| 1. |
- Alderman, Byron, et al.
(författare)
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A New Pillar Geometry for Heterostructure Barrier Varactor Diodes
- 2001
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Ingår i: 12th International Symposium on Space Terahertz Technology. ; , s. 330-339
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Konferensbidrag (refereegranskat)abstract
- We report on a novel diode geometry, with reduced thermal resistance, for Heterostructure Barrier Varactor, HBV, diodes. The pillar geometry presented here involves the complete removal of the substrate, electrical contacted is made by the forward and reverse side processing of metallic pillars. We propose that there is a limit to the maximum number of barriers that can be used to increase the power capability of a HBV. An analytical model has been developed to study these effects. In considering the case of a perfect thermal heat sink the limit is found to be fourteen, in applying this model to the new pillar structure this is reduced to six.
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| 2. |
- Dillner, Lars, 1968, et al.
(författare)
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Frequency Multiplier Measurements on Heterostructure Barrier Varactors on a Copper Substrate
- 2000
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Ingår i: IEEE Electron Device Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 0741-3106 .- 1558-0563. ; 21:5, s. 206-208
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Tidskriftsartikel (refereegranskat)abstract
- We have fabricated heterostructure barrier varactors (HBV) on a copper substrate, which offers reduced spreading resistance, and improved thermal conductivity compared to an InP substrate. The devices are fabricated without degrading the electrical characteristics. The three-barrier HBV material grown by MOVPE has a leakage current of only 0.1 mu A/ mu m/sup 2/ at 19 V. The maximum capacitance is 0.54 fF/ mu m/sup 2/. In a frequency tripler experiment a maximum output power of 7.1 mW was generated at 221 GHz with a flange-to-flange efficiency of 7.9%.
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| 3. |
- Dillner, Lars, 1968, et al.
(författare)
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Heterostructure Barrier Varactor Multipliers
- 2000
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Ingår i: GAAS 2000. - 0862132223 ; 1, s. 197-200
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Konferensbidrag (refereegranskat)abstract
- The Heterostructure Barrier Varactor (HBV) diode and its application in frequency multipliers is reviewed. Different material systems and HBV models are described. Multiplier performance versus diode parameters and some practical multiplier designs are discussed as well. The best result until now is an efficiency of 12% and an output power of 9 mW at an output frequency of 250 GHz.
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| 4. |
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| 5. |
- Dillner, Lars, 1968, et al.
(författare)
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High Efficiency HBV Multipliers for Millimetre Wave Generation
- 2000
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Ingår i: the XIII International Conference on Microwaves, Radar and Wireless Communications. - 8390666235 ; 3, s. 47-54
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Konferensbidrag (refereegranskat)abstract
- We describe the heterostructure barrier varactor (HBV) diode and its application in frequency multipliers. Different material systems and HBV models are described. In a frequency tripler experiment a maximum output power of 7.1 mW was generated at 221 GHz with a flange-to-flange efficiency of 7.9%.
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| 6. |
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| 7. |
- Emadi, Arezoo, 1977, et al.
(författare)
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High power HBV multipliers for F- and G- band applications
- 2004
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Ingår i: IRMMW 2004/THz 2004 / M. Thumm, W. Wiesbeck. - 0780384903 ; , s. 319-320
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Konferensbidrag (refereegranskat)abstract
- Progress and realisation of applications in the 100-240 GHz region is inhibited by the lack of high-power sources. Therefore, in an effort to reach watts of output power, we have tailored devices, circuits, materials, and design and fabrication methods for improved thermal management and high overall conversion efficiencies.
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| 8. |
- Fu, Ying, 1964, et al.
(författare)
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Carrier conduction through the quantum barrier in a heterostructure barrier varactor Induced by an AC-Bias
- 2000
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Ingår i: Superlattices and Microstructures. ; 28:2, s. 135-141
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Tidskriftsartikel (refereegranskat)abstract
- By solving the time-dependent Schrodinger equation, we have studied the quantum transport of a wavepacket in a GaAs/A1GaAs heterostructure barrier varactor (HBV) diode induced by an ac bias. The current conduction of a wavepacket is complicated due to the superposition of many different stationary states. When the oscillating frequency of the external bias is relatively low, the motion of the wavepacket follows the electric field induced by the external bias. When the frequency is too high (over 1000 GHz for the GaAs/A1GaAs HBV structure under investigation), the wavepacket becomes effectively confined by the oscillating bias, and the conduction current is significantly reduced.
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| 9. |
- Gustavsson, Manda, 1976, et al.
(författare)
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Development of Ultrafast Photodiodes for Microwave Photonics
- 2001
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Ingår i: GigaHertz 2001.
