| 1. |
- Svedin, Jan, et al.
(författare)
-
Development of a 210 GHz near-field measurement radar system based on an antenna-integrated MMIC receiver front-end and an ultra-compact HBV transmitter source module
- 2008
-
Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. - 9780819473493 ; 7117, s. Art. no. 71170H-
-
Konferensbidrag (refereegranskat)abstract
- The development of a 210 GHz radar system intended to study security applications such as personnel scanning is reported. The system is designed to operate with a transmit antenna floodlighting the target scene and a mechanically scanned antenna-integrated receiver module. For increased performance and potential future volume production the receiver front-end is based on highly integrated MMICs manufactured using the IAF 0.1 µm GaAs mHEMT process made available through a Swedish-German MoU. A single-chip MMIC solution is being developed containing feed antenna, LNA, mixer and an LO multiplier-chain. The transmitter part is based on a high-power HBV quintupler source-module.
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| 2. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
Development and Design of a 340 GHz Photomixer Source
- 2007
-
Ingår i: 18th International Symposium on Space THz Technology – ISSTT 2007.
-
Konferensbidrag (refereegranskat)abstract
- We present the design of an InGaAlAs/InP uni-traveling-carrier photo-diode (UTC-PD) at mm-wave frequencies up to 340 GHz. The photo diode epitaxy is optimized using a quasi-3D software implementing the hydrodynamic semiconductor equations, for which an output power of 3 mW at 340 GHz was simulated. An equivalent circuit of the UTC-PD has been fitted to experimental S11 measurements up to 67 GHz. Finally, an optimized antenna coupled UTC-PD with choke filter has been designed. This MMIC circuit is intended for photomixing, with output power at 340 GHz.
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| 3. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
High Power Photonic MW/THz Generation Using UTC-PD
- 2008
-
Ingår i: GigaHertz SympoSium 2008. ; , s. 45-
-
Konferensbidrag (refereegranskat)abstract
- The ongoing research work concentrates on extending the previously accomplished UTC-PD fabrication and modelling techniques to 340 GHz and above. We have fabricated and characterized UTC-PDs intended for high power MW/THz generation. Several integrated antenna-detector circuits have been designed and characterised.
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| 4. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
UTC-PD Integration for Submillimetre-wave Generation
- 2008
-
Ingår i: 19th International Symposium on Space Terahertz Technology, ISSTT 2008; Groningen; Netherlands; 28 April 2008 through 30 April 2008. ; , s. P7-1, 135
-
Konferensbidrag (refereegranskat)abstract
- Because of the inherent difficulty to generate power in the frequency range 0.l-10 THz, the term 'THzgap' has been coined. Among a number of MW/THz generation techniques, the photomixer based sources hold high potential offering wide tunability and decent amounts of output power. The photomixing technique relies on the nonlinear mixing of two closely spaced laser wavelengths generating a beat oscillation at the difference frequency. In recent years, there has been an increasing interest in the Uni-Travelling-Carrier PhotoDiode (UTCPD) [1] for photomixing, photo receivers, MW/THz-wave generation, fibre-optic communication systems, and wireless communications. UTC-PDs have become very promising by demonstrating output powers of 20 mW at 100 GHz [1] and 25 μW at 0.9 THz [2].
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| 5. |
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| 6. |
|
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| 7. |
- Vukusic, Josip, 1972, et al.
(författare)
-
Development of Uni-Travelling-Carrier Photodiodes
- 2006
-
Ingår i: 4th ESA Workshop on Millimetre Wave Technology and Applications.
-
Konferensbidrag (refereegranskat)abstract
- We have fabricated and characterized InGaAsP/InP uni-travelling-carrier photodiodes (UTC-PDs). An UTC-PD layer structure in the material system InGaAlAs/InP was also designed and grown with in-house molecular beam epitaxy (MBE). Using standard III-V processing involving lithography, metallization and etching, diodes of different sizes have been fabricated. Time domain and eye-diagram measurements have been performed. Limitations in the measurement system were identified and compensated for when measuring the bandwidth. The resulting bandwidth is in agreement with the area dependent RC-limitation which was estimated using quasi-DC capacitance-voltage (C-V) measurements.
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| 8. |
- Vukusic, Josip, 1972, et al.
(författare)
-
Fabrication and Characterization of InGaAlAs/InP based Uni-Traveling-Carrier Photodiodes
- 2006
-
Ingår i: The Joint 31st International Conference on Infrared and Millimeter Waves and 14th International Conference on Terahertz Electronics. - 1424404002 ; , s. 138-
-
Konferensbidrag (refereegranskat)abstract
- We have fabricated and characterized InGaAlAs/InP uni-traveling-carrier photodiodes intended for photo-mixing and data-com applications. Bandwidths up to 60GHz were recorded with 8.5µm diameter devices for which a matched, integrated antenna-detector circuit has been designed.
