Prof. Kazumi Wada Profile

Prof. Kazumi Wada

Research Scientist at Massachusetts Institute of Technology

SPIE Involvement:

Conference Chair | Editor | Author

Proceedings Article | 25 October 2018 Paper

Reduction of threading dislocations by image force in Ge selective epilayers on Si

M. Yako, Y. Ishikawa, E. Abe, K. Wada

Proceedings Volume 10823, 108230F (2018) https://doi.org/10.1117/12.2501081

KEYWORDS: Germanium, Silicon, Transmission electron microscopy, Atomic force microscopy, Photonic devices, Scanning transmission electron microscopy, Argon

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Proceedings Article | 22 February 2018 Paper

Broadband athermal waveguides and devices for datacom and telecom applications

Liuqing He, Yuhao Guo, Zhaohong Han, Kazumi Wada, Lionel Kimerling, Jurgen Michel, Anuradha Agarwal, Guifang Li, Lin Zhang

Proceedings Volume 10537, 105371S (2018) https://doi.org/10.1117/12.2291292

KEYWORDS: Waveguides, Silicon, Resonators, Cladding, Microrings, Optoelectronics, Data communications, Polymers, Integrated photonics, Silicon photonics

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Proceedings Article | 17 November 2016 Paper

Defect-free fabrication of nano-disk and nano-wire by fusion of bio-template and neutral beam etching

S. Samukawa, Shuichi Noda, Akio Higo, Manabu Yasuda, Kazumi Wada

Proceedings Volume 10027, 100270Q (2016) https://doi.org/10.1117/12.2247702

KEYWORDS: Nanowires, Etching, Nanolithography, Luminescence, Germanium, Silicon, Gallium arsenide, Iron, Ions, Plasma

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Proceedings Article | 27 July 2016 Presentation

Subwavelength engineered fiber-to-chip silicon-on-sapphire interconnects for mid-infrared applications (Conference Presentation)

Carlos Alonso-Ramos, Zhaohong Han, Xavier Le Roux, Hongtao Lin, Vivek Singh, Pao Tai Lin, Dawn Tan, Eric Cassan, Delphine Marris-Morini, Laurent Vivien, Kazumi Wada, Juejun Hu, Anuradha Agarwal, Lionel C. Kimerling

Proceedings Volume 9891, 98911J (2016) https://doi.org/10.1117/12.2229350

KEYWORDS: Mid-IR, Silicon, Silicon photonics, Sensors, Absorption spectroscopy, Photonic integrated circuits, Sapphire, Lab on a chip

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The mid-Infrared wavelength range (2-20 µm), so-called fingerprint region, contains the very sharp vibrational and rotational resonances of many chemical and biological substances. Thereby, on-chip absorption-spectrometry-based sensors operating in the mid-Infrared (mid-IR) have the potential to perform high-precision, label-free, real-time detection of multiple target molecules within a single sensor, which makes them an ideal technology for the implementation of lab-on-a-chip devices. Benefiting from the great development realized in the telecom field, silicon photonics is poised to deliver ultra-compact efficient and cost-effective devices fabricated at mass scale. In addition, Si is transparent up to 8 µm wavelength, making it an ideal material for the implementation of high-performance mid-IR photonic circuits. The silicon-on-insulator (SOI) technology, typically used in telecom applications, relies on silicon dioxide as bottom insulator. Unfortunately, silicon dioxide absorbs light beyond 3.6 µm, limiting the usability range of the SOI platform for the mid-IR. Silicon-on-sapphire (SOS) has been proposed as an alternative solution that extends the operability region up to 6 µm (sapphire absorption), while providing a high-index contrast. In this context, surface grating couplers have been proved as an efficient means of injecting and extracting light from mid-IR SOS circuits that obviate the need of cleaving sapphire. However, grating couplers typically have a reduced bandwidth, compared with facet coupling solutions such as inverse or sub-wavelength tapers. This feature limits their feasibility for absorption spectroscopy applications that may require monitoring wide wavelength ranges. Interestingly, sub-wavelength engineering can be used to substantially improve grating coupler bandwidth, as demonstrated in devices operating at telecom wavelengths. Here, we report on the development of fiber-to-chip interconnects to ZrF4 optical fibers and integrated SOS circuits with 500 nm thick Si, operating around 3.8 µm wavelength. Results on facet coupling and sub-wavelength engineered grating coupler solutions in the mid-IR regime will be compared.