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Konferensbidrag (refereegranskat)abstract
- Ultrafast photodiodes with high saturation current are under development. Current voltage characteristics and capacitance voltage characteristics will be presented. Estimated values of the RC-limited 3-dB bandwidth, as a function of area, will be discussed
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| 10. |
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| 11. |
- Hollung, Stein, 1970, et al.
(författare)
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A Distributed Heterostructure Barrier Varactor Frequency Tripler
- 2000
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Ingår i: IEEE Microwave and Guided Wave Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1051-8207. ; 10:1, s. 24-26
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Tidskriftsartikel (refereegranskat)abstract
- We present a broadband nonlinear transmission line (NLTL) frequency multiplier at F-band. The multiplier consists of a finline section periodically loaded with 15 heterostructure barrier varactor (HBV) diodes. Tapered slot antennas are used to couple the fundamental signal from a WR-22 rectangular waveguide to the distributed multiplier as well as radiate the output power into free space. The frequency tripler exhibits 10-dBm peak radiated power at 130.5 GHz with more than 10% 3-dB bandwidth and 7% conversion efficiency. The tripler can be used as an inexpensive broad-band solid-state source for millimeter-wave applications.
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| 12. |
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| 13. |
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| 14. |
- Ingvarson, Mattias, 1974, et al.
(författare)
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Design, analysis and modelling of heterostructure barrier varactors for sub-millimetre wave frequency quintuplers
- 2003
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Ingår i: GigaHertz 2003, Linköping Electronic Conference Proceedings. - 1650-3740.
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Konferensbidrag (refereegranskat)abstract
- We report on the design, modelling and analysis of heterostructure barrier varactor (HBV) frequency quintuplers with output frequencies in the sub-millimetre wave region. The HBV is a symmetric varactor, thus only odd harmonics are generated and no DC bias is required. By incorporating several barriers in the device, the HBV is also capable of handling higher power levels than conventional varactors. This makes the HBV superior to the conventional Schottky varactor for high order frequency multiplier circuits. We present analytical models, which can be used to calculate parameters such as optimum doping concentration, layer structure, device area and series resistance for HBVs, as well as to predict the performance with respect to conversion efficiencies and output power levels. These parameters are then further optimised by harmonic balance simulations in commercial microwave EDA tools, for which we have developed accurate device models. We investigate the influence of embedding impedance levels for optimum conversion efficiency by means of analytical expressions and harmonic balance simulations. Theoretical calculations predict a maximum diode conversion efficiency to 500 GHz for a planar, six-barrier InGaAs HBV of more than 30 %.
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| 15. |
- Ingvarson, Mattias, 1974, et al.
(författare)
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Design and analysis of 500 GHz heterostructure barrier varactor quintuplers
- 2003
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Ingår i: Proceedings of the 14th International Symposium on Space Terahertz Technology.
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Tidskriftsartikel (refereegranskat)abstract
- We report on the design and analysis of heterostructure barrier varactor (HBV) frequency quintuplers with an output frequency of 500 GHz. The HBV is a symmetric varactor, thus only odd harmonics are generated and no DC bias is required. By incorporating several barriers in the device, the HBV is also capable of handling higher power levels than conventional varactors. This makes the HBV superior to the traditional Schottky varactor for high order frequency multiplier circuits. We present analytical, temperature dependent models, which can be used to calculate parameters such as optimum doping concentration, layer structure, device area and series resistance for HBVs, as well as to predict the performance with respect to conversion efficiencies and output power levels. These parameters are then further optimised by harmonic balance simulations in commercial microwave EDA tools, for which we have developed accurate device models. We investigate the influence of embedding impedance levels for optimum conversion efficiency by means of analytical expressions and harmonic balance simulations. Theoretical calculations predict a maximum diode conversion efficiency for a planar, six-barrier InGaAs HBV of more than 30%, for an input power level of 19 dBm. A waveguide circuit realisation of a 500 GHz HBV quintupler is presented.
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| 16. |
- Ingvarson, Mattias, 1974, et al.
(författare)
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Design of Material Structures for Heterostructure Barrier Varactors
- 2001
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Ingår i: 19th Nordic Semiconductor Meeting. ; , s. 68-
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Konferensbidrag (refereegranskat)abstract
- The Heterostructure Barrier Varactor (HBV), first proposed by Kollberg et al. [1], has a symmetric C-V and an anti-symmetric I-V characteristic. Therefore it will only produce odd harmonics of the input frequency when used in mm- and submm-wave frequency multipliers, which greatly simplifies the multiplier design. The high-bandgap barriers prevent electron transport through the structure so that the depletion region of the modulation layers is controlled by the applied bias, thus modulating the capacitance of the device. By varying the number of barriers and the thickness and doping of the modulation layers, it is possible to tailor the HBV diode for various applications, e.g. power-handling capability and frequency of operation.We present four different InGaAs/InAlAs HBV materials on InP fabricated by MOVPE. Two are designed for high-power, mm-wave applications and the other two are optimised for high efficiency up to submm-wave frequencies. In order to handle high power levels, materials 1816 and 1817 have six barriers and a relatively low doping concentration which results in a high break-down voltage. The measured break-down voltage for 1817 of approximately 52 Volts for a current density of 0,1µA/µm2 is, to the best of our knowledge, the highest value reported for HBVs. Materials 1819 and 1820 have higher doping concentrations and shorter modulation layers to reduce losses and the effect of current saturation, see Table 1. Design methods and predicted RF-performance will be presented.