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| 9. |
-
Abstract Book of the 30th Workshop on Compound Semiconductor Devices and Integrated Circuits in Europe
- 2006
-
Samlingsverk (redaktörskap) (refereegranskat)abstract
- The organisers and hosts warmly welcome you to the 30th Workshop on Compound Semiconductor Devices and Integrated Circuits in Europe, WOCSDICE 2006, at the Gullmarsstrand Hotel & Conferences in Fiskebäckskil, Sweden, May 14-17, 2006. The symposium is organised by the Chalmers Department of Microtechnology and Nanoscience (MC2) with the aim to create a forum where researchers can discuss latest results and trends in the field of compound semiconductor technology and related science. Established in 1973, WOCSDICE has a long-standing tradition. This workshop brings together both internationally recognised researchers and promising young scientists and engineers to disseminate state-of-the-art research findings in the areas of compound semiconductor materials, associated devices and integrated circuits. This year we have 56 papers (8 invited) divided into nine sessions and more than 78 delegates from 20 countries.Fiskebäckskil is a small restful community situated by Gullmarsfjorden opposite to the village Lysekil. Gullmarsfjorden is Sweden's only true threshold fjord, 25 km deep and 1 to 3 km broad. In the 19th century the small fishing village was transformed into a shipping society. The special wood based architecture of this time is well preserved until today. During the 20th century Fiskebäckskil, surrounded by red granite and the salty sea became a prime choice for summer recreation and swimming. The conference hotel (Gullmarsstrand) building is reverentially renovated and modernised to fulfil the highest expectations for a successful workshop.The workshop is sponsored by the Swedish Research Council (VR), the IEEE Sweden Section, the Swedish Foundation for Strategic Research (SSF-HSEP), Swedish Governmental Agency for Innovation Systems (VINNOVA), OXFORD Plasma Technology and Agilent technologies. We would like to thank these organisations for their support. We would also like to thank everyone who helped to arrange WOCSDICE 2006: the international steering committee for advice; the local organising committee; Eva Hellberg and Peter Jönsson for all WEB support; Catharina Forssén, and Ingrid Collin for help with registrations and payments; the session chairs; and everyone who attends or contributes with a presentation.On behalf of the local organisation committee, we would like to welcome all of you and wish you a pleasant and fruitful stay in Fiskebäckskil.Welcome!Jan Stake and Jan GrahnWOCSDICE2006 Chairmen
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| 10. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
A novel catadioptric dielectric lens for microwave and terahertz applications
- 2008
-
Ingår i: Microwave and Optical Technology Letters. - : Wiley. - 1098-2760 .- 0895-2477. ; 50:2, s. 416-419
-
Tidskriftsartikel (refereegranskat)abstract
- A novel dielectric catadioptric lens, suitable for near-field sensing and imaging, is presented. The focusing property and the far-field pattern of the lens are investigated using a 3D full-wave electromagnetic solver. Furthermore, the proposed catadioptric lens has been designed and fabricated from Delrin. Simulations and measurements of the far-field at 5 GHz and return loss versus frequency using a Bow-tie slot feeding antenna are presented.
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| 11. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
Catadioptric Dielectric Lens for Imaging Applications
- 2008
-
Ingår i: Proceedings of 33rd International Conference on Infrared, Millimeter, and Terahertz Waves. - 9781424421190 ; , s. 1 - 2
-
Konferensbidrag (refereegranskat)abstract
- The design and characterization results of a novel catadioptric dielectric lens are presented. Although being electrically small, the lens provides a focus in the close vicinity which makes it suitable to be used in microwave and terahertz systems. Several lenses of different dielectric materials and dimensions have been fabricated. A simple backscattering measurement method has been implemented in order to determine the focusing property of the lens.
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| 12. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
Design of Antenna Integrated Photomixers and Catadioptric Lenses for Emerging THz Applications
- 2008
-
Ingår i: 2008 ANSYS Regional Conference.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- We will present design and modeling of antenna integrated photomixers for terahertz generation. In addition, the design and the quasioptical integration a novel catadioptric dielectric lens, suitable for imaging applications, will be presented. Although having a tremendous potential, the terahertz (0.1 – 10 THz) regime in the frequency spectrum and its applications are hindered due to the lack of viable and high power terahertz sources. This has led to the term “terahertz gap” being coined. We aim to construct compact sources utilizing the lens-coupled antenna-integrated photomixer sources based on Uni-Travelling-Carrier Photomixers (UTC-PD). These sources are one of the key components which could significantly bridge the terahertz gap.However, optimization of the epitaxial layer structure of the UTC-PD is necessary for high-power THz generation. The epilayers of the UTC-PD is designed and optimized in TCAD. Antennas are designed using HFSS while the impedance of the antenna at a specific bandwidth from HFSS is used to optimize the UTC-PD epilayers and vice versa. Thus proper impedance match and therefore high power THz generation is possible.A novel catadioptric dielectric lens is designed and characterized using HFSS. The lens provides an alternative solution to be used as a focusing element and therefore suitable for imaging or similar applications.In fine, we aim to combine the photomixer source and the lens in order to attain compact but powerful THz sources.
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| 13. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
Microwave S-parameter Characterization of an Antenna-Coupled Catadioptric Lens
- 2009
-
Ingår i: IEEE Antennas and Wireless Propagation Letters. - 1548-5757 .- 1536-1225. ; 8, s. 1299-1301
-
Tidskriftsartikel (refereegranskat)abstract
- The focusing property of a bow-tie antenna coupled catadioptric lens is studied experimentally using a vector measurement setup. The results show that the lens-antenna provides short-range focusing. Furthermore, the return loss of the lens-antenna was determined numerically and confirmed experimentally from 1 GHz to 10 GHz. The lens-antenna provides 60% bandwidth (VSWR ≤ 2) centered at 6 GHz. Finally, the lens-antenna was employed to detect and locate buried objects and results are presented.
