In this paper the effect of temperature transient on the large-signal properties and frequency chirping of 94 GHz pulsed silicon Double-Drift Region (DDR) Impact Avalanche Transit Time (IMPATT) device is investigated. A transient thermal model and a large-signal simulation method based on non-sinusoidal voltage excitation have been developed by the authors' to study the effect temperature transients on the large-signal characteristics and frequency chirping in pulsed Si DDR IMPATTs. Results show that the device is capable of delivering a peak pulsed power output of 17.5 W with 12.8% efficiency when the voltage modulation is 60%. The maximum junction temperature rise is 350.2 K for a peak pulsed bias current of 6.79 A with 100 ns pulsewidth and 0.5 percent duty cycle; whereas the chirp bandwidth is 8.3 GHz. © 2012 IEEE.

A ACHARYYA

J P BANERJEE

S BANERJEE

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Temperature transient effect on the large-signal properties and frequency chirping in pulsed silicon DDR IMPATTs at 94 GHz

CODEC 2012 - 5th International Conference on Computers and Devices for Communication

The authors have developed a quantum corrected drift-diffusion model for impact avalanche transit time (IMPATT) devices by coupling the density gradient model with the classical drift-diffusion model. A large-signal simulation technique has been developed by incorporating the quantum potentials in the current density equations for the analysis of double-drift region IMPATT devices based on different semiconductors such as Wurtzite–GaN, InP, type-IIb diamond (C), 4H–SiC and Si deigned to operate at different millimeter-wave (mm-wave) and terahertz (THz) frequencies. It is observed that, the RF power output and DC to RF conversion efficiency of the devices operating at higher mm-wave ($$>$$>140 GHz) and THz frequencies reduce due to the incorporation of quantum corrections in the model; but the effect of quantum corrections are negligible for the devices operating at lower mm-wave frequencies ($$\le $$≤140 GHz). © 2014, Springer Science+Business Media New York.

Journal of Computational Electronics

Quantum corrected drift-diffusion model for terahertz IMPATTs based on different semiconductors

Quantum correction is necessary on the classical drift-diffusion (CLDD) model to predict the accurate behavior of high frequency performance of ATT devices at frequencies greater than 200 GHz when the active layer of the device shrinks in the range of 150-350 nm. In the present work, a quantum drift-diffusion model for impact avalanche transit time (IMPATT) devices has been developed by incorporating appropriate quantum mechanical corrections based on density-gradient theory which macroscopically takes into account important quantum mechanical effects such as quantum confinement, quantum tunneling, etc. into the CLDD model. Quantum potentials (synonymous as Bohm potentials) have been incorporated in the current density equations as necessary quantum mechanical corrections for the analysis of millimeter-wave (mm-wave) and Terahertz (THz) IMPATT devices. It is observed that the large-signal (L-S) performance of the device is degraded due to the incorporation of quantum corrections into the model when the frequency of operation increases above 200 GHz; while the effect of quantum corrections are negligible for the devices operating at lower mm-wave frequencies. © 2014 Springer Science+Business Media New York.

Quantum drift-diffusion model for IMPATT devices

Large-signal (L-S) characterization of double-drift region (DDR) impact avalanche transit time (IMPATT) devices based on silicon designed to operate at different millimeter-wave (mm-wave) and terahertz (THz) frequencies up to 0.5 THz is carried out in this paper using an L-S simulation method developed by the authors based on non-sinusoidal voltage excitation (NSVE) model. L-S simulation results show that the device is capable of delivering peak RF power of 657.64 mW with 8.25% conversion efficiency at 94 GHz for 50% voltage modulation; whereas RF power output and efficiency reduce to 89.61 mW and 2.22% respectively at 0.5 THz for same voltage modulation. Effect of parasitic series resistance on the L-S properties of DDR Si IMPATTs is also investigated, which shows that the decrease in RF power output and conversion efficiency of the device due to series resistance is more pronounced at higher frequencies especially at the THz regime. The NSVE L-S simulation results are compared with well established double-iterative field maximum (DEFM) small-signal (S-S) simulation results and finally both are compared with the experimental results. The comparative study shows that the proposed NSVE L-S simulation results are in closer agreement with experimental results as compared to those of DEFM S-S simulation. Copyright © Cambridge University Press and the European Microwave Association 2013.

International Journal of Microwave and Wireless Technologies

Large-signal characterization of DDR silicon IMPATTs operating up to 0.5 THz

An attempt is made in this paper to study the influence of skin depth on the parasitic series resistance of millimeter-wave IMPATT devices based on Silicon. The method is based on the concept of depletion width modulation of the device under large-signal condition. A large-signal simulation model based on non-sinusoidal voltage excitation is used for this study. The electric field snap-shots of 35 GHz Single-Drift Region (SDR) and 94 GHz Double-Drift Region (DDR) IMPATT devices are first obtained from which the series resistances are estimated by incorporating the effect of skin depth in the modeling and simulation. The series resistances of these devices are also obtained by neglecting the effect of skin depth. The values of series resistances obtained from the simulation are compared with the corresponding experimentally reported values. It is observed that the series resistance estimated by including the skin effect is in closer agreement with the experimental values as compared to that without including the same. Thus the skin effect plays an important role for determining the series resistance of IMPATT devices at millimeter-wave frequency bands. © 2013 Springer Science+Business Media New York.

Influence of skin effect on the series resistance of millimeter-wave IMPATT devices

The authors have carried out the large-signal characterization of silicon-based double-drift region (DDR) impact avalanche transit time (IMPATT) devices designed to operate up to 0.5 THz using a large-signal simulation method developed by the authors based on non-sinusoidal voltage excitation. The effect of band-to-band tunneling as well as parasitic series resistance on the large-signal properties of DDR Si IMPATTs have also been studied at different mm-wave and THz frequencies. Large-signal simulation results show that DDR Si IMPATT is capable of delivering peak RF power of 633.69 mW with 7.95% conversion efficiency at 94 GHz for 50% voltage modulation, whereas peak RF power output and efficiency fall to 81.08 mW and 2.01% respectively at 0.5 THz for same voltage modulation. The simulation results are compared with the experimental results and are found to be in close agreement. © 2013 Chinese Institute of Electronics.

Journal	CODEC 2012 - 5th International Conference on Computers and Devices for Communication
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