Abstract
Strained GeSn alloys are promising for realizing light emitters based entirely on group IV elements. Here, we report GeSn microdisk lasers encapsulated with a SiNx stressor layer to produce tensile strain. A 300 nm-thick GeSn layer with 5.4 at% Sn, which is an indirect-bandgap semiconductor as-grown, is transformed via tensile strain engineering into a direct-bandgap semiconductor that supports lasing. In this approach, the low Sn concentration enables improved defect engineering and the tensile strain delivers a low density of states at the valence band edge, which is the light hole band. We observe ultra-low-threshold continuous-wave and pulsed lasing at temperatures up to 70 K and 100 K, respectively. Lasers operating at a wavelength of 2.5 μm have thresholds of 0.8 kW cm−2 for nanosecond pulsed optical excitation and 1.1 kW cm−2 under continuous-wave optical excitation. The results offer a path towards monolithically integrated group IV laser sources on a Si photonics platform.
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Data availability
The data that support the plots within this paper and other findings of this study are available from the corresponding authors upon reasonable request.
Code availability
Finite-element modelling was performed using commercially available COMSOL software. All other calculation codes were used in published works where model details are provided. The codes are not publicly available; any requests should be sent to the corresponding authors.
References
Soref, R. A., Buca, D. & Yu, S.-Q. Group IV photonics—driving integrated optoelectronics. Opt. Photon. News 27, 32–39 (2016).
Thomson, D. et al. Roadmap on silicon photonics. J. Opt. 18, 073003 (2016).
Wirths, S. et al. Lasing in direct-bandgap GeSn alloy grown on Si. Nat. Photon. 9, 88–92 (2015).
Stange, D. et al. Optically pumped GeSn microdisk lasers on Si. ACS Photon. 3, 1279–1285 (2016).
Reboud, V. et al. Optically pumped GeSn micro-disks with 16% Sn lasing at 3.1 μm up to 180 K. Appl. Phys. Lett. 111, 092101 (2017).
Al-Kabi, S. et al. An optically pumped 2.5 μm GeSn laser on Si operating at 110 K. Appl. Phys. Lett. 109, 171105 (2016).
Thai, Q. M. et al. GeSn heterostructure micro-disk laser operating at 230 K. Opt. Express 26, 32500–32508 (2018).
Hodgkinson, J. & Tatam, R. P. Optical gas sensing: a review. Meas. Sci. Technol. 24, 012004 (2013).
Sieger, M. & Mizaikoff, B. Toward on-chip mid-infrared sensors. Anal. Chem. 88, 5562–5573 (2016).
Singh, V. et al. Mid-infrared materials and devices on a Si platform for optical sensing. Sci. Technol. Adv. Mater. 15, 014603 (2014).
Razeghi, M. & Nguyen, B.-M. Advances in mid-infrared detection and imaging: a key issues review. Rep. Prog. Phys. 77, 82401 (2014).
Dou, W. et al. Optically pumped lasing at 3 μm from compositionally graded GeSn with tin up to 22.3%. Opt. Lett. 43, 4558–4561 (2018).
Zhou, Y. et al. Optically pumped GeSn lasers operating at 270 K with broad waveguide structures on Si. ACS Photon. 6, 1434–1441 (2019).
Rainko, D. et al. Impact of tensile strain on low Sn content GeSn lasing. Sci. Rep. 9, 259 (2019).
Gencarelli, F. et al. Crystalline properties and strain relaxation mechanism of CVD grown GeSn. ECS Trans. 50, 875–883 (2013).
Dou, W. et al. Investigation of GeSn strain relaxation and spontaneous composition gradient for low-defect and high-Sn alloy growth. Sci. Rep. 8, 5640 (2018).
Stange, D. et al. GeSn/SiGeSn heterostructure and multi quantum well lasers. ACS Photon. 5, 4628–4636 (2018).
Du, W. et al. Study of Si-based GeSn optically pumped lasers with micro-disk and ridge waveguide structures. Front. Phys. 7, 147 (2019).
Minamisawa, R. et al. Top-down fabricated silicon nanowires under tensile elastic strain up to 4.5%. Nat. Commun. 3, 1096 (2012).
El Kurdi, M. et al. Direct band gap germanium microdisks obtained with silicon nitride stressor layers. ACS Photon. 3, 443–448 (2016).
Virgilio, M., Manganelli, C. L., Grosso, G., Pizzi, G. & Capellini, G. Radiative recombination and optical gain spectra in biaxially strained n-type germanium. Phys. Rev. B 87, 235313 (2013).
Bao, S. et al. Low-threshold optically pumped lasing in highly strained germanium nanowires. Nat. Commun. 8, 1845 (2017).
Süess, M. J. et al. Analysis of enhanced light emission from highly strained germanium microbridges. Nat. Photon. 7, 466–472 (2013).