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| 17. |
- Ingvarson, Mattias, 1974, et al.
(författare)
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Heterostructure barrier Varactor Frequency Multipliers: Materials, Devices and Circuits
- 2001
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Ingår i: GigaHertz 2001.
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Konferensbidrag (refereegranskat)abstract
- The Heterostructure Barrier Varactor, HBV, diode is used in frequency multipliers at millimetre and sub millimetre wavelengths. Owing to its symmetrical properties only odd harmonics are generated, this greatly simplifies the design of frequency triplers and quintuplers. We report on new InP based material and device designs for planar, whisker contacted, and novel pillar structure HBVs. We present design methods with measured and simulated results. We also report on a new waveguide frequency tripler where HBV diodes are embedded in a microstrip environment together with the matching network for the fundamental and the third harmonic. Simulated results are presented for this new circuit topology, which is highly suitable for system integration
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| 18. |
- Ingvarson, Mattias, 1974, et al.
(författare)
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Thermal constraints for heterostructure barrier varactors
- 2004
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Ingår i: IEEE Electron Device Letters. - 0741-3106 .- 1558-0563. ; 25:11, s. 713-715
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Tidskriftsartikel (refereegranskat)abstract
- Current research on heterostructure barrier varactors (HBVs) devotes much effort to the generation of very high power levels in the millimeter wave region. One way of increasing the power handling capacity of HBVs is to stack several barriers epitaxially. However, the small device dimensions lead to very high temperatures in the active layers, deteriorating the performance. We have derived analytical expressions and combined those with finite element simulations, and used the results to predict the maximum effective number of barriers for HBVs. The thermal model is also used to compare the peak temperature and power handling capacity of GaAs and InP-based HBVs. It is argued that InP-based devices may be inappropriate for high-power applications due to the poor thermal conductivity of the InGaAs modulation layers.
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| 19. |
- Laisné, Alexander, et al.
(författare)
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A 500 GHz HBV Quintupler
- 2003
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Ingår i: THz2003. ; , s. P1-33
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Konferensbidrag (refereegranskat)
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| 20. |
- Olsen, Arne, 1974, et al.
(författare)
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A 100-GHz HBV frequency quintupler using microstrip elements
- 2004
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Ingår i: IEEE Microwave and Wireless Components Letters. - 1558-1764 .- 1531-1309. ; 14:10, s. 493-395
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Tidskriftsartikel (refereegranskat)abstract
- A new quintupler concept using a heterostructure barrier varactor (HBV) has been fabricated and measured. The multiplier consists of a quartz circuit mounted in a full height crossed waveguide block, and hence uses a mixture of waveguide components and microstrip elements. The embedding impedance for the fundamental frequency is provided by tuneable backshorts, whereas conventional microstrip circuit elements are used for impedance matching for the third and fifth harmonic. This topology is highly suitable for monolithic integration, and a peak conversion efficiency of 4.9 % was measured at 102.5 GHz with an input power of 13 dBm.
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| 21. |
- Olsen, Arne, 1974, et al.
(författare)
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A low cost fixed tuned F-band HBV frequency tripler
- 2003
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Ingår i: IEEE MTT+S International Microwave Symposium Digest. ; 2, s. 899-902
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Konferensbidrag (refereegranskat)abstract
- We present a novel fixed tuned heterostructure barrier varactor diode (HBV) tripler. This new multiplier consists of a microstrip section, which provides the critical impedance matching, and the diode, connected to microstrip to waveguide transitions at each end. The circuit is inserted in the E-plane of a waveguide mount, and both the input (Q-band) and the output (F-band) waveguide to microstrip transitions are realized using antipodal finlines. A peak efficiency of 4.2% with a 3% 3-dB bandwidth at 3x42.6 GHz for an input power of 13 dBm has been measured.
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| 22. |
- Olsen, Arne, 1974, et al.
(författare)
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A new waveguide integrated microstrip HBV frequency tripler
- 2001
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Ingår i: 9th International Conference on Terahertz Electronics.
