Computer studies of quasi Read gallium arsenide IMPATT diode : including the effect of space charge
01 Apr 1997-International Journal of Electronics (Taylor & Francis Group)-Vol. 82, Iss: 4, pp 335-346
TL;DR: In this article, computer studies have been carried out on the effects of variation of impurity hump parameters of quasi-read high-low (hi-lo) and low-high-low gallum arsenide IMPATT diodes on their DC and microwave properties.
Abstract: Computer studies have been carried out on the effects of variation of impurity hump parameters of quasi Read high–low (hi–lo) and low–high–low (lo-hi–lo) gallum arsenide IMPATT diodes on their DC and microwave properties. The effect of mobile space charge has been included in the computer analysis. It turns out that the DC properties of the diode are sensitive functions of the width and doping concentration of impurity bumps. The optimum efficiency is found to be respectively 24.5% and 27.9% for hi–lo and lo-hi–lo diodes designed for 18 GHz frequency. The small signal admittance calculations show that a lo-hi–lo structure provides higher negative conductance and better quality factor compared with a hi–lo structure of GaAs Impatt diode.
Citations
More filters
TL;DR: In this article, the space charge effect on the performance of a double drift region (DDR) impact ionization and avalanche transit time (GIMPATT) diode was investigated.
Abstract: Avalanche multiplication process in avalanche transit time devices results in large number of electrons-hole pairs (EHPs). Therefore, there is considerable temperature rise in the junction. This high temperature than normal operating one, leads to large space charge effects by creating extra space charges. As a result, practical efficiency of transit time devices is below 30%. It is quite important to understand the effects of space charges on device performances. The space charge effect is computationally studied and analysed here for the graphene material based double drift region (DDR) impact ionization and avalanche transit time (GIMPATT) diode. Also, the effect in GIMPATT is compared with IMPATT based on other material like Si, Ge, GaAs, WzGaN, InP, 4H–SiC.
1 citations
01 Jan 2016
TL;DR: In this article, the DR in nano-wires of HD III-V semiconductors in the presence of cross fields has been investigated in Sect. 1.2.1.
Abstract: In this chapter the DR in Quantum Wells of HD III–V semiconductors in the presence of magnetic field have been formulated in Sect. 1.2.1. On the basis of these fundamental equations, the DR in Nano Wires of HD III–V semiconductors in the presence of magnetic field has been investigated in Sect. 1.2.2. The Sect. 1.2.3 explores the DR in Quantum Dot of HD III–V semiconductors in the presence of magnetic field. The DR in Quantum Wells of HD III–V semiconductors in the presence of cross fields has been investigated in Sect. 1.2.4. The DR in Nano-Wires of HD III–V semiconductors in the presence of cross fields has been studied in Sect. 1.2.5. The DR in Quantum Dot of HD III–V semiconductors in the presence of cross fields has been investigated in Sect. 1.2.6. The DR in Quantum Wells of HD IV–VI semiconductors in the presence of magnetic field has been studied in Sect. 1.2.7. The DR in Nano Wires of HD IV–VI semiconductors in the presence of magnetic field has been investigated in Sect. 1.2.8. The DR in Quantum Dot of HD IV–VI semiconductors in the presence of magnetic field has been studied in Sect. 1.2.9. The DR in cylindrical Quantum Dot of III–V semiconductors in the presence of crossed electric and magnetic fields has been investigated in Sect. 1.2.10. The DR in Quantum Wells of HD III–V Semiconductors in the presence of arbitrarily oriented magnetic field has been studied in Sect. 1.2.11. The Sect. 1.4 contains 16 open research problems, which form the integral part of this chapter.
1 citations
01 Jan 2021
TL;DR: In this paper, the influence of terahertz frequency on the elastic constants in extremely degenerate (ED) 2D systems taking quantized films (QFs) and accumulation layers (ALs) of nonlinear optical, tetragonal, ternary, quaternary, III-V, II-VI, IV-VI and strained compounds, respectively, was investigated.
Abstract: We investigate the influence of terahertz frequency on the elastic constants in extremely degenerate (ED) 2D systems taking quantized films (QFs) and accumulation layers (ALs) of nonlinear optical, tetragonal, ternary, quaternary, III–V, II–VI, IV–VI and strained compounds, respectively. It has been found taking ED QFs and ALs of specific materials of the important 2D electronic compounds as examples that the elastic constants (C1 and C2) change with nano-size of the said QFs and the two-dimensional carrier statistics per unit area in different oscillatory ways. The influence of electric field for both the limits in inversion layers of non-parabolic materials has also been studied. Besides, C1 and C2 are in nice agreement with our suggestive relationships for determining them experimentally.
TL;DR: In this paper, the effect of position shifting of charge bump on different microwave parameters, such as the negative resistance, noise measure, quality factor, and series resistance of one-dimensi...
Abstract: In this paper, the effect of position shifting of charge bump on different microwave parameters, such as the negative resistance, noise measure, quality factor, and series resistance of one-dimensi...