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| 14. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
Millimeter Wave Characterization of a Catadioptric Lens for Imaging Applications
- 2009
-
Ingår i: IEEE Microwave and Wireless Components Letters. - 1558-1764 .- 1531-1309. ; 19:11, s. 680-682
-
Tidskriftsartikel (refereegranskat)abstract
- Characterization of a catadioptric dielectric lens-horn configuration for short-range sensing and imaging is presented. The focusing property is investigated both numerically and experimentally at 108 GHz. The lens-horn provides a focal spot of ~ 0.9λ at a distance of ~ 4.5λ. An imaging example employing the lens in a CW imaging setup is presented. A test pattern was imaged and a marked improvement in image resolution was observed. With the aid of the lens, features close to the wavelength are resolved, which are absent or indistinguishable otherwise.
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| 15. |
- Banik, Biddut Kumar, 1978, et al.
(författare)
-
Optimization of the UTC-PD Epitaxy for Photomixing at 340 GHz
- 2008
-
Ingår i: International Journal of Infrared and Millimeter Waves. - : Springer Science and Business Media LLC. - 0195-9271 .- 1572-9559. ; 29:10, s. 914-923
-
Tidskriftsartikel (refereegranskat)abstract
- We present a method to optimize the epitaxial layer structure of an InGaAs/InP uni-traveling-carrier photo-diode (UTC-PD) for continuous THz-wave generation. The design approach used is general in that it can be applied for any target frequency while this study focuses on 340 GHz. The photodiode epitaxy is modeled and optimized using a TCAD software implementing the hydrodynamic semiconductor equations. This physical device model was found to be in good agreement with reported experimental results. It is shown that the UTC-PD can generate ~1 mW at 340 GHz by choosing the optimum absorption layer and collection layer thicknesses.
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| 16. |
- Bryllert, Tomas, et al.
(författare)
-
11% efficiency 100 GHz InP-based heterostructure barrier varactor quintupler
- 2005
-
Ingår i: Electronics Letters. - : Institution of Engineering and Technology (IET). - 0013-5194 .- 1350-911X. ; 41:3, s. 131-132
-
Tidskriftsartikel (refereegranskat)abstract
- A record conversion efficiency of 11.4% at 100 GHz using a heterostructure barrier varactor (HBV) quintupler is demonstrated. The quintupler is based on a microstrip circuit mounted in a full-height crossed-waveguide block. The nonlinear element consists of a planar HBV diode fabricated in InGaAs=InAlAs=AlAs epitaxial layers on an InP substrate.
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| 17. |
- Bryllert, Tomas, 1974, et al.
(författare)
-
A High-Power Frequency Tripler for 100 GHz
- 2006
-
Ingår i: The Joint 31st International Conference on Infrared and Millimeter Waves and 14th International Conference on Terahertz Electronics. - 1424404002 ; , s. 30-
-
Konferensbidrag (refereegranskat)abstract
- We present a Heterostructure Barrier Varactor (HBV) based tripler for power generation at ~100 GHz. The matching circuit for the HBV diode is implemented in microstrip on an AlN substrate with the diode flip-chip soldered. The microstrip circuit is mounted in a waveguide configuration. To simplify the fabrication and assembly no DC ground is used and the waveguides are full-height. 130 mW of output power at 114 GHz is achieved without the use of any tuners.
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| 18. |
|
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| 19. |
- Bryllert, Tomas, 1974, et al.
(författare)
-
High Power HBV Multipliers
- 2007
-
Ingår i: 18th International Symposium on Space THz Technology.
-
Konferensbidrag (refereegranskat)abstract
- We present a high-power frequency tripler for 100 GHz. The tripler - that is based on a single HBV diode - produces >200 mW of output power with a 3-dB bandwidth of 6%. This is the highest output power ever recorded for an HBV based multiplier irrespective of output frequency. The module features an ultra-compact waveguide block design and a microstrip matching circuit on high-thermal-conductivity AlN to improve the power handling capability.
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| 20. |
- Emadi, Arezoo, 1977, et al.
(författare)
-
Design, Fabrication and characterisation of High Power HBV Diodes
- 2005
-
Ingår i: 16th International Symposium on Space Terahertz Technology; Chalmers Conference Centre, May 2-4, 2005, Gothenburg, Sweden, (Eds. Jan Stake, Harald Merkel.). ; , s. Session: P05-04
-
Konferensbidrag (refereegranskat)abstract
- We present design and analysis of material structures and device geometries for heterostructure barrier varactor diodes (HBVs) for high-power frequency multipliers. The methods aim at finding optimum epitaxial layer structures with respect to diode power handling capability and efficiency. A distributed device geometry for further increasing the output power levels whilst maintaining acceptable device temperatures is also presented. Finally, an electro-thermal HBV model with the ability of incorporating temperature-dependent device parameters is used to simulate the introduced devices, followed by a design example of a 3×4-barrier high-power HBV diode.
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| 21. |
- Emadi, Arezoo, 1977, et al.
