Graded-barrier graded-channel InP pseudomorphic power HEMT with 40% power added efficiency and 200 mW output power at 60 GHz
Summary form only given. We present state-of-the-art power and PAE results of InGaAs-InAlAs-InP HEMTs with optimized graded channel and graded Schottky barrier layers which demonstrate, for the first time, that InP-based HEMTs have a considerably better power/PAE combination than GaAs-based HEMTs at V-band. The 0.15 /spl mu/m gate length, eight gate finger, 500 /spl mu/m wide InP HEMTs were measured in a fixture under continuous wave (CW) conditions and showed 23 dBm (200 mW) output power and 40% PAE at 60 GHz with an input power of 17 dBm, a drain bias of 3 V, and a drain current of 125 mA. These results represent the best reported V-band power/PAE performance to date, and a comparison of these results with previously reported results for both InP- and GaAs-based HEMTs is shown. Our state-of-the-art results are attributed to the use of an optimized heterostructure incorporating pseudomorphic graded channel and graded Schottky barrier layers, and the use of compact 15 /spl mu/m/spl times/25 /spl mu/m dry etched through-substrate vias (substrate thickness of 50 /spl mu/m). The heterostructure was designed to achieve high gain, current (Imax) and breakdown voltage; all of which are requirements for a device with high power and PAE.
A high performance and low DC power V-band MMIC LNA using 0.1 mu m InGaAs/InAlAs/InP HEMT technology
We report the design and performance of state-of-the-art V-band MMIC LNA's using 0.1- mu m gate length pseudomorphic In/sub 0.60/Ga/sub 0.40/As/In/sub 0.52/Al/sub 0.48/As/InP HEMT's. The three-stage V-band LNA demonstrated an average of 3.0 dB noise figure between 56-64 GHz with 24-25.5 dB associated gain with a noise figure of 2.7 dB measured at 62 GHz. Furthermore, the DC power dissipation of this circuit was only 19.5 mW which is less than one-third the DC power dissipation of InGaAs/AlGaAs/GaAs HEMT versions. These results demonstrate the excellent potential of InP HEMT technology for millimeter-wave and low DC power applications.<<ETX>>
Contractor Failure: Analysis
The possibility exists for any construction contractor to fail to filfill the contract requirements associated with a facility. Contractor failure occurs when a contractor is unable to perform his/her contractual duties, thus requiring the facility owner to invoke the contract's nonperformance clause. This paper provides aggregate contractor business failure statistics and outlines potential causes for failure. A framework to identify and quantify the associated costs is also introduced. Several case studies are presented to examine the cause and cost of failure and the means by which the facilities were completed. Alternatives available for project completion when contractor failure occurs are discussed. Recommendations to identify and monitor contractors at high risk for failure are outlined as well. This paper provides facility owners with a greater awareness of the possibility of contractor failure, how to quantify costs of contractor failure, and avoidance techniques.