Armand Pilon, F. T. et al. Lasing in strained germanium microbridges. Nat. Commun. 10, 2724 (2019).
Ghrib, A. et al. Control of tensile strain in germanium waveguides through silicon nitride layers. Appl. Phys. Lett. 100, 201104 (2012).
Capellini, G. et al. Strain analysis in SiN/Ge microstructures obtained via Si-complementary metal oxide semiconductor compatible approach. J. Appl. Phys. 113, 013513 (2013).
von den Driesch, N. et al. Direct bandgap group IV epitaxy on Si for laser applications. Chem. Mater. 27, 4693–4702 (2015).
Ghrib, A. et al. All-around SiN stressor for high and homogeneous tensile strain in germanium microdisk cavities. Adv. Opt. Mater. 3, 353–358 (2015).
Zaumseil, P. et al. The thermal stability of epitaxial gesn layers. Appl. Phys. Lett. Mater. 6, 076108 (2018).
Elbaz, A. et al. Solving thermal issues in tensile-strained Ge microdisks. Opt. Express 26, 28376–28384 (2018).
Elbaz, A. et al. Germanium microlasers on metallic pedestals. APL Photon. 3, 106102 (2018).
Uchida, N. et al. Carrier and heat transport properties of polycrystalline GeSn films on SiO2. Appl. Phys. Lett. 10, 232105 (2015).
Pezzoli, F., Giorgioni, A., Patchett, D. & Myronov, M. Temperature-dependent photoluminescence characteristics of GeSn epitaxial layers. ACS Photon. 3, 2004–2009 (2016).
Cheng, R. et al. Relaxed and strained patterned germanium-tin structures: a Raman scattering study. ECS J. Solid State Sci. Technol. 2, P138–P145 (2013).
Rabolt, J. F. & Bellar, R. The nature of apodization in Fourier transform spectroscopy. Appl. Spectrosc. 35, 132–135 (1981).
El Kurdi, M. et al. Tensile-strained germanium microdisks with circular Bragg reflectors. Appl. Phys. Lett. 108, 091103 (2016).
Sargent, M. Theory of a multimode quasiequilibrium semiconductor laser. Phys. Rev. A 48, 717–726 (1993).
Stange, D. et al. Short-wave infrared leds from GeSn/SiGeSn multiple quantum wells. Optica 4, 185–188 (2017).
Ghrib, A. et al. Tensile-strained germanium microdisks. Appl. Phys. Lett. 102, 221112 (2013).
Prost, M. et al. Tensile-strained germanium microdisk electroluminescence. Opt. Express 23, 6722–6730 (2015).
Wang, Z. et al. Novel light source integration approaches for silicon photonics. Laser Photon. Rev. 11, 1700063 (2017).
Seifried, M. et al. Monolithically integrated CMOS-compatible III–V on silicon lasers. IEEE J. Select. Top. Quant. Electron. 24, 1–9 (2018).
Acknowledgements
M.E.K. and A.E. thank R. Colombelli and A. Bousseksou for discussions and their help with mounting the PL set-up with the FTIR spectrometer. We thank G. Mussler for XRD measurements. This work used knowledge acquired in the collaboration with H. Sigg from PSI. This work was supported by the French RENATECH network, the French National Research Agency (Agence Nationale de la Recherche, ANR) through funding of the ELEGANTE project (ANR-17-CE24-0015) and the Deutsche Forschungsgemeinschaft (DFG) via the project ‘SiGeSn Laser for Silicon Photonics’. A.E. was supported by ANRT through a CIFRE grant. A.F. acknowledges funding within the ANR-16-CE09-0029-03 TIPTOP project.
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All authors contributed to the work. P.B., M.E.K. and A.E. designed the device structure. M.E.K. and A.E. performed the strained disks fabrication with E.H., I.S., K.P. and G.P. M.E.K. and A.E. performed the PL measurements and laser experiments with N.Z. and X.C. K.P., G.P., I.S., N.v.d.D. and D.B. performed the structural analysis of the material. The GeSn layer was grown by D.B. and N.v.d.D. on substrates from J.-M.H. The Raman analyses were performed by A.F. and R.O. P.B., S.S. and Z.I. contributed to the modelling with M.E.K. and D.B. The work was supervised by D.G., F.B., P.B., D.B. and M.E.K. P.B., M.E.K., N.v.d.D., D.G. and D.B. wrote the manuscript.
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Elbaz, A., Buca, D., von den Driesch, N. et al. Ultra-low-threshold continuous-wave and pulsed lasing in tensile-strained GeSn alloys. Nat. Photonics 14, 375–382 (2020). https://doi.org/10.1038/s41566-020-0601-5
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DOI: https://doi.org/10.1038/s41566-020-0601-5
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