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Konferensbidrag (refereegranskat)abstract
- We discuss a new Heterostructure Barrier Varactor (HBV) frequency tripler design, where HBV diodes are embedded in a microstrip environment together with the matching network for the fundamental and the third harmonic. The circuit is mounted in the E-plane of a reduced height Q-band waveguide with an F-band waveguide at the output. Antipodal finline tapers are used for the transitions between the waveguides and the microstrip circuit. Circuits for six-barrier InP HBV diodes have been designed and simulated with an output frequency at the F-band 90-140 GHz.
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| 23. |
- Olsen, Arne, 1974, et al.
(författare)
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Heterostructure barrier varactor frequency triplers and quintuplers for THz electronics
- 2003
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Ingår i: GigaHertz Symposium.
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Konferensbidrag (refereegranskat)abstract
- A fixed tuned tripler and a quintupler using the Heterostructure Barrier Varactor (HBV) diode are presented. The tripler utilise a novel arrangement of antipodal finline, for waveguide to microstrip transition, and microstrip elements for the diode matching. An output power of -0.8 dBm at 128 GHz was measured for the tripler, which is close to the simulated performance. For the quintupler, an output power of 5.6 dBm at 98 GHz is predicted when ideal circuit elements are used.
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| 24. |
- Olsen, Arne, 1974, et al.
(författare)
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Planar HBV triplers and quintuplers for millimetre wavelengths
- 2003
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Ingår i: 3rd ESA Workshop on Millimetre Wave Technology and Applications.
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Konferensbidrag (refereegranskat)abstract
- In this paper, various fixed tuned tripler and quintupler designs are presented. Measurement of a microstrip tripler, using antipodal finline for transition to waveguide, shows a good result with a output power of -0.8 dBm at 128 GHz compared to simulation. Furthermore, a quintupler realised with coplanar-waveguide have been simulated to provide a conversion efficiency of 6.7% at 100 GHz.
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| 25. |
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| 26. |
- Stake, Jan, 1971, et al.
(författare)
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Heterostructure-Barrier-Varactor Design
- 2000
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Ingår i: IEEE Transactions on Microwave Theory and Techniques. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9480 .- 1557-9670. ; 48:4, s. 677-682
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we propose a simple set of accurate frequency-domain design equations for calculation of optimum embedding impedances, optimum input power, bandwidth, and conversion efficiency of heterostructure-barrier-varactor (HBV) frequency triplers. A set of modeling equations for harmonic balance simulations of HBV multipliers are also given. A 141-GHz quasi-optical HBV tripler was designed using the method and experimental results show good agreement with the predicted results.
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| 27. |
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| 28. |
- Stake, Jan, 1971
(författare)
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Varactors
- 2002
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Ingår i: RF and Microwave Semiconductor Device Handbook.
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Offering a single volume reference for high frequency semiconductor devices, this handbook covers basic material characteristics, system level concerns and constraints, simulation and modeling of devices, and packaging. Individual chapters detail the properties and characteristics of each semiconductor device type, including: Varactors, Schottky diodes, transit-time devices, BJTs, HBTs, MOSFETs, MESFETs, and HEMTs. Written by leading researchers in the field, the RF and Microwave Semiconductor Device Handbook provides an excellent starting point for programs involving development, technology comparison, or acquisition of RF and wireless semiconductor devices.
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| 29. |
- Stake, Jan, 1971
(författare)
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Varactors
- 2000
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Ingår i: The RF and Microwave Handbook. - 084938592X ; 22, s. 7-1
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 30. |
- Strupinski, W., et al.
(författare)
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MOVPE strain layers - growth and application
- 2000
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Ingår i: Journal of Crystal Growth. ; 221, s. 20-25
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Tidskriftsartikel (refereegranskat)abstract
- The critical thickness, characteristic for the lattice-mismatch parameter, plays a key role in the growth of strain layers. The driving force for the 2D-3D transition can be minimized by slowing the relaxation of misfit strain. As a result the relatively smooth layer is deposited at lower temperature for the optimal growth rate. The quality of the InGaAs- and AlAs-strained layers deposited on InP substrate have been examined by the XRD, AFM and SIMS methods. Atomic force microscopy allows to observe 3D growth mode even for very thin layers. Relatively strong relaxation effects are recognized by surface roughness. Two-dimensional di!raction measurement is a much more sensitive tool for the estimation of relaxation degree. The observations results were applied in the heterostructure barrier varactor (HBV) diode. In order to minimize the conduction current through HBV two materials with different design of the barriers were studied: one heterostructure with three homogeneous lattice matched barriers consisting of 20nm Al0.48In0.52As and another one with strained step-like barriers consisting of 5 nm Al0.48In0.52As, 3 nm AlAs and 5 nm Al0.48In0.52As. We found that the use of strained step-like barriers results in a much lower conduction current. For current density
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