(författare)
-
Optimum Barrier Thickness Study for the Heterostructure Barrier Varactror Diode
- 2006
-
Ingår i: WOCSDICE 2006. - 1652-0769. ; , s. 55-57
-
Konferensbidrag (refereegranskat)abstract
- This experimental study aims at finding the optimum barrier thickness in heterostructure barrier varactor (HBV) diodes, to improve the diode efficiency especially for high-power frequency multiplier applications. The influence of barrier thickness on the conduction current is investigated for different biases and device temperatures. We found that for an InP-based HBV, there is an optimum barrier thickness range between 10 to 14 nm which causes the lowest possible leakage current.
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| 22. |
- Emadi, Arezoo, 1977, et al.
(författare)
-
Optimum barrier thickness study for the InGaAs/InAlAs/AlAs heterostructure barrier varactor diodes
- 2007
-
Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 90:1, s. 012108-3
-
Tidskriftsartikel (refereegranskat)abstract
- This experimental study aims at finding the optimum barrier thickness in heterostructure barrier varactor (HBV) diodes to improve the diode efficiency especially for high-power frequency multiplier applications. The influence of barrier thickness on the destructive current leaking over and through the barrier is investigated for different biases and operating temperatures. The authors found that for an InP-based HBV, there is an optimum barrier thickness range between 10 to 14 nm which causes the lowest possible leakage current.
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| 23. |
- Habibpour, Omid, 1979, et al.
(författare)
-
Characterisation of Exfoliated Graphene
- 2009
-
Ingår i: WOCSDICE 2009.
-
Konferensbidrag (refereegranskat)abstract
- High-frequency devices based on graphene is a promising field of research. In this paper we investigate two important parameters which based on theory are essential in order to have nonlinear responses in graphene. The first parameter is scattering time which should be as high as 1ps. Also the electrical field of the incident radiation should be higher a certain threshold in order to have nonlinear response. This threshold is generally quite high and increases with frequency and carrier density, so it is essential that graphene flake tolerate high electrical field. The first condition cannot be reached by graphene on SiO2/Si substrate according to ourinvestigation.
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| 24. |
- Ingvarson, Mattias, 1974, et al.
(författare)
-
An electro-thermal HBV model
- 2005
-
Ingår i: IMS 2005. ; , s. 1151-1153
-
Konferensbidrag (refereegranskat)
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| 25. |
-
International Symposium on Space Terahertz Technology
- 2006
-
Samlingsverk (redaktörskap) (refereegranskat)abstract
- The 16th International Symposium on Space Terahertz Technology was held at Chalmers, Göteborg, Sweden on May 2-4, 2005. This was the fi rst time the ISSTT meeting was held outside the US. More than 150 delegates from Europe, US and Asia attended and 147 scientifi c papers were presented. The meeting was organised by research groups at the microwave electronics laboratory, MC2, and GARD, Onsala space observatory. The programme was divided into 11 oral sessions with 63 papers (5 invited) and one poster session with 83 papers. Latest result on terahertz technologies for space applications were presented such as sensitive superconducting electronics (HEB/SIS), detectors, sources and systems. New applications of terahertz technology, e.g. for biotechnology, were also presented by Peter Siegel, Caltech (invited talk). Furthermore, we offered lab tours through MC2, conference dinner at Elfsborgs Fästning and fi nally a trip to Onsala space observatory. The symposium was sponsored by the Swedish Research Council (VR), IEEE Sweden Section, Swedish Space Corporation, Ericsson AB, COMSOL AB and our exhibitors: Omnisys Instruments AB, SAAB Ericsson Space AB, and European Southern Observatory (ESO). I would like to thank these organisations for their support. I would also like to thank everyone who helped to make the Symposium a success: international steering committee for advice and for reviewing abstracts; local organising committee; Eva Hellberg and Peter Jönsson for WEB support; Monica Hansen-Torvaldsson, Catharina Forssén, and Ingrid Collin for help with registrations and payments; Chalmers president Jan-Eric Sundgren and Erik Kollberg for opening the meeting; staff at Chalmers Conference Center; the session chairmen; and everyone who attended or contributed a presentation. Also an additional thanks to Mattias Ingvarson for putting this proceeding together.
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| 26. |
-
International Symposium on Terahertz Science and Technology between Japan and Sweden
- 2009
-
Samlingsverk (redaktörskap) (refereegranskat)abstract
- The organisers and hosts warmly welcome you to the second International Symposium on Terahertz Science and Technology between Japan and Sweden, at Chalmers University of Technology, Göteborg, on November 18-20, 2009. The symposium is organised by the Department of Microtechnology and Nanoscience (MC2) at Chalmers. The aim is to create a forum and platform where researchers from the two countries can discuss latest results and trends in the field of terahertz science and technology. This year we have two keynote and 19 invited lectures divided into nine sessions.Sandwiched between the optical on the short wavelength side and radio on the long wavelength extreme, the terahertz (THz) or far-infrared has long been considered the last remaining scientific gap in the electromagnetic spectrum. The broad spectrum of THz applications has attracted researchers from different disciplines dealing with optics and photonics, microwave engineering and semiconductor physics. The role of this meeting is not only bridging the THz-gap but also strengthening the collaboration between Japan and Sweden.Chalmers is a university of technology in which research and teaching are conducted on a broad front within technology, natural science and architecture. Chalmers was founded in 1829. The university is named after the major benefactor, William Chalmers, one of the directors of the successful Swedish East India Company in Göteborg. Chalmers became an independent foundation in 1994. The meeting will be held at William Chalmers private residence, Chalmerska huset, which was erected in 1805-1807 and designed in a neoclassical style.The workshop is sponsored by the Swedish Research Council (VR) and MC2, Chalmers. We would like to thank these organisations for their support. We would also like to thank everyone who helped to arrange Japan-Sweden Terahertz Symposium (JSTS) 2009: the international steering committee for advice; the local organising committee: Eva Hellberg, Aleksandra Malko, Aik-Yean Tang, Dr. Sergey Cherednichenko, Dr. Biddut Banik and Prof. Dag Winkler for all practical efforts; Eriko Naito and Prof. Anders Karlsson at the Embassy of Sweden in Tokyo; our host Anna Bergius Hartman during the stay in Chalmerska huset; Dr. Göran Alestig for arranging the lab tour; invited speakers and everyone who attends or contributes to this event.On behalf of the local organising committee, we would like to welcome you all and wish you a pleasant and fruitful stay in Göteborg.Welcome!Jan Stake JSTS 2009 Chairman
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| 27. |
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| 28. |
- Nygren, Stefan, et al.
