Growth mechanism of &amp;lt;100&amp;gt; dark-line defects in high radiance GaAlAs LED's

Abstract

The dependence of the growth velocity of dark-line defects on current density, temperature and acceptor doping was investigated in the GaAlAs LED's. The velocity depends strongly on the current density (J) and acceptor doping(carrier concentration;P). But it does not depend on the ambient temperatures(20∼250°C). The current density dependence of the velocity (V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DLD</inf> ) was shown as V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DLD</inf> ∝ J 2 . Acceptor doping dependence was separated in to two regions; V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DLD</inf> ∝ p -1/3 (where 10 16 ≤ p ≤ 5×10 18 cm -3 ) and V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DLD</inf> ∝ p -3 (where p ≥ 5×10 18 cm -3 ). The growth of DLD during the operation is presumably limited by the interactions with impurities. Slow degradation of the LED's without dark structures was also investigated, and the extrapolated half-life in excess of 4×10 7 h was estimated.