Proceedings Article | 3 April 2015 Paper

Photoluminescence quenching effect by Si cap in n+ Ge on Si

H. Pan, R. Takahashi, K. Takinai, K. Wada

Proceedings Volume 9367, 93671E (2015) https://doi.org/10.1117/12.2078593

KEYWORDS: Germanium, Silicon, Luminescence, Interfaces, Oxides, Doping, Thermal oxidation, Reactive ion etching, Etching, Oxidation

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Proceedings Article | 27 February 2015 Paper

Strain tuning of germanium bandgap by selective epitaxial growth for electro-absorption modulators

Y. Mizuno, M. Yako, N. Luan, K. Wada

Proceedings Volume 9367, 93670E (2015) https://doi.org/10.1117/12.2080449

KEYWORDS: Germanium, Silica, Waveguides, Silicon, Modulators, Photomasks, Absorption, Finite element methods, Modulation, Scanning electron microscopy

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Proceedings Article | 13 November 2014 Paper

GeSi photonics for telecommunication applications

Papichaya Chaisakul, Vladyslav Vakarin, Delphine Marris-Morini, Jacopo Frigerio, Kazumi Wada, Giovanni Isella, Laurent Vivien

Proceedings Volume 9277, 92770E (2014) https://doi.org/10.1117/12.2071507

KEYWORDS: Waveguides, Germanium, Silicon, Photonics, Quantum wells, Integrated optics, Active optics, Cladding, Wave propagation, Telecommunications

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Proceedings Article | 6 March 2013 Paper

Silicon, silica, and germanium photonic integration for electronic and photonic convergence

Hiroshi Fukuda, Tai Tsuchizawa, Hidetaka Nishi, Rai Kou, Tatsurou Hiraki, Kotarou Takeda, Kazumi Wada, Yasuhiko Ishikawa, Koji Yamada

Proceedings Volume 8628, 862806 (2013) https://doi.org/10.1117/12.2006691

KEYWORDS: Silicon, Waveguides, Polarization, Germanium, Silicon photonics, Silica, Photon polarization, Refractive index, Photonic devices, Photonic integrated circuits

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Proceedings Article | 17 February 2010 Paper

Integrated photonic devices based on silicon photonic wire waveguide platform

Koji Yamada, Hiroshi Fukuda, Tai Tsuchizawa, Toshifumi Watanabe, Hiroyuki Shinojima, Hidetaka Nishi, Songbong Park, Yasuhiko Ishikawa, Kazumi Wada, Sei-ichi Itabashi

Proceedings Volume 7606, 76060T (2010) https://doi.org/10.1117/12.840889

KEYWORDS: Waveguides, Polarization, Silicon photonics, Germanium, Silicon, Optical fibers, Photodiodes, Signal attenuation, Integrated photonics, Photonic devices

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Proceedings Article | 19 November 2007 Paper

Si photonics: past, present, and future

Kazumi Wada

Proceedings Volume 6782, 678202 (2007) https://doi.org/10.1117/12.754560

KEYWORDS: Transistors, Silicon, Germanium, Waveguides, Logic, Binary data, Optical interconnects, Switches, Photodetectors, Silica

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Proceedings Article | 1 July 2004 Paper