01 Jan 2021
TL;DR: In this article, the carrier statistics in quantized extremely degenerate III-V, ternary, quaternary and tetragonal compounds were studied and the influence of photo-excitation and electric field on the Fermi energy was investigated.
Abstract: In this chapter, we study the carrier statistics (CS) in quantized extremely degenerate III–V, ternary, quaternary and tetragonal compounds respectively. We have also investigated the influence of photo-excitation and electric field on the Fermi energy. We note by taking various types of opto-electronic materials as examples that the Fermi energy oscillates with inverse magnetic field due to SdH effect, changes with changing electric field, light intensity, wave length and alloy composition in different ways which are totally energy band constants dependent.
References
More filters
TL;DR: In this paper, a general small-signal theory of the avalanche noise in IMPATT diodes is presented, which is applicable to structures of arbitrary doping profile and uses realistic (α
eq \beta in Si) ionization coefficients.
Abstract: A general small-signal theory of the avalanche noise in IMPATT diodes is presented. The theory is applicable to structures of arbitrary doping profile and uses realistic ( \alpha
eq \beta in Si) ionization coefficients. The theory accounts in a self-consistent manner for space-charge feedback effects in the avalanche and drift regions. Two single-diffused n-p diodes of identical doping profile, one of germanium and the other of silicon, are analyzed in detail. For description of the noise of the diodes as small-signal amplifiers the noise measure M is used. Values for M of 20 dB are obtained in germanium from effects in the depletion region only, i.e., when parasitic end region resistance is neglected. Inclusion of an assumed parasitic end resistance of one ohm for a diode of area 10-4cm2produces the following noise measure at an input power of 5×104W/cm2, and at optimum frequency: germanium 25 dB, silicon 31 dB. For comparison, a noise figure of 30 dB has been reported [1] for a germanium structure of the same doping profile as used in the calculations. Measurements of silicon diodes of the same doping profile are not available, but typically silicon diodes give 6-8 dB higher noise figures than germanium diodes of comparable doping profile.
233 citations
01 Aug 1971
TL;DR: A brief review summarizes mechanisms of operation, power output, efficiency, noise, and some important features of design and fabrication of microwave avalanche diodes of various types.
Abstract: Microwave avalanche diodes of various types (IMPATT, TRAPATT, etc.) can generate power sufficient for microwave receivers and some transmitters. This brief review summarizes mechanisms of operation, power output, efficiency, noise, and some important features of design and fabrication.
112 citations
TL;DR: In this paper, the ionization rates for electrons and holes are expressed as α=5.6×106 exp(−2.41×106/E) and β=1.5×106
Abstract: Ionization rates in GaAs are determined from the measurement of photocarrier multiplication. Pure electron and hole initiations are achieved by using the novel crater mesa structure and appropriate optical‐injection wavelengths. The ionization rates for holes are greater than that for electrons except at highest fields. This agrees with the studies of Stillman et al., except for the individual values. The ionization rates for electrons and holes are expressed as α=5.6×106 exp(−2.41×106/E) and β=1.5×106 exp(−1.57×106/E), respectively.
64 citations
TL;DR: In this article, the authors used liquid phase epitaxy to grow n−n+n epitaxial triple layers to fabricate light-hi-lo GaAs IMPATT devices with an average output power of 2.8 W at 10 GHz.
Abstract: n‐n+‐n epitaxial triple layers were grown by liquid phase epitaxy to fabricate lo‐hi‐lo GaAs IMPATT devices. The best diode gave 35.6% cw efficiency with 2.9‐W output power at 10.4 GHz. From a group of 151 devices, 51% had better than 22% efficiency with an average output power of 2.8 W at 10 GHz. Operating voltages varied between 40 and 55 V. A theoretical efficiency of 46% was calculated for narrow spike structures using a quasistatic computer simulation.
42 citations
TL;DR: A dc-to-rf conversion efficiency of 37% combined with an output power of 3.4 W at 3.3 GHz has been obtained from a Schottky-barrier GaAs IMPATT diode having a lo-hi-lo profile.
Abstract: A dc‐to‐rf conversion efficiency of 37% combined with an output power of 3.4 W at 3.3 GHz has been obtained from a Schottky‐barrier GaAs IMPATT diode having a lo‐hi‐lo profile. The donor spike or clump was produced by implanting silicon into an epitaxial layer with a n‐type concentration of 1.65×1015 cm−3. Pyrolytic Si3N4 was used to encapsulate the GaAs during the postimplantation anneal. For these devices, the Si3N4 deposition procedure was found to be critical and had to be optimizied to achieve reproducible results. The devices have had very uniform electrical characteristics, and a large yield of devices with greater than 30% efficiency has been obtained. These results indicate that implantation can be used to produce lo‐hi‐lo IMPATT’s with significantly higher device yields than have been obtained by epitaxial techniques.
41 citations