of 180-270 K. [37][38][39] PDs were also demonstrated using GeSn layers showing a room temperature performance close to that of commercial PbSe detectors at wavelengths reaching 3 µm, [40][41][42][43] although the residual strain limits the operation wavelength range. Indeed, GeSn semiconductors are inherently metastable and typically exhibit a compositional gradient and a large compressive strain resulting from the canonical, lattice-mismatched growth on Ge.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

All‐Group IV Transferable Membrane Mid‐Infrared Photodetectors

Atalla

Assali

Attiaoui

et al. 2020

Adv Funct Materials

View full text Add to dashboard Cite

Semiconductor membranes emerged as a versatile class of nanomaterials to control lattice strain and engineer complex heterostructures enabling a variety of innovative applications. With this perspective, herein this platform is exploited to tune simultaneously the lattice parameter and bandgap energy in group IV GeSn semiconductor alloys. As Sn content is increased to reach a direct bandgap, these semiconductors become metastable and typically compressively strained. It is shown that the relaxation in released membranes extends the absorption wavelength range deeper in the mid-infrared. Fully released Ge 0.83 Sn 0.17 membranes are integrated on silicon and used in the fabrication of broadband photodetectors operating at room temperature with a record wavelength cutoff of 4.6 µm, without compromising the performance at shorter wavelengths down to 2.3 µm. These membrane devices are characterized by two orders of magnitude reduction in dark current as compared to as-grown strained epitaxial layers. A variety of experimental tools and optimized calculations are used to discuss the crystalline quality, composition uniformity, lattice strain, and the electronic band structure of the investigated materials and devices. The ability to engineer all-group IV transferable mid-infrared photodetectors lays the groundwork to implement scalable and flexible sensing and imaging technologies exploiting these integrative, silicon-compatible strained-relaxed GeSn membranes.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

All‐Group IV Transferable Membrane Mid‐Infrared Photodetectors

Atalla

Assali

Attiaoui

et al. 2020

Adv Funct Materials

View full text Add to dashboard Cite

show abstract

“…Assisted by a whispering-gallery cavity, a Geon-Si photodetector has achieved a responsivity of up to 0.45 A/W at 1630 nm [148]. Toward even longer wavelengths, GeSn alloys grown on silicon have attracted a lot of attention [149,150]. Recent works toward mid-IR imaging have extended the cut-off wavelength to 3.65 μm [149].…”

Section: Compatibility With Ultrawide-band Systemsmentioning

confidence: 99%

“…Toward even longer wavelengths, GeSn alloys grown on silicon have attracted a lot of attention [149,150]. Recent works toward mid-IR imaging have extended the cut-off wavelength to 3.65 μm [149]. GHz-level GeSn-on-Si photodetectors were reported with a responsivity of 0.04 A/W at 1900 nm and a dark current density of 31 mA/cm 2 [150].…”

Section: Compatibility With Ultrawide-band Systemsmentioning

confidence: 99%

Scaling capacity of fiber-optic transmission systems via silicon photonics

2020

View full text Add to dashboard Cite

The tremendous growth of data traffic has spurred a rapid evolution of optical communications for a higher data transmission capacity. Next-generation fiber-optic communication systems will require dramatically increased complexity that cannot be obtained using discrete components. In this context, silicon photonics is quickly maturing. Capable of manipulating electrons and photons on the same platform, this disruptive technology promises to cram more complexity on a single chip, leading to orders-of-magnitude reduction of integrated photonic systems in size, energy, and cost. This paper provides a system perspective and reviews recent progress in silicon photonics probing all dimensions of light to scale the capacity of fiber-optic networks toward terabits-per-second per optical interface and petabits-per-second per transmission link. Firstly, we overview fundamentals and the evolving trends of silicon photonic fabrication process. Then, we focus on recent progress in silicon coherent optical transceivers. Further scaling the system capacity requires multiplexing techniques in all the dimensions of light: wavelength, polarization, and space, for which we have seen impressive demonstrations of on-chip functionalities such as polarization diversity circuits and wavelength- and space-division multiplexers. Despite these advances, large-scale silicon photonic integrated circuits incorporating a variety of active and passive functionalities still face considerable challenges, many of which will eventually be addressed as the technology continues evolving with the entire ecosystem at a fast pace.

show abstract

“…However, those characteristics are rather difficult to meet simultaneously within a single device. Most mature GeSn photodetector designs include simple p-i-n diodes in the waveguide-integrated [210,213] and free-space forms [214], MQW p-i-n photodiodes on Si [205,206,215] or Ge-oninsulator [216,217] substrates, p-n-p floating-based heterojunction phototransistors [218,219], pseudomorphic hetero-junction p-i-n diode with resonant cavity [207], and MQW APDs [220,221]. The opto-electrical performances of wavelength-extended Si-Ge photodetectors realizations still do not reach the same levels of Ge devices operating at standard fiber-optic telecommunication windows.…”

Section: Photodiodes Beyond Mainstream Wavebandsmentioning

confidence: 99%

Silicon–germanium receivers for short-wave-infrared optoelectronics and communications

et al. 2020

View full text Add to dashboard Cite

Integrated silicon nanophotonics has rapidly established itself as intriguing research field, whose outlets impact numerous facets of daily life. Indeed, nanophotonics has propelled many advances in optoelectronics, information and communication technologies, sensing and energy, to name a few. Silicon nanophotonics aims to deliver compact and high-performance components based on semiconductor chips leveraging mature fabrication routines already developed within the modern microelectronics. However, the silicon indirect bandgap, the centrosymmetric nature of its lattice and its wide transparency window across optical telecommunication wavebands hamper the realization of essential functionalities, including efficient light generation/amplification, fast electro-optical modulation, and reliable photodetection. Germanium, a well-established complement material in silicon chip industry, has a quasi-direct energy band structure in this wavelength domain. Germanium and its alloys are thus the most suitable candidates for active functions, i.e. bringing them to close to the silicon family of nanophotonic devices. Along with recent advances in silicon–germanium-based lasers and modulators, short-wave-infrared receivers are also key photonic chip elements to tackle cost, speed and energy consumption challenges of exponentially growing data traffics within next-generation systems and networks. Herein, we provide a detailed overview on the latest development in nanophotonic receivers based on silicon and germanium, including material processing, integration and diversity of device designs and arrangements. Our Review also emphasizes surging applications in optoelectronics and communications and concludes with challenges and perspectives potentially encountered in the foreseeable future.

show abstract

Si-Based GeSn Photodetectors toward Mid-Infrared Imaging Applications

Cited by 177 publications

References 45 publications

All‐Group IV Transferable Membrane Mid‐Infrared Photodetectors

All‐Group IV Transferable Membrane Mid‐Infrared Photodetectors

Scaling capacity of fiber-optic transmission systems via silicon photonics

Silicon–germanium receivers for short-wave-infrared optoelectronics and communications

Contact Info

Product

Resources

About