Reverse Current Blocking Diodes for Flexible Solar Array Protection.

摘要

A unique Solar Cell Blocking Diode for use on solar panels is described. The device has the physical characteristics of a solar cell and the electrical properties of conventional diodes currently used for solar array reverse current isolation and protection. This combination of physical characteristics and electrical properties permits mounting of the diode on the panel surface in series with solar cells, and is particularly useful for flexible rollup solar arrays. The diode junction is diffused into a 1 x 2 cm, 8 mil thick, P-doped silicon blank. Nominal inverse voltage standoff characteristics of 140 volts at 1 mA leakage have been achieved with 20 ohm-cm base resistivity, 6 micrometer diffused junctions, and heavy silicon monoxide layers for surface passivation. Typical forward voltage drop at 0.3/3.0 amperes are of the order of 0.8/1.2 volts. Conventional diodes exhibit nominal inverse voltage standoff characteristics of 100 volts at 25 microamperes leakage, and typical forward voltage drop of 0.8/1.0 volt at 0.3/3.0 amperes. (Author)