(författare)
-
µFab: The Swedish Micro- and Nanofabrication Network
- 2006
-
Ingår i: Micro Structure Workshop. ; , s. 65-
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Sweden holds a very strong position in microstructure technology (MST). During the last decades universities, research institutes and commercial enterprises have all contributed to cover the entire field from academic research to industrial production. A key factor in this development has been, and still is, the availability of state-of-the-art process facilities, with the three large cleanrooms at Chalmers, KTH and Uppsala University at the top-of-the-line. These laboratories have now entered into a collaborative network, µFab or the Swedish Micro- and Nanofabrication Network, an open user facility and an excellent resource for education, research and industrial development. More than 50 % of the technical presentations at this workshop (MSW 2006) is based on laboratory work within the µFab network.
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| 29. |
- Olsen, Arne, 1974, et al.
(författare)
-
Compact frequency sources using high-order multipliers
- 2009
-
Ingår i: 5th ESA Workshop on Millimetre Wave Technology and Applications. ; , s. 189-193
-
Konferensbidrag (refereegranskat)abstract
- High-order multipliers are a suitable method for making compact frequency sources for high frequencies (> 100 GHz). A fixed frequency phased-locked source, where a fundamental source is multiplied up using among an in-house varactor diode multiplier, has a low phase noise and will be described in this article. These multipliers are based on the Heterostructure Barrier Varactor (HBV) diode, and can either triple or quintuple the frequency. Fixed frequencies from 90 to 220 GHz can be produced by using a combination of only one diode multiplier and a common source unit. A design rule for next generation of multipliers, where the power handling is emphasised, is also included. These multipliers will take the signal source up to a frequency of 500 GHz.
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| 30. |
- Olsen, Arne, 1974, et al.
(författare)
-
HBV Frequency Quintuplers
- 2005
-
Ingår i: 16th International Symposium on Space Terahertz Technology.
-
Konferensbidrag (refereegranskat)abstract
- A 500 GHz heterostructure-barrier-varactor quintupler has been designed and fabricated. The design consists of a mixture of waveguide and microstrip components for impedance matching. A InP based HBV diode is flip-chip mounted onto the quartz circuit, where beam-leads are used for ground connections to the waveguide block. Extensive back-side processing has been carried out in order to create these beam-leads. The multiplier is a frequency scaled version of a successful 100 GHz quintupler with a conversion efficiency of 11.4%.
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| 31. |
- Rahman, Syed, 1981, et al.
(författare)
-
Hydrodynamic Simulations of Unitraveling-Carrier Photodiodes
- 2007
-
Ingår i: IEEE Journal of Quantum Electronics. - 0018-9197 .- 1558-1713. ; 43:11, s. 1088-1094
-
Tidskriftsartikel (refereegranskat)abstract
- We present simulated results of a unitraveling-carrier photodiode (UTC-PD) using the hydrodynamic carrier transportation model. A maximum responsivity of 0.25 A/W and a small-signal 3-dB bandwidth of 52 GHz were obtained for a 220-nm-thick InGaAs absorption layer. The physical properties of the UTC-PD have been investigated at different optical injection levels. Modulation of the energy-band profile due to the space charge effect has been observed at high injection level, and an electron velocity overshoot of 3e7 cm/s has been found to effectively delay the onset of space charge effects. Comparisons with reported simulated results using the drift–diffusion model as well as reported experimental results are presented. The results suggest the necessity of using the hydrodynamic transport equations to accurately model the UTC-PD. In addition, it has been corroborated that the photoresponse of the UTC-PD could be improved by incorporating a graded doping profile in the absorption layer.
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| 32. |
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| 33. |
- Sobis, Peter, 1978, et al.
(författare)
-
A 110 GHz GaAs Schottky Diode Mixer on Quartz with planar LO feed
- 2005
-
Ingår i: Gigahertz, Uppsala Sweden, November 8-9 2005.
-
Konferensbidrag (refereegranskat)abstract
- A fixed-tuned 110 GHz subharmonically pumped GaAs schottky diodemixer design with planar LO feeding is presented. The designconsists of a shielded microstrip circuit on a 5 mil thick quartzsubstrate, mounted in a full height WR-08 RF waveguide split blockdesign. The UMS DBES105a diode series pair is used as a non-linearmixing element and substrate vias are used for the IF/DC groundreturn. The planar microstrip circuitry, waveguide interface anddiode chip have been modeled and simulated in HFSS. Simulatedresults are showing a conversion loss of 10 dB, with less than 7dBm LO power, with RF and LO bandwidths of more than 10%.Simulations will be verified with experimental results.
