Latest Results of HgCdTe 2048 x 2048 and Silicon Focal Plane Arrays C.A.Cabelli a , a D.E.Cooper, a A.Haas, a L.J.Kozlowski, a G.Bostrup, a A.C. Chen, a J.D. Blackwell, a J.T. Montroy, a K Vural, b W.E. Kleinhans, c K.W. Hodapp, D. Hall a Rockwell Science Center, Thousand Oaks, CA 91360 b Valley Oak Semiconductor, Westlake Village, CA 91362 c University of Hawaii, Institute for Astronomy, Honolulu, Hawaii 96822 ABSTRACT The world's first 2048 x 2048 infrared focal plane array (FPA) has been developed by Rockwell Science Center for infrared astronomy. The Hawaii-2 is the largest CMOS multiplexer designed to date, created to service a variety of both infrared and Silicon detector arrays. The 18m pixel pitch was selected to accommodate both reasonable telescope optics and maximize yield in the fabrication of such a large readout. The fabrication uses world-class sub-micron photolithography to maximize yield of high quality devices. We will report on the characterization of FPA's using the Hawaii-2 multiplexer mated to SWIR detector arrays with a spectral response of 0.9m to 2.5m. These detector arrays have been processed by Liquid Phase Epitaxy (LPE) HgCdTe on sapphire substrates, also known as PACE-1. We also report on characterization of Silicon detectors in terms of their quantum efficiency, spectral response, and dark current. Keywords: Hawaii-2, Hawaii, infrared, PACE-1, FPA, CMOS, and MCT 1.0 INTRODUCTION Rockwell Science Center has always been an innovator in designing and developing large format staring arrays such as the NICMOS3, PICNIC, and HAWAII just to name a few. Building upon this leadership Rockwell has created the Hawaii-2, a 2048 x 2048 pixels array for use in astronomical applications. The flexibility of this multiplexer allows for a multitude of different detector materials to by mated to it, enabling for a wide variety of applications. These large arrays allow astronomers to make more efficient use of valuable observing time on today's expensive telescopes. A MWIR/visible (0.4 m - 5m) version of this FPA is under development and will be proposed for the Next Generation Space Telescope (NGST) program. In this review we will summarize the development of the Hawaii-2 multiplexer, the different detector materials under development, and the latest results from a PACE-1 HgCdTe SWIR 2048 x 2048 pixel hybrid. 2.0 CMOS READOUT Rockwell has been able to exploit the improvements in commercial CMOS fabrication by creating very large CMOS multiplexers with up to thirteen million transistors. The decrease in minimum design rules has allowed for more sophisticated designs to be yielded. Figure 1 shows the trend in increasing readout circuit complexity.