METASTABILITY EFFECT IN SOLAR BLIND UV AMORPHOUS-SILICON CARBIDE PHOTODETECTOR

We present a study of the behavior under illumination of an ultraviole t detector based on a hydrogenated amorphous silicon and silicon carbi de p-i-n heterostructure. An efficiency (around 80%) is obtained at 50 nm together with a visible rejection. We found that under ultraviolet illumination the photocurrent increases to three times the initial va lue, whereas it remains almost constant under visible light. This beha vior is ascribed to the light activation of baron dopant in the p-laye r and is investigated by a simple equivalent circuit of the structure. This model can be utilized to optimize the geometry of the metal grid and thus the performance of the device. (C) 1998 Elsevier Science B.V . All rights reserved.