D. Seghier et Hp. Gislason, Investigation of persistent photoconductivity in nitrogen-doped ZnSe/GaAs heterojunctions grown by MBE, J CRYST GR, 214, 2000, pp. 511-515
We report persistent photocurrent in p-type nitrogen-doped ZnSe epilayers g
rown by molecular-beam epitaxy on GaAs. It is observed up to room temperatu
re in some samples with a decay time ranging from several minutes to hours.
A typical decay consists of an initial stretched-exponential transient and
a subsequent slower transient. We demonstrate that the persistent photocur
rent has two components, one of them originating from the presence of metas
table centers in the ZnSe layer at the heterointerface, the other from tunn
eling of trapped holes from a two-dimensional quantum well at the heterojun
ction through its energy barrier. (C) 2000 Elsevier Science B.V. All rights
reserved.