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| 34. |
- Sobis, Peter, 1978, et al.
(författare)
-
A 170 GHz 45 degree Hybrid for Submillimeter Wave Sideband Separating Subharmonic Mixers
- 2008
-
Ingår i: IEEE Microwave and Wireless Components Letters. - 1558-1764 .- 1531-1309. ; 18:10, s. 680-682
-
Tidskriftsartikel (refereegranskat)abstract
- We present a 135/45 degree phase shifter hybrid intended to be used in subharmonic sideband separation mixer schemes at submillimeter-wave frequencies. The design consists of an increased height 90 degree 6-arm branch guide coupler with a three stub loaded differential line 45 degree phase shifter at the output. The device has been implemented at G-band in an E-plane WR-05 splitblock design with a center frequency of 170 GHz and 15% bandwidth. Measured S-parameter are in good agreement with simulations showing an isolation and return loss better than 20 dB and an amplitude and phase imbalance within 0.4 dB and 2 degree, respectively.
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| 35. |
- Sobis, Peter, 1978, et al.
(författare)
-
Compact 340 GHz Receiver Front-Ends
- 2009
-
Ingår i: 20th International Symposium on Space Terahertz Technology. ; , s. 183-189
-
Konferensbidrag (refereegranskat)abstract
- A compact 340 GHz room temperature receiver front-end has been developed consisting of a subharmonic Schottky diode mixer module with an integrated LNA. A novel sideband separation topology has been evaluated by using a pair of the developed mixers interconnected by external waveguide branch guide coupler hybrids for the LO and RF feedings and coaxial IF hybrids, measuring sideband suppression levels of 5 dB to 15 dB over the 315-365 GHz band.For efficient LO pumping of the sideband separating mixer, a novel high power LO chain based on a 5 x 34 GHz HBV quintupler (170 GHz LO source) has been developed with an ultra compact mechanical block housing, not much larger then a waveguide flange. We have also looked into a broadband medium LO power source consisting of a W-band active multiplier module, based on commercial MMIC chips from Hittite, followed by a medium power Schottky doubler from VDI.The demonstrated compact receiver front end has a considerably reduced size and weight owing to the high multiplication factor of the compact LO chain and mixer with integrated LNA. The novel sideband separating topology that uses 90 degree hybrids for both LO and RF resolves the standing wave issue of a previously proposed topology, in which a matched Y-junction was used as an RF hybrid and a branch guide coupler with a 45 degree differential line phase shifter at the output, was used for the LO feeding. The proposed topology improves both the sideband suppression and reduces the standing waves at the LO and RF ports.
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| 36. |
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| 37. |
- Sobis, Peter, 1978, et al.
(författare)
-
Design of a Subharmonic 340 GHz GaAs Schottky Diode Mixer on Qaurtz with Integrated Planar LO-IF Duplexer
- 2006
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Ingår i: 4th ESA Workshop on Millimetre Wave Technology and Applications.
-
Konferensbidrag (refereegranskat)abstract
- A fixed tuned 340 GHz sub-harmonically pumped GaAs schottky diode mixer design is presented. The design consists of a 50 µm thick quartz microstrip circuit mounted in a full height waveguide splitblock and uses a flip-chip mounted VDI SC1T2-D20 anti-parallel diode pair. The RF and LO waveguide to microstrip transitions are located at each end of the substrate and a planar LO-IF duplex filter has been integrated with the mixer circuitry, providing for the possibility of planar LO feeding in the future. A comparison of the coaxial with the lumped port method for EM modeling of the diode is presented, showing good agreement between the two methods. The diode parameters and IV characteristics have been matched with a standard diode model used in the harmonic balance analysis of the complete mixer circuit. Preliminary test results from a conceptually scaled 110 GHz mixer design using the UMS DBES105a schottky diode chip are presented showing a conversion loss of 10.8 dB with 3 dBm of LO power.
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| 38. |
- Sobis, Peter, 1978, et al.
(författare)
-
Development of a Compact 340 GHz Receiver Front-End
- 2009
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Ingår i: 5th ESA Workshop on Millimetre Wave Technology and Applications. ; :WPP-300, s. 123-130
-
Konferensbidrag (refereegranskat)abstract
- A compact 340 GHz roomtemperature receiver front-end module has been developed consisting of a subharmonic Schottky diode mixer module with an integrated LNA. A novel sideband separation topology has been evaluated by using a pair of the developed mixers interconnected by external waveguide branch guide coupler hybrids for the LO and RF feedings and coaxial IF hybrids, measuring sideband suppression levels of 5dB to 15dB over the 315-365 GHz band.For efficient LO pumping of the image rejection mixer, a novel high power LO chain based on a 5 x 34 GHz HBV quintupler (170 GHz LO source) has been developed with an ultra compact mechanical block housing, not much larger then a waveguide flange. The HBV LO source has been compared to a broadband medium power source consisting of a W-band active multiplier module, based on commercial MMIC chips from Hittite, followed by a medium power Schottky doubler from VDI.The demonstrated compact receiver front-end has considerably reduced size and weight owing to the high multiplication factor of the compact LO chain and mixer integrated LNA. The novel image rejection topology resolves the standing wave issue of a previously proposed topology, improving both the image rejection response and reducing the standing waves at the LO and RF ports.
