Title :
Final Flight Data Report from ASCOT
Author_Institution :
Aerosp. Corp., Los Angeles, CA
Abstract :
This paper presents selected results from five years of flight data obtained by the Advanced Solar Cell Orbital Test (ASCOT). The experiment contains five types of advanced cells, including GaAs/Ge single junction devices from both Tecstar and Spectrolab, and two types of silicon cells as reference devices. The total equivalent 1 MeV electron fluence received by the silicon cells exceeds 1.2E16/cm2 , giving this experiment the highest cumulative radiation exposure of any to date. Complete IV curves were obtained for the entire period, and these have been compared with models of predicted degradation. The degradation of the silicon reference devices suggests a highly dynamic trapped proton environment, not well represented by the standard AP8 model, that is confirmed by dosimeters flown concurrently on spacecraft in similar orbits. Evidence of annealing in the GaAs devices is apparent during naturally occurring periods of low proton flux
Keywords :
III-V semiconductors; annealing; dosimeters; elemental semiconductors; environmental degradation; gallium arsenide; germanium; radiation effects; semiconductor heterojunctions; silicon; solar cells; space power generation; space vehicles; ASCOT; Advanced Solar Cell Orbital Test; GaAs-Ge; I-V curves; Spectrolab; Tecstar; annealing; device degradation; dosimeters; dynamic trapped proton environment; electron fluence; flight data; proton flux; silicon cells; single junction devices; space radiation exposure; spacecraft; Degradation; Electrons; Gallium arsenide; Orbits; Photovoltaic cells; Predictive models; Protons; Silicon; Space vehicles; Testing;
Conference_Titel :
Photovoltaic Energy Conversion, Conference Record of the 2006 IEEE 4th World Conference on
Conference_Location :
Waikoloa, HI
Print_ISBN :
1-4244-0017-1
Electronic_ISBN :
1-4244-0017-1
DOI :
10.1109/WCPEC.2006.279873
