K. Moore, M. C De Baca, J-H. Huang, O. Hartin, H. Stewart,
S. Shaw, C. Gaw, T. Arnold, M. Miller, C.E. Weitzel, and J. Cotronakis
Freescale Semiconduct 2100 E. Elliot Rd. Tempe, AZ 85284 Karen.Moore@freescale.com 480-413-7571
Keywords: GaAs PHEMT, Field-Plate, RF Power, ACPR
GaAs PHEMT's have been the workhorse for microwave discretes and MMIC's for many years. Freescale Semiconductor has participated in this market for applications up to 3.55GHz using a backfilled gate process for devices with an operating voltage of 12V. We have also reported a number of enhancements to this device technology in the technical literature [1-2]. This paper reports on work to take this technology to the next level by achieving CW and ACPR performance at 5.8 GHz which is equivalent to the performance at 3.55 GHz . The use of a self-aligned field-plate was necessary to achieve RF gain > 10 dB while meeting all of the other performance targets with the same input match. This paper will review the epi structure, process, and device design that enabled this performance increase.