Electronics and photonics convergence on Si CMOS platform

Kazumi Wada

Proceedings Volume 5357, (2004) https://doi.org/10.1117/12.533807

KEYWORDS: Silicon, Germanium, Photonics, Electronics, Waveguides, Photodetectors, Absorption, Clocks, Wavelength division multiplexing, Silicon photonics

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Proceedings Article | 28 May 2004 Paper

Air trench waveguide bend for high-density optical integration

Shoji Akiyama, Kazumi Wada, Jurgen Michel, Lionel Kimerling, Milos Popovic, Hermann Haus

Proceedings Volume 5355, (2004) https://doi.org/10.1117/12.529630

KEYWORDS: Waveguides, Cladding, Wave propagation, Finite-difference time-domain method, Silica, Integrated optics, Fabry–Perot interferometers, Refractive index, Photonic integrated circuits, Fiber couplers

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Proceedings Article | 1 July 2003 Paper

Monolithic Si-based technology for optical receiver circuits

Douglas Cannon, H.-C. Luan, David Danielson, Samerkhae Jongthammanurak, Jifeng Liu, Jurgen Michel, Kazumi Wada, Lionel Kimerling

Proceedings Volume 4999, (2003) https://doi.org/10.1117/12.482504

KEYWORDS: Germanium, Silicon, Photodetectors, Waveguides, Sensors, Annealing, Receivers, Optical circuits, Diodes, Absorption

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Proceedings Article | 11 July 2002 Paper

On-chip interconnection beyond semiconductor roadmap: silicon microphotonics

Kazumi Wada, Hsin-Chiao Luan, Desmond Lim, Lionel Kimerling

Proceedings Volume 4870, (2002) https://doi.org/10.1117/12.475558

KEYWORDS: Silicon, Germanium, Waveguides, Clocks, Sensors, Semiconductors, Optical clocks, Resonators, Metals, Absorption

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Proceedings Article | 18 June 2002 Paper

Micron-size bending radii in silica-based waveguides

Milos Popovic, Kazumi Wada, Shoji Akiyama, Hermann Haus, Jurgen Michel

Proceedings Volume 4640, (2002) https://doi.org/10.1117/12.433272

KEYWORDS: Cladding, Waveguides, Silica, Silicon, Finite-difference time-domain method, Plasma enhanced chemical vapor deposition, Polarization, Fiber couplers, Scattering, Integrated optics

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Proceedings Article | 13 December 2000 Paper

Evaluation of irradiation-induced deep levels in Si

Kenichiro Kono, Jessica Sandland, Kazumi Wada, Lionel Kimerling

Proceedings Volume 4140, (2000) https://doi.org/10.1117/12.409120

KEYWORDS: Annealing, Charge-coupled devices, Electrons, Silicon, Radiation effects, Carbon, X-rays, Bismuth, Photovoltaics, Chemical species

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Proceedings Article | 15 March 2000 Paper

Ge-on-Si high-responsivity near-infrared photodetectors

Gianlorenzo Masini, Lorenzo Colace, Gaetano Assanto, Hsin-Chiao Luan, Kazumi Wada, Lionel Kimerling

Proceedings Volume 3953, (2000) https://doi.org/10.1117/12.379609

KEYWORDS: Germanium, Silicon, Photodetectors, Annealing, Heterojunctions, Near infrared, Optoelectronic devices, Heteroepitaxy, Semiconducting wafers, Electronic components

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Proceedings Article | 12 November 1999 Paper

Comparison of optical properties in GaN and InGaN quantum well structures

Shigefusa Chichibu, Amane Shikanai, Takahiro Deguchi, Akiko Setoguchi, Rikuro Nakai, Kazumi Wada, Steven DenBaars, Takayuki Sota, Takashi Mukai, Shuji Nakamura

Proceedings Volume 3896, (1999) https://doi.org/10.1117/12.370352

KEYWORDS: Quantum wells, Indium gallium nitride, Excitons, Gallium nitride, Absorption, Electroluminescence, Light emitting diodes, Electronics, Luminescence, Absorbance

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