Engineering topics
Publications and source records attributed to Downing, R. G..
Electrical parametric data are presented on BSF, BSR, textured 10 ohm cm, 50 micron advanced OAST cells in graphical and tabular form as functions of solar illumination intensity, temperature, and 1 MeV electron fluence.
Electrical characteristics of Spectrolab HEWAC BSF, textured, 10 ohm cm, 225 micron solar cells are presented in graphical and tabular format as a function of solar illumination intensity and temperature.
A machine is described for attaching solar cells to a flexable substrate on which printed circuitry has been deposited. The strip is fed through: (1) a station in which solar cells are elevated into engagement with solder pads for the printed circuitry and thereafter heated by an infrared lamp; (2) a station at which flux and solder residue is removed; (3) a station at which electrical performance of the soldered cells is determined; (4) a station at which an encapsulating resin is deposited on the cells; (5) a station at which the encapsulated solar cells are examined for electrical performance; and (6) a final station at which the resulting array is wound on a takeup drum.
Electrical characteristics of Spectrolab BSF 200 micron Helios N/P silicon solar cells are presented in graphical and tabular format as a function of solar illumination intensity and temperature.
Electrical characteristics of hybrid multilayer antireflectance coated silicon solar cells are presented in graphical and tabular format as a function of solar illumination intensity and temperature.
Electrical characteristics of Solarex 50 micron-thick N/P silicon solar cells are presented in graphical and tabular format as a function of solar illumination intensity and temperature.
Electrical characteristics of OCLI violet N/P silicon solar cells are presented in graphical and tabular format as function of solar illumination intensity and temperature.
Reversible changes in solar cell performance were induced by AM1 illumination and evaluated by measuring short-circuit current, weak light spectral response, and minority carrier diffusion length. In n(+)p cells the change manifests itself as a reduced short-circuit current, a loss of the red response, and a reduction in minority carrier diffusion length. In p(+)n cells there are two-photon induced effects: (1) enhancement of the blue spectral response, presumably occurring in the p(+) layer and (2) degradation in open-circuit voltage at low light levels due to increased leakage occurring only after the junction edge is exposed to bright light. Most of these photon effects are attributed to defects in the silicon.
Several groups of lithium-doped solar cells have been evaluated under 1-MeV electron irradiation. Many of these groups indicated superior electrical output after irradiation and recovery as compared to similarly irradiated n/p solar cells. The superior cells are those with lithium concentrations of 2 to 5 x 10 to the 14th power atoms per cu cm at the junction. An irradiation of lithium-doped cells with 28-MeV electrons indicated a tenfold advantage of lithium-doped cells over n/p cells. Studies of the changes in the lithium concentration during recovery have shown the amounts of lithium reacting is highly nonlinear in regard to the electron fluence and varies greatly with distance from the junction. The results indicate that precipitation of lithium on radiation defects may be the cause of recovery rather than ion pairing.
Lithium doped solar cell hardness to 1 MeV electron irradiation
Hall, capacitance, and time-dependent measurements of radiation hardened Li-diffused solar cells
The current state of the art in radiation resistant lithium-doped silicon solar cells is reviewed. Fabrication techniques are reviewed. Characteristics of lithium-doped cells are discussed. Behavior of lithium-doped cells during 1 MeV electron irradiation are studied for various types of cells. Effects of variations in lithium and oxygen concentration are shown and discussed. Capacitance measurements at various voltages, frequencies and temperatures are used to detect charges in lithium donor concentration and the formation of defects during irradiation. Physical models to explain the observed effects are presented.
Recovery characteristics of electron irradiated, lithium doped, solar cells
Hall coefficient measurements of irradiated lithium doped solar cells
Hall coefficient measurements for lithium doped solar cells
Determination of optimum design for space utilized lithium doped solar cells
Lithium concentration and defects in doped radiation resistant silicon solar cells during electron irradiation
Optimum design for space utilized lithium doped solar cells