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| 39. |
- Sobis, Peter, 1978, et al.
(författare)
-
Optimisation and Design of a Suspended Subharmonic 340 GHz Schottky Diode Mixer
- 2006
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Ingår i: The Joint 31st International Conference on Infrared and Millimeter Waves and 14th International Conference on Terahertz Electronics. - 1424404002 ; , s. 193-
-
Konferensbidrag (refereegranskat)abstract
- A fixed tuned subharmonic 340 GHz GaAs Schottky diode mixer design is presented. The mixer consists of a 3 mil quartz substrate that is suspended in a LO and RF reduced height waveguide splitblock, and uses a coaxial connector for the IF interface. It has been designed for the VDI SC1T2-D20 antiparallell diode chip that is flip-chip mounted on the circuit. The performance of three types of RF stop filter topologies have been evaluated and will be presented.
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| 40. |
- Sobis, Peter, 1978, et al.
(författare)
-
Towards a THz Sideband Separating Subharmonic Schottky Mixer
- 2008
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Ingår i: 19th International Symposium on Space Terahertz Technology, ISSTT 2008; Groningen; Netherlands; 28 April 2008 through 30 April 2008. ; , s. 483-
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Konferensbidrag (refereegranskat)abstract
- Today GaAs Schottky mixers with state of the art planar submicron diodes are used for THz-detection up to 3 THz. GaAs Schottky diodes can operate in room temperature which makes them good candidates for space applications and an interesting low cost alternative to low noise cryogenic SIS and HEB technologies.To our knowledge this is the first time a sideband separation mixer using subharmonic Schottky mixers is presented. In this poster we present the current status of the development of a novel sideband separating subharmonic receiver topology operating at 340 GHz. The design of a subharmonic mixer and the LO and RF waveguide hybrids is presented followed by an account of measured S-parameters and mixer noise temperature and some initial SSB mixer measurements.
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| 41. |
- Sobis, Peter, 1978, et al.
(författare)
-
Towards a THz Sideband Separating Subharmonic Schottky Mixer
- 2008
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Ingår i: GigaHertz SympoSium 2008, p. 46.
-
Konferensbidrag (refereegranskat)abstract
- GaAs Schottky mixers with state of the art planar submicron diodes are used for THz-detection up to 3 THz today [1]. GaAs Schottky diodes can operate in room temperature which makes them good candidates for space applications and an interesting low cost alternative to low noise cryogenic SIS and HEB technologies. The main advantage of a sideband separation scheme besides that the lower and upper sidebands are indeed separated, is that the IF bandwidth is increased by a factor of two. Moreover, there is no need for image rejection filters on the RF input, which can be bulky and increase the weight and cost of the overall receiver system. Sideband separation mixers have been implemented at THz frequencies before [2], however up to this point they have never been tried with Schottky diodes in a subharmonic mixer configuration. We will present the current status of the development of a novel sideband separating subharmonic reciever topology operating at 340 GHz, see Fig1. The design of a subharmonic mixer and the LO and RF waveguide hybrids will be presented followed by an account of measured results of the individual components.
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| 42. |
- Stake, Jan, 1971, et al.
(författare)
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Development of high power HBV multipliers for millimeter wave applications
- 2007
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 0277-786X .- 1996-756X. - 9780819468970 ; 6739, s. 67390U-
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Konferensbidrag (refereegranskat)abstract
- We present a high-power frequency tripler for 110 GHz and a quintupler for 200-210 GHz. The tripler (×3), that is based on a single HBV diode, produces 240 mW of output power with a 3-dB bandwidth of 6%. This is the highest output power ever recorded for an HBV based multiplier irrespective of output frequency. The module features an ultra-compact waveguide block design, and a microstrip matching circuit on high-thermal-conductivity AlN to improve the power handling capability. Furthermore, we present an HBV quintupler (×5) that delivers more than 20 mW at 202 GHz.
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| 43. |
- Stake, Jan, 1971
(författare)
-
HBV diode multipliers
- 2005
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Ingår i: GAAS 2005 Workshop.
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Konferensbidrag (refereegranskat)
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| 44. |
- Stake, Jan, 1971, et al.
(författare)
-
Heterostructure Barrier Varactor Quintuplers for Terahertz Applications
- 2008
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Ingår i: Proceedings of the 3rd European Microwave Integrated Circuit Conference. - 9782874870071 ; , s. 206-209
-
Konferensbidrag (refereegranskat)abstract
- We present progress and status of Heterostructure Barrier Varactor quintupler sources for 170 GHz and 210 GHz (G-band). The source modules feature an ultra-compact waveguide block design, and a microstrip matching circuit on high-thermal-conductivity AlN to improve the power handling capability. Furthermore, we present progress on design and fabrication of integrated HBV circuits for terahertz applications.
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| 45. |
- Stake, Jan, 1971, et al.
(författare)
-
High Efficiency HBV Multipliers
- 2006
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Ingår i: Proceedings of the 1st European Microwave Integrated Circuits Conference. ; , s. 39-42
-
Konferensbidrag (refereegranskat)
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| 46. |
- Stake, Jan, 1971, et al.
