Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Radiation effects on p+n InP junctions grown by MOCVD

Conference ·
OSTI ID:36428
; ; ;  [1]
  1. Naval Research Lab., Washington, DC (United States)
The superior radiation resistance of InP over other solar cell materials such as Si or GaAs has prompted the development of InP cells for space applications. The early research on radiation effects in InP was performed by Yamaguchi and co-workers who showed that, in diffused p-InP junctions, radiation-induced defects were readily annealed both thermally and by injection, which was accompanied by significant cell recovery. More recent research efforts have been made using p-InP grown by metalorganic chemical vapor deposition (MOCVD). While similar deep level transient spectroscopy (DLTS) results were found for radiation induced defects in these cells and in diffused junctions, significant differences existed in the annealing characteristics. After injection annealing at room temperature, Yamaguchi noticed an almost complete recovery of the photovoltaic parameters, while the MOCVD samples showed only minimal annealing. In searching for an explanation of the different annealing behavior of diffused junctions and those grown by MOCVD, several possibilities have been considered. One possibility is the difference in the emitter structure. The diffused junctions have S-doped graded emitters with widths of approximately 0.3 micrometers, while the MOCVD emitters are often doped with Si and have widths of approximately 300A (0.03 micrometers). The difference in the emitter thickness can have important effects, e.g. a larger fraction of the total photocurrent is generated in the n-type material for thicker emitters. Therefore the properties of the n-InP material may explain the difference in the observed overall annealing behavior of the cells.
Research Organization:
National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center
OSTI ID:
36428
Report Number(s):
N--95-20502; NASA-CP--3278; E--9083; NAS--1.55:3278; CONF-9406314--
Country of Publication:
United States
Language:
English

Similar Records

Annealing of irradiated n+p InP buried homojunctions
Conference · Thu Sep 01 00:00:00 EDT 1994 · OSTI ID:36432

Space radiation effects in InP solar cells
Conference · Sat Nov 30 23:00:00 EST 1991 · IEEE Transactions on Nuclear Science (Institute of Electrical and Electronics Engineers); (United States) · OSTI ID:5832447

The growth and radiation response of n{sup +}p deep homojunction InP solar cells
Conference · Fri Dec 30 23:00:00 EST 1994 · OSTI ID:191215