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In this paper, we have presented the experimental results of phosphorus diffusion in silicon for the cases of rapid thermal processing (RTP) and rapid photothermal processing (RPP). In the case of the RPP, other than thermal energy, the vacuum ultraviolet photons are used as an additional source of energy. We have investigated the secondary-ion-mass-spectroscopy impurity profiles at different concentrations of P in Si. Based on our own experimental results and the data published in the open literature, we have provided an explanation of the enhanced diffusion both for the RTP and RPP cases. The thermal factor leads to the excitation (vibration) of atoms and quantum energy to the electron system excitation. As compared with the pure thermal process, the quantum-energy contribution provides a reduced activation energy and a higher diffusion coefficient.

High-quality DuPont screen-printed Ag contacts were achieved on high sheet-resistance emitters (100 /spl Omega//sq) by rapid alloying of PV168 Ag paste. Excellent specific contact resistance (/spl sim/1 m/spl Omega/-cm/sup 2/) in conjunction with high fill factor (FF) (0.775) were obtained on 100 /spl Omega//sq emitters by a 900/spl deg/C spike firing of the PV168 paste in a belt furnace. The combination of the alloying characteristics of the PV168 Ag paste and optimized single-step rapid low-thermal budget firing resulted in a cost-effective manufacturable process for high-efficiency Si solar cells. In addition, the co-fired 100 /spl Omega//sq cell showed a noticeable improvement of /spl sim/0.5% in absolute efficiency over a conventional co-fired 45 /spl Omega//sq emitter cell. Lighter doping in the 100 /spl Omega//sq emitter cell resulted in better blue-response compared to the conventional cell, contributing to /spl sim/1.3 mA/cm/sup 2/ improvement in short-circuit current. Improved surface passivation on 100 /spl Omega//sq emitter cell resulted in additional 0.6 mA/cm/sup 2/ increase in J/sub sc/, 15-mV higher V/sub oc/, and a 0.6% increase in absolute cell efficiency. Front grid design optimization resulted in a FF of 0.780, and a further improvement in cell efficiency to reach 17.4%.

This research details the development of technologies and methodologies that enable distributed spacecraft systems by supporting integrated navigation, communication, and control. Operating at the confluence of these critical functions produces capabilities needed to realize the promise of distributed spacecraft systems, including improved performance and robustness relative to monolithic space systems. Navigation supports science data association and data alignment for distributed aperture sensing, multipoint observation, and co-observation of target regions. Communication enables autonomous distributed science data processing and information exchange among space assets. Both navigation and communication provide essential input to control methods for coordinating distributed autonomous assets at the interspacecraft system level and the intraspacecraft affector subsystem level. A technology solution to implement these capabilities, the Crosslink Transceiver, is also described. The Crosslink Transceiver provides navigation and communication capability that can be integrated into a developing autonomous command and control methodology for distributed spacecraft systems. A small satellite implementation of the Crosslink Transceiver design is detailed and its ability to support broad distributed spacecraft mission classes is described.

One of the steps in creating a mathematical model of a system is to test the model after it has been fully specified, to see whether it is performing adequately. Often, it is found that the model is not performing acceptably (e.g. the model is not giving accurate predictions of the performance of the actual system). The same lack of fidelity can also be observed in established models that had been performing well, indicating a change in the actual system. At this point, it is necessary to diagnose where the problem in the model lies; a process called error isolation. An error isolation technique for detecting the misspecified parameter (or set of parameters) is described. This technique is especially designed for use on state-space models of large-scale systems. The authors report on an example of an application of the methodology to localizing errors in the model of an inertial navigation system. >