Frayssinet E.,French National Center for Scientific Research |
Cordier Y.,French National Center for Scientific Research |
Schenk H.P.D.,Picogiga International |
Physica Status Solidi (C) Current Topics in Solid State Physics | Year: 2011
In this paper, we report on the growth of thick gallium nitride (GaN) layers on 4-in. and 6-in., (111)-orientated silicon substrates by metalorganic vapor phase epitaxy. Up to 4 μm thick continuous GaN layers have been obtained by inserting both SiN and AlN interlayers into the structure. With dislocation densities of about 1-2×109 cm-2 and GaN(002) and (302) X-ray rocking curve full widths at half maximum of 420 and 1360 arcsec for 4-in. and 374 and 810 arcsec for 6-in., respectively, the final continuous GaN layer exhibits excellent crystalline properties. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Simon W.,IMST GmbH |
Baggen L.,IMST GmbH |
2010 14th International Symposium on Antenna Technology and Applied Electromagnetics and the American Electromagnetics Conference, ANTEM/AMEREM 2010 | Year: 2010
RF-MEMS is an emerging area of MEMS technology that is revolutionizing RF- and microwave applications. RF-MEMS devices have a broad range of applications in military and commercial wireless communication, navigation and sensor systems. Agile RF-systems require reconfigurable froutends that can steer the beam over a wide frequency range. Such applications always require some kind of switches. The RF MEMS switch technology presented in this paper has been combined with a standard commercial GaAs MMIC process from the OMMIC foundry. Several switches have been designed and evaluated within the FP7 project MEMS-4-MMIC. Such switches can be used in compact designs of switching matrices, routing networks and/or phase shifters. One application range is electronically steerable antenna arrays that can be used for radar applications, satellite communication and sensory [1-6]. A 3D FDTD field solver has been used for the electromagnetic design of all switches presented within this article. © 2010 IEEE.
Ciccognani W.,University of Rome Tor Vergata |
Limiti E.,University of Rome Tor Vergata |
Longhi P.E.,EltElettronica SpA |
IEEE Journal of Solid-State Circuits | Year: 2010
Radioastronomy applications, as well as others, require ultra-low-noise front ends for high-sensitivity receivers. In this way, the image produced from a radio-telescope using such advanced components has a higher resolution and therefore allows scientists to obtain a clearer representation of the environment. The low-noise amplifier is the key component of a high sensitivity receiver (demonstrating a very low noise figure, even in the millimeter-wave frequency region). Such electrical performance is obtained from the combined use of an advanced technology (fT and fmax > 250 GHz, LG, < 0, 1 μm) and appropriate design methodologies that take into account electrical specifications and system constraints in the context of the targeted application. In this contribution, we will present both the performance of the employed technology (OMMIC 70 nm GaAs mHEMT) and the related low-noise design methodologies that have led to the realization of four different LNAs operating from 5 GHz up to 100 GHz and beyond. © 2006 IEEE.
Soitec, Ommic and French National Center for Scientific Research | Date: 2012-06-28
The invention relates to a method for manufacturing, by means of epitaxy, a monocrystalline layer of GaN on a substrate, wherein the coefficient of thermal expansion is less than the coefficient of thermal expansion of GaN, comprising the following steps: (b) three-dimensional epitaxial growth of a layer of GaN relaxed at the epitaxial temperature, (c1) growth of an intermediate layer of B
Rantakari P.,VTT Technical Research Center of Finland |
Malmqvist R.,Subsystem Technologies |
Samuelsson C.,Subsystem Technologies |
Leblanc R.,OMMIC |
And 6 more authors.
IET Microwaves, Antennas and Propagation | Year: 2011
In this study, the authors present the designs and experimental results of radio frequency (RF) micro electro-mechanical systems (MEMS) switches and switching circuits for gallium arsenide (GaAs)-based monolithic microwave-integrated circuits (MMIC). The switches and switching networks [single-pole single throw (SPST), single-pole double throw and double-pole double throw] are fabricated using OMMIC's GaAs MMIC foundry process technology. Measured results for a wide-band SPST switch design show isolation better than 20 dB up to 80 GHz with impedance matching better than -15 dB and insertion loss below 1.6 dB. Such low-loss GaAs-based RF MEMS switches are also capable of sustaining a power level of more than 10 W (up to 41 dBm) at 1 and 4 GHz, respectively, during cold-switching cycling conditions. Finally, to highlight the possibilities and benefits of monolithic integration of such MEMS switches and active RF devices on the same GaAs substrate, we present the experimental results of a wide-band (i.e. more than 10-40 GHz) GaAs MEMS-enabled switched low-noise amplifier circuit. © 2011 © The Institution of Engineering and Technology.