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The suitability of AlGaN/GaN HEMTs on SiC is discussed with respect to mm-wave applications at 40 GHz and beyond. A 0.15 μm T-gate AlGaN/GaN-HEMT 2-inch technology on SiC and sapphire was developed for high power applications and for frequencies beyond 30 GHz. Large periphery devices with 0.48 mm gate width show a cw output power of 0.86 W at 40 GHz. AlGaN/GaN dual-gate HEMTs show MSG/MAG of >13 dB at 60 GHz with 0.15 μm gate length. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

This paper describes the software tool which has been developed for the design of the superconducting magnets for the Large Hadron Collider (LHC) at CERN. Applied methods include numerical field calculation with a reduced vector-potential formulation, the application of vector-optimization methods, and the use of genetic as well as deterministic minimization algorithms. Together with the applied concept of features, the software tool is used as an approach towards integrated design of superconducting magnets. The main quadrupole magnet for the LHC, which was designed at CEA Saclay (France) using a different approach, was chosen as an example for the integrated design process. The paper focuses on the design issues and is not a project report on the main quadrupoles under construction.