(författare)
-
High efficiency W-band HBV Tripler and Device Reliability Studies
- 2006
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Ingår i: 4th ESA Workshop on Millimetre Wave Technology and Applications.
-
Konferensbidrag (refereegranskat)abstract
- We report on the design and MBE-growth of heterostructure barrier varactor (HBV) diode materials. The quality and performance of in-house HBV materials are presented. Furthermore, temperature operating life tests of the HBV diodes indicate a maximum operating temperature of 180°C before onset of severe degradation. Finally, a state-of-the-art tripler efficiency of 21% for a W-band tripler has been demonstrated using planar 2x2-barrier HBV diodes (Chalmers MBE766).
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| 47. |
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| 48. |
- Stake, Jan, 1971, et al.
(författare)
-
Terahertz generation by multiplication
- 2007
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Ingår i: Terahertz Frequency Detection and Identification of Materials and Objects. - Dordrecht : Springer Netherlands. - 9781402065026 ; , s. 17-30
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- We report on the status of symmetric varactor diode multipliers for signal generation in the terahertz frequency range. The progress and basic principles of Heterostructure Barrier Varactor (HBV) diodes are presented. Furthermore, the design methodology and electro-thermal simulation results of high power HBV multipliers for signal generation in the millimeter and sub-millimeter wave region are also presented. Finally, a state-of-the-art HBV tripler with an output power of 0.2 Watt at 113 GHz is presented.
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| 49. |
- Stake, Jan, 1971
(författare)
-
Terahertz sources and detectors for security applications
- 2006
-
Ingår i: Safety and Security Systems in Europe.
-
Konferensbidrag (refereegranskat)abstract
- We will present recent results on terahertz source and detector technology, (0.1-10 THz), for safety and secu-rity applications. The development of terahertz technology remains very challenging. This is primarily because this frequency band lies in the transition between classical microwave electronics and photonics. For example, traditional transistor based monolithic integrated circuits does not work well above 150 GHz. Similarly, semiconductor lasers used in the IR (and visible) region does not work well below 2 THz and still need cooling at these long wavelengths (ca 100µm). Today, high power and compact multipliers are the most efficient solution for the frequency range 0.2-2THz (THz-gap). The Heterostructure Barrier Varactor (HBV) diode was invented 1989 at Chalmers and is used in high order frequency multiplier circuits (x3, x5). We have demonstrated significant output power in the millimeter wave region (0.2W @ 114GHz) and highly efficient HBV circuits up to 500GHz. Progress and development of high power HBV sources for the terahertz fre-quency range will be discussed and presented. Furthermore, research and development of direct and hetero-dyne detector technology, both Schottky diodes and Hot Electron Bolometers (HEB), for use in imaging (THz-camera) applications will be presented. These technologies are crucial for development of new THz-sensor systems.
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| 50. |
- Stake, Jan, 1971, et al.
(författare)
-
Terahertz technology and applications
- 2008
-
Ingår i: International Symposium on Terahertz between Japan and Sweden.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- THz or submillimetre-wave sensing covers the frequency range from 300 GHz to 10 THz (wavelengths from 1 mm to 30 µm). With energy levels in the 1.2-40 meV range, terahertz interactions with matter involve intermolecular, rather than atomic transitions. This gives rise to some imaging and spectroscopy applications that are unique to this particular region of the electromagnetic spectrum. Many polar molecules in the low pressure gaseous state have strong, narrow band, vibrational and rotational emission or absorption modes that peak in this regime and are used as probes for quantum chemistry, astrophysical processes and the dynamics of planetary atmospheres, including the Earth. Still, the terahertz spectral region is by far the least explored portion of the electromagnetic spectrum. A great obstacle has been the absence of robust and reasonable inexpensive receiver components that can operate at room temperature. The talk will consist of two parts: a) room temperature technology for THz applications and b) terahertz applications in biology and medicine.At Chalmers, several key technologies are explored for future THz systems such as radiometers, radars, spectrometers and communication links for frequencies from approximately 100GHz to several THz. Transistors with 50 nm gate length based on the two dimensional electron gas can at present be used for frequencies up to and above 300 GHz for circuits such as amplifiers, frequency mixers, frequency multipliers, oscillators, and modulators. For even higher frequencies, submicron low noise Schottky diodes are used for heterodyne mixers. We are currently pursuing studies of high functionality THz mixers (SSB) and in-house fabrication of monolithically integrated Schottky diode circuits. Results and progress on single side band mixers at 340 GHz aimed for future climate research satellites such as the ESA PREMIER mission. Furthermore, single chip receivers (MMIC) up to 220 GHz for imaging applications will be presented.THz imaging and spectroscopy for biomedical applications is being targeted for the very first time, including assessment of protein conformational states, molecular binding and interaction, DNA hybridization, isomer identification, skin hydration level, drug delivery, wound healing, tumour identification and margin assessment, and cell processes. The submillimeter wave advanced technology group at Caltech, in conjunction with the group at Chalmers (J.Stake was visiting Caltech under a sabbatical), set up a very flexible exposure and monitoring system to be used to systematically investigate the interaction of THz radiation with cells.The talk will cover the latest results obtained from Chalmers on MMICs and Schottky diode mixers for terahertz frequencies (sensors), as well as results from initial investigations towards thermal and non-thermal effects of THz radiation on biological systems (Caltech/JPL-Chalmers).
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